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Photodegradation of 17α-ethynylestradiol in dissolved humic substances solution：Kinetics,mechanism and estrogenicity variation

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Journal of Environmental Sciences 2017年第4期29卷 196-205页

作者： dong ren Bin Huang Dan Xiong Huan He Xiangqi Meng Xuejun Pan Faculty of Environmental Science and Engineering Kunming University of Science and Technology

17α-Ethynylestradiol（EE2） in natural waters may cause adverse effects on organisms due to its high estrogenic potency. Laboratory studies were performed to study the effects of a local humic acid（LHA）, fulvic acid（LFA） and Aldrich humic acid（AHA） on the photochemical behavior and estrogenic potency of EE2. Here photolytic experiments demonstrated that pure aqueous EE2 could undergo direct and self-sensitized photodegradation at a global rate of 0.0068 hr^-*** rate of EE2 in 5.0 mg/L dissolved humic substances（DHS） was determined to be 0.0274, 0.0296 and 0.0254 hr^-1 for LHA, LFA and AHA, respectively. Reactive oxygen species（ROS） and triplet dissolved humic substances（^3DHS＊） scavenging experiments indicated that the promotion effect of DHS on EE2 photodegradation was mainly aroused by the reactions of HOU（35%–50%）,~1O2（〈10%） andDHS＊（22%–34%）. However, the photodegradation of EE2 could also be inhibited when DHS exceeded the threshold of 10 mg/L. Three hydroxylation products of EE2 were identified using GC–MS and their formation pathways were also proposed. In vitro estrogenicity tests showed that EE2 was transformed into chemicals without estrogenic potency. These findings could extend our knowledge on the photochemical behaviors of steroid estrogens in sunlit natural waters.

关键词： 17α-Ethynylestradiol Photodegradation Dissolved humic substances Reactive oxygen species Estrogenic potency

Vanadium Haloperoxidases Model Compounds: Synthesis, Structural Characterization and Mimic Catalytic Bromination Activity of [VO(C_2O_4)(2,2′-bipy)(H_2O)]·C_2H_5OH and VO(C_2O_4)(phen)(H_2O)

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Chemical Research in Chinese Universities 2012年第5期28卷 768-774页

作者： ren dong-xue CAO Yun-zhu CHEN Chen XING Yong-heng College of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 116029R R.China

Two oxo-vanadium（IV） complexes, [VO（C2O4）（2,2′-bipy）（H2O）]·C2H5OH（1） and VO（C2O4）（phen）（H2O）（2）, where 2,2′-bipy=2,2′-bipyridyl, phen=1,10-phenanthroline, were synthesized as potential functional models of vanadium haloperoxidases（VHPOs） in mixed solvent of ethanol and water at room temperature. The complexes were characterized by elemental analysis, infrared（IR）, UV-Vis and X-ray crystallography. Structural analyses showed that vanadium atom was coordinated by a terminal oxygen, one oxygen atom from coordinated water, two oxygen atoms from the carboxylate group of oxalic acid, and two nitrogen atoms（N1 and N2） from 2,2′-bipy/phen. Central vanadium atoms in complexes 1 and 2 were both in a distorted-octahedral environment, and some intermolecular hydrogen bonding linkages were also observed in each complex. Bromination reaction activity of the two complexes was evaluated with phenol red as organic substrate in the presence of H2O2, Br-and phosphate buffer, indicating that they can be considered as a potential functional model of VHPO. In addition, thermal analysis was also performed and discussed in detail.

关键词： Oxo-vanadium complex Bromination reaction activity Vanadium haloperoxidase

Constitutive modeling and analysis on high-temperature flow behavior of 25 steel

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Journal of Iron and Steel Research International 2021年第1期28卷 76-85页

作者： Wei Wei Chao-long Yuan ren-dong Wu Wei Jiao Ding-chuan Liang Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

The constitutive relationship is the basis for studying the material processing technology and controlling the quality of *** and models of the plastic flow behavior of materials are often required during the manufacturing ***,establishing constitutive models with high precision and generalization and enriching material database is of great significance for optimizing processing technology and product quality of the *** on the Gleeble thermal compression test results,the essential relationship of 25 steel between the flow stress and thermal–mechanical state variables,such as temperature,strain rate,and strain,is quantitatively discussed for the first *** with the Zener–Hollomon parameter and considering the influence of strain compensation,the constitutive model of 25 steel is built by the hyperbolic-sine equation over the full strain *** the modeling process,the influence of strain on material constants is characterized by polynomial *** selection basis of polynomial order is discussed in-depth,and the inconsistency between calculation accuracy and fitting effect is ***,the accuracy of the model is analyzed,and the generalization and applicability are *** is proved that the developed model can accurately predict the flow behavior of materials in the full strain range.

