对拉巴汽车雨刮间歇继电器的测试与研究

对匈牙利的拉巴(RA′BA)重型汽车所采用的西德Bosch公司生产的雨刮系统间歇继电器作了各种档位、喷水与不喷水等多种工况的测试;发现了几个新问题,根据试验结果分析原理;引出故障诊断的思路。     

Effect of intermittent starvation on growth and some antioxidant indexes of Macrobrachium nipponense (De Haan)

The effect of different periods of starvation (0, 2, 4 and 8 days) followed by re-feeding on growth, feed utilization, oxygen consumption and some immune indexes [reactive oxygen intermediates (ROIs), activities of superoxide dismutase (SOD) and catalase (CAT)] was evaluated over an 18-day experimental period in shrimp Macrobrachium nipponense (De Haan) that had an initial body weight of 0.52 g. As a result of compensatory growth, indicated by an increase in specific growth rate (SGR), feeding rate (FR) and feed conversion efficiency (FCE) after re-feeding, final body weight of shrimp starved for 2 days (0.63 g) and 4 days (0.65 g) did not differ ( P >0.05) from the control group (0.64 g), with feed withholding for 8 days presenting a significant lower value (0.63 g). Oxygen consumption rate (OCR) decreased during the starvation period in all groups, followed by a gradual increase to a similar ( P >0.05) value than found in the control group (0.47 mg kg⁻¹ h⁻¹) at the end of the experiment. Although ROIs and the activity of SOD and CAT fluctuated during starvation in the feed-deprived groups, values at the termination of the experiment were comparable ( P >0.05) to those found for the control group.     

Assessment of marine thraustochytrid <Emphasis Type="Italic">Schizochytrium limacinum</Emphasis> OUC88 for mariculture by enriched feeds

ABSTRACT:   In the present study, Schizochytrium limacinum OUC88, a thraustochytrid with high content of docosahexaenoic acid (DHA, 22:6 n −3), was used as feed for rotifer Brachionus plicatilis and Artemia franciscana . The rotifer and Artemia were harvested at 3, 6, 9, 12, 18, and 24-h intervals, analyzed for fatty acid composition, and compared with the control which fed on yeast only. The highest DHA content resulted from an enrichment period of 12 h for both fed organisms, reached 13.4 and 10.9% of the total fatty acids (TFAs) in rotifers and Artemia nauplii, respectively, and the DHA level reduced sharply if enrichment time was longer than 12 h. The pseudoalbinism rate of turbot Scophthalmus maximus juveniles fed enriched rotifers and Artemia nauplii reduced greatly (40% lower than in control group). Thus, enrichment of rotifers and Artemia nauplii by DHA-rich Schizochytrium limacinum OUC88 may provide a practical strategy for feeding fish juveniles in aquaculture.     

两相邻边固定两相邻边简支弹性薄板的两类变量广义变分原理

按照广义力和广义位移之间的对应关系,将弹性薄板的平衡方程和几何方程乘上相应的虚量,然后积分,代数相加,代入本构关系,进而建立两相邻边固定两相邻边简支弹性薄板的两类变量广义势能原理。通过代入另一类本构关系,再应用类似如上的方法,建立两相邻边固定两相邻边简支弹性薄板的两类变量广义余能原理。再将这两种两类变量的广义变分原理分别退化到弹性薄板的势能原理和余能原理。最后,应用两类变量广义余能原理求解弹性薄板的挠度。     

试析凯文·林奇在《城市意象》中是如何显现思维的存在并使之导向真实的

思维与对象的直接联系才能产生真实的发展与研究。为能显现思维的存在并使之导向真实,作者从思维的主体观察者和主体的观察对象环境两方面寻求着解决方法。     

压力实时监测法在管道泄漏检测中的应用

检测输油管道漏油的方法很多，介绍了通过压力实时监测确定输油管道漏油点方法，以及实际应用情况。实践证明，通过压力实时监视确定输油管道漏油点的方法在实际输油运行中是切实可行的。     

吉林省镇赉县林业生态建设现状及发展对策的研讨

林业是生态环境建设的主体,本文就镇赉县林业生态建设现状及发展对策进行了阐述。     

Character of viral clones in serial passage of a nuclear polyhedrosis virus in vitro

In this paper,the character of viral clones from early and late passages after serial passages of Trichoplusia ni single nuclear polyhedrosis virus in a Tn 5B1-4 cell line is described.It demonstrated that no significant difference was observed in the infectivity of the cell culture supernatants of various passages to the cell line.The number of polyhedra produced in a cell and infectivity of polyhedra to T.ni larvae declined strikingly with the increase of passages.The polyhedra without virions began to increase from passage to passage.The result of restriction enzyme digestion showed that the DNA restriction fragments of the clones were different from wild virus DNA,although they came from a homogeneous viral DNA.The mutation of viral DNA resulted in the in crease of noninfectious polyhedra without virions and in the increase of the number of polyhedra produced in cell line as well as virulence of the polyhydrosis inclusion bodys to T.ni larvae after prolonged passages of Tn SNPV in the cell culture.     

动力负熵场及其在短期天气预报中的应用

把纬圈气流虚拟平衡态原理具体应用到短期预报中,因时效短的缘故,决定了虚拟平衡态应在低层大气中寻找,倘若时效达到一定天数,则平衡态应在中层大气中定义。按照涡动原理计算出动力负熵值,由动力负熵值构成动力负熵场,其由正熵区,负熵区、０值线三部分组成,正熵区为无降水区,负熵区又分为负熵有效区和负熵无效区,前者为未来的降水区域,降水强度与负熵中心值和梯度的大小成正比。     

基于SfM的城市树木参数提取研究

通过在城市森林样地水平的树干三维模型重建与估算胸径试验（半径6 m圆形样地）,研究运动恢复结构（SfM）算法在城市森林调查中应用的可行性,并将SfM算法得到的胸径与手持式激光雷达结果进行比较。结果表明：在胸径估算结果上,SfM算法的rRMSE为5.38%（rBias=2.74%）,手持式激光雷达的rRMSE为3.35%（rBias=1.04%）,2种方法的估测值均与野外实测值高度呈正相关（R²大于0.97）,满足树木参数提取精度要求。SfM算法成本低、易操作,具有创新意义,且估算树干胸径在森林资源调查允许误差范围内,在城市森林资源调查中具有一定应用价值。