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Journal of Environmental Science and Engineering(B) 2014年第6期3卷 300-303页

作者： Oleg Romanov Department of Soil Science and Soil Ecology St. Petersburg State University St. Petersburg 199178 Russia

Soils developed from the Quaternary loesslike loams have been studied in the south of the forest-steppe zone on the Central Russian Upland. A polygenetic nature of the soil profile on the loesslike loams is shown. The modem pedogenetic processes in this soil ensure its eluvial-illuvial differentiation with the development of multilayered coatings in the illuvial horizon. The middle horizons in the studied soil profiles are referred to as textural （clay-illuvial） horizons. Differences in physical soil properties （bulk density, airconductivity, texture, water content, and temperature dynamics） were studied in the soil on the loesslike loam.

关键词： Physical soil properties bulk density texture water content loesslike loam.

Relationship Between pH Value and Physical and Chemical Properties of Tobacco-growing Soil

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Agricultural Biotechnology 2021年第2期10卷 99-101,106页

作者： Yunfei CHEN Jiye QIANG Ailian OUYANG Colleege of Agruicultural and Forestry Pu'er UniversityPu'er 665000China Rural Development Research Center Pu'er UniversityPu'er 665000China

[Objectives]This study was conducted to understand the relationship between soil pH and soil physical and chemical properties during tobacco planting.[Methods]Through a field experiment,the pH value of tobacco-growing soil,the contents of mineral nutrients(ammonium nitrogen,alkali-hydrolyzable nitrogen,available potassium,available phosphorus),soil bulk density and porosity were investigated.[Results]The pH value of the soil after tobacco planting increased,and the contents of ammonium nitrogen,alkali-hydrolyzable nitrogen,and available potassium were closely related to the change of pH *** bulk density of the tobacco-planting soil decreased and the porosity *** flue-cured tobacco had certain impacts on soil pH,soil bulk density and other physical and chemical properties.[Conclusions]This study provides a theoretical basis for the investigation of the fertilization laws in the process of tobacco planting and the selection of subsequent crops.

关键词： Tobacco growing soil pH value Mineral nutrients bulk density Porosity

Study on the Influences of Foaming Gypsum’s Performance

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Study on the Influences of Foaming Gypsum’s Performance

The Evolution of Soil Structural Repair under Zero Till, Controlled Traffic, Permanent Bed Farming

中国材料大会2012

作者： Bin Huang Yi Zhang Dongxu Li College of Materials Science ＆ Engineering Nanjing University of Technology

ISBN: (纸本)9783037856062;3037856068

Utilizing the chemical reaction principles H2O2 was catalyzed by MnO2 , instead of being catalyzed by warm water. In the gypsum slurry, due to the chemical reaction of hydrogen peroxide a large number of bubbles were produced, and the material was self-foaming. The H2O2 foaming agent and the method of foaming affected the performance of the foaming gypsum, such as mechanical strength, apparent density, thermal conductivity, and the pore structure of foaming gypsum. The result showed that with adding H2O2 , the apparent density and mechanical strength decreased;the different water/plaster weight ratio ranged from 0.65 to 0.75, affecting the foaming process. The thermal insulation property of FGD gypsum is related to the content of H2O2 , the water/plaster weight ratio, and the pore structure of foaming gypsum.

关键词： Foaming agent bulk density Porosity Pore structure Thermal conductivity.

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The Evolution of Soil Structural Repair under Zero Till, Con...

Selecting Subsoilers to Reduce Soil Compaction and Minimize Residue Burial

国际农业工程大会

作者： A. D. McHugh J. N. Tullberg（Presenting Author） D. M. Freebairn Queensland Department of Natural Resources Mines ＆ Energy PO Box 19 Emerald Qld 4720 Australia Agronomy and Horticulture University of Queensland Gatton Qld 4343 Australia Queensland Department of Natural Resources Mines ＆ Energy PO Box 318 Toowoomba Qld 5350 Australia

＜正＞ Soil structural degradation is widespread in cropping lands and efforts to restore deteriorated soil structure very often fail, largely as a result of the tillage and traffic effects. Significant reductions in biological activity in the soil environment occur where random traffic is practiced, limiting the regenerative capacity of vertosols. This study assessed the changes in soil structure after random field wheeling was replaced with zero till permanent bed controlled traffic farming （CTF） through four cropping seasons. The rate and depth of soil amelioration by natural processes was assessed by changes in, soil water retention characteristics, macro porosity and bulk density.

