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Growth and aggregation control of spinel by shear-force-based melting modification of stainless steel slag

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International Journal of Minerals,Metallurgy and Materials 2018年第10期25卷 1140-1147页

作者： qing Zhao Cheng-jun Liu Tian-ci gao Long-hu Cao Mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic Minerals (Ministry of Education) Northeastern University School of Metallurgy Northeastern University

To improve the efficiency of melting modification for stainless steel(SS) slag, a shear force was introduced in this work and its effects on the spinel and silicate melt were experimentally investigated. The results indicated that the use of shear force changed the nucleation and growth behaviors of spinel and that the effects of shear force varied with its intensity. The aggregation behavior of spinel under different shear-force conditions was studied, revealing that large spinel clusters could be formed when the stirring speed was controlled. However, no notable change in the melt structure of the silicate was detected in this study. The optimal stirring speed for the melting modification treatment was 50 r·min^(-1), which substantially promoted spinel growth and aggregation, resulting in modified SS slag with excellent chromium sequestration capability.

关键词： stainless steel slag spinel crystal growth melting modification shear force chromium sequestration

Synthesis of Biphasic Defective TiO2-x/Reduced Graphene Oxide Nanocomposites with Highly Enhanced Photocatalytic Activity

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Chemical Research in Chinese Universities 2018年第2期34卷 158-163页

作者： gao Guiqi ZHU qing CHONG Hanbao ZHENG jun FAN Congmin LI Guang Center of Modern Experimental Technology Anhui University Hefei 230601 F. R. China School of Physics and Material Science Anhui University Hefei 230601 R R. China College of Materials and Chemistry & Chemical Engineering Chengdu University of Technology Chengdu 610059 P. R. China

Biphasic defective TiO2-x/reduced graphene oxide（RGO） nanocomposites were synthesized by simple hydrothermal reactions. Compared with TiO2-x and commercial P25, TiO2-x/RGO shows much better photocatalytic activity and excellent stability in pollutants degradation, which could be ascribed to Ti^3＋ centers complexed with RGO and the synergetic effect between the two phases. The study reveals a new route for the synthesis of mixed-phase defective TiO2-x/carbon material nanocomposites for photocatalytic applications.

关键词： Defective biphasic TiO2-x Graphene sheet Photocatalysis Reduced graphene oxide

Catalytic Conversion of CO2 to Cyclic Carbonates through Multifunctional Zinc-Modified ZSM-5 Zeolitet

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Chinese Journal of Chemistry 2018年第3期36卷 187-193页

作者： qing-Ning Zhao qing-Wen Song Ping Liu Qian-Xia Zhang jun-Hua gao Kan Zhang State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China Department of Chemistry Shanghai University Shanghai 200444 China

The production of fine chemicals using CO2 as C1 building block through inexpensive heterogeneous catalysts with high efficiency under low pressure is challenging. Herein we propose for the first time the utilization of a multifunctional heterogeneous zinc-modified HZSM-5 （ZnHZSM-5） catalyst for upgrading CO2 by incorporation into cyclic carbonates from CO2 and epoxides. Owing to the nice surface properties such as abundant Lewis acid, Bronsted acid and Lewis base sites, large surface area, and plenty of micropores, CO2 could be concentrated and well activated in ZnHZSM-5 verified by CO2-TPD, TG-MS, etc. Meanwhile, the epoxides were also activated through metal center and hydrogen bond. Therefore, the reaction can easily assemble at the catalyst interface and show exceptional performance, affording the aimed products with high yield of up to 99% in the presence of commercial tetra-n-propylammonium bromide （90% in kilogram scale with 0.004 mol% ZnHZSM-S and 0.03.5 mol% n^Pr4NBr）.

关键词： carbon dioxide utilization zeolite heterogeneous catalysis multifunctional activation heterocycle

Reproductive Ecology of Rhynchanthus beesianus W. W. Smith （Zingiberaceae）in South Yunnan, China： A Ginger with Bird Pollination Syndrome

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Journal of Integrative Plant Biology 2006年第11期48卷 1294-1299页

