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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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Effects of seven different companion plants on cucumber productivity, soil chemical characteristics and Pseudomonas community 被引量:5
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作者 CHANG Chun-ling FU Xue-peng +2 位作者 ZHOU Xin-gang GUO Mei-yu WU Feng-zhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2206-2214,共9页
Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study,... Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study, seven different plant species were selected as companion plants for testing their effects on cucumber productivity. The effects of different companion plants on changes in soil chemical properties such as electrical conductivity (EC) and contents of essential nutrients as well as the structure and abundance of the soil Pseudomonas community were evaluated. The results showed a higher cucumber yield in the wheat/cucumber companion system than that in the cucumber monocultured and other companion cropping systems. The lowest phosphorus (P) and potassium (K) contents in the soil were found in the cucumber monocultured system, and the highest NO3+-N and NH4*-N contents were observed in the rye/cucumber companion system. PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR analysis showed that the trifolium/cucumber companion system increased the diversity of the soil Pseudomonas community, while the chrysanthemum/cucumber companion system increased its abundance. Interestingly, plant-soil feedback trials revealed that inoculating the soil of the wheat/cucumber companion system increased the growth of cucumber seedlings. In conclusion, the effects of different companion plants on cucumber productivity, soil chemical characteristics and the soil Pseudomonas community were different, and wheat was a more suitable companion plant for increasing cucumber productivity. In addition, the altered microbial community caused by companion cropping with wheat contributed to increased cucumber productivity. 展开更多
关键词 CUCUMBER companion plants soil chemical characteristics Pseudomonas community
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Analysis on the Chemical Characteristics of Shallow Groundwater and Causes of Formation in the Area around Poyang Lake 被引量:5
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作者 YANG Tao WANG Shi-jie 《Meteorological and Environmental Research》 CAS 2011年第9期77-80,共4页
[Objective] The study aimed at analysing the chemical characteristics of shallow groundwater and causes of formation around Poyang Lake area. [Method] The quality of shallow groundwater under seven counties or cities ... [Objective] The study aimed at analysing the chemical characteristics of shallow groundwater and causes of formation around Poyang Lake area. [Method] The quality of shallow groundwater under seven counties or cities around Poyang Lake was investigated in 2010, and compared different regions from salinity, hardness, conductivity, hydrochemistry types and so forth, so as to reveal the status quo, change characteristics and reasons of shallow groundwater. [Result] Except for pH, other water quality indicators of shallow groundwater around Poyang Lake were better, attaining Class I water quality standards. Among these regions, the salinity, hardness, conductivity, Na+, K+, Ca2+, Mg2+, Cl- and HCO-3 concentration of shallow groundwater in Nanchang city were up to the maximum values, while pH and SO2-4 concentration were the highest in Duchang County; Mg2+ concentration and pH were the lowest in Poyang County, and hardness, K+, Ca2+, SO2-4 and Cl- concentration in Yongxiu County reached the minimum values, while Na+ concentration, salinity and conductivity were the lowest in Jinxian County. In addition, the better quality of groundwater around Poyang Lake was closely related to the low level of economic development in Jiangxi Province. Meanwhile, many water quality indices in Nanchang City reached the maximum values, and even tended to Class Ⅱ water quality standards, which resulted from the high level of economic development and decisive role of human activities. [Conclusion] The research could provide references for the establishment of management strategies for regional shallow groundwater. 展开更多
关键词 Poyang Lake Shallow groundwater chemical characteristics China
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Electrokinetic chemical characteristics of humic and dannic acids effecting on the natural water and its coagulation 被引量:1
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作者 Qu Jiuhui Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第1期71-79,共9页
Taking streaming current(SC)as the electrokinetic parameter,this paper demon- strated the electrokinetic chemical characteristics of humic and dannic acids(HA and DA)in sus- pensions including turbid water,coagulated ... Taking streaming current(SC)as the electrokinetic parameter,this paper demon- strated the electrokinetic chemical characteristics of humic and dannic acids(HA and DA)in sus- pensions including turbid water,coagulated water and HA or DA contained water.Accordingly, the studies were carried out for determining the relationship between streaming current and zeta po- tential ζ(expressed by eleetrophoretie mobility EM)in above water conditions.In addition,the mechanisms of HA effecting on streaming current within or after coagulant addition and the elec- trokinetic detection principles for HA or DA were also investigated on experiments and theoretical analysis.The results indicated that the change of SC like ζ presented meaningful information con- cerning the degree for destabilization of a particulate suspension,and HA or DA in water could re- markably decrease the effect of inorganic coagulant upon streaming current,which is in accordance with their influence on coagulation. 展开更多
关键词 electrokinetic chemical characteristics humic acid dannic acid natural water.
