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Characteristics Evaluation of Modern Bituminous Binders in Group Hydrocarbon Composition and Their Application in Construction
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作者 Vasily Koshkarov Ilya Shunyaev Evgeny Koshkarov 《Materials Sciences and Applications》 2023年第8期407-415,共9页
The article is the result of theoretical and experimental studies aimed at determining the structural groups of modern bituminous materials in order to assess the raw materials, production technology, rational directi... The article is the result of theoretical and experimental studies aimed at determining the structural groups of modern bituminous materials in order to assess the raw materials, production technology, rational directions for their use in construction, the road industry and waterproofing. Commercial oil bitumen, raw tars and heavy oil residues (semi-finished products) of oil refineries aimed at meeting large-tonnage needs have been studied. The assessment was carried out according to the group hydrocarbon composition, by liquid chromatography using model compounds. Comparative analysis showed a general trend for all studied samples of petroleum bitumen: low content of asphaltenes (from 3.9 to 23.9 wt.%), low content of resins (from 11 to 19.07 wt%), insufficient for the formation of stable structuring layers, and a significant content of aromatic hydrocarbons, including heavy aromatic compounds (more than 20 wt.%). An assumption was made about the influence of the origin and the structure obtained during the processing of asphaltenes and resins on the transition from one type of bituminous structure to another based on the lyophility of high-molecular group components. A comparative structural characteristic of heavy oil residues from gasoline and oil production is considered in comparison with bitumens of various viscosities. Recommendations are given on the technology of processing petroleum feedstock and the use of heavy oils in order to obtain a given bitumen structure for the production of rational bitumen products for construction and waterproofing. 展开更多
关键词 Bitumen TAR CONSTRUCTION WATERPROOFING Oil Refining Group Hydrocarbon Composition Viscosity ASPHALTENES
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Group Size and Composition of Black-and-White Snub-nosed Monkey (Rhinopithecus bieti) Estimated by Faecesof Sleeping Sites at Baima Snow Mountain 被引量:8
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作者 崔亮伟 钟泰 +1 位作者 肖林 肖文 《Zoological Research》 CAS CSCD 北大核心 2006年第4期337-343,共7页
This study was designed to introduce a new method of estimating group size and composition of black-andwhite snub-nosed monkeys (Rhinopithecus bieti ) on the basis of faecal amount at sleeping sites at Mt. Baima Nat... This study was designed to introduce a new method of estimating group size and composition of black-andwhite snub-nosed monkeys (Rhinopithecus bieti ) on the basis of faecal amount at sleeping sites at Mt. Baima Nature Reserve. The monkeys spend nights in the form of one-male, multi-female units (OMUs) and all-male units (AMU), and their faecal pellets can be classified into three categories: adult males (the largest), adult females (moderate) and immatures (the smallest) based on their size. Total pellets were counted under sleeping trees used for two nights at Nanren village (99°04′E, 28°34′N, northwest of Yunnan Province, China) in each of four seasons in 2000- 2001. Moreover, data on group composition were collected when the monkeys were passing through an open gully in November 2001. Since the number of adults in OMUs shows a positive significant correlation with the amount of pellets amount in each season, the mean number of feces produced per night per individual is the slope of the regression lines. Thus, group size and composition can be relatively reliably and accurately estimated by the faeces under trees compared with the previous methods of estimation, including the use of monkeys' activities and tracks such as broken branches on steep slopes, in deep gorges and under lower visibility. The use of pellets for population estimates displayed 9.4% deviation in regards to population size of adult females. Some causes of the bias were also discussed. The method might be applicable to other monkey groups of this species if their habitats and main foods are similar to those of the study group. 展开更多
关键词 FECES Group composition Group size Rhinopithecus bieti Sleeping site
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Polygynous Mating System and Behavioural Reason of Black Crested Gibbon (Nomascus concolor jingdongensis) at Dazhaizi,Mt.Wuliang, Yunnan,China 被引量:12
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作者 范朋飞 蒋学龙 +1 位作者 刘长铭 罗文寿 《Zoological Research》 CAS CSCD 北大核心 2006年第2期216-220,共5页
The field research on five black crested gibbon groups, recently performed at Dazhaizi, Mr. Wuliang, Central Yunnan, China, showed that all groups in the local population consisted of one adult male, two adult females... The field research on five black crested gibbon groups, recently performed at Dazhaizi, Mr. Wuliang, Central Yunnan, China, showed that all groups in the local population consisted of one adult male, two adult females and 2 - 5 sub-adults, juveniles and itfants. The mean group size was 6.2 in August 2003 and 6.4 in August 2005. Two subadult males disappeared from their natal home range and three newborns were given birth in Group 3 (G3) and G4 during this study. The two adult females in G1, G2 and G3 gave births and/or carried babies but at different times. There was no aggressive or dominating behaviour observed between the two adult females. One floating female was first seen in G3's territory on April 15, 2005. The two resident females interrupted her duet with adult male and chased her. We did not observe adult male chased this floating female and she left G3's territory 10 days later. Sub-adult males often kept distance with the family, and they often sang solo bouts in their natal territory before they dispersed. The sub-adult males and females dispersed from natal territory and two adult resident females rejected the third one, which might were the reasons why the black gibbon groups were polygyny in Dazhaizi. 展开更多
