Experimental Study on the Crushing Properties of Corn Stalks in Square Bales

With the development of straw baling mechanization technology, straw is stored in the form of square baling or round baling. At present, hammer mill or the guilt-cutting and rubbing combined mill is widely used to crush square bales of straw. These two kinds of crushing equipment have disadvantages such as low productivity, large power consumption, and poor crushing effect. This paper aims to study and analyze the crushing characteristics of square baled straw after unbaling, and lay a theoretical foundation for the later research and development of a special square baled straw crusher with high productivity, low power consumption, good crushing effect, and the simulation of the square baled corn straw crushing process. For this purpose, this study carried out a corn bale crushing experiment on the Instron 8801 fatigue test machine, and studied the effects of blade angle, water content and loading speed on corn bale crushing force through the response surface method. Test results showed that the crushing process includes the compression stage and shearing stage; in terms of single factor effect, with the increase in water content and blade angle, the crushing force of the corn bale increased, but the loading speed had no significant effect on the crushing force of the corn bale. In terms of interaction effect, there was interaction effect between moisture content and blade inclination angle, when moisture content was 10%, with the increase in blade inclination angle, the incremental speed of the crushing force also increased gradually. When the blade inclination angle was 10°, with the increase in moisture content, the incremental speed of the crushing force also increased, and the interaction effect of them jointly acted on the crushing force of the corn bales.

The importance of the size of the trunk inclination angle in the early detection of scoliosis in children

Background Early detection of idiopathic scoliosis is one factor in determining treatment effectiveness. Therefore, the aim of this study was to assess the importance of the size of the trunk inclination angle (ATI) for the early detection of scoliosis in preschool- and school-age children, taking into account the location and size of the spine curvature. Methods The study included a group of 216 children (mean age 11.54 years, standard deviation ± 3.05), who had previously untreated idiopathic scoliosis and a Cobb angle of ≥ 10°. The ATI values were compared with the corresponding Cobb angle values. The results of the ATI-Cobb correlation were compared to the ATI thresholds of 5° and 7°. Results In the age groups 6–9, 10–12 and 13–17 years, the method sensitivity for the ATI ≥ 7° criterion was low at 33.90%, 27.69% and 51.29% (p < 0.05), respectively, while for the ATI ≥ 5° criterion, it was 67.8%, 69.23% and 93.48% (p < 0.05), respectively. With respect to location, significantly more frequent misdiagnoses (p < 0.05) were related to the lumbar and thoracolumbar (regions) sections of the spine in the groups aged 6–9 and 10–12 for ATI ≥ 7°; while no significant relationship was found at ATI ≥ 5°. For both ATI levels, the most frequent cases of mis- or undiagnosed scoliosis were observed among children with a Cobb angle of 10°-14° (p = 0.004). Conclusion A low predictive ATI value was demonstrated regarding scoliosis detection for the ATI 7° criterion in children aged 6–9 and 10–12 years, particularly for the lumbar and thoracolumbar locations. Adoption of the threshold of ATI 5° in screening tests for children aged 6–12 years, as well as for lower locations of scoliosis, may be more effective in the early detection of scoliosis. Trial registration. This study was approved by the Jan Dlugosz University in Czestochowa Ethics Committee KE-U/7/2021, and conducted under the Declaration of Helsinki.

Effects of a Verbal Intervention for Head and Neck Posture on Lumbar Lordosis Angles in Healthy Young and Older Adults: a Preliminary Study

