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Study on the Quality Evaluation of Steamed Bread and the Physical and Chemical Properties of Wheat
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作者 Fenglan ZHANG Chengmei WANG De LI 《Agricultural Biotechnology》 CAS 2021年第2期125-127,共3页
In this study,the different physical and chemical properties of wheat were studied,and on this basis,and the quality of steamed bread made was evaluated.We analyzed the correlation between the evaluation indexes of st... In this study,the different physical and chemical properties of wheat were studied,and on this basis,and the quality of steamed bread made was evaluated.We analyzed the correlation between the evaluation indexes of steamed bread and the basic physical and chemical indexes of wheat,and investigated important factors that affect the evaluation indexes of steamed bread,including flour extraction rate,protein content,amylose content,protein,added amount of yeast,fermentation time and other aspects.According to the study results,it was shown that different factors had different effect on steamed bread quality,with both positive correlation and negative correlation. 展开更多
关键词 Steamed bread quality evaluation Wheat physical and chemical properties Correlation analysis
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The Effect of Some Soil Physical and Chemical Properties on Soil Aggregate Stability in Different Locations in Sulaimani and Halabja Governorate
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作者 Salahaddin Abdulqadir Aziz Saman Mahmood Karim 《Open Journal of Soil Science》 2016年第4期81-88,共8页
Some soil properties were studied in relation soil aggregate along a climatologically region and different crop land use in the Northeast of Sulaimani City/Kurdistan Region of Iraq. Five locations were selected along ... Some soil properties were studied in relation soil aggregate along a climatologically region and different crop land use in the Northeast of Sulaimani City/Kurdistan Region of Iraq. Five locations were selected along these regions ranging from semiarid to sub-humid climatologically conditions. The soil physical, chemical properties, aggregate stability and size distribution were analyzed. A mean-weight-diameter (MWD) value was determined on 5 soils, which was the sum of the percentage of soil on each sieve (6, 3, 1.5, 0.75, 0.375 and 0.125 mm). The results of the measurements could evaluated with linear correlation coefficients for the relationships between aggregate stability (MWD) and soil physical and chemical properties of the different crop land use. The correlation coefficient for the relationship between aggregate stability and organic matter was highly significant (P < 0.0l%) which is in agreement with the findings of [1]. Generally large aggregates (large 6, 3, 3 - 1.5 mm) were present in highest proportions in the most semiarid of the studied areas. Aggregates 0.75 - 0.125 mm were positively correlated to fine, very fine sand and silt fractions and to organic matter. Stability of aggregates showed a positive correlation with clay content and organic matter content, while the carbonate content was strongly correlated with aggregate stability. The land use history affecting soil overlaps the pattern of climatological situations and cultivated crop lands and has to be taken into account. Aggregate size distribution and stability can be used as indicator of soil conservation and productivity. 展开更多
关键词 Aggregate Stability Organic Matter Some physical and chemical properties Soil Consistency Limits
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Robinia pseudoacacia leaves improve soil physical and chemical properties 被引量:1
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作者 Babar KHAN Abdukadir Ablimit +1 位作者 Rashed MAHMOOD Muhammad QASIM 《Journal of Arid Land》 SCIE 2010年第4期266-271,共6页
The role of the leaves of Robinia pseudoacacia L., which is widely distributed in the arid lands, on improving soil physical and chemical properties was analyzed at various incubation periods. The incubated soils adde... The role of the leaves of Robinia pseudoacacia L., which is widely distributed in the arid lands, on improving soil physical and chemical properties was analyzed at various incubation periods. The incubated soils added with 0, 25, 50 and 75 g Robinia pseudoacacia leaves were tested after consecutive incubation intervals of 6, 8 and 10 months and the different soil parameters were measured. The results showed the increases in organic matter (OM), extractable K, cation exchange capacity (CEC), aggregate stability and water holding capacity, but the decreases in pH value and bulk density after 6 months' incubation. The gradual decrease in change rates of soil properties indicated less microbial population and organic residual mineralization under acidic conditions, which were resulted from fast decomposition of leaves after the first 6 months incubation. The increases in soil organic matter content, extractable K, CEC, aggregate stability and water holding capacity and the decreases in soil pH and bulk density provide favorable conditions for crop's growth. 展开更多
