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81.
为提高装配式木结构中异形柱的力学性能,设计了一种用热压等边角钢和SPF集成材为原料,环氧树脂胶黏剂连接制作的角钢-集成材L形组合柱,作为框架结构或框架剪力墙结构的角柱。以角钢边宽度对L形柱正截面承载力的影响进行了轴压试验研究,并进行ANSYS有限元模拟,以判断模拟预测的准确性。结果表明:角钢-集成材L形组合柱相对于同截面面积的木柱而言承载能力上升37.0%~51.4%,刚度上升36.5%~72.8%,同时L形柱有良好的延性;适当增加L形柱中的角钢边宽度可以使承载能力有效提高,但是其短边处的集成材易产生破裂,增加试件的脆性破坏;集成材之间的环氧树脂胶合界面在破坏前后都性能良好,在材料弹性阶段钢材和木材有效共同受力,承载力计算时需要考虑钢材的塑形增强作用;ANSYS有限元模拟的角钢-集成材L形组合柱弹性模量结果和试验结果一致,误差在10%以内,模拟结果基本可靠。研究成果对于预测角钢-集成材L形组合柱在实际预制装配时的安全可靠性提供了理论依据。 相似文献
82.
In order to determine the effects of ghost fishing by lost gill nets, the relationship was examined between soak time and
number of enmeshed animals in experimentally lost gill nets by using diving observations. Two experimental gill nets were
set at 13 m depth in Tateyama Bay, Chiba Prefecture, Japan for approximately 200 days. One gill net was deployed in a small
trough surrounded by artificial reefs, and the other was deployed on an adjacent open sandy bed. Twelve species of crustaceans,
six species of gastropods, and five species of bony fish were enmeshed in the experimental gill nets. The number of enmeshed
animals in the artificial reef gill net was substantially larger than that in the sandy bed gill net. The number of enmeshed
animals in the experimental gill nets increased rapidly within one month after deployment, and then declined gradually showing
fluctuations caused by the decrease in newly enmeshed animals, and the drop off from gill nets caused by the decomposition
of dead animals. The decrease in the number of enmeshed animals was expressed by logarithmic equations, and based on these
equations, the duration of capture function for the lost gill nets was calculated to be 284–561 days in the artificial reef
gill net and 200 days in the sandy bed gill net. The duration of capture function for the lost gill nets for non-commercial
by-catch species such as small crustaceans and gastropods was longer than for commercial species such as Japanese spiny lobster
and bony fish. 相似文献
83.
84.
王忠霞 《农业图书情报学刊》2010,22(11):253-254,257
利用调查分析的方法对2009年《图书馆学刊》栏目设置情况进行了详细的描述,《学刊》栏目数量适当,结构合理,展示了整体性、灵活性和科学性的特点,突出了学术性、先进性和继承性的特色。 相似文献
85.
运用高效液相色谱法测定福建参薯类山药资源的尿囊素含量,以检测比较不同参薯类山药资源的尿囊素含量。结果表明:在相同栽培条件下,不同产地山药的尿囊素含量存在一定的差异;采用YMC ODS-AQ色谱柱,尿囊素在0.3~2.1 μg间线性关系良好,回收率为96.4%(RSD=2.4%),精密度良好(RSD=1.2%),样品提取液在10 h内稳定(RSD=2.0%)。该方法简便可靠,可作为山药质量控制的检测手段之一。 相似文献
86.
