旋流对射流携带床气化炉内宏观混合过程的影响Ⅰ.冷态浓度分布

通过置于双通道交又射流喷嘴中心通道的旋流器产生旋流,在φ1m×4m的大型冷模装置上,测定了射流携带床气化炉内的冷态浓度分布,考察了旋流数对宏观混合过程的影响;给出了旋转射流时炉内无因次径向浓度分布、无因次最大浓度和混合分数的轴向衰减规律.     

脱氧低浓度PH_3气体熏蒸对库房杀虫效果的探讨

在脱氧条件下 ,与低浓度PH3 气体熏蒸相结合进行库房内杀虫试验 ,结果表明 ,该法操作简便、安全、经济 ,杀虫效果理想 ,且对纸质、字迹均无明显影响 .     

高效液相色谱法和薄层—紫外法测定淫羊藿中淫羊藿甙质量分数的研究

应用HPLC法测定淫羊藿中淫羊藿甙的质量分数,测得结果显示提取淫羊藿甙的质量分数与提取液关系密切,以50％乙醇提取的质量分数为最高,对同一淫羊藿药材进行质量分数测定,HPLC法操作简单,省时,分离效果好,准确度和再现性也明显优于药典的TLC－UV法。当提取方法相同时,两种方法测得的淫羊藿甙质量分数基本一致。因此,使用HPLC法也可按照药典的质量分数限度进行药材有效成分的检测工作。     

知柏地黄丸浸液对大鼠嗜铬细胞内钙的作用

运用Fura-2显微荧光测量技术,在单个大鼠肾上腺嗜铬细胞上,测量中药知柏地黄丸浸液对胞内游离钙浓度([Ca     

离子液体型表面活性剂C12mimBr与普通表面活性剂混合性质的研究

研究了离子液体型表面活性剂C12mimBr与阳离子表面活性剂Gemini 12-3-12, DTAB及阴离子表面活性剂SDS复配体系的性质, 并分别采用Rubingh-Margules模型和Rubingh-正规溶液模型计算了临界胶束浓度和混合胶团组成. 研究发现, 两表面活性剂分子结构的匹配性及带电头基之间的相互作用是影响混合溶液性质的主要因素. 对于分子结构差别较大的C12mimBr与Gemini 12-3-12的混合, 其行为远远偏离理想混合性质; 对疏水链长相同仅亲水头基不同的C12mimBr与DTAB则接近于理想混合; 而对C12mimBr＋SDS的复配体系, 正、负电荷间强烈的相互吸引使得混合体系大大偏离理想行为. 计算发现, 两种理论模型得到的混合胶团组成基本一致, 但Rubingh-Margules模型预测的临界胶束浓度比Rubingh-正规溶液模型要好     

Experimental study on a non-dilute two-phase coflowing jet: Dynamics of particles in the near flow field

The dynamics of particles in multi-phase jets has been widely studied due to its importance for a broad range of practical applications. The present work describes an experimental investigation on an initially non-dilute two-phase jet, aimed at improving the understanding in this field. A two-color PDPA has been employed to measure simultaneously the velocity and size of particles. The measurements are post-processed to check the reliability of the results and to derive information on particle volume flux as an indication of their concentration. Acoustic forcing is applied in order to control coherent structures, which are responsible for mixing and transport phenomena, and also to get phase-locked measurements. Phase-averaged statistics enabled to freeze the jet structure, not visible in the time-averaged data. The results along the jet centerline confirm that drag forces and the spread angle of the jet initially control particle dispersion, very near the nozzle exit (x/D < 4). However, as the vortical structures evolve forming tongue-shaped structures, the total particle volume flux is augmented when these structures connect with the main stream (x/D > 5). This is due to an increase of the number of smaller size particles, even when a decrease of the number of larger size particle is observed. Further analysis at five cross-stream sections across two consecutive vortices confirm that small particles are convected around the coherent structure and then incorporated to the main stream, increasing the particle concentration at the jet core. On the other hand, the number of larger particles (as well as their contribution to axial volume flux) starts to decay in regions of high azymuthal vorticity. This behaviour is partly ascribed to the transversal lift force, associated to the large spatial gradients observed in these regions. Saffman and Magnus forces have been estimated to be comparable or even greater than radial drag forces. The results suggest that the Saffman force might accelerate particles in radial direction, inducing a high radial volumetric flow rate from high to low axial velocity regions.     

钻铤螺纹的有限元分析及应力分散槽优化设计

针对钻井技术进步带来的井下钻铤的服役条件更加苛刻、失效更加严重的问题,对钻铤螺纹失效问题进行了深入分析,找出引起钻铤螺纹失效的主要原因和失效的关键部位,利用大型三维实体建模软件Pro/E和有限元分析软件ANSYS分别对API标准钻铤螺纹进行实体建模和强度分析,得出了钻铤螺纹在不同工况、不同结构条件下的等效应力分布情况,并对ZTNC56-80型钻铤螺纹应力分散槽进行了最优化研究,找出了其最优值,并指出应力的变化与过渡圆角变化不是线性对应关系,在改进钻铤螺纹应力分散槽结构时,不能单纯以增大结构过渡圆角为手段,从而为改进钻铤螺纹应力分散槽结构提供了科学依据。     

差减凝胶渗透色谱在产品浓度和品牌识别中的应用

差减凝胶渗透色谱(D-GPC)以已知的标准样品溶液作淋洗剂,样品溶液作进样试液,通过内部差减,快速准确地给出样品溶液与标准样品溶液各组分之间的差异。以聚乙二醇(PEG200)的浓度识别以及3种啤酒的品牌识别为例,通过比较常规GPC与D-GPC所得到的实验结果,说明D-GPC方法在啤酒质量控制和品牌识别等方面所具有的应用价值。     

分子动力学模拟浓度和温度对TATB/PCTFE PBX力学性能的影响

为探讨高聚物粘结炸药(Polymer Bonded Explosive, PBX)的力学性能随温度和高聚物浓度而变化的规律, 用分子动力学(MD)方法和compass力场, 对著名高能炸药1,3,5-三氨基-2,4,6-三硝基苯(TATB)与常用高聚物粘结剂聚三氟氯乙烯(PCTFE)所构成的TATB/PCTFE PBX进行模拟计算. 结果表明, 在一定范围内, 随高聚物浓度的增加, PBX的弹性系数和模量减小, 表明其刚性减小、弹性增加; 而随温度的升高, PBX的刚性减小、弹性增强. 还发现PBX的结合能随浓度增高而增大, 随温度升高而减小.     

西瓜香精的调配技术

对西瓜中所含发香成份作了分析,介绍西瓜香精的香韵组成及有选择性地使用各种单体香原料进行调配的过程,并对我国市场上西瓜香精的配制开发提出了建议。