Background Postural rehabilitation plays an important role in the treatment of non-specific low back pain. Although pelvic inclination has been widely used to improve lumbar lordosis, the effect of cervical anterior inclination on lumbar lordosis in young and older adults, in sitting and standing posture is still unclear. This preliminary study was designed to examine the influence of changing the cervical anterior angle on the lumbar lordosis angle, through alterations of the head position under the natural sitting and standing conditions, aiming to provide a basis for establishing a new postural rehabilitation strategy.Methods Thirty-eight older (68.4 ± 5.9 years old) and 36 young (24.0 ± 2.2 years old) healthy adults participated in this study. The four spinal regional angles - cervical anterior angle, thoracic kyphosis angle, lumbar lordosis angle, and pelvic foreword inclination angle were measured in standing and relaxed sitting postures to determine the effects of a postural cueing, “inclining head backward and performing chin tuck”, for the head and neck posture on lumbar lordosis angle.Results In the standing posture, the pelvic foreword inclination angle in the older group was significantly smaller (P <0.001) than that in the young group, and increased significantly (P <0.001) post the postural cueing. In addition, the thoracic kyphosis angle in the standing (P = 0.001) and sitting (P = 0.003) positions was significantly reduced post the postural cueing. However, the lumbar lordosis angle post postural cueing increased significantly in both the standing position (P <0.001) and sitting position (P <0.001).Conclusion The results suggest that increasing the cervical anterior angle can indeed increase the lumbar lordosis angle, and the cervical anterior inclination can be used as an alternative to pelvic foreward inclination to improve the lumbar lordosis angle. Furthermore, the change of head and neck posture can reduce the thoracic kyphosis angle, making it possible to establish a new non-invasive body posture rehabilitation strategy.(approval number TJUS2019032)

Dust Structure Nearby G229-03

The Sky View Virtual Observatory was used for the systematic search of dust structures within the far-infrared loop G229-03. The source (object) responsible for the formation of the cavity of interest was detected by the Set of Identifications, Measurements, and Bibliography for Astronomical Data (SIMBAD) database. The total mass of the loop was 8.50031 × 1029 kg which is about 0.425 times the mass of the Sun at a distance of 1300 pc. The size of the cavity was 3.67° × 3.6°, whereas its core size was 0.531° × 0.255° located at R.A. (J2000) = 7h10m0.8s and Dec.(J2000) =15h55m30s. The minimum and maximum temperatures were between 20.24 ± 1.16 K and 18.63 ± 1.96 K respectively. In the core region, the average temperature was 19.53 K, approximately equal to Gaussian center 19.267 K with an offset temperature of 0.4 K showing that the core region of the cavity is dynamically stable. The Far-infrared loop was found to be located within a 1° radius around the high-velocity cloud HVC oriented by 45° to the plane of the sky. The inclination angle of the core of the loop was greater than 60° whereas the inclination angle for the larger structure was 13.71°. The Gaussian distribution of temperature was well fitted with the center of 19.267 K which shows that the cavity was in thermal equilibrium and the outer region with offset temperature of about 35 K suggesting that the loop was dynamically unstable possibly due to high-velocity cloud

RESEARCH ON THE UNIFORMITY DEGREE OF SOLID ORGANIC FERTILIZERS DISTRIBUTION

In this paper are presented the results of experimental research conducted in order to improve the uniformity of organic fertilizers distribution (compost and semi-fermented manure) used for soil fertilization, if the administration is done with a machine with a distributor with continuous spiral centrifugal beaters, arranged vertically. The uniformity of organic fertilizers distribution depends on a number of factors such as: the speed and angle of inclination of the distribution device, the distance between the distribution beaters, the humidity and the density of the material, wind speed, the size of the fertilizer particles. The determinations were performed under working conditions and the various parameters were the beaters speed, beaters inclination angle and the feed rate of the distribution device, choosing 3 situations (minimum, average and maximum) for each of them. Based on the obtained results, the multivariable functions of polytropic form was determined, which characterize the degree of uniformity of the spread material, function that can be the basis for the elaboration of constructive solutions to ensure the optimum uniformity of distribution.

Wall Pressures In a Channel Flow Obstructed By a Line of Inclined Rods: Invariant Groups and Semi-Empirical Correlations

An experiment is conducted in a rectangular channel obstructed by a transverse line of four inclined cylindrical rods. The wall pressure around the perimeter of a central rod and the pressure drop through the channel are measured varying the inclination angle of the rods. Three assemblies of rods with different diameters are tested. The measurements were analyzed applying momentum conservation principles and semi-empirical considerations. Several invariant dimensionless groups of parameters relating the pressure at key locations of the system with characteristic dimensions of the rods are produced. It was found that the independence principle holds for most of the Euler numbers characterizing the pressure at different locations, that is, the group is independent of the inclination angle provided that the inlet velocity projection normal to the rods is used to non-dimensionalize the pressure. The resulting semi-empirical correlations can be useful for designing similar hydraulic units.