Factors affecting the swelling pressure for Jerash expansive soil

In this study for factors effecting the swelling pressure of jerash expansive soils were investigated in this study, effect of initial dry density and effect of initial water content on the jerash expansive soil were investigated.It show that as the initial dry density decrease from 1.85 gm/cm3 to1.25 gm/cm3 , the swelling pressure also decrease are from 3.1 to 0.25gm/cm2 also it show that as the initial water content increase from 0%to 15% , the swelling pressure of jerash expansive soil decrease from 2.65 gm/cm2 to 1.35 gm/cm2 .

Optimization of hammer grinder for white lupine “Dega” processing

Исследования проведены в 2019 году в лаборатории «Технология и техника мукомольно-крупяного производства» ВНИИ зерна и продуктов его переработки – филиала ФГБНУ «ФНЦ пищевых систем им. В. М. Горбатова» РАН. В качестве объекта исследований использовали зерно белого люпина сорта Дега. Эксперименты по изучению условий измельчения зерна проводились на лабораторной молотковой дробилке с регулируемой частотой вращения ротора. Рассматривалось влияние влажности зерна, скорости молотков и диаметра отверстий рабочего сита дробилки на выход крупки и содержание в ней недоруша (зёрен и частиц с остатками оболочки, крупных частей неотвеянной оболочки). Использование простой технологической схемы обрушения зерна белого люпина на базе молотковой дробилки позволило получить до 70% крупки с повышенным содержанием белка и низким содержанием клетчатки. С ростом скорости молотков и уменьшением диаметра отверстий рабочего сита дробилки выход крупки снижался, что объяснимо ростом доли мелкой фракции, которая отвеивается при пневмосепарации. Крупка представляет из себя частицы ядра с недорушем, а относы являются смесью дроблёной оболочки с мучкой — мелкой фракцией дробленого ядра. Основная доля мучки ядра была сосредоточена во фракции меньше 1,5–2,0 мм, в которой содержится больше белка. Данная фракция составляла около половины массы относов или около 15% от массы зерна. Наличие недоруша в крупке повышало содержание в ней клетчатки и снижало содержание белка. С ростом влажности и диаметра отверстий рабочего сита дробилки содержание недоруша возрастало, а при росте скорости — падало. При фиксированной влажности содержание недоруша можно снизить за счёт повышения скорости удара (увеличения числа оборотов) или уменьшения диаметра отверстий рабочего сита дробилки, но и тот и другой метод повышают энергозатраты. При возрастании скорости удара росла и производительность. The research was conducted in 2019. Hammer grinder with adjustable rotor speed was used to crush the grain of white lupine “Dega”. The effects of grain water content, crushing speed and sieve size were analyzed on grain crushing and hulling as well as the proportion of unhulled grain. This technology resulted in up to 70% of crushed hulled grain rich in protein but poor in fiber. Increase in hammer speed and decrease in sieve size negatively affected the proportion of crushed grain due to the high content of fine fractions discarded further via pneumatic separation. Crushed hulled grain is normally combined with unhulled grain. The mixture of crushed hulls and fine particles of crushed grain are to be separated. Most of the bran was found in the fraction of 1.5–2.0 mm containing more protein. This fraction amounted to 15% of grain mass and 50% of the mass to be discarded. Unhulled grain mixed with crushed hulled grain increased fiber content in the mixture but reduced protein concentration. Higher grain water content and larger sieve size increased the amount of unhulled grain, while higher hammer speed decreased its fraction. Higher hammer speed as well as smaller sieve size reduce the content of unhulled grain but increased energy costs under constant grain water content. Increase in hammer speed improved the capacity of the grinder.

How do spatial throughfall patterns reflect in soil moisture patterns?

<div> <p>This study investigates whether and how vegetation cover affects the spatial heterogeneity and vertical penetration of water through the Upper Critical Zone (UCZ). We assessed rainfall, throughfall and soil water contents on a 1‐ha temperate mixed beech forest plot in Germany. Throughfall and soil water content in two depths (7.5 cm and 27.5 cm) were measured on an event basis during the 2015 - 2016 growing season in independent high‐resolution stratified random designs. We calculated the increase of soil water content (Δθ) due to the rainfall by the difference between measurements at the beginning (pre-event) and the maximum soil water content after the end of rainfall event (post-event). Since throughfall and soil water content cannot be assessed at the same location, we used kriging to derive the throughfall values at the locations where soil water content was measured. We explore the spatial variation and temporal stability of throughfall and soil water content and evaluate the effects of throughfall, soil properties (field capacity and air capacity), and vegetation parameters (next tree distance) on soil water content variability.</p> <p>Throughfall patterns were related to canopy density although correlation length decreased with increasing event size. Temporal stability was high, leading to persistently high and lower input locations across rainfall events.</p> <p>A linear mixed effect model analysis confirmed that the soil water content increase due to precipitation depended on throughfall patterns, in that more water was stored in the soil where throughfall was enhanced. This was especially the case in large events and in both investigated soil depths. However, we also identified additional factors that enhanced or decreased water storage in the soil, and probably indicate fast drainage and runoff components. Locations with low topsoil water content tended to store less of the available water, indicating the role of preferential flow. In contrast in subsoil, locations with high water content, and probably poor drainage, stored less water, indicating lateral flow. Also, distance to the next tree and air capacity modified soil water storage.</p> <p>Spatial soil water content patterns shortly before a rainfall event (pre-event conditions) seem to be a key factor in soil water content increase, and also explained much of soil water content shortly after the rainfall event. Pre-event soil water content was mostly driven by random local effects, probably microtopography and root water uptake, which were not quantified in this study. The remaining spatial variation was explained by air capacity in both soil layers, indicating the role of macroporosity.</p> <p>Our findings show at the same time systematic patterns of times and locations where the soil capacity to store water is reduced and water probably conducted quickly to greater depth. Not only soil moisture patterns but also deeper percolation may depend on small scale spatial heterogeneity of canopy input patterns.</p> </div>

