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Some of the Chemical and Physical Characteristics of the Graff River in Kut City, Iraq
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作者 Salih Mahdi Ali Imad Kazem Ali 《Open Journal of Modern Hydrology》 CAS 2024年第1期56-67,共12页
Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period fro... Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period from October/2018 to March/2019, Seven variables of river water have been analyzed: temperature PH, electrical conductivity, TDS, turbidity, alkaline, and chloride. The results showed that most of the chemical and physical water properties of the river were in normal proportions and did not rise, except for the turbidity, which was at a very high level, and that the pH values were close to the basal side. The results of the statistical analysis revealed positive significant relationships between the pH and (chloride and TDS). On the other hand, between electrical conductivity and both previous variables as well. And a negative significant connection between temperature and alkaline. 展开更多
关键词 Graff River Kut City Iraq Chemical characteristics physical characteristics
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Dynamic physical characteristics of DC arc on arcing horn for HVDC grounding electrode line
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作者 刘益岑 杨晨光 +4 位作者 郭裕钧 张血琴 肖嵩 高国强 吴广宁 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期80-87,共8页
The dynamic physical characteristics of a DC arc on an arcing horn for a high voltage direct current(HVDC)grounding electrode line are significantly different from those of the switching device arc,secondary arc,AC fa... The dynamic physical characteristics of a DC arc on an arcing horn for a high voltage direct current(HVDC)grounding electrode line are significantly different from those of the switching device arc,secondary arc,AC fault arc and pantograph-catenary arc.In this work,an experimental platform for the DC arc on the arcing horn was built,and mechanisms of the arc column short circuit and arc root movement were studied.This work further analyzes the characteristics and mechanisms of the arc motion when wind speed and direction,magnetic field and the expansion angle of the electrode are varied.Arc root movement is more likely to occur at the upper electrode.There is a competitive relationship between arc expansion and the transferring effect.The effect of wind on the arc column is greater than the effect on the arc root.The magnetic field has a significant driving effect on both the arc column and the arc root.The research results provide a comprehensive experimental basis for forther probing the method of DC arc suppression,and the improvement of the arcing horn. 展开更多
关键词 grounding electrode line arcing horn DC arc dynamic physical characteristics
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Study of the Physical and Mechanical Characteristics of the Soil of Limbita 1 in the Guinean Coastal Area
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作者 Labilé Kolie Simon Pierre Lamah Alama Camara 《Open Journal of Soil Science》 2023年第7期340-354,共15页
Limbita 1 is a hilltop settlement in the rural town of khorira, the district of Dubreka. It is a land of the locality commonly called “limbita quarry”, and widely converted by bricks manufacturers of Dubreka distric... Limbita 1 is a hilltop settlement in the rural town of khorira, the district of Dubreka. It is a land of the locality commonly called “limbita quarry”, and widely converted by bricks manufacturers of Dubreka district and those of conakry area. However, no information about the characteristics of this land’s soil is yet available. The soil’s characteristics are then determined through the series of tests (granulometry, Atterberg limits, modified proctor, CBR, shear, odometric compressibility). These tests are carried out with samples derived from the site of Limbita within the area of Limbita 1. This work shows very consistent results that made it possible to deduce the very swelling nature of the soil. 展开更多
关键词 characteristics physical MECHANICAL Coastal Area ZONE
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Shear resistance characteristics and influencing factors of root-soil composite on an alpine metal mine dump slope with different recovery periods
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作者 PANG Jinghao LIANG Shen +5 位作者 LIU Yabin LI Shengwei WANG Shu ZHU Haili LI Guorong HU Xiasong 《Journal of Mountain Science》 SCIE CSCD 2024年第3期835-849,共15页
Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic cha... Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic changes and the influencing factors of the soil reinforcement effect of plant species after artificial vegetation restoration under different recovery periods.We selected dump areas of the Delni Copper Mine in Qinghai Province,China to study the relationship between the shear strength and the peak displacement of the root-soil composite on the slope during the recovery period,and the influence of the root traits and soil physical properties on the shear resistance characteristics of the root-soil composite via in situ direct shear tests.The results indicate that the shear strength and peak displacement of the rooted soil initially decreased and then increased with the increase of the recovery period.The shear strength of the rooted soil and the recovery period exhibited a quadratic function relationship.There is no significant function relationship between the peak displacement and the recovery period.Significant positive correlations(P<0.05)exists between the shear strength of the root-soil composite and the root biomass density,root volume density,and root area ratio,and they show significant linear correlations(P<0.05).There are no significant correlations(P>0.05)between the shear strength of the root-soil composite and the root length density,and the root volume ratio of the coarse roots to the fine roots.A significant negative linear correlation(P<0.05)exists between the peak displacement of the rooted soil and the coarse-grain content,but no significant correlations(P>0.05)with the root traits,other soil physical property indices(the moisture content and dry density of the soil),and slope gradient.The coarse-grain content is the main factor controlling the peak displacement of the rooted soil. 展开更多
关键词 Alpine mine dump Artificial vegetation restoration period Rooted soil Shear resistance characteristics Root traits Soil physical properties
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Functional Optical Fiber Sensors Detecting Imperceptible Physical/Chemical Changes for Smart Batteries
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作者 Yiding Li Li Wang +3 位作者 Youzhi Song Wenwei Wang Cheng Lin Xiangming He 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期268-308,共41页
The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist.Now the battery is still a“black box”,thus requiring a deep understanding of its internal st... The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist.Now the battery is still a“black box”,thus requiring a deep understanding of its internal state.The battery should“sense its internal physical/chemical conditions”,which puts strict requirements on embedded sensing parts.This paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed,focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition,electrolyte degradation,electrode-electrolyte interface dynamics to three-dimensional macro-safety evolution.The paper contributes to understanding how to use optical fiber sensors to achieve“real”and“embedded”monitoring.Through the inherent advantages of the advanced optical fiber sensor,it helps clarify the battery internal state and reaction mechanism,aiding in the establishment of more detailed models.These advancements can promote the development of smart batteries,with significant importance lying in essentially promoting the improvement of system consistency.Furthermore,with the help of smart batteries in the future,the importance of consistency can be weakened or even eliminated.The application of advanced optical fiber sensors helps comprehensively improve the battery quality,reliability,and life. 展开更多
关键词 Smart battery Advanced embedded optical fiber sensor Battery internal physical/chemical state Quality-reliability-life characteristic
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Colon transit time according to physical activity and characteristics in South Korean adults 被引量:1
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作者 Kang Ok Cho Yun Ju Jo +2 位作者 Bong Kil Song Jung Woo Oh Yeon Soo Kim 《World Journal of Gastroenterology》 SCIE CAS 2013年第4期550-555,共6页
AIM:To investigate factors contributing to the colon transit time(CTT),physical activity and characteristics were examined.METHODS:Forty-seven Korean adults(males,n=23;females,n=24) took a capsule containing 20 radioo... AIM:To investigate factors contributing to the colon transit time(CTT),physical activity and characteristics were examined.METHODS:Forty-seven Korean adults(males,n=23;females,n=24) took a capsule containing 20 radioopaque markers to measure the CTT.The subjects used an accelerometer to measure the physical activity and underwent a bioelectrical impedance analysis to determine the physical characteristics.Macro-nutrient was also surveyed.RESULTS:The mean total CTTs(TCTT) in the males and females were 8.8 and 24.7 h(P=0.002),respectively.In the male subjects,the right CTT(3.5±4.9 h vs 10.0±11.6 h,P=0.023) and recto-sigmoid CTT(4.4±4.7 vs 13.6±12.5 h,P=0.004) were significantly shorter and the total energy expenditure(637.6±44.3 kcal vs 464.3±64.9 kcal,P=0.003),total activity count(247 017±75 022 count vs 178 014±75 998 count,P=0.003),energy expenditure of light intensity(148.5±6.9 kcal vs 120.0±16.8 kcal,P=0.006),energy expenditure of moderate intensity(472.0±36.2 kcal vs 281.4±22.2 kcal,P < 0.001),fat intake(65.5±23.3 g vs 51.2±17.4 g,P=0.010),and water consumption(1714.3±329.4 g vs 1164.7±263.6 g,P=0.009) were significantly higher than in the female subjects.Regarding correlations,when adjusted for gender,fiber(r =-0.545,P < 0.001) and water intake(r =-0.257,P < 0.05) correlated significantly with the TCTT in all subjects.In addition,the body mass index(r =-0.424,P < 0.05) and fiber intake(r =-0.417,P < 0.05) in the males as well as the fiber intake(r =-0.655,P < 0.001) in the females showed significant correlations with the TCTT.CONCLUSION:The subjects showed significant gender differences in the TCTT,right CTT,and recto-sigmoid CTT.Furthermore,the intake of the fiber and water contributed to the CTT. 展开更多
