On Evolutionary Sequence Systematics: Taking Permian Waagenophylloid Coral Fauna as an Example

Evolutionary sequence systematics is a discipline in paleontology and biology that deals with phylogeny of organism, the main purpose of which is to understand relatives between species and taxa and to show their evolutionary sequence. The systematics is set up on the phenetic-cladistic systematics. A number of important theoretical concepts in the cladistics are added the concept of time in the systematics. For example, the time-span between the closest sister species is considered limited in the duration of their mother species. The foundational methodology of the systematics is to analyze sister-group and character mosaic distribution, and the key to study evolutionary sequence is to understand cbaracter mosaic distribution fully. These aualyses can be executed by using computer. In the paper, the Permian Waagenophylloid coral fauna is taken as an example to illustrate the analysis on evolutionary sequence. These coral fossils are widespread in Tethyan area.Seventeen characters and a number of cbaracter states for each character used in study result from features of Waagenophylloid corals. According to principles of tbe widest distribution of character states, fossil records and ontogenesis we discerned plesiomorph character states for each character. Characters are divided into 4 ranks on the basis of their important place in pkylogeny. Based on the theory and methopology of tbe evolutionary sequence systematics the paper analyzes the sister groups and evolutionary sequence. In the examination each other between the analyses of sister groups and evolutionary sequence tbe paper found many importunt phenomena of paleontology,such as character degeneration, parallel evolution, and polydirectional clades, and distinguished a number of abnormal order. Iu the discussion to test tke rirst occurrence event8 of biostratigraphy we infer the Possible stratigraphic levels of some fossils.

Lagrangian eddies in the Northwestern Pacifi c Ocean

The Lagrangian eddies in the western Pacifi c Ocean are identifi ed and analysed based on Maps of Sea Level Anomaly(MSLA)data from 1998 to 2018.By calculating the Lagrangian eddy advected by the AVISO velocity fi eld,we analyzed the variations in Lagrangian eddies and the average transport eff ects on diff erent time scales.By introducing the Niño coeffi cient,the lag response of the Lagrangian eddy to El Niño is found.These data are helpful to further explore the role of mesoscale eddies in ocean energy transfer.Through normalized chlorophyll data,we observed chlorophyll aggregation and hole eff ects caused by Lagrangian eddies.These fi ndings demonstrate the important role of Lagrangian eddies in material transport.The transportation volume of the Lagrangian eddy is calculated quantitatively,and several major transport routes have been identifi ed,which helps us to more accurately and objectively estimate the transport capacity of Lagrangian eddies in the western Pacifi c Ocean.

Determination of time-and size-dependent fine particle emission with varied oil heating in an experimental kitchen

Particulate matter（PM） from cooking has caused seriously indoor air pollutant and aroused risk to human health.It is urged to get deep knowledge of their spatial-temporal distribution of source emission characteristics,especially ultrafine particles（UFP ＆lt; 100 nm） and accumulation mode particles（AMP 100-555 nm）.Four commercial cooking oils are auto dipped water to simulate cooking fume under heating to 255℃ to investigate PM emission and decay features between 0.03 and 10 μm size dimension by electrical low pressure impactor（ELPI） without ventilation.Rapeseed and sunflower produced high PM_（2.5） around5.1 mg/m^3,in comparison with those of soybean and corn（5.87 and 4.55 mg/m^3,respectively）at peak emission time between 340 and 450 sec since heating oil,but with the same level of particle numbers 6-9 × 10~5/cm^3.Mean values of PM_（1.0）/PM_（2.5） and PM_（2.5）/PM_（10） at peak emission time are around 0.51-0.55 and 0.23-0.29.After 15 min naturally deposition,decay rates of PM_（1.0）,PM_（2.5） and PM_（10） are 13.3%-29.8%,20.1%-33.9%and 41.2%-54.7%,which manifest that PM_（1.0） is quite hard to decay than larger particles,PM_（2.5） and PM_（1.0）.The majority of the particle emission locates at 43 nm with the largest decay rate at 75%,and shifts to a larger size between137 and 555 nm after 15 min decay.The decay rates of the particles are sensitive to the oil type.

Microtexture Evolution and Grain Boundary Character Distribution of Interstitial-Free Steels With Moderate Levels of Cold Rolling Reductions

High-strength interstitial-free steel sheets have very good deep drawability when processed to have { 111 } recrystallization texture. The microtexture evolution and grain boundary character distribution of interstitial-free steels as a function of moderate levels of cold rolling reductions were investigated by the metallographic microscopy and electron backscatter diffraction technique. The results showed that there was a close relationship between micro- texture and grain boundary character distribution for interstitial-free steel, especially the distribution and features of some specific types of coincident-site lattice boundaries. In addition, a-fiber texture was weakened to vanish while 7- fiber texture strengthened gradually as cold rolling reduction was increased from 20% to 75 % for cold rolled and an- nealed samples. Accordingly, increasing the rolling reduction from 20 % to 750% would lead to a significant increase in the proportion of ∑3 boundaries. Also, it was found that the microtexture of 20% cold rolled sample would induce a high frequency of ∑11 grain boundaries, but the microtexture of 75% cold rolled sample would produce more ∑7 and ∑17 grain boundaries. It was suggested that texture played a significant role in the formation of grain boundary character distribution.

Improving Intergranular Stress Corrosion Cracking Resistance in a Fe–18Cr–17Mn–2Mo–0.85N Austenitic Stainless Steel Through Grain Boundary Character Distribution Optimization

The grain boundary character distribution(GBCD) optimization and its effect on the intergranular stress corrosion cracking(IGSCC) resistance in a cold-rolled and subsequently annealed Fe-18 Cr-17 Mn-2 Mo-0.85 N high-nitrogen nickel-free austenitic stainless steel were systematically explored.The results show that stacking faults and planar slip bands appearing at the right amount of deformation(lower than 10%) are beneficial cold-rolled microstructures to the GBCD optimization.The proportion of special boundaries gradually increases in the subsequent stages of recrystallization and grain growth,accompanying with the growth of twin-related domain in the experimental steel.In this way,the fraction of low ∑ coincidence site lattice(CSL) boundaries can reach as high as 82.85% for the specimen cold-rolled by 5% and then annealed at 1423 K for 72 h.After GBCD optimization,low ∑ CSL boundaries and the special triple junctions(J2,J3) of high proportion can greatly hinder the nitride precipitation along grain boundaries and enhance the capability for intergranular crack arrest,thus improving the IGSCC resistance of the experimental steel.