催化裂化柴油吸附脱碱氮研究

采用吸附剂Ａ、Ｂ进行了吸附脱碱氮研究，考察了吸附剂粒度、温度、空速对碱氮脱出率的影响，并采用吸附剂Ａ进行了催化裂化柴油脱碱氮研究，通过吸附脱碱氮，催化裂化柴油的安定性得到了显著改善，柴油比色由１９降到６．     

Sparse representation and blind source separation of ill-posed mixtures

Bofill et al. discussed blind source separation (BSS) of sparse signals in the case of two sensors. However, as Bofill et al. pointed out, this method has some limitation. The potential function they introduced is lack of theoretical basis. Also the method could not be extended to solve the problem in the case of more than three sensors. In this paper, instead of the potential function method, a K-PCA method (combining K-clustering with PCA) is proposed. The new method is easy to be used in the case of more than three sensors. It is easy to be implemented and can provide accurate estimation of mixing matrix. Some criterion is given to check the effect of the mixing matrix A . Some simulations illustrate the availability and accuracy of the method we proposed.     

基于RFID的连锁超市应用系统框架设计

针对射频识别(RFID)技术应用的广泛前景,本文以连锁超市作为依托,设计了一个基于RFID的连锁超市应用系统的框架,该框架在实现普通连锁超市信息系统所具有的功能的同时,重点突出了引入RFID技术以后该应用系统所具有的新特征。     

功能化间羧基苯偶氮基杯［4］芳烃对称硫醚衍生物的制备及其对U(Ⅵ)的吸附行为研究

采用间氨基苯甲酸为原料,经重氮化-偶联反应对杯［4］芳烃进行上沿改性合成了间羧基苯偶氮基杯［4］芳烃衍生物,再通过取代反应对间羧基苯偶氮基杯［4］芳烃衍生物进行下沿修饰,制备出一种新型材料,即间羧基苯偶氮基杯［4］芳烃对称硫醚衍生物,并采用FT-IR和¹H-NMR对其进行结构表征。将该新型材料作为吸附剂用于吸附低浓度含铀水溶液中的铀,考察了溶液pH值、吸附剂用量、铀初始浓度、吸附时间、吸附体系温度等因素对其吸附性能的影响。结果表明：在铀初始浓度为10 mg/L、pH=4、温度为25 ℃、吸附剂用量为10 mg、吸附平衡时间为4 h时,间羧基苯偶氮基杯［4］芳烃对称硫醚衍生物对U(Ⅵ)的吸附效果最佳;其吸附过程符合准二级动力学模型,吸附过程为化学吸附;吸附等温线符合Langmuir吸附等温模型,说明该吸附体系是以单层吸附为主。综上所述,间羧基苯偶氮基杯［4］芳烃对称硫醚衍生物是一种潜在的铀吸附剂。     

采用铝基注塑电池架改善电池舱段散热效果的研究

当水下航行器电池舱段长时间大电流工作时,会产生大量热量,如果热量不能被快速传递到外界环境时,容易导致电池舱段内部单体电池发生短路、泄放和爆炸等安全事故[1,2],所以研究采用铝基注塑电池架改善电池舱段散热效果的可行性非常必要。首先建立了电池舱段热传递的数学物理模型;其次当电池舱段采用铝基导热塑料电池架以23 A恒流连续工作5 h时,对其内部瞬态温度和温度分布情况进行了试验测量;最后在FLUENT环境下,对几种电池架的辅助散热能力进行了数值计算。通过仔细对比试验结果和仿真结果发现,采用铝基导热塑料电池架能够显著降低电池舱段内部最高温度,满足该型水下航行器电池舱段在温度控制方面的工程要求(≤70℃),且具有一定的温度裕量。     

双站聚束SAR极坐标格式成像算法

双站聚束SAR(Synthetic aperture radar)相对于双站条带SAR可以达到更高的方位分辨率,其成像算法受到越来越多的关注.本文介绍了双站聚束SAR成像几何关系,建立了回波信号模型,从Dechirp后的回波数据域出发,提出了一种适合双站聚束SAR的极坐标格式成像算法.该PFA算法采用斜视坐标旋转及沿视线方向的极坐标插值LOSPI,更好地利用空间域数据,适用于正侧视和斜视模式成像.最后分析了距离弯曲对成像区域的限制,以及残余视频相位误差对成像性能的影响,并将此算法与不进行Dechirp的PFA算法相比较.实验结果表明该方法降低了数据率和运算量,算法有效、可靠.     

