The susceptibility of hay species to mechanical damage. I. Effects of growing and curing conditions

1959 ◽  
Vol 10 (6) ◽  
pp. 788 ◽  
Author(s):  
W Shepherd

A laboratory method was developed for determining the susceptibi1ity of hay species to mechanical damage and the nature of mechanical losses likely to be encountered during field curing. Three legume species were considered: lucerne (Medicago sativa L.), white clover (Trifolium repens L.), and subterranean clover (T. subterraneurn L.). Twelve of the 17 growing and curing conditions investigated, e.g. maturity, drought, shading, and crushing, significantly affected fragility. Moisture content was particularly important and losses from carrying out field operations at unsuitable moisture contents could outweigh those from all other factors. Many types of damage contributed to the mechanical losses. Breaking up of individual leaflets, and fracture at the leaflet-petiole and petiole-stem junctions, were important but with the clovers the greatest losses resulted from fracture of petioles near the leaf-petiole junctions.

1961 ◽  
Vol 12 (5) ◽  
pp. 783 ◽  
Author(s):  
W Shepherd

Separate effects of leaf and petiole or stem moisture contents on the susceptibility of hay species to mechanical damage during field curing and storage have been investigated. Three legume species were considered: lucerne (Medicago sativa L.), white clover (Trifolium repens L.), and subterranean clover (T. subterraneum L.). Several types of damage contributed to mechanical loss. The most important over the hay moisture content ranges normally encountered during field curing and storage were the breaking up of individual leaflets, fracture at leaflet–petiole junctions, fracture of petioles, and, with lucerne, fracture of side branch stems. Leaf, petiole, and stem moistures: either separately or jointly, affected the amount of each type. Most serious losses were from the leaf portion, but under some conditions up to 25% of the shattered material petiole and stem. The amount of leaf loss was determined largely by the leaf moisture content, but under some conditions more than half the leaf loss resulted from petiole or stem fracture, which was virtually independent of leaf moisture content. Individual plants within varieties and varieties within species differed in susceptibility to the various types of damage. Differences appeared to be inherent properties of the plants or varieties, and may be considered as potentially available for incorporation into standard varieties of hay species by selection or breeding. Overall reductions in susceptibility thus available were large, e.g. at least 46% with lucerne.


1958 ◽  
Vol 9 (4) ◽  
pp. 436 ◽  
Author(s):  
W Shepherd

Moisture relations of four species used for making hay—white clover (Trifolium repens L.), subterranean clover (Trifolium subterraneum L.), lucerne (Medicago sativa L.), and perennial ryegrass (Lolium perenne L.)—have been investigated. Shapes and positions of equilibrium moisture content-relative humidity curves differed between species; and in general, moisture contents were lower for fast-cured than for slow-cured material and lower for over-mature than for less mature material. Sorption hysteresis effects were observed. Under the experimental conditions employed, equilibrium moisture contents were lower for material subjected to conditioning atmospheres immediately after mowing than for material cured prior to conditioning. Variations in the shape and position of equilibrium curves were frequently in accordance with known variations in chemical composition.


2012 ◽  
Vol 45 (3) ◽  
pp. 5-13
Author(s):  
F. Shahbazi ◽  
A Dowlatshah ◽  
S. Valizadeh

Abstract Mechanical damage of seeds due to harvest, handling and other process is an important factor that affects the quality and quantity of seeds. Seed damage result in lower grain value, storability problem, and reduced seed germination and seedling vigor and subsequent yield of crops. The objective of this research was to determine the effects of moisture content and impact energy on the breakage susceptibility of wheat and triticale seeds. The experiments were conducted at five moisture contents of 7.5, 12, 17, 22 and 27% w.b. and at the impact energies of 0.05 and 0.1 J. The percentage of breakage of both wheat and triticale seeds increased as impact energy increased. The analysis of variance showed that there was a significant difference between breakage susceptibility of wheat and triticale seeds at the 1% probability level. Triticale seeds had more breakage than wheat seeds. For both wheat and triticale seeds as the moisture content of the seeds increased, the amount of the percentage breakage of seeds decreased as a polynomial. The average values of percentage breakage of wheat seeds decreased from 43.81 to 19.88% as the moisture content increased from 7.5 to 27%. Over this same moisture content range the percentage breakage of triticale seeds varied from 81.34 to 37.77%. Below the moisture contents of 17% for the wheat and 22% for the triticale the percentage breakage of seeds increased dramatically.


