Frequency shift domain iterative analysis for frequency estimation of equilong signals

From the view of trick recognition, features of signal decomposition structure in existing frequency estimation methods were analyzed, based on which, a frequency shift domain decomposition structure was proposed. A compound signal was constructed by combining several simple signals corresponding to different times. The given information in the time domain can be adopted to form an information accumulation effect, such that the interference frequency and noise can be suppressed effectively by decreasing the calculation. To match the use of a frequency shift domain decomposition structure, a frequency shift equilong iterative algorithm suitable for equilong signals was proposed. Simulated experiments were carried out in numerous application environments. The results show better noise immunity and real time performance as well as higher frequency estimation precision.     

Engine crankshaft static strength analysis based on the finite element method

Focusing on the fracture issue of single cylinder engine crankshafts, a three dimensional solid model was built in CATIA. Pre treatments, such as plotting grids, were carried out through Hypermesh, and finite element analysis was done using MSC. Patran/Nastran. The results show that the fatigue safety coefficient cannot meet demand when nodular iron is the crankshaft material. This finding verifies the theoretical possibility of crankshaft fracture. A crankshaft using 40Cr theoretically would not fracture because the fatigue safety coefficient could meet the demand. Simulation correctness was verified by a 400 hour engine reliability test.     

农杆菌介导的拟康氏木霉遗传转化及T-DNA插入突变体的筛选

建立并优化了农杆菌介导转化拟康氏木霉(Trichoderma pseudokoningii SMF2)获得T-DNA插入突变体的体系,在木霉孢子浓度106个/mL、农杆菌A600=0.15~0.20、乙酰丁香酮浓度为250μmol/mL的条件下共培养36 h转化率最高,转化子可达60~120个/106个孢子。共获得转化子1 000多个,连续转接5代能够稳定遗传,部分转化子表现为生长和形态异常,PCR验证潮霉素B抗性基因已整合进转化子基因组DNA中。该转化体系的建立为开展其生防机理研究和探索菌株改良奠定了基础。     

辣椒染色体倍性与气孔性状的相关性

以辣椒GT3、GT10和GT16的花药培养再生单倍体植株和其种子植株为试验材料,对叶片的气孔密度、保卫细胞叶绿体数、保卫细胞横纵径等气孔性状进行显微镜观察与统计分析.结果显示:随辣椒染色体倍性的提高,叶片气孔密度呈明显下降趋势;保卫细胞叶绿体数与保卫细胞横径呈明显上升趋势;保卫细胞纵径升高变化不明显.表明叶片气孔密度、保卫细胞叶绿体数、保卫细胞横径可作为鉴定辣椒染色体倍性的有效依据.     

次氯酸钙处理对红富士苹果常温贮藏下防御酶活性的影响

以山东红富士苹果为试材,分析次氯酸钙浸泡处理(0.15 g/L、0.60 g/L)对其常温(17～25 ℃)贮藏120 d内防御酶活性的影响,以多菌灵处理(1.00 g/L)和清水处理为对照.结果表明:次氯酸钙处理可以抑制PPO活性,总体上提高SOD、CAT和POD活性.常温120 d贮藏期间次氯酸钙 0.60 g/L 处理可以比 0.15 g/L 处理提高酶活性或峰值,但差异没有达到显著水平.     

美国临床试验信息及其检索

 

介绍了美国临床试验的概念、分期和美国临床试验信息网站（ClinicalTrials.gov）及其内

容，并探讨其检索方法。

     

试论科技查新工作与定题服务的整合

以科技查新工作和定题服务的内容为基础,对两者进行了对比分析,针对目前科技查新 工作中的问题，探讨了科技查新工作与定题服务整合的必要性和可行性，并说明了科技查新 工作和定题服务工作整合的过程中应该注意的几个问题。