关键词 SOIL physical and chemical properties Robinia PSEUDOACACIA Gilgit-Baltistan
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Effects of Crude Oil Contamination on Soil Physical and Chemical Properties in Momoge Wetland of China 被引量:12
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作者 WANG Ying FENG Jiang +3 位作者 LIN Qianxin LYU Xianguo WANG Xiaoyu WANG Guoping 《Chinese Geographical Science》 SCIE CSCD 2013年第6期708-715,共8页
Large oilfields are often coincidentally located in major river deltas and wetlands,and potentially damage the structure,function and ecosystem service values of wetlands during oil exploration.In the present study,th... Large oilfields are often coincidentally located in major river deltas and wetlands,and potentially damage the structure,function and ecosystem service values of wetlands during oil exploration.In the present study,the effects of crude oil contamination during oil exploration on soil physical and chemical properties were investigated in marshes of the Momoge National Nature Reserve in Jilin Province,China.The concentrations of total petroleum hydrocarbons in the marsh soil near the oil wells are significantly higher than those in the adjacent control marsh.Soil water contents in oil-contaminated marshes are negatively correlated with soil temperature and are significantly lower than those in the control area,especially in fall.Crude oil contamination significantly increases the soil pH up to8.0,and reduces available phosphorus concentrations in the soil.The concentrations of total organic carbon are significantly different among sampling sites.Therefore,crude oil contamination could potentially alkalinize marsh soils,adversely affect soil fertility and physical properties,and cause deterioration of the marshes in the Momoge National Nature Reserve.Phyto-remediation by planting Calamagrostis angustifolia has the potential to simultaneously restore and remediate the petroleum hydrocarbon-contaminated wetlands.Crude oil contamination affects the soil physical and chemical properties,so developing an effective restoration program in the Momoge wetland is neccesary. 展开更多
关键词 土壤理化性质 莫莫格湿地 原油污染 中国 国家级自然保护区 生态系统服务价值 石油勘探 土壤水分含量
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Analysis of the Engineering Restoration Effect of Abandoned Yongledian Quarry in Beijing City Based on Soil Physical and Chemical Properties 被引量:2
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作者 Liwei CAI 《Asian Agricultural Research》 2014年第4期89-93,共5页
The improvement of the soil physical and chemical properties is the most important foundation for mine ecological restoration.The experiment is aimed at undisturbed area,restored area,and damaged area of abandoned Yon... The improvement of the soil physical and chemical properties is the most important foundation for mine ecological restoration.The experiment is aimed at undisturbed area,restored area,and damaged area of abandoned Yongledian Quarry in Beijing.Through determination and analysis of soil physical and chemical properties,it shows that there are significant differences in the composite effects of soil physical and chemical properties between restored area,and undisturbed area,damaged area,and engineering restoration effectively improves the composite effects of soil physical and chemical properties in the restored area.The single factor hypothesis test shows that soil pH value,organic matter,alkali-hydrolyzable nitrogen,and total nitrogen traits are the key targets to be restored in this mining area. 展开更多
关键词 Abandoned MINING area Yongledian QUARRY SOIL physi
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Soil Physical and Chemical Properties of Pure Pinus massoniana and Its Mixed Forests in Different Ages in Southern Guangxi 被引量:1
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作者 Zhongming HAO Shuirong WU +2 位作者 Lin QIN Ling TAN Wenfu GUO 《Asian Agricultural Research》 2018年第8期53-57,共5页