作者： Jiang-Yun gao Zi-Hui Yang Pan-Yu Ren qing-jun Li Xishuangbanna Tropical Botanical Garden the Chinese Academy of Sciences Mengla Yunnan 666303 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Rhynchanthus beesianus W. W. Smith （Zlnglberaceae） Is an eplphytlc tropical ginger with a very conspicuous floral display, but almost no fruit set under field conditions. The reproductive ecology encompassing phenology, floral biology, and pollination and breeding systems was Investigated In an evergreen broadleaved forest In Yunnan Province, Southwest China. The flowers possess a typical bird pollination syndrome, but no effective pollinators were observed during 138 h of observation. Female Black-breasted Sunbird （Aethopyga saturata） and bumblebees visited R. beesianus regularly, but they all played roles as nectar robbers. No fruit was found In the bagging treatment, and fruit set following manual self-pollination （（57.55 ± 4.08）%） was comparable with cross-pollination （（64.32 ± 4.42）%）, suggesting that R. beeslanus is self-compatible but spontaneous self-pollination In this species does not occur. Seed set of open-pollination （（26.42 ± 3.11）%） was significantly lower than manual self-pollination （（73.41± 4.16）%） and cross-pollination （（75.56 ± 4.52）%）, confirming that R. beeslanus was dependent on animals for fertilization and suffered a serious pollinator-limitation.

关键词： breeding system floral biology pollinator-limitation Rhynchanthus beesianus Zingiberaceae

Influence on Cellular Signal Transduction Pathway in Dairy Cow Mammary Gland Epithelial Cells by Galactopoietic Compound Isolated from Vaccariae segetalis

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Agricultural Sciences in China 2011年第4期10卷 619-630页

作者： WAN Zhong-ying TONG Hui-li LI qing-zhang gao Xue-jun Key Laboratory of Dairy Science Ministry of Education~Northeast Agricultural University Harbin 150030 P.R.China

The galactopoietic mechanism of Vaccaria segetalis is still unknown. Understanding dibutyl phthalate （DBP） separated from Vaccaria segetalis on the expression of lactation signal transduction genes of mammary gland epithelial cells, including prlr, erα, akt1, socs2, pparγ and elf5, will be helpful to reveal the molecular mechanism. Western blot and qRT- PCR were used to study the change of prlr, erα, akt, socs2, pparγ, and elf5 expression at mRNA and protein level. Co- localization expression of prolactin receptor （PRLR） and estrogen receptor α （ERα） was observed by immunofluorescence; the expression changes of miRNAs （21, 125b, 143, and 195） and the secretion of β-casein and lactose were detected by qRT-PCR and RP-HPLC. The results showed that Vaccaria segetalis active compound had similar fuctions as estrogen and/or prolactin （PRL） in dairy cow mammary gland epithelial cells （DCMECs）, increased the expressions of prlr, erα, akt1, and elf5 genes, while repressed pparγ expressions. DBP promoted socs2 mRNA expression, but its protein expressions were repressed. Furthermore, both DBP and PRL could repress the expressions of miRNA-125b, miRNA-143 and miRNA- 195 in DCMECs. DBP could repress the expression of miRNA-21, while the influence of PRL on miRNA-21 was not certain. DBP could promote the lactation ability of DCMECs by regulating the ER and PRLR cellular signal transduction pathway.

关键词： Vaccaria segetalis DBP dairy cow mammary gland epithelial cells signal transduction miRNAs

Influence of austempering process on microstructures and mechanical properties of V-containing alloyed ductile iron

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Journal of Iron and Steel Research International 2018年第1期25卷 81-89页

作者： jun-jun Cui Li-qing Chen State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China College of Mechanical and Vehicle Engineering ShenyangInstitute of Technology Fushun 113122 Liaoning China

The influence of austempering time and vanadium addition on microstructure and mechanical properties of the alloyed ductile iron has been investigated. The 0.30 wt% V-containing and V-free alloyed ductile irons were firstly austenitized at 850 ℃ for 1 h and then austempered in a salt bath at 300 ℃ for 2, 3 and 4 h, respectively. For the 0.3 wt% V-containing alloyed ductile iron, the transformation product （ausferrite） was finer, and a small amount of martensite and a large amount of stable austenite were obtained after austempering for 2 h, while higher hardness and compressive strength of 62.8 HRC and 3000 MPa were achieved. For the V-free alloyed ductile iron, lower hardness and compressive strength were measured to be 56.8 HRC and 2320 MPa. As the austempering time increases, the amount of stable austenite decreases in the V-containing ductile iron, typically for the start of the second stage formation （retained austenite （γτ） →α ＋ carbide）. Based on this, it is assumed that the optimal processing window （OPW） was narrowed due to the addition of 0.30 wt% V as compared to the V-free ductile iron. When the hardness of 0.30 wt% V-alloyed ductile iron was higher than 59 HRC, the highest wear resist- ance was obtained. The mechanical cutting plays a dominant role in abrasive wear process.