关键词： Constitutive relationship Flow behavior Plastic deformation Polynomial fitting Generalization

The larvae of Gnaptorina felicitana and Agnaptoria amdoensis of the tribe Blaptini from China(Coleoptera:Tenebrionidae)

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动物分类学报 2014年第2期39卷 275-282页

作者： Xi-Chao Zhu Guo-dong ren College of Life Sciences of Hebei University Key Laboratory of Invertebrate Systematics and Application of Hebei Province

This paper describes the morphological data of the larvae of two species from the tribe Blaptini Leach, 1815. The two species are Gnaptorina felicitana Reitter and Agnaptoria amdoensis G. Medvedev, whose larvae have not been reported up to now. In this paper, morphological characters, informations of specimen, and character figures of the two species＇ larvae are provided. A key to the two genera and the reported species is listed here. The larvae specimens are deposited in the Museum of Hebei University.

关键词： Coleoptera Tenebrionidae Blaptini larva.

A New Species of the Family Juraperlidae (Insecta:Grylloblattida) from the Middle Jurassic of China

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 710-713页

作者： CUI Yingying Olivier BETHOUX SHIH Chungkun ren dong College of Life Science Capital Normal University Beijing 100048 China 216 Cours de la Liberation 38100 Grenoble France

Juraperla grandis sp. nov. （Grylloblattida： Juraperlidae） is described from the Daohugou locality （Middle Jurassic, China）. Its wing venation is very similar to that ofJuraperla daohugouensis Huang and Nd, 2007 （Grylloblattida： Juraperlidae）, in the particular occurrence of a supplementary longitudinal vein in the area between the anterior wing margin and ScP. The larger size of the new specimen, the lower number of CuA1 branches, and the occurrence of two rows of cells between MP and CuA in forewings justify the erection of a new species, J. grandis sp. nov.. The material also preserved hind wing and body structures, described for the first time in Juraperlidae.

关键词： fossil insect Juraperlidae Grylloblattida new taxon Jurassic Inner Mongolia

Research and development of 780 MPa cold rolling TRIP-aided steel

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 399-406页

作者： Qiang Liu Di Tang Hai-tao Jiang ren-dong Liu Xiao-yong Tang National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China Researchand Development Center Anshan Iron and Steel （Group） Corp. Anshan 114001 Liaoning China

As an industry-university cooperative project, an experimental research was conducted to develop a new cold-rolled transformation-induced plasticity （TRIP） steel with a tensile strength of 780 MPa and an elongation of 25% under the conditions that some processing parameters were preestablished according to the actual conditions of factory production lines. The optimal heat treatment conditions for obtaining excellent strength-ductility balance, specifically in intercritical annealing temperature and isothermal treatment temperature, were investigated by means of thermal simulation tests. Ultimately the desirable mechanical properties were attained successfully, and the microstructure and retained austenite stability were studied by optical microscopy （OM） and electron back-scattered diffraction （EBSD）. It has been discovered that the sizes of retained austenite grains are generally proportional to the sizes of carbon-clear space （ferrite and bainite） around them, and there is marked selectivity in their transition sequences under stress-strain.

关键词： TRIP steel heat treatment retained austenite stability

Effect of welding speed on microstructure and mechanical properties of laser-welded transformation induced plasticity(TRIP)steels

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Journal of Iron and Steel Research International 2020年第9期27卷 1087-1098页

作者： Tao Wang Mei Zhang ren-dong Liu Liang Zhang Lin Lu Wen-heng Wu Shanghai Research Institute of Materials Shanghai Engineering Research Center of 3D Printing MaterialsShanghai 200437China School of Materials Science and Engineering Shanghai UniversityShanghai 200072China State Key Laboratory of Advanced Special Steels Shanghai UniversityShanghai 200072China Technique Center of Ansteel Ansteel Group CorporationAnshan 114001LiaoningChina