Six forest stands of 59,34 and 24 year-old Pinus massoniana forests and their mixed forests were selected at the Experimental Center of Tropical Forestry of Chinese Academy of Forestry,and 20 m × 20 m plot was se... Six forest stands of 59,34 and 24 year-old Pinus massoniana forests and their mixed forests were selected at the Experimental Center of Tropical Forestry of Chinese Academy of Forestry,and 20 m × 20 m plot was set up and soil samples were taken from 0-60 cm soil layers,to analyze the changes of soil nutrient content under different forest stands and forest ages. The results showed that soil moisture and the bulk density in the mesophytic forest land were higher than those of other forest lands. The highest soil porosity value was observed in the early forest land. Soil p H of different forest was 4. 45-4. 75,indicating the variation was small. Besides,it indicated that the mixed forest was more able to increase the soil fertility than the pure forest because that the variation of soil acidity,organic matter content and total P and K in 34 and24 year-old mixed forests were higher than those in pure forests of the same year old. However,the content of soil available P and K decreased with the increase of soil depth,and varied in terms of forest ages. From the changes of soil indicators in different forest lands,soil nutrients in the 34 year-old P. massoniana forest was superior to that of other forest stands. 展开更多
关键词 林业科学 中国 热带林业 理论研究
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Effect of Different Cultivation Practices on Soil Physical and Chemical Properties for Greenhouse Vegetables under Long-Term Continuous Cropping 被引量:2
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作者 Lijuan GAO Guoyuan ZOU +3 位作者 Lianfeng DU Shunjiang LI Jing LIU Hongkai DUAN 《Asian Agricultural Research》 2018年第9期74-81,共8页
Five kinds of greenhouse vegetables( eggplant,loofah,tomato,cucumber and pepper) were selected in summer uprooting stage from greenhouse in Shouguang area,Shandong Province. Total nitrogen,ammonium nitrogen,nitrate ni... Five kinds of greenhouse vegetables( eggplant,loofah,tomato,cucumber and pepper) were selected in summer uprooting stage from greenhouse in Shouguang area,Shandong Province. Total nitrogen,ammonium nitrogen,nitrate nitrogen,available phosphorus,available potassium,organic matter content and p H,EC value of three soil layers were measured,respectively. The results showed that the total nitrogen,ammonium nitrogen,nitrate nitrogen,available phosphorus and available potassium in the soil were mainly accumulated in the upper soil,which made the soil acidification trend,because different farmers adopted different cultivation practices for different greenhouse vegetables in Shouguang region,but there was no significant effect on soil EC value. The input of ammonium nitrogen and nitrate nitrogen and other related fertilizers to greenhouse cucumber was higher than that of other greenhouse vegetables,but the amount of available potassium fertilizer and organic matter input to greenhouse tomato under different cultivation practices was lower than other greenhouse vegetables. In Shouguang area,the input of organic matter into greenhouse vegetables should be increased by increasing the proportion of manure input to increase the content of soil organic carbon,so as to achieve the balance of carbon and nitrogen ratio,and to provide a scientific basis for the establishment of an evaluation system for the environmental benefits brought about by chemical fertilizer reduction in greenhouse vegetables in Shouguang area. 展开更多
关键词 茄子 有机肥 肥料 种植业
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Effect of Spent Mushroom Substrate on Physical and Chemical Properties and Enzymic Activity of Rice
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作者 Hairu YU Xue LI +5 位作者 Xin ZHANG Changming GE Renzhe PIAO Meishan LI Zongjun CUI Hongyan ZHAO 《Asian Agricultural Research》 2016年第6期65-67,72,共4页
In order to explore the substitution substrate for rice seedling on upland fields,this paper uses spent mushroom substrate to study the physical and chemical properties of substrate,enzymic activity and number of till... In order to explore the substitution substrate for rice seedling on upland fields,this paper uses spent mushroom substrate to study the physical and chemical properties of substrate,enzymic activity and number of tillers during the cultivation of rice seedling on upland fields.The results show that at the three stages of rice seedling cultivation( two-leaf stage,three-leaf stage,four-leaf stage),the content of organic matter and EC in spent mushroom substrate is higher than in the control soil,p H is within the range suitable for the growth of rice,and other nutrients( total nitrogen,total phosphorus,total potassium,available nitrogen,available phosphorus) are slightly different in different periods;except phosphatase,there are significant differences in urease,catalase and sucrase between spent mushroom substrate and the control soil; the number of tillers under spent mushroom substrate is larger than under the control. 展开更多