关键词： Alloyed ductile iron Vanadium Austempering Microstructure Property Wear resistance

Enhanced separation of tetrafluoropropanol from water via carbon nanotubes membranes:insights from molecular dynamics simulations

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Frontiers of Environmental Science & Engineering 2023年第11期17卷 251-262页

作者： qing Li Xiaomeng Wang Ying Liu Zhun Ma Qun Wang Dongmei Xu jun gao Ruirui Wu Hui Sun Xueli gao College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590China SEPCOIII Electric Power Construction Co.Ltd. Qingdao 266100China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) Ocean University of ChinaQingdao 266100China

Fluorinated alcohols exhibit promising prospects in chemical industry because of their special structure and many exciting properties,in which tetrafluoropropanol(TFP)is extensive applied in synthesis of pesticides,dyestuffs,variety of solvents and ***,the presence of TFP in water garners increasing attention globally because of their intrinsic potential to threat ecosystems and human *** nanotubes(CNTs)membranes are burgeoning candidates for TFP-water separation owing to well-endowed extraordinary structural and transport ***,a grand challenge lies in the rational design of CNTs for improving separation ***,molecular dynamics(MD)simulations were performed to investigate the effects of various parameters on the separation of TFP-water mixtures including feed temperature,CNTs pore diameters,and fluorine functionalization *** was found that TFP was pre-selected in CNTs ranging from 9.48 to 18.98Ådue to preferential adsorption and diffusion *** separation factor of 16 was achieved by(7,7)CNTs and the mass fraction of TFP was purified from 75%to 97.51%.Fluorine modified CNTs separated TFP and water by preferentially permeating water due to hydrogen bonding *** results showed that CNTs modified at both the entrance and interior had better separation performance than CNT modified only at one of these *** 100wt%water content in permeate was achieved by(11,11)CNTs modified with fluorine at the entrance and *** findings provide valuable insights for designing potential candidates for fluorinated alcohol-water azeotropic mixtures membrane separation,and promise extensive application aspects for the reclamation of fluorinated alcohol.

关键词： Fluorinated alcohol Carbon nanotube Molecular simulation Fluorine modified

Laws of the Iterated Logarithm for High-Dimensional Wiener Sausage

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Acta Mathematica Sinica,English Series 2011年第8期27卷 1599-1610页

作者： Yan qing WANG Fu qing gao School of Mathematics and Statistics Wuhan University Wuhan 430072 P. R. China

Let {β（s）,s ≥ O} be the standard Brownian motion in R^d with d ≥ 4 and let ｜Wr（t）｜ be the volume of the Wiener sausage associated with {β（s）, s ≥ O} observed until time t. Prom the central limit theorem of Wiener sausage, we know that when d ≥ 4 the limit distribution is normal. In this paper, we study the laws of the iterated logarithm for ｜Wr（t）｜ - e｜Wr（t）｜ in this case.

关键词： Wiener sausage Kolmogorov's law of the iterated logarithm Chung's law of the iterated logarithm

Effect of CXCR4 pretreated with ultrasound-exposed microbubbles on accelerating homing of bone marrow mesenchymal stem cells to ischemic myocardium in AMI rats

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Asian Pacific Journal of Tropical Medicine 2015年第9期8卷 751-756页

作者： jun-Yi Gu Hui-Fen Shi Xiu-Li gao qing-qing Ma Bo Zhang Department of Ultrasound in Medicine East Hospital Tongji University School of Medicine

Objective: To investigate the role and potential mechanism of CXCR4 in promoting targeted homing of bone marrow mesenchymal stem cells(BMSCs) with ultrasound-exposed microbubbles(UM) pretreatment. Methods: Third generation BMSCs were divided into four groups control group, ultrasound(US) group, UM group and ultrasound-exposed microbubbles plus catalase group. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and protein expression, respectively. Third generation BMSCs were labeled with Fluo-α/AM and divided into three groups: control group, US group and UM group, and flurorescence intensities in the cells were observed immediately, 5 min and 15 min after intervention underflurorescence microscope. The calcium iron levels in the cells were analyzed. BMSCs were divided into i ve group: group A without calcium in the medium, group B, group C, group D and group E containing calcium chloride with concentration of l mol, 2 mol, 4mol, anti-calciurn-sensing receptor antibody, respectively. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and proteins expression of the third generation BMSCs of each group, respectively. Results: The levels of CXCR4 m RNA transcription and protein expression between US group and control group had no statistically signii cant dif erence(P>0.05) shown by RT-PCR and western blot; the transcription level in the UM group was signii cantly higher than that in US group and control group(P0.05), which in the cells of UM group was signii cantly higher than that in the cells of both US group and control group(P<0.05). Compared to group A, expressions of CXCR4 of group B to D were signii cantly increased in

关键词： Ultrasound-exposed microbubbles Bone marrow mesenchymal stem cells CXCR4 Calciumion