关键词： Vertosols Amelioration bulk density Available water capacity Compaction Controlled traffic permanent beds zero tillage Macropore density

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Selecting Subsoilers to Reduce Soil Compaction and Minimize ...

Degree of compaction and compression strength of Nigerian Alfisol under tilled condition and different machinery traffic passes

国际农业工程大会

作者： R.L. Raper Agricultural Engineer Lead Scientist USDA-ARS-National Soil Dynamics Laboratory Conservation Systems Research 411 S. Donahue Drive Auburn AL 36832

＜正＞ Aboveground soil disruption prior to planting is avoided in conservation tillage systems due to the need to keep plant residue in place. However, belowground disruption is necessary in many Southeastern U.S. soils to ameliorate soil compaction problems. For use in conservation tillage systems, belowground soil disruption should be maximized while aboveground disruption should be minimized. To assist in choosing the best shank for strip-tillage systems which accomplish both objectives, comparisons were made between several shanks commonly used for conservation tillage systems to provide in-row subsoiling prior to planting.

关键词： Draft force drawbar power cone index bulk density residue bentleg shanks subsoiler soil compaction

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International Journal of Agricultural and Biological Engineering 2012年第2期5卷 34-41页

作者： Fasinmirin Johnson Toyin Adesigbin Adedayo Joseph Department of Agricultural Engineering Federal University of TechnologyAkureNigeria

Information on the effect of soil compaction on soil mechanical properties such as degree of compaction,compression and shear strength of tropical soils of Nigeria under different machinery traffic passes is very *** experiment was conducted in a tilled and compacted sandy clay loam(Alfisol)in Akure,Nigeria,under different machinery traffic passes to determine compaction effects on bulk density,compression strength,degree of compaction and the shear strength of *** plots,A,B,C and D of area 20 m×50 m each were used for the field *** plot A was tilled with a tractor-mounted disc plough,and the remaining three plots:B,C and D were subjected to 5,10 and 15 to and fro passes,respectively,using heavy duty Mercy Fergusson tractor model 4355(3.82 Mg).The treatments were replicated three times in a randomized complete block *** plots progressively increased the bulk density from 1.63 g/cm^(3) to 1.90 g/cm^(3),but the highest bulk density was observed in plots under 15 traffic passes with the value of(1.90±0.23)g/*** percentage of soil compaction varies from 90.5%to 97%at the 0-10 cm soil *** compression strength of soil increased from 31.00 kPa to 42.05 kPa and from 29.68 to 65.44 kPa at the 0-10 cm and 10-20 cm soil layers,respectively,which resulted in the increased shear strength from 15.79 kPa to 21.03 kPa and 14.8 kPa to 32.72 kPa at the 0-10 cm and 10-20 cm in plots under 5 and 15 traffic passes,*** A(tilled soil)had the lowest bulk density,degree of compaction and compression strength with values(1.51±0.19)g/cm^(3),88.2%,and(12.15±0.37)kPa,respectively,and consequently the lowest shear strength of(6.02±1.23)kPa,which enhanced air movement and microbial activities in the *** under 15 traffic passes,especially at the 10-20 cm soil layer,may result in poor root penetration when cropped but can be very reliable and consistent when used for structural purposes.