矿物油乳油有效成分的测定

参照CIPAC 29/5/(M)/5.2方法,研究了矿物油乳油有效成分测定方法,该法测定结果稳定,重复性高,变异系数在0.070 5～0.184 9,准确度大于98.66%。采用该法,国内现有该类产品标记含量可以提高1%～2%。     

Caffeine and Its Antioxidant Properties—It Is All about Dose and Source

Caffeine is the most frequently used substance with a central nervous system stimulant effect, but its consumption is most often due to the intake of foods and drinks that contain it (coffee, tea, chocolate, food supplements with plant extracts of Guarana, Mate herba, Cola nuts). Due to its innocuity, caffeine is a safe xanthine alkaloid for human consumption in a wide range of doses, being used for its central nervous stimulating effect, lipolytic and diuresis-enhancing properties, but also as a permitted ergogenic compound in athletes. In addition to the mechanisms that explain the effects of caffeine on the targeted organ, there are many proposed mechanisms by which this substance would have antioxidant effects. As such, its consumption prevents the occurrence/progression of certain neurodegenerative diseases as well as other medical conditions associated with increased levels of reactive oxygen or nitrogen species. However, most studies that have assessed the beneficial effects of caffeine have used pure caffeine. The question, therefore, arises whether the daily intake of caffeine from food or drink has similar benefits, considering that in foods or drinks with a high caffeine content, there are other substances that could interfere with this action, either by potentiating or decreasing its antioxidant capacity. Natural sources of caffeine often combine plant polyphenols (phenol-carboxylic acids, catechins) with known antioxidant effects; however, stimulant drinks and dietary supplements often contain sugars or artificial sweeteners that can significantly reduce the effects of caffeine on oxidative stress. The objective of this review is to clarify the effects of caffeine in modulating oxidative stress and assess these benefits, considering the source and the dose administered.     

Proliferating Lymphatic Endothelial Cells as a Prognostic Marker in Head and Neck Squamous Cell Carcinoma

Podoplanin and Ki-67 are two important markers of cancer progression. The aim of this study is to evaluate double immunostaining for Ki-67 and podoplanin in head and neck squamous cell carcinoma (HNSCC), and to observe the involvement of lymphagiogenesis in tumoral and peritumoral areas, as well as the density of tumor proliferation correlated with histopathological grading. A total of 50 patients with HNSCC were included in this study. We carried out a morphological evaluation of tissue samples, after that, cases were selected for double Ki-67 and podoplanin immunostaining. Podoplanin expression was significantly correlated with histopathological grade (p < 0.05; p = 0.037) and expression of Ki-67 (p < 0.05; p = 0.050). A high expression of podoplanin, as well as of the proliferation factor Ki-67, was observed in histopathological grade G3 and the correlation between these (p < 0.05; p = 0.028), and implication of LMVD and LVI was not significant (LMVD p = 0.577; LVI p = 0.976). This study demonstrated the importance of double immunolabeling in assessing lymphagiogenesis and tumor proliferation in correlation with histopathological grades in HNSCC.     

中速机连杆工艺研究及夹具设计

针对某中速机两段式连杆传统加工工艺存在的问题,通过工艺研究和夹具设计对传统加工工艺进行了改进。实际生产表明:改进后的加工工艺不仅使产品满足图纸的技术要求,而且大大提高了生产效率,降低了制造成本,符合批量生产的要求。