关键词 COLON TRANSIT time physical activity characteristics Macro-nutrient SOUTH KOREAN
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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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3D Physical Simulation of Water Flooding Characteristics of Buried Hill Reservoir with Different Fracture Systems 被引量:1
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作者 Xiaolin Zhu Zhiqiang Meng +2 位作者 Pingzhi Gong Guanglong Li Xinran Wang 《Journal of Power and Energy Engineering》 2020年第5期1-13,共13页
In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional ... In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional physical model of fractured reservoirs is established according to the similarity criterion based on the prototype of metamorphic buried hill reservoirs in JZ Oilfield in Bohai Bay Basin. Combined with the fractured reservoir characteristics of JZ Oilfield, the water displacement characteristics of the top-bottom staggered injection-production well pattern in different fracture network mode and different fracture development degree of buried hill reservoir are studied. The experimental results show that: 1) the more serious the fracture system irregularity is, the shorter the water-free oil production period is and the lower the water-free oil recovery is. After water breakthrough of production wells, the water cut rises faster, and the effect of water flooding development is worse;2) under the condition of non-uniform fracture development, the development effect of the bottom fracture undeveloped is better than that of the middle fracture undeveloped. Water injection wells are deployed in areas with relatively few fractures, while oil wells are deployed in fractured areas with higher oil recovery and better development effect. 展开更多
关键词 METAMORPHIC Buried HILL Reservoir DIFFERENT FRACTURE SYSTEMS 3D physical Simulation Water Flooding characteristics
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Chemical and physical characteristics of quartz from gold deposits in the North China platform: relationship to gold mineralization 被引量:1
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作者 Jianzhao Yin Yang Liu Hongyun Shi 《Acta Geochimica》 EI CAS CSCD 2021年第6期998-1022,共25页
This paper seeks to identify macroscopic metallogenic mechanisms of various mineral deposits by studying microscopic typomorphic characteristics of typical minerals associated with the deposits and to reveal the mecha... This paper seeks to identify macroscopic metallogenic mechanisms of various mineral deposits by studying microscopic typomorphic characteristics of typical minerals associated with the deposits and to reveal the mechanism of lattice gold in detail by studying both physical and chemical characteristics of quartz from representative gold deposits in the North China Platform.As part of their extensive research,the authors examine the relationship between trace elements with wall rock,the ore-forming media,and gold immigration of various types of gold deposits,including their salinity,type,temperature.These are key factors to revealing the mineralization mechanism,and indicators for mineral prospecting,exploration,mining,and metallurgical technology.In order to address the questions posed,the following methods were used:field investigations of geology and sampling of the representative gold deposits,physical study and chemical analysis of quartz including,but not limited to,fluid inclusions as well as their compositions and trace elements in quartz,the unit cell parameters,electron paramagnetic resonance spectrum(EPR),and infrared spectroscopic analysis(ISA).As a result of this study,the authors observe the following key findings:unit cell parameters of quartz vary with their contents of foreign elements including gold,paragenetic stage,wall rock type,and other factors;the higher the forming temperature and the lower the gold content in quartz,the smaller the unit cell parameters,and vice versa.Additionally,the EPR absorption lines resulted from the O–Al defect center.The density of these types of hole centers increases and the EPR signal strengthens when the temperature decreases.Based on the findings,the authors conclude that lattice gold exists in quartz.Gold,in the form of Au^(+)and/or Au^(3+),entering quartz and producing an electron–hole center,namely,the O-Au hole center,makes the center produce spin resonance absorption and results in the EPR absorption peak#I.Both unit cell parameters and EPR of quartz can potentially be used in mineral prospecting,relative ore-forming temperature determination,and grade control during mining. 展开更多
关键词 physical and chemical characteristics QUARTZ Gold mineralization Unit cell parameter Electron paramagnetic resonance spectrum Infrared spectrum
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Effects of Varieties and Cooking Methods on Physical and Chemical Characteristics of Cooked Rice 被引量:1