关键词 SPENT MUSHROOM SUBSTRATE RICE physical and chemical INDICATORS Enzymic activity
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Banded Iron Formations (BIFs) and Associated Sediments Do Not Reflect the Physical and Chemical Properties of Early Precambrian Seas
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作者 Zeev Lewy 《International Journal of Geosciences》 2012年第1期226-236,共11页
Ring-in-ring structures in Australian Early Precambrian banded iron formation (BIF) were identified as bubbling mud wavelets, which lithified during temporary exposure, contradicting the alleged BIF deep ocean origin.... Ring-in-ring structures in Australian Early Precambrian banded iron formation (BIF) were identified as bubbling mud wavelets, which lithified during temporary exposure, contradicting the alleged BIF deep ocean origin. Least altered BIFs consist of alternating chert laminae with, and without iron oxides (or carbonates). They were precipitated during on-and-off periods of ferrous iron oxidation controlled by microbial oxygenic photosynthetic activity during solar illumination, which stopped during darkness as characterizing the Polar Regions, thus forming genuine annual varves. This polar environment is further corroborated by the magnetite-hematite-magnetite microcrystal layers in the iron-rich laminae reflecting mid-spring-summer-autumn changes in solar radiation, and by diamictite at the end of the sequence deposited from melting glaciers when the continental plate shifted to lower latitudes. BIF sequences in various countries comprise evaporates. They attest to intensive evaporation of the warm hydrothermal solution in restricted shallow lakes under the freezing dry climate up to silica (geyserite) precipitation referred to chert. The existence of oceans, mid-ocean-ridges and island arcs during the Early Precambrian results from the misinterpreted oceanic origin of BIFs and the Phanerozoic occurrences of the associated mafic-ultramafic basalt flows (Greenstone Belt). 展开更多
关键词 Early PRECAMBRIAN BIF NON-MARINE POLAR Regions physical and chemical Control
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Effects of Long-term Site-specific Fertilization on Soil Physical and Chemical Properties and Nutrients in Dry Farmland
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作者 Xiaojun WANG Yuqing SUN +6 位作者 Yong WANG Xiaojuan ZHANG Shangpei ZHANG Junxue YANG Shiwu LUO Jihong SHANG Bingwen CHENG 《Agricultural Science & Technology》 CAS 2017年第11期2118-2122,共5页
In order to investigate the variation in soil physical and chemical properties and nutrients in the mountainous areas in southern Ningxia, and to provide a theoretical basis for fertilization management in local farml... In order to investigate the variation in soil physical and chemical properties and nutrients in the mountainous areas in southern Ningxia, and to provide a theoretical basis for fertilization management in local farmland, the soil p H, total salt content,crop root length, root weight, soil organic matter, available nitrogen, total nitrogen, total phosphorous and total potassium in different fertilization treatments were measured from 2010 to 2016. Multiple comparisons of the data were performed using Duncan's new multiple range test. The results indicated that in the 0-20 cm soil layer, soil p H value and total salt content changed in different patterns, and varied greatly from 2010 to 2016(P<0.05). The changes of both root length and root weight of millet over time fitted S-shaped curves. The root length and root weight in the four fertilization treatments(Treatment 2 to Treatment5) increased faster than those in the control(Treatment 1). The soil organic matter content in all the five treatments gradually increased from 2010 to 2016. The content of alkaline hydrolyzable nitrogen in soil rapidly increased in the first two to three years of the experiment, followed by a slow increase or decrease in 2013, and then raised rapidly again from 2014 to 2016.The soil total nitrogen content varied significantly from 2010 to 2016. The total phosphorus content in soil changed in a different pattern from that of total nitrogen content. The seven-year field trails revealed that soil p H, total salt content, root length, root weight and soil nutrient all changed with the increase of fertilizer level, and that long-term fertilization is of significance for maintaining soil fertility, improving soil quality and reducing soil salinization. 展开更多
关键词 土壤理化性质 旱作农田 土壤养分 长期定位施肥 土壤有机质含量 宁夏南部山区 全氮含量 总磷含量
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Selected physical and chemical properties of mechanically extracted neem seed oil sourced as a preservative for ligno-cellulose in south-western Nigeria