2018 ◽  
Vol 40 (4) ◽  
pp. 422-427
Author(s):  
Rodrigo Albaneze ◽  
Francisco Amaral Villela ◽  
Jean Carlo Possenti ◽  
Karina Guollo ◽  
Ivan Carlos Riedo

Abstract: Mechanical damage constitutes one of the factors limiting production of high quality soybean seeds. The aim of this study was to evaluate the effects on seed viability and mechanical damage caused to soybean seeds when using a grain cart, together with an auger unloading system, as a means of transporting grain from the combine to the truck. Seed samples were collected in two seed production fields in the region of Abelardo Luz, SC, Brazil, at three different times (10:00, 12:30, and 16:00) and from three places (in the combine grain tank, in the grain wagon, and in the truck). The percentages of broken seeds, moisture content, mechanical damage to the seed coat, and germination were evaluated. The use of auxiliary grain cart equipment contributed to an increase in breakage and mechanical injury in seeds, worsening seed viability. Seeds collected at lower moisture contents had higher breakage and higher rates of mechanical damage.


2012 ◽  
Vol 45 (3) ◽  
pp. 79-86
Author(s):  
Iustina Brînduşa Ciobanu ◽  
Dana Constantinovici

Abstract Mechanical damage of seeds due to harvest, handling and other process is an important factor that affects the quality and quantity of seeds. Seed damage result in lower grain value, storability problem, and reduced seed germination and seedling vigor and subsequent yield of crops. The objective of this research was to determine the effects of moisture content and impact energy on the breakage susceptibility of wheat and triticale seeds. The experiments were conducted at five moisture contents of 7.5, 12, 17, 22 and 27% w.b. and at the impact energies of 0.05 and 0.1 J. The percentage of breakage of both wheat and triticale seeds increased as impact energy increased. The analysis of variance showed that there was a significant difference between breakage susceptibility of wheat and triticale seeds at the 1% probability level. Triticale seeds had more breakage than wheat seeds. For both wheat and triticale seeds as the moisture content of the seeds increased, the amount of the percentage breakage of seeds decreased as a polynomial. The average values of percentage breakage of wheat seeds decreased from 43.81 to 19.88% as the moisture content increased from 7.5 to 27%. Over this same moisture content range the percentage breakage of triticale seeds varied from 81.34 to 37.77%. Below the moisture contents of 17% for the wheat and 22% for the triticale the percentage breakage of seeds increased dramatically.


1986 ◽  
Vol 107 (2) ◽  
pp. 257-262 ◽  
Author(s):  
Gillian P. Whytock ◽  
Alison A. Powell

SummaryDamage to barley grain cv. Golden Promise was induced in the laboratory by putting seed at 8·7, 14, 18, 22, 26 and 35% moisture content (MC) through a mechanical laboratory thresher for 10, 20 or 45 sec. The extent of visible external damage was greatest at 8·7 and 14% MC with reduced and similar levels of damage after handling at 18–35% MC. At moisture contents up to and including 26%, seeds could tolerate extensive mechanical damage with little effect on seed quality. Seed germination and seedling vigour were, however, reduced after handling at 35% MC despite similar levels of external damage to those seeds handled at 18, 22 and 26% MC. Samples of grain of cv. Triumph produced by whole-crop harvesting included mainly slightly damaged seeds with little effect of harvest moisture content, which ranged from 22·5 to 44%, on the incidence of damage. Seed germination and seedling vigour increased when seeds were harvested at progressively lower moisture contents, with the largest increase between 36% MC (56% germination, 6·1 vigour rating) and 29·5% MC (94% germination, 7·8 vigour rating). The seed quality of whole-crop harvested seed at 29% MC was similar to that of combined seed harvested at the same moisture content. It is suggested that 30 % is the maximum harvest moisture content at which commercially acceptable seed may be produced by the whole-crop harvesting method.


