农药微乳剂热力学稳定性微观机制研究

 利用冷冻断裂电镜研究方法研究了表观稳定的农药微乳剂的微观结构 ,并通过光散射技术测定了O/W型微乳剂分散质点的流体力学半径 ,同时还测定了相关样品的主要表观指标。试验结果表明 ,随着微乳体系中表面活性剂 /水 (w/w)比值的减小 ,微乳剂分散质点流体力学半径变大 ,直至成为双连续结构 ,并依此提出了一种农药微乳剂热力学稳定的可能机制。这一发现使得从微观机制上解释农药微乳剂的热力学稳定性 ,指导热力学稳定的农药微乳剂的研究开发 ,并从根本上解决农药水基化制剂热贮稳定性这一关键技术问题成为可能。     

Successful outcome of a Standardbred filly after conservative treatment for a Salter–Harris type III fracture of the distal femoral condyle

A 10-day-old Standardbred filly sustained a complex Salter–Harris type III fracture of the right, lateral, distal femoral condyle. The lateral condyle was fractured in transverse, sagittal and frontal planes. The filly was treated by restricting it and its dam to a small, level paddock until lameness was no longer apparent. The filly, when weaned at 7 months of age, was turned out to pasture with three other weanlings. The filly entered race training as a 2-year-old, qualified to race as a trotter, was placed second in its first start and won its third race. Conservative treatment should be considered as an option for a young horse with a minimally displaced, Salter–Harris type III fracture of the distal lateral femoral condyle.     

Catastrophic scapular fractures in Californian racehorses: pathology, morphometry and bone density

Reasons for performing study: To enhance understanding of the nature and pathogenesis of scapular fractures in racehorses. Hypothesis: Scapular fractures in racehorses have a consistent configuration related to sites of pre‐existing stress modelling and remodelling. Methods: Fractured and intact scapulae collected post mortem were examined visually and with computed tomography (CT). Scapular fracture configuration, bone modelling changes and standardised CT morphometry and density measurements were recorded. Statistical comparisons were made between fractured, nonfractured contralateral and control scapulae. Results: Thirty‐nine scapulae from 10 Thoroughbred (TB) and 10 Quarter Horse (QH) racehorses were obtained. All 14 fractured scapulae (from 12 horses) had a consistent comminuted fracture configuration. A complete fracture coursed transversely through the neck of the scapula at the level of the distal aspect of the spine (8.9 ± 0.9 cm proximal to the lateral articular margin of the glenoid cavity). The distal fragment of 13 fractured scapulae was split into 2 major fragments by a fracture in the frontal plane that entered the glenoid cavity (2.8 ± 0.4 cm caudal to the cranial articular margin). Focal areas of periosteal proliferation and/or radiolucency were present in the distal aspect of the scapular spine of all fractured and intact contralateral scapulae, but less commonly (P<0.01) in intact scapula from horses without a scapular fracture. Fractured scapulae had 7–10% lower mean density and 46–104% greater density heterogeneity in the spine adjacent to the transverse fracture compared to control scapulae (P<0.03). Conclusions and clinical relevance: Thoroughbred and QH racehorses have a characteristic scapular fracture configuration that is associated with pre‐existing pathology of the distal aspect of the spine. This location is consistent with scapular stress fractures diagnosed in lame TB racehorses. Catastrophic fracture is the acute manifestation of a more chronic process. Consequently, there are opportunities for early detection and prevention of fatalities.     

沧临输油管道漏油分析

通过管道许用应力计算和管道当量应力、组合应力和稳定性的验算,对发生在沧临输油管道裂口漏油的实例进行了理论分析,结果表明,输油管道的组合应力(σz)为243.5 MPa,大于管道的许用应力([σ])210.6 MPa,且水平直径方向的变形量已超过3%,管道发生断裂是必然的.并指出了同类管道在运行管理中应注意的问题.     

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。     

炭纤维增强壳聚糖内固定棒的生物相容性研究

目的:对自制炭纤维增强壳聚糖内固定棒进行生物相容性评价,为其临床应用提供实验依据.方法:采用实验动物对该内固定棒进行刺激试验与致敏试验、急性毒性试验、溶血试验,并按医疗器械生物学评价国家标准对试验结果进行生物相容性评价.结果:体内外生物相容性试验显示该材料的兔皮肤、皮内刺激未见红斑、丘疹、结节现象发生;急性金身毒性试验为阴性反应;致敏试验动物未出现过敏反应;溶血率1.64%,符合医用材料溶血率不大于5%的要求.结论:内固定棒具有良好的生物相容性,能初步满足生物内固定装置的生物相容性要求.     

Shale gas seepage mechanism and fractured wells’ production evaluation

To know the dynamic characteristics of shale gas reservoirs’ production and to improve shale gas wells production, it is very important to research on shale gas seepage mechanism and production evaluation. The main difference between shale gas reservoir and conventional gas reservoir is that shale gas reservoir has the adsorption and desorption characteristics. Combined with shale gas seepage characteristics, using point source function, the mass conservation law and Langmuir isotherm equation to describe the shale gas adsorption and desorption phenomena, it establishes dual media shale fracturing wells’ seepage model. By the numerical inversion and computer programming, it draws production decline curve charts and analysises the Langmuir volume, Langmuir pressure, elastic storativity ratio, cross flow coefficient, borders, fracture length and other factors on the impact of shale gas wells production.     

木质材料损伤断裂中声发射特性的研究进展及趋势

介绍声发射技术的定义、原理和特点,以及声发射技术作为一种新型的动态无损检测方法在木材工业中的应用,重点分析当前国内外学者对木材及木基复合材料损伤断裂中声发射特性的研究情况,指出由木材及木基复合材料损伤断裂中的声发射特性,可以在线监测木质材料裂纹尖端起裂时间、破坏源的位置以及材料损伤的严重性,较好的识别木质材料损伤断裂的不同阶段,对构件的安全性检测具有重要意义。在此基础上,指出今后声发射技术在木质材料科学领域的发展趋势。