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Anatomical and Chemical Characteristics of a Rolling Leaf Mutant of Rice and Its Ecophysiological Properties 被引量:1
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作者 BAI Lei DUAN Zhuang-qin +3 位作者 WANG Jun-min AN Li-zhe ZHAO Zhi-guang CHEN Kun-ming 《Rice science》 SCIE 2008年第3期201-208,共8页
The anatomical and chemical characteristics of a rolling leaf mutant (rlm) of rice (Oryza sativa L.) and its ecophysiological properties in photosynthesis and apoplastic transport were investigated. Compared with ... The anatomical and chemical characteristics of a rolling leaf mutant (rlm) of rice (Oryza sativa L.) and its ecophysiological properties in photosynthesis and apoplastic transport were investigated. Compared with the wild type (WT), the areas of whole vascular bundles and xylem as well as the ratios of xylem area/whole vascular bundles area and xylem area/phloem area were higher in rim, whereas the area and the width of foliar bulliform cell were lower. The Fourier transform infrared (FTIR) microspectroscopy spectra of foliar cell walls differed greatly between rim and WT. The rim exhibited lower protein and polysaccharide contents of foliar cell walls. An obvious reduction of pectin content was also found in rim by biochemical measurements. Moreover, the rate of photosynthesis was depressed while the conductance of stoma and the intercellular CO2 concentration were enhanced in rim. The PTS fluorescence, which represents the ability of apoplastic transport, was 11% higher in rim than in WT. These results suggest that the changes in anatomical and chemical characteristics of foliar vascular bundles, such as the reduction of proteins, pectins, and other polysaccharides of foliar cell walls, participate in the leaf rolling mutation, and consequently lead to the reduced photosynthetic dynamics and apoplastic transport ability in the mutant. 展开更多
关键词 RICE rolling leaf mutant anatomical characteristics chemical characteristics apoplastic transport ecophysiological property Fourier transform infrared microspectroscopy
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Chemical, Nutritional and Organoleptical Characteristics of Orange-Based Formulated Low-Calorie Jams 被引量:1
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作者 Rafeek M. Abolila Hassan Barakat +1 位作者 Hassan A. El-Tanahy Hamdy A. El-Mansy 《Food and Nutrition Sciences》 2015年第13期1229-1244,共16页
Twelve low-calorie orange-based formulated jams were prepared mainly from orange, pumpkin and papaya, and then sweetened using fructose (F), stevioside (St) and sucralose (Su). The nutritional value of formulated jams... Twelve low-calorie orange-based formulated jams were prepared mainly from orange, pumpkin and papaya, and then sweetened using fructose (F), stevioside (St) and sucralose (Su). The nutritional value of formulated jams was estimated after the approximate chemical composition and total soluble solid have been determined. The effect of storage on total phenolic compounds, antioxidant capacity, carotenoids content and vitamin C was investigated. Organoleptical attributes of prepared low-calorie jams were done as well. Results indicated that the nutritive value [kcal 100 g–1 fw] ranged from 88.10 ± 0.60 to 164.34 ± 0.41;total phenol content (TPC, mg GAE 100 g–1 fw] ranged from 188.52 ± 2.45 to 411.79 ± 3.3;the antioxidant capacity (μmol TE g–1 fw) ranged from 14.57 ± 0.86 to 32.39 ± 1.19;total carotenoids [mg 100 g–1 fw] ranged from 115.20 ± 5.66 to 204.33 ± 4.21;vitamin C [mg 100 g fw] ranged from 8.94 ± 1.07 to 28.77 ± 4.46;total soluble solids [Brix] ranged from 22.53 ± 0.05 to 43.37 ± 0.13. Jams storage for a period of 12 months at room temperature led to a decrease in vitamin C content, TPC, antioxidant capacity, while total soluble solids (TSS) and carotenoids increased during storage. The results of organoleptical attributes showed that the formulas O11, O1 had the highest score of color and odor respectively while O7 recorded maximum score for taste, texture and bitterness respectively. Statistical analysis showed that storage intervals and treatments had a significant (p < 0.05) effect on sensory quality of diet jam. The organoleptical characteristics were affected with the extension of shelf-life. Addition of stevioside and sucralose to formulate the low-calorie jam increased total phenol and antioxidant capacity, improved color, taste and produced targeted low-calorie jams. The use of sweeteners such as fructose, sucralose and stevioside in the manufacture of orange diet jam was shown to be satisfactory, resulting in low-calorie jams, improved the quality and could be produced commercially. 展开更多