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作者 Andrew A. ERAKHRUMEN 《Forestry Studies in China》 CAS 2011年第4期263-269,共7页
Most of the seeds produced by neem (Azadirachta indica A. Juss) trees in Nigeria are currently underutilized. Hence, relevant literature provides only limited information concerning many of the seed oils from this cou... Most of the seeds produced by neem (Azadirachta indica A. Juss) trees in Nigeria are currently underutilized. Hence, relevant literature provides only limited information concerning many of the seed oils from this country, especially where it concerns the potential applications of these oils as preservatives for ligno-cellulose against bio-deterioration. Using standard procedures therefore, this study was carried out to evaluate and document selected physical and chemical properties of neem seed oil (NSO), mechanically extracted using a cold press at 31.03 N·mm -2 pressure and a room temperature of 25 ± 2℃. The results show that oil yield was 38.42% with a specific gravity of 0.91 ± 0.01. The amount of acid was 18.24 ± 1.31 mg KOH·g -1 and that of iodine 93.12 ± 2.01 g·100 g -1 , while saponification and peroxide values were 172.88 ± 2.06 and 1.42 ± 0.04 mg·g -1 respectively. The implication of the values obtained, particularly those for the chemical properties, as they concern the potential application of NSO as a preservative for ligno-cellulose, is likely that it may be useful in this regard since the values may support some of the documented anti-microbial properties of the oil, although other physical and chemical properties that may affect this potential are recommended for investigations. Conclusions and other recommendations follow in line with the results of the study. 展开更多
关键词 木质纤维素 化学性质 尼日利亚 防腐剂 物理 印楝 提取 机械
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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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GIS-Based Assessment of Soil Chemical and Physical Properties as a Basis for Land Reclamation in Toshka Area, Aswan, EGYPT
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作者 Ahmed A. M. Awad Mostafa M. A. Al-Soghir 《Open Journal of Geology》 2023年第7期697-719,共23页
The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the... The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the chemical and fertility index for assisting land reclamation in Toshka area. The Toshka area is located between latitudes 31°32'N and 31°36'N and longitudes 32°40'E and 32°60'E. GIS was used to select 16 sites. The results revealed the soil has undesirable characteristics. The soil pH ranged from slightly alkaline to moderately alkaline. Furthermore, it was characterized as saline (with a ECe of 4.65 - 11.45 dS⋅m<sup>−1</sup>) and moderately calcareous soil (with CaCO<sub>3</sub> at 11.85% - 17.20%). The soil had a low soil organic matter content which did not exceed 0.18%. The soil was dominated by a sandy loam texture (62.50%) followed by a sandy clay loam texture (18.75%). The bulk density, total soil porosity and saturated hydraulic conductivity values varied with 1.38 - 1.55 Mg⋅cm<sup>−3</sup>, 41.85% - 48.45% and 1.20 - 3.34 cm⋅h<sup>−1</sup>, respectively. The chemical index ranged from low to moderate quality. The correlations between the parameters osculated between negative and positive. Therefore, the soil may be reclaimed if the soil properties are improved and crop selection is optimized for this soil. 展开更多
关键词 Land Reclamation Soil chemical and physical properties chemical Quality Index Fertility Quality Index
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Classification and comparison of physical and chemical properties of corn stalk from three regions in China 被引量:5
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作者 Wang Lu Liu Ronghou +4 位作者 Sun Chen Cai Wenfei Tao Yiwei Yin Renzhan Mei Yuanfei 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2014年第6期98-106,共9页
Corn stalk samples from Anhui,Jiangxi and Shanghai were used as test materials.Their physical,chemical and thermo-chemical engineering characteristics were analyzed.The similarities and differences in properties of co... Corn stalk samples from Anhui,Jiangxi and Shanghai were used as test materials.Their physical,chemical and thermo-chemical engineering characteristics were analyzed.The similarities and differences in properties of corn stalk from the three regions were determined using SIMCA-P and SPSS software in order to obtain a proper energy utilization method of corn stalk.The results show that the corn stalk from Shanghai has significant differences from the samples of Jiangxi and Anhui.In particular,the following properties of corn stalk from Shanghai such