SPECTROPHOTOMETRIC INVESTIGATION OF COBALT BROMIDE COMPLEX FORMATION IN AQUEOUS CALCIUM NITRATE– AMMONIUM NITRATE MELTS AT T = 328.15 K. INFLUENCE OF WATER CONTENT

In this work, the absorption spectra of cobalt(II) nitrate and bromide complexes in the composition 0.3Ca(NO3)2 – 0.7NH4NO3 – H2O have been investigated in the 400-800 nm range of wavelength at T = 328.15 K and atmospheric pressure P = 101.3 kPa. Spectra were recorded in solutions with variable water content (R = H2O/salt mole ratio; R = 1.0, 1.2 and 1.6). The blue shift of the absorption maximum with the water content increase (R) suggest simultaneous coordination by water molecules and nitrate ions. From an analysis of the spectra, it can be concluded that the following: [Co(NO3)4(H2O)2]2−, [Co(NO3)2Br2]2− and [CoBr4]2− complexes were formed. The overall stability constants of these complexes species spectra were calculated at T = 328.15 K.

Search Ferments from Microorganisms Isolated from the Sap of the Oil Palm (Elaeis guineensis)

The aim of this study is the search for ferments from microorganisms isolated from the sap of the oil palm. It consisted in determining, before and after 24 hours of fermentation, the physicochemical and microbiological parameters of palm wine using standard methods. The pH, the rate of reducing sugars and the dry matter levels decrease while the acidity, vitamin C and the water content increase after 24 hours of fermentation. The pH decreases from 3.56±0.01 to 3.24±0.01 in Dura palm wines with the Pisi Sab S10 microorganism, while in Pisifera wine this pH increases from 3.93±0.01 to 3.82±0.01 with Pisi Sab 30S3. The titrable acidities increase from 0.71%±0.01 to 0.79%±0.01 in the sap of the Dura palm with the Pisi Sab S10 microorganism, while in the wine of Pisifera the rate increases from 0.67%±0.01 to 0.76%±0.01 with the microorganism Pisi Sab 30S3. Reducing the levels of sugar decrease to minimum values. They increase from 86.34±0.02 to 42.05±0.01 mg/mL in the sap of the Dura palm with the Pisi Sab S10 microorganism, whereas in that of the Pisifera wine, the rate increases from 32.07±0.02 to 14.53±0.02 mg/mL with the Pisi Sab 30S3 microorganism. The level of alcohol increases to reach maximum values of 4.24%±0.01 with the Pisi Sab S10 microorganism in Dura palm sap and 4.29%±0.01 in Pisifera sap with the Pisi Sab microorganism. 30S3. The microorganism giving the best organoleptic qualities in the sap of the Dura palm is Pisi Sab S10 while that of Pisifera is Pisi Sab 30S3. These microorganisms thanks to their efficiencies could be used as ferments in the agro-food industries.

Water Content Influence on Properties of Red-Layers in Guangzhou Metro Line, China

In order to reveal water content influence on shear strength, swelling, and creep properties of red-layers in Guangzhou Metro, Southern China, the typical red-layers rock and soil specimens were experimentally studied by direct shear test, UU triaxial test, swelling test, and creep test, and the measured data were analyzed. The results showed that soil internal friction angle exponentially decreased with the water content increase and cohesion in accordance with the Gaussian function firstly increased and then decreased with the increase of water content. Expansion rate significantly decreased with the initial water content increase. The red sandstone had very strong isotropic expansion and disintegration properties. The mechanism of water content effect on red-layers properties was water induced microstructures and mineral compositions change which caused the macro physical and mechanical characteristics degradation. The results should provide the reference for further research for water induced damage mechanism or creep damage control of red-layers in engineering practice.

Research on Stability Mechanism of Fissured Loess Slope Influenced by Rainfall and Evaporation

Based on saturated-unsaturated seepage mechanism, the features of pore-water pressure, strain and displacement of fissured and fissureless slope are analyzed by using the finite element method. At the same time, pore-water pressure, displacement and safety factor of fissured and fissureless slope as well as fissured slope with different depth and width are comparatively analyzed under the condition of rainfall and evaporation. The research results show that, under rainfall condition, the existence of fissures could change the boundary of soil infiltration and seepage filed distribution, lead to stress concentration and make plastic strain around the fissures area. In addition, as the rainfall response time increasing, the plastic zone around the fissures will spread to the surrounding, thus, the new micro-fissures would be produced during the process of the fissures expansion. Evaporation will reduce the shallow soil water content, increase suction and slope stability. Under the condition of rainfall and evaporation, slope stability is affected more seriously by the fissure depth, but less by the width.

Pullout Tests Study on Performance of Interface between Geogrid and Soil

The interface interaction between geogrid and soil is one of key issues on stability of geosynthetic-reinforced soil structures. Comparative analysis of properties of geogrid-clay interface under the different kinds of geogrid, different normal stresses, speeds of pullout and water contents of clay are conducted by medium-sized pullout tests. The tests results showed that ultimate pullout force of geogrid, interfacial cohesion and frictional coefficient are significantly affected by various water contents of clay. Ultimate pullout forces of geogrid tending to remarkably difference when subject to different normal stresses at lower water contents, and frictional coefficient of interface decrease with the increase of water content, interfacial cohesion has a tendency to increase followed by decreasing with increase of water contents. Moreover, the curves of load and displacement possess three piecewise consisting of linear increase, non-linear increase and ultimate pullout, and as water content increase interval nonlinear changing stage is not conspicuous.