关键词： soil compaction tillage degree of compaction compression strength shear strength farm machine traffic passes bulk density

Thermo-physical properties of rubber seed useful in the design of storage structure

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International Journal of Agricultural and Biological Engineering 2012年第2期5卷 62-66页

作者： A.Fadeyibi Z.D.Osunde Department of Agricultural and Bioresources Engineering Federal University of TechnologyMinnaNigeria

This study was carried out to determine the thermo-physical properties of rubber seed in the moisture range of 9.1%to 14.8%(w.b.).The length,width,thickness,measured surface area,bulk density and true density increased with increasing moisture content with high coefficients of determination(significant at p<0.05).Their optimum values at 14.8%moisture content were 17.00 mm,11.94 mm,8.26 mm,285.20 mm^(2),295.00 kg/m^(3) and 470.67 kg/m^(3),*** angle of repose increased as moisture content increased with low coefficient of determination and has optimum value of 28.81°at 14.8%moisture *** specific heat capacity and thermal conductivity decreased linearly while thermal diffusivity increased exponentially with an increase in moisture content(significant at p<0.05).The optimum values of specific heat capacity,thermal conductivity and diffusivity at 14.8%moisture content were 55.84 kJ/(kg.K),0.032 W/(m.K)and 1.93×10^(-9) m^(2)/s,*** results are essential in the design of storage structure for rubber seed.

关键词： thermo-physical properties rubber seed storage specific heat capacity bulk density storage structure design

Physicomechanical Properties of Rice Husk Pellets for Domestic Combustion in Myanmar

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Journal of Mechanics Engineering and Automation 2020年第2期10卷 66-72页

作者： Swe Zin Tun NweNwe Win Stefan Beisl Anton Friedl Department of Chemical Engineering Yangon Technological University Yangon 11011Myanmar 2.Department of Chemical EngineeringWest Yangon Technological UniversityYangon 11402Myanmar Institute of Chemical Environmental and Bioscience EngineeringTU WienGetreidemarkt 9/166A-1060Austria

Myanmar produces 26.21 million tons of rice annually that results in 5.24 million tons of remaining rice husk of which only around 30%is used for electricity and heat production in the *** needs more energy consumption to develop the agricultural economy and biomass energy in the future of the *** proximate and ultimate analysis of rice husk and produced rice husk pellets were determined as well as analyzing the physicochemical and mechanical *** rice husk pellets without doing size reduction were manufactured in a ring die pellet *** and pellet-formed rice husk were compared based on the ISO 17225-6 standard for the characterization of herbaceous *** increased the bulk density of rice husk by a factor of *** net calorific value of Myanmar rice husk pellets was 3.67 kW h/kg with a moisture content of 7.48%and the large amount of ash forming *** result showed that the diameter,length,and durability of the produced pellets complied with ISO 17225-6 ***,the net calorific value and bulk density could only be partially fulfilled according to the ISO standard depending on the process parameters.

关键词： Rice husk pellets bulk density calorific value durability

Physico-chemical Characteristics of the Soils in Three Church Forest of Central Ethiopia

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Research in Ecology 2020年第4期2卷 1-8页

作者： Eguale Tadesse Kifle Ethiopian Environment and Forest Research Institute Central Ethiopia Environment and Forest research CenterGurd SholaAddis AbabaEthiopia

positively or negatively depending on the *** has influence on the soil physico-chemical *** use land cover changes are the main factors in the process of land resource *** objectives of this study were to define the soil texture,bulk density and extent of organic carbon in church forests and adjacent croplands and to compare the *** lines of 100 meter apart and plots of 20 m×20 m were established to collect soil samples in the church forests and individual farm *** distance between plots was 100 *** based soil sampling was *** samples were collected on a diagonal position from 2 edges and the center from 2 soil horizons(H1 and H2)for soil texture and soil organic carbon(SOC)*** bulk density(BD)soil core samplers were *** data was analyzed using one way ANOVA in SPSS *** separation was undertaken by least significance *** results revealed the%clay content was significantly higher in croplands than church forests and the%sand was higher in church forests than croplands at(pbulk density.

关键词： bulk density Farm land Land use Organic carbon Vegetation Soil texture Soil horizons