as the contents of cellulose,calcium(Ca),iron(Fe),crude ash,volatile matter,carbon(C),nitrogen(N),and oxygen(O)are significantly different from those of Jiangxi and Anhui samples(P<0.05).While other properties such as the contents of magnesium(Mg),copper(Cu),zinc(Zn),moisture,hydrogen(H),and sulfur(S)have no significant difference among samples of three regions.Compared with the corn stalk in Anhui and Jiangxi,the Shanghai samples are more suitable for the production of ethanol because of their higher ratio of cellulose to hemi-cellulose content.Because of its high content of ash and low calorific value,the Shanghai corn stalk is suitable for the gasification process instead of for direct combustion or bio-oil production.The research can provide a reference for raw material selection for biomass energy production and utilization. 展开更多
关键词 corn stalk physical and chemical properties BIOENERGY principal components analysis partial least squares discriminant analysis
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Research and Discussion on Physical and Chemical Properties of Cultivating Substrate with Facilities 被引量:1
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作者 MA Ying1 YIN Shulian1 ZHANG Yongxin2 1. Department of Garden in Hebei Professional College of Political Science and Law, Shijiazhuang 050061, P. R . China 2. Flower management centre in Hebei Province Forestry Bureau, Shijiazhuang 050061, P. R. China 《Chinese Forestry Science and Technology》 2008年第2期49-55,共7页
This article, by comparing the basic concepts of substrate and soil, their composition of substance and methods of measuring the indexes of physical and chemical properties, analyzes and researches ways of choosing su... This article, by comparing the basic concepts of substrate and soil, their composition of substance and methods of measuring the indexes of physical and chemical properties, analyzes and researches ways of choosing substrate for cultivation with facilities. It indicates that the normal physical and chemical indexes of evaluating a substrate are bulk density, total porosity, non-capillary porosity, ratio of big porosity to small porosity, the pH and the electrical conductivity (EC) value of the substrate. By measuring the physical and chemical properties of the substrate in different prescription and the cultivation experiments, the best substrate can be sieved. 展开更多
关键词 cultivating with facilities SUBSTRATE SIEVE physical and chemical properties APPLICATION
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Establishment and verification of prediction models for evaluating the physical and chemical properties of soilless substrates
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作者 Binbin Gong Ning Wang +6 位作者 Tiejun Zhang Shao Li Xiaolei Wu Jing Tian Jingrui Li Guiyun Lyu Hongbo Gao 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2021年第2期9-18,共10页
In soilless culture,a suitable mixed substrate that provides a balanced and stable rhizosphere environment is vital for promoting plant growth.The present study was undertaken to establish seven prediction models of p... In soilless culture,a suitable mixed substrate that provides a balanced and stable rhizosphere environment is vital for promoting plant growth.The present study was undertaken to establish seven prediction models of physical and chemical properties,including bulk density(DB),total porosity(TP),water-holding porosity(WHP),air porosity(AP),WHP/AP,electrical conductivity(EC)and cation exchange capacity(CEC)of mixed substrate based on regression equations of measured values from 76 substrate combinations.These seven models were verified using the measured values of 12 mixed substrates,and the average relative prediction errors(REs)were all less than 10%.A comprehensive property prediction model was established by weighted summation of the seven models of physical and chemical properties.According to the set values of DB,TP,WHP,AP,WHP/AP,EC and CEC,the comprehensive property model predicted the six mixture proportions of mixed-substrate,as verified using the measured values.This study is the first to establish prediction models for the physical and chemical properties of mixed substrates.The comprehensive property model could be used to evaluate the physical and chemical properties of commercial mixed substrates,and to provide the optimal mixture substrate formulations according to the setting property value of production requirement. 展开更多
关键词 prediction model mixed substrate physical and chemical properties multiple regressions genetic algorithm
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Impacts of solid physical properties on the performances of a slurry external airlift loop reactor integrating mixing and separation