关键词 Low-Calorie Jam chemical NUTRITIONAL Organoleptical characteristics
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Potential Use of Selected Sweetpotato (<i>Ipomea batatas</i>Lam) Varieties as Defined by Chemical and Flour Pasting Characteristics 被引量:1
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作者 Agnes Nabubuya Agnes Namutebi +2 位作者 Yusuf Byaruhanga Judith Narvhus Trude Wicklund 《Food and Nutrition Sciences》 2012年第7期889-896,共8页
Chemical and functional properties of ten sweetpotato varieties were investigated. The sweetpotato were of various flesh colours which included orange, yellow, cream and white with dry matter content ranging from 30.2... Chemical and functional properties of ten sweetpotato varieties were investigated. The sweetpotato were of various flesh colours which included orange, yellow, cream and white with dry matter content ranging from 30.2% - 39.2%. The sweetpotato varieties varied significantly (p < 0.05) in total amylase activity, total starch and amylose content whose value ranges were 0.256 - 0.570 mg/ml/min 68.4% - 73.6%, 16.2% - 23.4% respectively. The pH of flours from the different sweetpotato varieties ranged from 6.01 - 6.64. The pasting behaviours of the sweetpotato flours also showed significant differences (p < 0.05) in the individual parameters (peak time, pasting temperature, peak viscosity, trough viscosity, final viscosity, breakdown and setback) among the different varieties. The results revealed the influence of variety on the chemical composition of sweetpotato and their pasting properties. Correlations were also revealed among different components of the sweetpotatoes which would be a basis in selection of the varieties for processing into different products. 展开更多
关键词 SWEETPOTATO chemical Properties PASTING characteristics
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Nutritional, Chemical and Organoleptical Characteristics of Low-Calorie Fruit Nectars Incorporating Stevioside as a Natural Sweetener 被引量:1
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作者 Hassan Barakat Abdulaziz Al-Furaydi +1 位作者 Abdulelah Al-Harbi Ali Al-Shedookhi 《Food and Nutrition Sciences》 2017年第1期126-140,共15页
The study is aiming at preparation of low-calorie fruit nectars for diabetes and weight maintaining approaches as well as consumer satisfaction. Therefore, twenty low-calorie fruit-based formulated nectars were prepar... The study is aiming at preparation of low-calorie fruit nectars for diabetes and weight maintaining approaches as well as consumer satisfaction. Therefore, twenty low-calorie fruit-based formulated nectars were prepared mainly from orange, pomegranate, guava and mango pulps which sweetened with sucrose or sucrose— replaced at 25%, 50%, 75% and 100% using stevioside. Primitively, the yield of fresh fruits had been calculated. Consequently, nutritional, chemical and organoleptical characteristics of prepared fruit nectars have been determined. Results indicated that total solids content was in range of 5.57% - 13.20%, 9.90% - 14.37%, 8.25% - 13.27% and 8.25% - 16.50% for orange, pomegranate, guava and mango nectars, respectively. Dependently, caloric value resulted 21.57 to 51.08, 38.31 to 55.62, 31.93 to 51.37 and 31.93 to 63.86 kcal 100 g-1 fw for orange, pomegranate, guava and mango nectars, respectively. Total phenols content [TPC, mg GAE 100 g-1 dw] ranged from 665.12 to 747.41, 1180.42 to 1319.47, 742.54 to 848.27 and 418.01 to 472.42 for orange, pomegranate, guava and mango nectars, respectively. The antioxidant capacity by DPPH method [μmol TE g-1 dw] ranged from (20.79 to 