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1. chinaXiv:202004.00003 [pdf]

A new species of Amynodontopsis (Perissodactyla:?Amynodontidae) from the Middle Eocene of Jiyuan,?Henan, China

WANG Xiao-Yang; WANG Yuan-Qing; ZHANG Rui; ZHANG Zhong-Hui; ?LIU Xiao-Ling; REN Li-Ping
Subjects: Biology >> Zoology

An adult amynodont skull, collected from the Middle Eocene Niezhuang Formation of Jiyuan Basin (Henan, China), is recognized as a new species Amynodontopsis jiyuanensis sp. nov. The specimen possesses the typical features of the genus Amynodontopsis, such as a dolichocephalic skull with elevated roof, premaxilla-nasal contact, large preorbital fossa extending posteriorly medial to the orbit, inner surface of anterior orbital bar concave in continuation with the preorbital fossa, antecrochet usually presented on M1, and metastyle of M3 strongly deflected labially. A. jiyuanensis is diagnosed by a combination of the following characters: long nasals, nasal process of premaxilla extending far back laterally below the nasal and excluding the maxilla from the border of external nares, nasal notch above the post-canine diastema, more transverse and proportionally longer protoloph and metaloph on upper molars. Comparison with known species of Amynodontopsis indicates that it is the most primitive one in the genus, due to the possession of primitive characters. Associated fossil mammals support a correlation of the strata bearing A. jiyuanensis with the Shara Murun Formation of the Erlian Basin, Nei Mongol, China, namely the Middle Eocene Sharamurunian Asian Land Mammal Age (ALMA), prior to all other known Amynodontopsis species. The earlier geologic age and primitive morphological features of A. jiyuanensis suggest that Amynodontopsis has an Asian origin in the Middle Eocene and later immigrated into North America.

submitted time 2020-03-31 From cooperative journals:《古脊椎动物学报》 Hits6442Downloads1175 Comment 0

2. chinaXiv:201910.00048 [pdf]

Monitoring the impact of climate change and human activities on grassland vegetation dynamics in the northeastern Qinghai-Tibet Plateau of China during 2000–2015

XIONG Qinli ; XIAO Yang; Marwa Waseem A HALMY ; Mohammed A DAKHIL; LIANG Pinghan; LIU Chenggang; ZHANG Lin; Bikram PANDEY; PAN Kaiwen; Sameh B EL KAFRAWAY; CHEN Jun
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology

Climate change and human activities can influence vegetation net primary productivity (NPP), a key component of natural ecosystems. The Qinghai-Tibet Plateau of China, in spite of its significant natural and cultural values, is one of the most susceptible regions to climate change and human disturbances in the world. To assess the impact of climate change and human activities on vegetation dynamics in the grassland ecosystems of the northeastern Qinghai-Tibet Plateau, we applied a time-series trend analysis to normalized difference vegetation index (NDVI) datasets from 2000 to 2015 and compared these spatiotemporal variations with trends in climatic variables over the same time period. The constrained ordination approach (redundancy analysis) was used to determine which climatic variables or human-related factors mostly in?uenced the variation of NDVI. Furthermore, in order to determine whether current conservation measures and programs are effective in ecological protection and reconstruction, we divided the northeastern Qinghai-Tibet Plateau into two parts: the Three-River Headwater conservation area (TRH zone) in the south and the non-conservation area (NTRH zone) in the north. The results indicated an overall (73.32%) increasing trend of vegetation NPP in grasslands throughout the study area. During the period 2000–2015, NDVI in the TRH and NTRH zones increased at the rates of 0.0015/a and 0.0020/a, respectively. Specifically, precipitation accounted for 9.2% of the total variation in NDVI, while temperature accounted for 13.4%. In addition, variation in vegetation NPP of grasslands responded not only to long- and short-term changes in climate, as conceptualized in non-equilibrium theory, but also to the impact of human activities and their associated perturbations. The redundancy analysis successfully separated the relative contributions of climate change and human activities, of which village population and agricultural gross domestic product were the two most important contributors to the NDVI changes, explaining 17.8% and 17.1% of the total variation of NDVI (with the total contribution >30.0%), respectively. The total contribution percentages of climate change and human activities to the NDVI variation were 27.5% and 34.9%, respectively, in the northeastern Qinghai-Tibet Plateau. Finally, our study shows that the grassland restoration in the study area was enhanced by protection measures and programs in the TRH zone, which explained 7.6% of the total variation in NDVI.

submitted time 2019-10-26 From cooperative journals:《Journal of Arid Land》 Hits4897Downloads709 Comment 0

3. chinaXiv:201711.00127 [pdf]

Synthesis, Structure and Photoelectric Property of a 3D Supramolecular Zinc Coordination Polymer

LUO Ya-Nan; LIU Zhi-Chen; JIANG Hui-Ying; YU Li-Ying; YU Xiao-Yang
Subjects: Chemistry >> Physical Chemistry

Using a rigid azo ligand 4-[(8-hydroxy-5-quinolinyl)azo]-benzoic acid (H2L), a new supramolecular compound [Zn(L)(H2O)2]n (1) has been solvothermally synthesized and structurally characterized by X-ray single-crystal diffraction, infrared spectrum, elemental analysis, power X-ray diffraction and thermal analysis. Compound 1 crystallizes in monoclinic, space group C2/c with a = 30.372(8), b = 11.415(3), c = 9.248(3) ?, β = 106.94(3)?, V = 3067.20(15) ?3, C16H13N3O5Zn, Mr = 392.66, Z = 8, Dc = 1.701 Mg/m3; F(000) = 1600, μ = 1.636 mm?1, re?ections collected: 7290, re?ections unique: 2735, Rint = 0.0282, R = 0.0351, wR (all data) = 0.0919, GOOF on F2 = 1.036. Compound 1 exhibits a one-dimensional (1D) zig-zag chain structure connected into a three-dimensional (3D) supramolecular network through hydrogen bonding interactions. Fluorescent property and electrochemical property were detected on compound 1.

submitted time 2017-11-05 From cooperative journals:《结构化学》 Hits4055Downloads1902 Comment 0

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