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作者 Tian Zhang Qingshan Huang +3 位作者 Shujun Geng Aqiang Chen Yan Liu Haidong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期1-12,共12页
Solid physical properties are vital for the design, optimization, and scale-up of gas–liquid–solid multiphase reactors. The complex and interactional effects of the solid physical properties, including particle diam... Solid physical properties are vital for the design, optimization, and scale-up of gas–liquid–solid multiphase reactors. The complex and interactional effects of the solid physical properties, including particle diameter, density, wettability, and sphericity, on the hydrodynamic behaviors in a new external airlift loop reactor(EALR) integrating mixing and separation are decoupled in this work. Two semi-empirical equations are proposed and validated to predict the overall gas holdup and liquid circulating velocity satisfactorily, and then the individual influence of such solid physical properties is further investigated. The results demonstrate that both the overall gas holdup in the riser and the liquid circulating velocity in the downcomer increase with the contact angle, but decrease with particle size, density, and sphericity.Additionally, the impact of the particle size on the liquid circulating velocity is also profoundly revealed on a micro-level considering the particle size distribution. Moreover, the axial solid concentration distribution is discussed, and the uniformity of the slurry is described by the mixing index of the solid particles. The results show that a more homogeneous mixture can be achieved by adding finer particles other than attaining violent turbulence. Therefore, this work lays a foundation for the design, scale-up, and industrialization of the EALRs. 展开更多
关键词 Slurry reactor HYDRODYNAMICS Particle MIXING Solid physical property
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Digital mapping of soil physical and mechanical properties using machine learning at the watershed scale
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作者 Mohammad Sajjad GHAVAMI Shamsollah AYOUBI +1 位作者 Mohammad Reza MOSADDEGHI Salman Naimi 《Journal of Mountain Science》 SCIE CSCD 2023年第10期2975-2992,共18页
Knowledge about the spatial distribution of the soil physical and mechanical properties is crucial for soil management,water yield,and sustainability at the watershed scale;however,the lack of soil data hinders the ap... Knowledge about the spatial distribution of the soil physical and mechanical properties is crucial for soil management,water yield,and sustainability at the watershed scale;however,the lack of soil data hinders the application of this tool,thus urging the need to estimate soil properties and consequently,to perform the spatial distribution.This research attempted to examine the proficiency of three machine learning methods(RF:Random Forest;Cubist:Regression Tree;and SVM:Support Vector Machine)to predict soil physical and mechanical properties,saturated hydraulic conductivity(Ks),Cohesion measured by fall-cone at the saturated(Psat)and dry(Pdry)states,hardness index(HI)and dry shear strength(SS)by integrating environmental variables and soil features in the Zayandeh-Rood dam watershed,central Iran.To determine the best combination of input variables,three scenarios were examined as follows:scenarioⅠ,terrain attributes derivative from a digital elevation model(DEM)+remotely sensed data;scenarioⅡ,covariates of scenarioⅠ+selected climatic data and some thematic maps;scenarioⅢ,covariates in scenarioⅡ+intrinsic soil properties(Clay,Silt,Sand,bulk density(BD),soil organic matter(SOM),calcium carbonate equivalent(CCE),mean weight diameter(MWD)and geometric weight diameter(GWD)).The results showed that for Ks,Psat Pdry and SS,the best performance was found by the RF model in the third scenario,with R2=0.53,0.32,0.31 and 0.41,respectively,while for soil hardness index(HI),Cubist model in the third scenario with R2=0.25 showed the highest performance.For predicting Ks and Psat,soil characteristics(i.e.clay and soil SOM and BD),and land use were the most important variables.For predicting Pdry,HI,and SS,some topographical characteristics(Valley depth,catchment area,mltiresolution of ridge top flatness index),and some soil characteristics(i.e.clay,SOM and MWD)were the most important input variables.The results of this research present moderate accuracy,however,the methodology employed provides quick and costeffective information serving as the scientific basis for decision-making goals. 展开更多
关键词 Machine learning Soil physical property Soilmechanical property Saturatedhydraulic conductivity Soil cohesion Soil shear strength.