26.51), (47.13 to 56.56), (60.68 to 69.25) and (8.39 to 13.32) for orange, pomegranate, guava and mango nectars, respectively. Total carotenoids [mg 100 g-1 dw] were the highest in mango nectars ranged from (102.99 to 110.52) in mango nectar with 100% sugar and mango nectar with 100% stevioside, respectively. Anthocyanins content recorded 6.14 mg 100 g-1 dw in pomegranate nectar with 100% sugar, while increased to be 9.01 mg 00 g-1 dw in pomegranate nectar with 100% stevioside. Ascorbic acid [mg 100 g fw] ranged from 23.41 to 27.53, 15.73 to 18.32, 25.72 to 30.87 and 18.07 to 20.98 for orange, pomegranate, guava and mango nectars, respectively. The results of organoleptical attributes showed no effect of sugar substituting by stevioside on color, odor and mouth feel. The most dramatic effect of sugar substituting had been observed on taste, bitter after taste and the overall acceptability of prepared nectars with high substitution levels. Practically, using stevioside to produce low-calorie nectars was shown to be satisfactory up to 50% - 75% substituting level, resulting low-calorie nectars and could be applied commercially. 展开更多
关键词 Low-Calorie Nectar chemical NUTRITIONAL Organoleptical characteristics
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Physicochemical Characteristics of Calamondin(Citrus microcarpa)from Hainan 被引量:1
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作者 Yi ZOU Hongjian ZHANG Lianhe ZHENG 《Asian Agricultural Research》 2020年第12期58-62,共5页
Some physicochemical characteristics of calamondin(Citrus microcarpa)from Hainan were determined in this study.The mean length,width,and thickness of calamondin were(2.763±0.262),(2.721±0.189),and(2.684±... Some physicochemical characteristics of calamondin(Citrus microcarpa)from Hainan were determined in this study.The mean length,width,and thickness of calamondin were(2.763±0.262),(2.721±0.189),and(2.684±0.201)cm,respectively.The average values for geometric mean diameter,sphericity,fruit shape index,mass,surface area,volume,true density,bulk density and porosity were(2.721±0.196)cm,(98.79±5.149)%,(101.64±7.609)%,(11.18±2.149)g,(23.36±3.362)cm2,(11.16±2.115)cm3,(1.00±0.060)g/cm3,0.44 g/cm3,and(56.40±0.027)%,respectively.The mean edible part,juice rate,and soluble solids were(85.77±3.53),(48.36±4.20),and(7.86±0.09)%,respectively.The total flavonoids,pectin,limonin,reducing sugar and volatile oil contents of the peel were 1.00,7.14,0.51,5.98,and 4.25%,respectively.The total flavonoids,pectin,limonin and reducing sugar contents of the pulp were 0.02,5.04,0.03 and 4.56%,respectively.The total flavonoids,total acid,reducing sugar and vitamin E contents of the juice were 0.11,6.74,0.37%,and 1.68 mg/kg,respectively,while the content of vitamins A,B1,B2,B3,B6,and D in the juice was very low.The seeds had limonin,reducing sugar and oil contents of 0.46,1.39,and 30.46%,respectively.The vitamin B2,B3,B6 and E contents of the fruit residue were 44.83,19.31,17.55,and 15.72 mg/kg,respectively.The amino acid profile of the residue included aspartic acid,glutamate,cystine,serine,glycine,histidine,arginine,threonine,alanine,proline,tyrosine,valine,methionine,isoleucine,leucine,phenylalanine and lysine,with respective contents of 4.42,1.81,2.10,0.78,0.59,0.20,0.72,0.160.67,3.650.50,0.67,0.59,1.00,0.76,0.57 and 0.91 g/kg. 展开更多
关键词 Hainan calamondin Physical characteristic chemical characteristic Nutrient content
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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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Effect of Garlic Straw on Physical and Chemical Characteristics of Continuous Cropping Soil and Root Activity of Tomato in Solar Greenhouse 被引量:1
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作者 刘素慧 徐金强 +2 位作者 尉辉 刘庆涛 徐峥 《Agricultural Science & Technology》 CAS 2016年第6期1349-1354,共6页