《Communications in Soil Science and Plant Analysis》2012,43(22):2947-2963
A soil column laboratory experiment was carried out at the central campus, Mahatma Phule Agricultural University, Rahuri, India during 2008–2009 to study the accumulation and mobility of salts in Typic Haplusterts as influenced by primary biomethanated spentwash (PBSW). The PBSW was applied in three different levels (0.5, 1.0, and 2.5 cm) and then tap water with low salinity and low sodium hazard (C1S1 class) was used to carry out leaching in four different levels of water at the pore volume of soil (WPVS) (0.5, 1.0, 1.5, and 2.0). The electrical conductivity (EC) in the soil increased significantly with increasing levels of PBSW and decreased with increasing levels of WPVS in surface (0–15 cm deep) and subsurface (15–30 cm deep) soil layers. The exchangeable calcium (Ca2+), magnesium (Mg2+), and potassium (K+) increased, whereas exchangeable sodium (Na+) decreased with increasing levels of PBSW and WPVS in surface and subsurface layers of soil. The organic carbon content increased with increasing levels of PBSW and decreased with increasing levels of WPVS in both the soil layers. The cation exchange capacity (CEC) increased with increasing levels of PBSW and WPVS in both the soil layers. The exchangeable sodium percentage (ESP) decreased with increasing levels of PBSW and WPVS over the initial values of soil in both the layers. The pH of saturated paste (pHs) was reduced and electrical conductivity of extract (ECe) was increased with increasing levels of PBSW and WPVS in both the layers. The Na+ content of saturation paste extract increased significantly with increasing levels of PBSW and WPVS in both the soil layers. 相似文献
87.
88.
The shortcomings of the present two formulae for describing column holdup are analyzed and deductions are made to find a new formula. The column holdup, Hw, described by the new formula is dimensional,and related to soil solute transport kinesis and column physical properties. Compared with the other two column holdups, Hw is feasible to describe dimensional column holdup during solute transport process. The relationships between Hw and retardation factor, R, in different solute transport boundary conditions are established. 相似文献
89.
Lappalainen A Norrgård M Alm K Snellman M Laitinen O 《Acta veterinaria Scandinavica》2001,42(2):229-236
The vertebral column of 124 randomly selected miniature dachshunds, representing 4.5% of the population registered by the Finnish Kennel Club during the years 1988 to 1996, were radiographed. The front legs were also radiographed in order to evaluate the curvature of the radius and ulna. Calcified discs were found in 75.9% of the longhaired miniature dachshunds and in 86.7% of the wirehaired ones. The occurrence of signs associated with IDD was 16.5% in longhaired and 15.6% in wirehaired miniature dachshunds. The occurrence of signs of IDD in dogs with calcified discs was 20.0% and 17.9% in longhaired and wirehaired miniature dachshunds, respectively. In dogs without calcifications only one dog showed signs of IDD. The curvature of the radius and the ulna did not differ between the dogs with signs of IDD and the healthy ones, or between the dogs with and without intervertebral calcifications. Our results indicate that radiographic eradication based on the presence of intervertebral calcifications is not suitable for breeding purposes for the Finnish miniature dachshund population because the percentage of dogs without calcifications is small. 相似文献
90.
B.P.A. Fonseca MS A.L.G. Alves PhD J.L.M. Nicoletti PhD A. Thomassian PhD C.A. Hussni PhD S. Mikail DVM 《Journal of Equine Veterinary Science》2006,26(11):507-516
The object of the current study was to evaluate the efficacy of thermography and ultrasonography in the diagnosis of thoracolumbar lesions in Quarter Horse athletes and associate the different types of lesions found with the athletic modality practiced. Twenty-four horses were admitted to the Surgery Service for Large Animals of the Veterinary and Animal Science Faculty, UNESP, Botucatu, Brazil, with complaints of back problems. All the horses were submitted for physical examinations to confirm the existence of thoracolumbar alterations and then for thermography and ultrasonography. Thermography was used to map the lesioned areas of this region and ultrasonography for lesion characterization. The lesions found were supraspinous desmitis, interspinous desmitis, dorsal intervertebral osteoarthritis, and impingement of the spinous processes or kissing spines. The existence of a relation between the type of event practiced by the horse and the type of lesion found was determined. In horses that competed in the barrel race, a predominance of lesions in the thoracic caudal, thoracolumbar, and cranial lumbar regions occurred, with intervertebral osteoarthritis and interspinous desmitis being the most common. In cutting horses, most of the lesions were observed in the caudal lumbar region, whereas horses competing in reining showed a preferential location for lesions in the middle lumbar, with a predominance of supraspinous desmitis and myositis. Thermography associated with ultrasonography was shown to be efficient in the diagnosis of the thoracolumbar lesions of these horses. 相似文献