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Physical and emulsifying properties of pea protein:influence of combined physical modification by flaxseed gum and ultrasonic treatment
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作者 Jia Yang Fenghong Huang +6 位作者 Qingde Huang Da Ma Yashu Chen Dengfeng Peng Xiao Yu Qianchun Deng Fang Geng 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期431-441,共11页
This study characterized and compared the physical and emulsifying properties of pea protein(PP)and its modified proteins(ultrasound treated-PP(PPU),flaxseed gum(FG)treated PP(PPFG)and ultrasound treated-PPFG(PPFGU)).... This study characterized and compared the physical and emulsifying properties of pea protein(PP)and its modified proteins(ultrasound treated-PP(PPU),flaxseed gum(FG)treated PP(PPFG)and ultrasound treated-PPFG(PPFGU)).The results showed FG triggered the formation of loosely attached complex with PP via physical modification under gentle magnetic stirring at pH 7.0,while ultrasound played an important role in reducing protein size,increasing surface hydrophobicity and molecular fluidity onto oil-water interface.So ultrasound further enhanced the interaction of PP with FG,and produced the PPFGU complex with smaller droplet size,higherζ-potential and lower turbidity.Further,combination of FG and ultrasound improved the physical properties of PP with higher viscosity,stiffer gels(defined as higher elastic modulus),stronger hydrophobic properties,better thermal stability,and fast protein absorption rate.Therefore,the PPFGU coarse emulsion performed highest emulsifying activity index(EAI)and emulsion stability index(ESI)that the stabilized nanoemulsion obtained smallest droplet size,higherζ-potential,and longest storage stability.The combination of FG and ultrasonic treatment will be an effective approach to improving the emulsifying property and thermal stability of PP,which can be considered as a potential plant-based emulsifier applied in the food industry. 展开更多
关键词 Pea protein Flaxseed gum Ultrasonic treatment Emulsifying properties physical properties
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Differences of tuffaceous components dissolution and their impact on physical properties in sandstone reservoirs: A case study on Paleogene Wenchang Formation in Huizhou-Lufeng area, Zhu I Depression, Pearl River Mouth Basin, China
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作者 JIN Zihao YUAN Guanghui +4 位作者 ZHANG Xiangtao CAO Yingchang DING Lin LI Xiaoyan FU Xiaohan 《Petroleum Exploration and Development》 2023年第1期111-124,共14页
The element geochemical characteristics and diagenetic alteration products of tuffaceous components in sandstone reservoirs of Paleogene Wenchang Formation in typical subsags of the Huizhou-Lufeng area of the Zhu I De... The element geochemical characteristics and diagenetic alteration products of tuffaceous components in sandstone reservoirs of Paleogene Wenchang Formation in typical subsags of the Huizhou-Lufeng area of the Zhu I Depression,Pearl River Mouth Basin,were identified through microscopic analysis and quantitative analysis of main and trace elements.The impacts of dissolution of different tuffaceous components on physical properties of reservoirs were discussed through quantitative characterization of reservoir physical properties.The results show that there are mainly four types of tuffaceous components in the study area,which are acidic,intermediate,basic and alkaline tuffaceous components.The acidic tuffaceous components evolved in a process of strong alteration and weak dissolution of alteration products,with a large amount of kaolinite precipitated during alteration to disenable the improvement of porosity and permeability.The intermediate and alkaline tuffaceous components evolved in a process of strong dissolution of tuffaceous components and strong alteration of residual tuffaceous components;the dissolution of tuffaceous components created intergranular pores,but the alteration products such as autogenic quartz,apatite and illite deteriorated the pore structure;ultimately,the dissolution of tuffaceous components resulted in the increase of porosity but no increase of permeability of the reservoir.The basic tuffaceous components dominantly evolved in a process of dissolution of tuffaceous components to strong dissolution of alteration products;both tuffaceous components between particles and laumontite generated from alteration can be strongly dissolved to create pores;thus,the dissolution of tuffaceous components can significantly increase the physical properties of the reservoir. 展开更多
关键词 Zhu I Depression Huizhou Sag Lufeng Sag tuffaceous component DISSOLUTION physical property response Paleogene Wenchang Formation
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