Taking tomato "Kate two" as the experimental material, the effects of different dosage of garlic straw on physical and chemical characteristics of continuous cropping soil and root activity of tomato in solar greenh... Taking tomato "Kate two" as the experimental material, the effects of different dosage of garlic straw on physical and chemical characteristics of continuous cropping soil and root activity of tomato in solar greenhouse were studied. The results showed that after applying with garlic straw, maximal and minimal temperatures in 0-15 cm soil layers were directly proportional to the amount of returned garlic straw, which were 2.39 ℃ and 1℃ higher than that of the control respectively. The unit weight was decreasing upon the amount of applied garlic straws of soils in different depths, but the porosity of soil was increasing. For example, unit weight and porosity changed the most significantly in soils in the depths of 0-10 cm, which went down by 6.71% and 6.18%, respectively. Besides, garlic straw returning to field improved soil pH, reduced soil conductivity and soil acidification and relieved soil secondary salinization, especially in 0-20 cm soil layers. In addition to that, the application of garlic straw increased the root activity of tomato (max 31.45%), and delayed root system senescence in late stage. Therefore, garlic straw returning could improve the physical and chemical characteristics of soil by succession planting and root activity of tomato in solar greenhouse. 展开更多
关键词 Garlic Crop straw TOMATO Physical and chemical characteristics Root activity
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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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Effects of Microbial Fertilizer on Growth Characteristics of Facility Tomato and Chemical Properties of Acidic soil 被引量:1
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作者 Peiping ZHANG Zhidian WANG Yao SUN 《Agricultural Biotechnology》 CAS 2018年第2期55-57,70,共4页
[Objectives]This study was conducted to discuss the possibility of applying microbial fertilizer to production of facility tomato,so as to determine rational application rate for facility tomato.[Methods]A field exper... [Objectives]This study was conducted to discuss the possibility of applying microbial fertilizer to production of facility tomato,so as to determine rational application rate for facility tomato.[Methods]A field experiment was carried out to investigate the effects of the application of microbial fertilizer onto acidic soil on yield,quality and soil chemical properties of facility tomato.[Results]Yield of facility tomato was improved after the application of microbial fertilizer.Treatment ABA-2 showed the highest yield,which was higher than the CK by 7.98%.On the basis of conventional fertilization,the combined application with microbial fertilizer could promote growth and development of tomato,and could significantly improve fruit weight,and Vc,soluble solid and lycopene contents.Furthermore,the microbial fertilizer could remarkably improve soil p H,alkali-hydrolyzale nitrogen,available phosphorus and rapidly available potassium contents.[Conclusions]The application of microbial fertilizer at 80 kg/667 m^(2) has better effects on tomato growth and development and soil status. 展开更多
关键词 Microbial fertilizer Facility tomato Growth characteristics Soil chemical propertiesHome
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CHEMICAL CHARACTERISTICS OF FOUR KINDS OF WATER IN THE RONGBUK GLACIER BASIN, MOUNT QOMOLANGMA
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作者 秦翔 秦大河 《Chinese Geographical Science》 SCIE CSCD 1999年第3期82-86,共5页
The chemistry of water samples collected in May of 1997 from snow, lakes, rivers, and spring on the north side of Mt. Qomolangma is reported. The pH value is between 7.35-8.52, the order of which is: lake water>riv... The chemistry of water samples collected in May of 1997 from snow, lakes, rivers, and spring on the north side of Mt. Qomolangma is reported. The pH value is between 7.35-8.52, the order of which is: lake water>river water>snow. All the samples are alkalinity. The pH values of the surface snow samples are relatively higher than the other China’s glacial regions. The conductivity of the samples is low, varying between 34.8-194?