关键词 Nomascus concolor jingdongensis Group size and composition Social structure Polygyny Local population Wuliang Mountain
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Effects of Composted and Thermally Dried Sewage Sludges on Soil and Soil Humic Acid Properties 被引量:6
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作者 J. M. FERNNDEZ N. SENESI +2 位作者 C. PLAZA G. BRUNETTI A. POLO 《Pedosphere》 SCIE CAS CSCD 2009年第3期281-291,共11页
The effect of annual additions of composted sewage sludge (CS) and thermally dried sewage sludge (TS) at 80 t ha-1 on soil chemical properties was investigated for three years in a field experiment under semiarid cond... The effect of annual additions of composted sewage sludge (CS) and thermally dried sewage sludge (TS) at 80 t ha-1 on soil chemical properties was investigated for three years in a field experiment under semiarid conditions. Humic acids (HAs) isolated by conventional procedures from CS, TS, and unamended (SO) and sludge amended soils were analysed for elemental (C, H, N, S and O) and acidic functional groups (carboxylic and phenolic) and by ultraviolet-visible, Fourier transform infrared and fluorescence spectroscopies. With respect to CS, TS had similar pH and total P and K contents, larger dry matter, total organic C, total N and C/N ratio and smaller ash content and electrical conductivity. Amendment with both CS and TS induced a number of modifications in soil properties, including an increase of pH, electrical conductivity, total organic C, total N, and available P. The CS-HA had greater O, total acidity, carboxyl, and phenolic OH group contents and smaller C and H contents than TS-HA. The CS-HA and TS-HA had larger N and S contents, smaller C, O and acidic functional group contents, and lower aromatic polycondensation and humification degrees than SO-HA. Amended soil-HAs showed C, H, N and S contents larger than SO-HA, suggesting that sludge HAs were partially incorporated into soil HAs. These effects were more evident with increasing number of sludge applications. 展开更多
关键词 elemental composition fluorescence spectroscopy Fourier transform infrared spectroscopy functional group composition
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New Discovery and Zircon Hf Isotopic Composition of the Early Yanshannian Monzogranite in the Yingyangguan Group of Eastern Guangxi, China 被引量:2
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作者 LI Xiang TU Bing +3 位作者 WANG Lingzhan TIAN Yang XIE Guogang ZHANG Jianyu 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1653-1655,共3页
Objective The Yingyangguan Group is widely exposed in the southwestern segment of boundary belt between Yangtze and Cathaysian blocks and is mainly composed of a suit of lower-grade metamorphic marine volcanoclastic-... Objective The Yingyangguan Group is widely exposed in the southwestern segment of boundary belt between Yangtze and Cathaysian blocks and is mainly composed of a suit of lower-grade metamorphic marine volcanoclastic- sedimentary rocks (Zhou Hanwen et al., 2002). Its forming age and petrogenesis are critical for better understanding the orogenic process and relationship of the Yangtze and Cathaysian blocks since the Neoproterozoic. However, few zircon U-Pb ages of samples from the Yingyangguan Group have been reported, which are much debated, such as the metamorphic spilite (819±11 Ma), keratophyre (415.1±2.1 Ma) and ignimbrite (821.3±3.9 Ma) (Tian Yang et al., 2015 and references in). In this study, we focus on the new discovered Early Yanshannian monzogranite and its mafic enclaves from the Yingyangguan Group, and conducted zircon U-Pb dating and in-situ Hf isotopic analyses to constrain their petrogenesis. 展开更多
关键词 Hf ICP MS Pb New Discovery and Zircon Hf Isotopic Composition of the Early Yanshannian Monzogranite in the Yingyangguan Group of Eastern Guangxi China
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Socio-spatial organization reveals paternity and low kinship in the Honduran white bat(Ectophylla alba)in Costa Rica
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作者 Edgar G.GUTIÉRREZ Isabela VIVAS-TORO +5 位作者 Daniela CARMONA-RUÍZ David VILLALOBOS-CHAVES Bernal RODRÍGUEZ-HERRERA Melina Del REAL-MONROY Gloria LEÓN-AVILA Jorge ORTEGA 《Integrative Zoology》 SCIE CSCD 2021年第5期646-658,共13页
Ectophylla alba is a tent-making bat that roosts in mixed-sex clusters comprising adults and offspring.Our goal was to determine the genetic identity of individuals belonging to different roosting groups.We tested the... Ectophylla alba is a tent-making bat that roosts in mixed-sex clusters comprising adults and offspring.Our goal was to determine the genetic identity of individuals belonging to different roosting groups.We tested the hypothesis of kin selection as a major force structuring group composition.We used 9 microsatellites designed for E.alba to determine the genetic identity and probability of parentage of individuals.We analyzed parentage and kinship using the software ML-Relate,GenAIEx,and Cervus.The obtained relationship probabilities(0.5)revealed a clear maternal relationship between female adults and offspring with allele compatibility,and at least 5 relationships between male adults and pups.We found a low degree of relatedness within roosting groups.Between roosting groups at different sites,the mean probability of a half-sibling relationship ranged from 0.214 to 0.244 and,for full-sibling relationship,from 0.383 to 0.553.Genetically,adult individuals were poorly related within clusters,and kinship as an evolutionary force could not explain group membership. 展开更多
关键词 Ectophylla alba group composition KINSHIP microsatellites relatedness
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