有机肥与中微肥对晒烟品质的影响

 试验结果表明,有机肥和中微肥均能提高烟叶产量和产值,改善烟叶品质。农家肥和硼肥对降低烟碱含量和增加香气量具有较显著的效果,2种有机肥混合施用的香吃味总体协调性最好。钼肥能明显提高香气质,对改善烟叶香吃味的效果最佳;镁肥对抑制烟碱合成有一定作用。锌肥能提高香气质和香气量,对改善烟叶香吃味的作用也较大。     

图书馆——高校新生入馆教育必修第一课

新生入馆教育是高校图书馆读者服务工作的重要内容之一。论文探讨了新生入馆教育的必要性，提出了新生入馆教育的有效途径。     

Preliminary Results from the Viking X-ray Fluorescence Experiment: The First Sample from Chryse Planitia, Mars

Iron, calcium, aluminum, silicon, and sulfur are major elements in the first surface sample of Mars that has been analyzed by the Viking x-ray fluorescence spectrometer. Titanium is present in minor quantities. This is consistent with the sample being a mixture of fine silicate and oxide mineral grains, with a significant proportion of sulfates, possibly hydrated. Ferric oxide is regarded as the red pigmenting agent on the martian surface, but if it coats silicate grains, the coatings must be very thin (相似文献   

First record of the little fire ant,Wasmannia auropunctata (Hymenoptera: Formicidae), in Chinese mainland

In January 2022, we received ant specimens collected from three field colonies from Shantou City, Guangdong Province, China. They were identified as the little fire ant, Wasmannia auropunctata, through morphological and molecular analyses. Wasmannia auropunctata is listed as one of the 100 most dangerous invasive species by the International Union for Conservation of Nature (IUCN) and has spread from its native range in South America to every continent except Antarctica. DNA analysis of mitochondrial cytochrome c oxidase subunit I (COI) in nine specimens of W. auropunctata found that they had a close genetic relationship with specimens from Argentina. This study represents the first formal record of the establishment of W. auropunctata outdoor in Chinese mainland. However, the invasion stage and occurrence degree of W. auropunctata in China are not clear to date. The implementation of quarantine measures, investigation of the occurrence and distribution, and development of monitoring and control strategies are needed to actively respond to the threat posed by this highly invasive ant.     

First fossil lamprey: a record from the Pennsylvanian of Illinois

A fossil record of lampreys has previously been unknown. A new genus demonstrates the presence of this group in the Pennsylvanian. The body outline, parts of the head skeleton, rasping tongue mechanism, gill basket, and other internal organs are preserved. The fossils are very similar in structure to modern forms. The absence of hagfish characters in the fossil supports the view that the common ancestor of lampreys and hagfishes lived prior to the Pennsylvanian.