μs/cm. The conductivity values and total concentrations of the samples on the same glacier usually increase with decreasing altitude, but ones of the surface snow samples are converse for topographical causes. The anions are determined, the SO 2- 4 concentration is the highest in river and lake samples; in the surface snow samples, the Cl - concentration is the highest. Among the cations of all the samples, the Ca 2+ concentration is the highest. The relationships between SO 2- 4, Mg 2+ , F -, Ca 2+ , conductivity and the total concentrations show the increasing trend. On the other side, the conductivity, F -, Ca 2+ , the total concentration, SO 2- 4 and Mg 2+ of the river water samples all increase with decreasing altitude. 展开更多
关键词 chemical characteristics Rongbuk GLACIER Mt. Qomolangma
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CHEMICAL CHARACTERISTICS OF THE COASTAL SEA OFF TIANHENG ISLAND
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作者 徐明德 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1994年第3期228-235,共8页
Chemical characteristics of the coastal sea off Tianheng Island were investigated from May 1990 toFebruary 1991 in this study which included distribution pattern,seasonal variability and the controlling fac-tors of ox... Chemical characteristics of the coastal sea off Tianheng Island were investigated from May 1990 toFebruary 1991 in this study which included distribution pattern,seasonal variability and the controlling fac-tors of oxygen,pH,nutrients.The rich nutrient salt content is suited for phytoplankton growth andmariculture.The coastal sea waters is of good quality based on the national standard of seawater qual-ity in terms of pH,oxygen,and nutrients,the main controlling factors for which in the investigated seaarea are hydrographic(salinity,temperature,river runoff,etc.),biological(photosynthesis of plankton),andanthrogenic(fertilizing in the nearby land and sea). 展开更多
关键词 chemical characteristics COASTAL SEA Tianheng Island.
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Chemical characteristics of precipitation and wet deposition of major ions in Liaozhong County of Liaoning Province,Northeast China
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作者 Houfeng Liu Yizhen Chen +1 位作者 Shanzhong Qi Chunnan Zhang 《Chinese Journal of Population,Resources and Environment》 2013年第3期210-217,共8页
The chemical characteristics of precipitation were analyzed based on the chemical composition of principal ionic within acid rain(from February 2007 to January 2008)of Liaozhong Meteorological Station located in Malon... The chemical characteristics of precipitation were analyzed based on the chemical composition of principal ionic within acid rain(from February 2007 to January 2008)of Liaozhong Meteorological Station located in Malong Village in Liaozhong County of Northeast China,meteorological conditions on the corresponding period ground,and variation of several air pollutants concentration.The results indicated that:(1)The precipitation average pH value of all samples was4.76;the frequency of acid rain during the observation period was 70.7%;the frequency was 82.8%in summer and autumn.(2)In the chemical composition of precipitation,the primary anions were SO_4^(2-)and NO_3^-;the primary cations were NH_4^+and Ca^(2+).(3)All concentration of anions was higher in summer and winter,but relatively low in spring and autumn.This showed that the relationship between regional rainfall acidification and pollution was not significant.(4)Rainwater acidity and nearly floor gaseous pollution concentration were different from each other,and pH and NO_x,CO,NO_2 and O_3concentrations showed significant negative correlation,but was not obvious with SO_2 concentration.However,the pH and alkaline pollutants,such as particulate,was positively correlative. 展开更多
关键词 PRECIPITATION ACID RAIN chemical characteristics Liaozhong COUNTY
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Physico-Chemical and Bacterial Characteristics of Groundwater and Surface Water Quality in the Lagbe Town: Treatment Essays with <i>Moringa oleifera</i>Seeds
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作者 K. Jacques Fatombi T. Angèle Ahoyo +1 位作者 Odilon Nonfodji Taofiki Aminou 《Journal of Water Resource and Protection》 2012年第12期1001-1008,共8页