The weldability of 0.28C-2.0Mn-0.93Al-0.97Si(wt.%)transformation induced plasticity(TRIP)steels was investigated using a 2.5 kW CO2 laser at the welding speeds of 2,2.5 and 3 m/*** welded joints were characterized in terms of hardness,tensile properties and ***-quality welded joints of TRIP steels with the carbon equivalent of 0.7 were *** loss of ductility,nearly unvaried hardness of the fusion zone(FZ)and tensile strength equal to the base metal were observed with increasing welding *** martensite and lower bainite formed in FZ and the microstructure of FZ varied little with welding *** thermal simulations of heat-afected zone(HAZ)were carried out using a quenching dilatometer,and the microstructures of dilatometric samples revealed the carbon diffusion-controlled transformations in *** microstructure distribution of HAZ could be influenced by the welding speed due to the significant temperature gradient over the narrow HAZ.

关键词： Laser welding Welding speed Transformation induced plasticity steel Tensile property Weld thermal simulation Microstructural evolution

Swarming caddisflies in the mid-Cretaceous

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National Science Review 2024年第8期11卷 125-135页

作者： Jiajia Wang Michael S.Engel Weiting Zhang Chungkun Shih Rui Qiu dong ren College of Life Sciences Capital Normal University Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Division of Invertebrate Zoology American Museum of Natural History Facultad de Ciencias Biológicas Universidad Nacional Mayor de San Marcos Departamento de Entomología Museo de Historia NaturalUniversidad Nacional Mayor de San Marcos Hebei International Joint Research Center for Paleoanthropology Hebei GEO University Department of Paleobiology National Museum of Natural History Smithsonian Institution National Natural History Museum of China

Swarming,as a special form of mating aggregation,is most noteworthy in insects of the orders Ephemeroptera,Diptera,and *** in extant trichopterans is well understood in terms of sex composition,specific mating behaviors,and functional morphological specializations of adults,but an exploration of the evolution of such aggregative behaviors is hampered by the dearth of available examples from the fossil record as well as the ability to reliably distinguish the few gatherings as the result of swarming relative to other taphonomic or behavioral *** we describe five new fossil species of caddisflies preserved in mid-Cretaceous amber from Myanmar,all preserved as large *** aggregations of these five new species can be positively identified as swarms based on morphological traits of wing shape,as well as the presence of particular forms of sexual *** of a phylogenetic reconstruction of both molecular and morphological data as well as ancestral-trait reconstructions and tip-dating analyses indicate that swarming was likely present in the Triassic as a feature of the trichopteran *** most Mesozoic insectivorous predators were diurnal based on morphological evidence,largely nocturnal caddisflies would have been freed from such *** phylogeny also shows a correlation between the rise of nocturnal bat predators from the Paleocene or early Eocene and the repeated loss of swarming from various clades of caddisflies,revealing the potential impact of bat predation on reshaping the behavioral landscape of Trichoptera during the Cenozoic.

关键词： swarming caddisflies Cretaceous ancestral-trait reconstructions

Notch pathway inhibitor DAPT enhances Atoh1 activity to generate new hair cells in situ in rat cochleae

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Neural Regeneration Research 2017年第12期12卷 2092-2099页

作者： Wen-wei Luo Zhao Han dong-dong ren Xin-wei Wang Fang-lu Chi Juan-mei Yang Department of Otolaryngology Eye & ENT Hospital of Fudan University Research Institute of Otolaryngology Fudan University

Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regeneration. The sensory region of rat cochlea is difficult to transfect, thus new hair cells are rarely produced in situ in rat cochlear explants. After culturing rat cochleae in medium containing 10% fetal bovine serum, adenovirus successfully infected the sensory region as the width of the supporting cell area was significantly increased. Adenovirus encoding Atoh1 infected the sensory region and induced hair cell formation in situ. Combined application of the Notch inhibitor DAPT and Atoh1 increased the Atoh1 expression level and decreased hes1 and hes5 levels, further promoting hair cell generation. Our results demonstrate that DAPT enhances Atoh1 activity to promote hair cell regeneration in rat cochlear sensory epithelium in vitro.

关键词： nerve regeneration Atoh 1 DAPT. transdifferentiation gamma secretase inhibitor cochlea sensory epithelium fetal bovine serum hair cell supporting cell hair cell regeneration neural regeneration