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作者 Merynda Indriyani SYAFUTRI Filli PRATAMA +1 位作者 Friska SYAIFUL Achmad FAIZAL 《Rice science》 SCIE CSCD 2016年第5期282-286,共5页
To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each c... To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each combination of the factors was repeated three times. The first factor was rice variety(Ciherang and Ciliwung) and the second factor was the cooking method(stovetop, boiling and steaming, and rice cooker). Results showed that Ciherang and Ciliwung varieties were classified into slender grain rice type with yellowred color. The amylose content of Ciherang was classified as moderate, while the amylose content of Ciliwung classified as low. The most abundant amino acid contained in Ciherang and Ciliwung varieties was glutamic acid. Statistical analysis showed that cooking method had significant effects on texture, lightness, chroma, hue and moisture content of cooked rice. Rice cooked with liwet method had the lowest texture value, lowest lightness value, highest chroma value, and highest moisture content. 展开更多
关键词 physical and chemical characteristic cooking method rice variety amino acid
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Physical Properties of Crushed Air-cooled Blast Furnace Slag and Numerical Representation of Its Morphology Characteristics 被引量:1
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作者 王爱国 邓敏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第5期973-978,共6页
Physical properties and geometrical morphologies of crushed air-cooled blast furnace slag (SCR) and crushed limestone (LCR) were comparatively investigated. The shape, angularity, surface texture and internal pore... Physical properties and geometrical morphologies of crushed air-cooled blast furnace slag (SCR) and crushed limestone (LCR) were comparatively investigated. The shape, angularity, surface texture and internal pore structure of aggregate particles for different size and gradation were numerically represented by sphericity (ψ) and shape index (SI), angularity number (AN), index of aggregate particle shape and texture (IAPST), porosity and pore size, respectively. The results show that SCR is a porous and rough aggregate. Apparent density, void, water absorption and smashing index of SCR are obviously higher than those of LCR with the same gradation, respectively. However, bulk density of SCR is lower than that of LCR with the same gradation. SI, AN, IAPST and porosity of SCR are obviously higher than those of LCR with the same gradation, respectively. The smaller particle size of SCR, the larger of its AN, IAPST and porosity. 展开更多
关键词 crushed air-cooled blast furnace slag crushed limestone physical property morphology characteristic numerical representation
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Mass Modeling of Sweet Cherry (<i>Prunus avium</i>L.) Fruit with Some Physical Characteristics
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作者 Feizollah Shahbazi Satar Rahmati 《Food and Nutrition Sciences》 2013年第1期1-5,共5页
Horticultural crops with the similar weight and uniform shape are in high demand in terms of marketing value that used as food. The knowledge on existing relationship among the mass, length, width, thickness, volume a... Horticultural crops with the similar weight and uniform shape are in high demand in terms of marketing value that used as food. The knowledge on existing relationship among the mass, length, width, thickness, volume and projected areas of fruits is useful for proper design of grading machines. A part of this research was aimed to present some physical properties of cherry fruit. In addition, in this study the mass of cherry fruit was predicted with using different physical characteristics in four models including: Linear, Quadratic, S-curve, and Power. According to the results, all properties considered in the current study were found to be statistically significant at the 1% probability level. The best and the worst models for mass prediction of cherry fruit were based on geometric mean diameter and thickness of the cherry with determination coefficients (R2) of 0.938 and 0.484, respectively. At last, mass model of cherry fruit based on first projected area from economical standpoint is recommended. 展开更多
关键词 SWEET CHERRY physical characteristics MASS Prediction
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Studies on Dynamic of Physical and Chemical Characteristics of Water in GaoBaZhou Reservoir after Filter-feeding Fish's Multiplication and Stocking
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作者 CAI Yu LIU Zhi-guo +5 位作者 CAI Yan-zhi WAN Song-tong XIA Jian-jun LI Xian-cai LEI Xiao-zhong WANG Liang 《Animal Husbandry and Feed Science》 CAS 2012年第5期231-235,共5页