Author(s):  
F. Seehofer ◽  
W. Schulz

AbstractThe phenomenon of the smoulder stream flowing through the cigarette during smouldering and during the puff intervals is demonstrated for the first time and its dependence upon physical conditions is examined. The volume of the smoulder stream can amount up to 180 ml per cigarette. Increasing draw resistance of the cigarette and augmenting moisture content of the tobacco as well as perforation of the cigarette paper have a decreasing effect on volume and velocity of the smoulder stream. The porosity of the cigarette paper has no perceptible influence. The spatial position of the cigarette affects volume and velocity of the smoulder stream. The influence exercised by the smoulder stream on the yields of total condensate, nicotine, phenols, aldehydes, and acroleine when the cigarette tip is open during the puff intervals is determined. When the moisture contents of the tobacco were extremely high, yield decreases reaching 50 % could be observed.


2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Hyeon W. Park ◽  
Jae W. Park ◽  
Won B. Yoon

AbstractNovel algorithm to determine the least cost formulation of a surimi blend was developed using linear programming (LP). Texture properties and the unit cost of surimi blend at the target moisture content were used as constraint functions and the objective function, respectively. The mathematical models to describe the moisture content dependence of the ring tensile properties were developed using critical moisture content, and the model parameters were used for the least cost LP (LCLP) model. The LCLP model successfully predicted the quality of surimi blend. Sensitivity analysis was used to obtain an additional information when the perturbations of design variables are provided. A standard procedure to determine the least cost formulation for blending surimi with varied moisture contents was systematically developed.


2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Gui-chen Li ◽  
Chong-chong Qi ◽  
Yuan-tian Sun ◽  
Xiao-lin Tang ◽  
Bao-quan Hou

The kinetics of fluid-solid coupling during immersion is an important topic of investigation in rock engineering. Two rock types, sandstone and mudstone, are selected in this work to study the correlation between the softening characteristics of the rocks and moisture content. This is achieved through detailed studies using scanning electron microscopy, shear tests, and evaluation of rock index properties during exposure to different moisture contents. An underground roadway excavation is simulated by dynamic finite element modeling to analyze the effect of moisture content on the stability of the roadway. The results show that moisture content has a significant effect on shear properties reduction of both sandstone and mudstone, which must thus be considered in mining or excavation processes. Specifically, it is found that the number, area, and diameter of micropores, as well as surface porosity, increase with increasing moisture content. Additionally, stress concentration is negatively correlated with moisture content, while the influenced area and vertical displacement are positively correlated with moisture content. These findings may provide useful input for the design of underground roadways.


2017 ◽  
Vol 57 (3) ◽  
pp. 539 ◽  
Author(s):  
P. Beck ◽  
T. Hess ◽  
D. Hubbell ◽  
M. S. Gadberry ◽  
J. Jennings ◽  
...  

The objective of this study was to evaluate the effects of including alfalfa (ALF, Medicago sativa L.) or a combination of white (Trifolium repens L.) and red (Trifolium pretense L.) clovers (CLVR) inter-seeded into bermudagrass (Cynodon dactylon L. Pers.) on herbage nutritive value compared with monocultures of bermudagrass fertilised with 0 (0N), 56 (56N), or 112 (112N) kg nitrogen (N)/ha over four grazing seasons. In autumn, at the end of the fourth year and in the spring before the fifth grazing season, alfalfa and clover plants were killed and the carryover N benefit of CLVR or ALF was compared with N fertilisation rates during the fifth year. Across years, N fertilisation rate increased herbage mass and carrying capacity linearly; whereas herbage production from CLVR and ALF swards was equivalent to 56N, were greater than 0N and less than 112N. Herbage mass in CLVR and ALF swards was greater than fertilised bermudagrass swards in the spring and did not differ from fertilised bermudagrass in the early summer. In late summer herbage accumulation of CLVR and ALF swards appeared to decrease, limiting the herbage mass in the legume pastures compared with 56N and 112N. Carrying capacity of CLVR and ALF swards was greater than fertilised bermudagrass in the spring and early summer, but did not differ from fertilised swards in the late summer. The N benefit of including legumes in bermudagrass swards can alleviate the reliance on synthetic N fertilisation with little overall effect on pasture carrying capacity.


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