The river water and groundwater from Lagbe town in Benin Republic were collected and analyzed for physical, chemical and microbiological parameters. The surface water samples were treated with alum, Moringa oleifera s... The river water and groundwater from Lagbe town in Benin Republic were collected and analyzed for physical, chemical and microbiological parameters. The surface water samples were treated with alum, Moringa oleifera seeds powder and the combination of alum and Moringa oleifera seeds. The jar-test essays were carried out with two water samples at initial turbidities 7.2 NTU and 14.4 NTU. The water samples analyzed are fairly mineralized (conductivity varies between 166 and 687 μS/cm), enough soft and contain the nitrate (104 mg/L for W4 sample). They are greatly polluted by pathogenic microorganisms such as Escherichia coli, Klebsiella, Enterococcus, Vibrio, Serratia. The optimal dosages of Moringa are 96 mg/L and 80 mg/L respectively. We have observed a reduction of 60% of turbidity and a substantial remove of all pathogenic microorganisms after water treatment with Moringa oleifera seeds. For the combination treatment, 93% of initial turbidity and 92% of initial concentration of organic matter in the sample E2 were eliminated. The pH remained almost constant during the treatment. 展开更多
关键词 GROUNDWATER Surface WATER Moringa oleifera WATER TREATMENT Physic chemical BACTERIAL characteristics
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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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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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Chemical Characteristics and Anticoagulant Activities of Two Sulfated Polysaccharides from Enteromorpha linza (Chlorophyta)
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作者 QI Xiaohui MAO Wenjun +4 位作者 CHEN Yin CHEN Yanli ZHAO Chunqi LI Na WANG Chunyan 《Journal of Ocean University of China》 SCIE CAS 2013年第1期175-182,共8页
Two sulfated polysaccharides, designated MP and SP, were extracted from the marine green alga Enteromorpha linza using hot water and then purified using ion-exchange and size-exclusion chromatography. The anticoagulan... Two sulfated polysaccharides, designated MP and SP, were extracted from the marine green alga Enteromorpha linza using hot water and then purified using ion-exchange and size-exclusion chromatography. The anticoagulant activities of MP and SP were examined by determination of their activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) using human plasma. Results showed that MP and SP were composed of abundant rhamnose with small amounts of xylose and glucuronic acid, whereas SP also contained a small amount of galactose. Approximate molecular weights of MP and SP were 535 and 502 kDa, respectively. As compared with SP, MP had higher contents of sulfate ester (19.0%) and uronic acid (14.9%). The MP mainly consisted of (1→4)-linked rhamnose residues with partially sulfated groups at the C-3 position, and small amounts of (1→3, 4)-linked rhamnose, (1→2,4)-linked rhamnose, (1→4)-linked glucuronic acid and (1→4)-linked xylose residues. The SP contained abundant (1→4)-linked rhamnose with minor amounts of (1→3)-linked rhanmose, (1→3, 4)-linked rhamnose, (1→2, 4)-linked rhanmose, (1→4)4inked glucuronic acid, (1→4)-linked xylose, and (1→3)-linked galactose residues. The sulfate groups were mainly located at C-3 of (1→4)-linked rhamnose residues. Both MP and SP, in particular the former, effectively prolonged APTT and TT. This work demonstrates that MP and SP have unique structural characteristics distinct from those of other sulfated polysaccharides from Enteromorpha. The MP is a potential source of anticoagulant, and the difference in anticoagulant activities of the two sulfated polysaccharides is directly linked to the discrepancy of their chemical features. 展开更多
关键词 Marine green alga Enteromorpha linza sulfated polysaccharide chemical characteristic anticoagulant activity
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