[ Objective] The aim was to provide scientific basis for purifying water quality, ecological restoration and fishery breeding of GaoBaZhou reservoir multiplication and stocking. [ Method] Monitoring of normal water ph... [ Objective] The aim was to provide scientific basis for purifying water quality, ecological restoration and fishery breeding of GaoBaZhou reservoir multiplication and stocking. [ Method] Monitoring of normal water physical, chemical characteristics and different number of data of GaoBaZhou reservoir was conducted in 2010 and 2011 after different amount of filter-feeding fishes stocking in this reservoir. [ Result] The water physical and chemical factors TN, NO2, NO3-N-N, TP and COD, Chl. a in 2011 were significantly less than 2010, 2011 month average 1.389 mg/L, 0.039 6 rng/L, 1.211 7 mg/L, 0.137 3 mg/L, 16.191 mg/L, 10.226 8 mg/m3, 2010 month average 1.659 mg/L, 0.066 2 mg/L, 1.472 9 mg/L, 0.099 9 rag/L, 18.314 8 mg/L, 14.917 8 mg/L. The calculation results of TSIM showed that 2011 reservoir eutrophication TSIM were less than 2010, up to 53.78 and 57.36. E Coaclusion: The whole reservoir area revealed mild eutrophication (the TSIM 〉 53), and it suggested that the filterfeeding fishes amount could be increased in the reservoir. 展开更多
关键词 GaoBaZhou reservoir Multiplication and stocking physical and chemical characteristics Purification effect
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Contribution to Comparative Study of Physical-Chemical Characteristics of Diack Basalt and Bandia Limestone for Use in Railway Engineering 被引量:3
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作者 Abdoulaye Diedhiou Libasse Sow Adama Dione 《Geomaterials》 2020年第2期25-34,共10页
This paper presents a comparative study of Physical-Chemical characteristics of Limestone and Basalt (from Senegalese quarries). First, chemical tests show that Basalt is richer in silica 51.59% versus 2.84% for Limes... This paper presents a comparative study of Physical-Chemical characteristics of Limestone and Basalt (from Senegalese quarries). First, chemical tests show that Basalt is richer in silica 51.59% versus 2.84% for Limestone. Basalt is made up of silica minerals and essentially carbonated minerals with a CaO percentage of 50.05%. Chemical results also show that Basalt is richer in iron 12.71% versus 0.44% for Limestone. Finally, they revealed a fire loss of 40.91% for Limestone and 2.44% for Basalt. Second, physical analysis results show that Diack Basalt has the best characteristics with a flattening coefficient of 5% between 5% and 20%;the percentage of pollutants is 0.36% less than 1%;the Los Angeles coefficient is 12.21% below 15, while Bandia Limestone gives a flattening coefficient of 3%;the Los Angeles coefficient of 40.17% and the percentage of pollutant (2.4%) well above 2%. It is noted that the percentage of Limestone pollutant is too high. These important results show the net advantage of Basalt compared to Limestone in terms of physical-chemical characteristics. 展开更多
关键词 BALLAST Railways BASALT LIMESTONE physical-Chemical characteristIC
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Case Analysis on Physical Characteristics of Autumn Cumulus-stratus Mixed Cloud in Shandong Province
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作者 WANG Jun1,ZHOU Yu-quan2,GONG Dian-li1,SHENG Ri-feng1,ZHOU Li-ming1 1.Weather Modification Office of Shandong Government,Jinan 250031,China 2.Chinese Academy of Meteorological Science,Beijing 100081,China 《Meteorological and Environmental Research》 CAS 2011年第10期74-77,90,共5页
[Objective] The aim was to analyze physical structures of mixed cloud in autumn in Shandong.[Method] By dint of Doppler radar data,the raindrop spectrum data observed by laser spectrometer,second sounding data of L-ba... [Objective] The aim was to analyze physical structures of mixed cloud in autumn in Shandong.[Method] By dint of Doppler radar data,the raindrop spectrum data observed by laser spectrometer,second sounding data of L-band,satellite retrieval data,and other general information,the physical structures of mixed cloud in autumn on August 29,2009 were discussed.[Result] This was a typical precipitation process of mixed cloud,and the main precipitation process lasted for 10 hours.Rainfall intensity was ups and downs obviously with the time.The maximum rainfall intensity was 6.5 mm/h and the normal of that was less than 3.0 mm/h.The rain concentrations were between 5 and 300,and the raindrop spectrum was mainly of bimodal or multimodal peaks.It showed that the precipitating cloud was mainly cold cloud and the development of warm layers was not well according to the vertical structure of clouds which was analyzed by second sounding data.It showed by the Doppler radar data that the whole precipitation process was divided into four stages:prior period and initial,maturing,declining stages for precipitation,which the echo structure of different stages was quite different.[Conclusion] The study laid theoretical basis for the study on precipitation mechanism and artificial precipitation potential. 展开更多
关键词 Cumulus-stratus mixed cloud Cloud physical characteristics Raindrop spectrum Doppler radar data China
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Living Model Based on Changing Physical and Mental Characteristics and Needs of the Elders
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作者 LI Xiaoyun DING Yilei 《Journal of Landscape Research》 2015年第1期3-4,共2页
