高产耐裂西瓜新品种‘美胜’

‘美胜’西瓜是以‘花早绿’为母本,‘904-2-1-M’为父本杂交选育出的耐裂、高产杂交一代新品种。果实圆形,底色深绿,覆清晰的墨绿条带,条带数14～16条,有蜡质层;瓜皮厚1 cm,韧性好,耐储运;瓤色红,沙脆,纤维少,口感好,中心可溶性固形物含量11.1%;果实发育期30 d,平均单瓜质量7.4 kg,平均产量75 570 kg·hm^-2。适宜河北省早春拱棚种植。     

NAVICULAR BONE FRACTURE IN THE PELVIC LIMB IN TWO HORSES

The case history, radiographic and scintigraphic findings of two horses with pelvic limb navicular bone fractures are presented. In both cases the fractures were of traumatic origin. One horse had a bilateral fracture of the navicular bone, distal border, the other horse had a fracture of the proximal articular border in one pelvic limb navicular bone.     

Femoral diaphysis fractures in cattle: 26 cases (1994–2005)

Objective   This retrospective study was conducted to evaluate the outcome for cattle with diaphyseal fractures of the femur, but not including capital physeal injuries.
Methods   Sources of information were medical records of cattle having a definitive diagnosis of diaphyseal femoral fractures and telephone survey of owners.
Results   Medical records for 26 cattle with femoral fracture were found; of the 20 aged less than 2 months, 15 were treated surgically, 4 conservatively (stall rest) and 1 was euthanased without treatment. The surgical treatment varied according to the configuration of the fracture and the surgeon's experience. Surgery for mid-diaphyseal fractures had a significantly better surgical outcome then distal diaphyseal fractures (P < 0.05), as there were significantly fewer postoperative complications. Of the 15 calves treated surgically, 10 were discharged from hospital and 5 were retained in the herd without noticeable lameness. Of the 4 calves treated conservatively, 3 were alive at follow-up, but 2 were still lame. Of the 6 older cattle, 3 were euthanased without treatment and 3 were treated conservatively, 2 of which were alive at follow-up but 1 was still lame.
Conclusion   Conservative treatment of femur fracture in cattle is possible but associated with complications during the convalescence. Continued research is needed to optimise distal diaphyseal fracture stabilisation in young cattle.     

Growth performance and spontaneous bone fracture incidence of turkey toms fed various levels of calcium and nonphytate phosphorus to heavy market weight

This trial evaluated the effects of various dietary calcium and nonphytate phosphorus (nPP) feeding regimens on the growth and bone integrity of Nicholas 700 toms from 2 to 19 wk of age. After a 2-wk common brooding period, 24 to 25 poults/pen were allocated to 8 pens/treatment. Crumbles were fed from 2 to 5 wk of age and pellets were fed from 5 to 19 wk of age in a 3-wk phase program. Dietary calcium was kept at a 1.8:1 ratio with nPP for all diets. Diet 1 (LOW) was formulated to provide NRC recommendations for each phase change, ending with 0.25% nPP from 17 to 19 wk of age. Diet 2 (MED) nPP levels averaged 0.06 percentage units higher than the LOW diet. Diet 3 (HIGH) averaged 0.10 percentage units higher nPP than the MED diet. Diet 4 (VHIGH) averaged 0.10 percentage units higher nPP than the HIGH diet. Body weight was decreased (P < 0.01) by the LOW diet compared with all other treatments throughout the trial. By 8 wk of age, BW was lower (P < 0.001) when the MED diet was fed compared with the HIGH and VHIGH diets. Feed:gain was worsened (P < 0.02) by the LOW diet, compared with the HIGH and VHIGH diets, throughout the entire trial. The incidences of leg problems and spontaneous bone fractures were increased (P = 0.001) when the LOW diet was fed compared with the other diets. The increase in litter phosphorus (P = 0.001) was directly proportional to increases in dietary nPP. The HIGH and VHIGH diets resulted in the best growth performance and skeletal integrity.     

油气管道计算机辅助断裂评定

管道的抗断裂性能关系到整个管道运输系统是否安全可靠，对油气输送管道进行计算机辅助断裂评定是管道系统安全运行的科学保证。利用自行开发的评定系统，对油气管道焊接接头进行了计算机辅助断裂评定研究。研究结果表明，断裂韧性、强度失配和初始裂纹状态等因素对油气管道焊接接头断裂评定具有重要影响，可为油气管道断裂评定提供科学依据。     

板结构裂纹损伤诊断研究

分析了板结构的裂纹损伤动力特性并研制了损伤诊断方法。首先以四边固支板结构为例进行裂纹损伤的动力特性分析,进而比较了裂纹损伤与局部损伤之间的联系与区别,以此为基础提出了裂纹损伤诊断的方法,并以一阶振型变化率为损伤标识量提出了裂纹损伤诊断步骤。最后应用提出的损伤诊断方法对含裂纹损伤的周边固支圆板结构进行了损伤诊断,结果显示该方法是有效的。     

基于方向滤波的成像测井裂缝检测方法研究

根据成像测井图像中裂缝具有方向性的特点,研究了一种基于方向滤波的成像测井裂缝检测方法。该算法以方向滤波为基础,根据裂缝局部方向选择相应方向滤波器进行滤波,使裂缝图像在裂缝方向上得到增强,突出了裂缝的有效信息。通过基于方向滤波与基于区域分割融合方法对提取的裂缝进行后处理,得到最终的裂缝轨迹。实际应用表明,该方法较好地检测了实测成像测井中裂缝。     

轮库输油管道的断裂失稳分析

以弹塑性断裂力学的J积分理论为基础,综合考虑裂纹的J积分弹性解和全塑性解,分析了含裂纹延性管道的弹塑性断裂问题,通过对含内表面半椭圆轴向裂纹管道的J积分弹性解和全塑性解的分析并进行迭加,得出在载荷作用下反映管道内表面半椭圆裂纹扩展能力的J积分表达式,现场断裂管道的验证分析表明,计算结果与现场事故数据基本吻合,根据相关文献,计算出轮库输油管道母材和焊缝材料的管材系数,并以试验得出的轮库输油管道的断裂韧性JIC值为依据,在上述J积分表达式的基础上,计算了含有内表面半椭圆轴向3裂纹的轮库输油管道母材和焊缝材料的临界失稳压力,为该管道在设计工况下安全运行提供了理论依据。     

ENERGY BALANCE OF HYDRAULIC FRACTURE AND FRACTURE TOUGHNESS

Based on the discussion of the phenomenon that the effect of fracture toughness is neglected in general hydraulic fracturing models, this paper gives the energy balance equation in-colding all parameters in hydraulic fracturing and proposes a method of determining the apparent fracture toughness of rock from hydraulic fracture experimental data. The discussion on the factors affecting apparent toughness indicates the inevitability that the apparent fracture toughness of rock measured by hydraulic fracture experimental data is significantly higher than that measured by the standard three-point bending method.