The ageing of society has been considered as one of the three major social problems in the twentyfirst century. Since 2000, China has entered the ageing society formally, and become one of the earliest developing coun... The ageing of society has been considered as one of the three major social problems in the twentyfirst century. Since 2000, China has entered the ageing society formally, and become one of the earliest developing countries that witness the population ageing, and also the countries with the largest ageing population in the world. Problems for supporting the aged have become crucial social problems of China. This paper, on the basis of analyzing changing physical and mental characteristics and needs of the elders, proposed different living models such as living together, living alone, living close, and social nursing facilities. 展开更多
关键词 Ageing Living model physical and mental characteristics Needs
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Analysis on the Physical Characteristics of High-level Football Players
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作者 Yijun Chen 《教育研究前沿(中英文版)》 2019年第4期338-341,共4页
This article uses the literature data method and literature review method to review and collect relevant literature,and summarizes and analyzes the representative views on domestic physical fitness research.After summ... This article uses the literature data method and literature review method to review and collect relevant literature,and summarizes and analyzes the representative views on domestic physical fitness research.After summarizing and summarizing,it is considered that:physical energy is the basic athletic ability of the human body expressed through physical qualities such as strength,speed,endurance,coordination,flexibility,and sensitivity,and is an important component of athletes'athletic ability.The level of physical fitness is closely related to the morphological characteristics of the human body and the functional characteristics of the human body.The morphological characteristics of the human body are the structural basis of its physical fitness,and the functional characteristics of the human body are its biological functional basis.As the basic ability of athletes,physical fitness is an important factor of athletes'competitive ability.Each competitive sport has its own specific physical characteristics and training rules and methods.Grasping these laws has very important guiding significance for the improvement of athletes'sports level. 展开更多
关键词 physical Fitness Athletic Ability High Level Football Player physical characteristics
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Research on the calibration method of precipitation micro- physical characteristics sensor 被引量:1
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作者 SHU Xiaojian GAO Taichang +1 位作者 LIU Xichuan HU Shuai 《Instrumentation》 2015年第3期55-64,共10页
In order to diminish the effect of the ambient light and CCD pixel non-uniformity to the Precipitation Micro-physical Characteristics Sensor,a modified calibration scheme was designed and calibration experiments in su... In order to diminish the effect of the ambient light and CCD pixel non-uniformity to the Precipitation Micro-physical Characteristics Sensor,a modified calibration scheme was designed and calibration experiments in sunny,cloudy,night,different location of sample space were carried out. Firstly,the characteristics of particle images which affected by ambient light and different location of sample space were analyzed. Secondly,the relevance betw een particle image features and parameters of image processing were discussed. Finally,the parameter setting scheme were determined,the radium of median filtering algorithm is 3 pixels,the defocusing radius of point spread function( PSF) is 7 pixels,the radium of erosion is 3 pixels,and the binary threshold is obtained from the Area-thresh relationship. The results show that the new scheme could deal with the image calibration well,the average errors of equivolumetric diameter was 0. 041 mm with standard deviation of 0. 115 mm,and the average errors of the axis ratio was 0. 011 with standard deviation of 0. 085. The new scheme works well in the field observation too,the observed axis ratio is consistent with the empirical relationship that proposed by Beard. The relative error of accumulation precipitation is-3. 06% after calibration,w hich is improved 1. 94% low er than the initial one without calibration. 展开更多
关键词 PRECIPITATION micro-physical characteristics SENSOR calibration scheme PARTICLE image FEATURES thres
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Physical and chemical characteristics and research of total suspended particles in Xi'an and Nanjing
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作者 DONG Zhen ZHENG You-fei 《Journal of Environmental Science and Engineering》 2007年第1期62-68,共7页
关键词 化学特性 总悬浮颗粒 物理 南京 西安 总悬浮微粒 大气气溶胶 气溶胶粒子
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Studies on the effects of bio-organic fertilizer on the physical and chemical characteristics of soil and the yield of cassava*
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作者 LUO Xing-lu CEN Zhong-yong XIE He-xia PAN Ying-hua LIAO Cheng SHAO Zhi-fang CHEN Hui-lin 《Journal of Life Sciences》 2008年第1期27-36,共10页
关键词 生物有机肥 土壤肥力 木薯 产量 化学特性 物理 土壤脲酶活性 有机质含量
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