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Cleavage of catalytic ally grown carbon nanofibers into hydrophilic segments by oxidation in a mixture of concentrated HNO3-H2SO4 in an autoclave

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Journal of Coal Science & Engineering(China) 2012年第2期18卷 188-190页

作者： TENG Li-hua WANG zhi-jiang TANG Tian-di School of Biology and Environmental Science Zhejiang Wanli UniversityNingbo 315100China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035China

The catalytically grown carbon nanofibers were treated by a mixture of concentrated nitric aid and sulfuric aid in an autoclave at temperature 333, 363 and 423 K. It was found that the samples treated at 363 K and 423 K were still well dispersed in water 15 hours later, indicating that carbon nanofibers can be made hydrophilicy. It was also found that the dispersion was destroyed when the pH value was lowered by adding acid. The results are significant when the carbon nanofibers are used as enhancing component in polymer composite material because several hundreds of nm are perfect size and the hydrophilicity controls the dispersion of CNFs in the polymer media. It is concluded that the amount of the oxygen-containing groups on the surface and the hydrophilicity of the carbon nanofibers can be controlled by the treatment temperature, and that the carbon nanofibers can be cleaved into uniform segments.

关键词： catalytically grown carbon nanofibers carbon nanotubes oxidation

Why was Pakistan extreme precipitation stronger in 2022 than in 2010?

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Advances in Climate Change Research 2023年第6期14卷 913-920页

作者： Xu YUAN Kun YANG Jing SUN Yan WANG Yan-Yi HE Mi-Jun ZOU Yao-zhi jiang Polar and Marine Research Institute College of Harbor and Coastal EngineeringJimei UniversityXiamen 361021China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084China National Tibetan Plateau Data Center State Key Laboratory of Tibetan Plateau Earth SystemResource and EnvironmentChinese Academy of SciencesBeijing 100101China Institue of Geographic Science and Natural Resources Research Chinese Academy of Sciences Beijing 100101China School of Environmental and Geographical Science Shanghai Normal UniversityShanghai 200234China Yangtze River Delta National Observatory of Wetland Ecosystem Shanghai Normal UniversityShanghai 200234China

In Pakistan,five continuous extreme precipitation events in the summer(July-August)of 2022 caused disastrous floods,depriving thousands of people's lives and ruining millions of *** tremendous disaster in Pakistan also happened in 2010 but with three concentrated extreme precipitation events in the middle of *** amount of Pakistan heavy daily precipitation in 2022 surpasses that in 2010 record,making it the strongest precipitation event ever *** comprehensively understand the causes of extreme precipitation in Pakistan,this study investigated the anomalies in atmospheric circulation and moisture contribution of 2010/2022 extreme precipitation and compared their *** results show that an atmospheric blocking over northern Europe in both 2022 and 2010 enhanced convection in Pakistan by transporting cold-dry air from the high-latitude region and benefiting warm-wet monsoonal air marching to *** employing a moisture track model,the main moisture sources for summer precipitation in Pakistan were *** is found that moisture contributions except from Eurasia were enhanced,causing extreme *** particular,enhanced moisture contribution from the southern Indian Ocean and the northern Indian continent in 2022 are more prominent than that in *** increased moisture contribution in 2010 was due to increased evaporation induced by warming sea surface in the Indian Ocean,while much richer moisture transport in 2022 was attributed to the enhanced cross-equatorial flow induced by the anomalous subtropical high in the Southern ***,attention should be paid to the role of subtropical high in the Southern Hemisphere in addition to those in Northern Hemisphere in understanding disastrous extreme precipitation events inPakistan.

关键词： Extreme precipitation Moisture transport Moisture sources Pakistan

Trans-acting factors from the human fetal liver bindingto the human ε-globin gene silencer

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Cell Research 1997年第2期7卷 151-159页

作者： YAN zhi jiang CHU jiang RUO LAN QIAN(Shanghai Institute of Cell Biology, Chinese Academy ofSciences, Shanghai 200031, China) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai China

The developmental stage-specific silencing of the human ε-globin gene during embryonic life is controlled, inpart, by the silencer (-392bp～-177bp) upstream of thisgene. In order to elucidate its role, the nuclear extractfrom the human fetal liver has been prepared and the interactions between trans-acting factors and this silencerelement have been examined. By using DNasel footprinting assay, a major protected region from -278bp to -235bpwithin this silencer element was identified. Furthermore,we found in gel mobility shift assay and Southwestern blotting assay that there were at least four trans-acting factors (MW ≈ 32, 28, 26 and 22kD) in the nuclear extractisolated from the human fetal liver, which could specifically bind to this region. Our results suggested that thesetrans-acting factors might play an important role in silencing the human embryonic ε-globin gene expression at thefetal stage through the interactions with this silencer.

关键词： Human ε-globin gene silencer transacting factor

Columnar to Equiaxed Transition During Solidification of Small Ingot by Using Electric Current Pulse

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Journal of Iron and Steel Research International 2009年第6期16卷 7-12页

作者： LI Jie MA Jian-hong SONG Chang-jiang LI zhi-jun GAO Yu-lai ZHAI Qi-jie Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University Shanghai 200072 China

A new approach to applying the electric current pulse （ECP） with parallel electrodes to the promotion of the transition from columnar crystal to equiaxed crystal and the improvement of macrosegregation was introduced. The ECP was applied to different stages of the solidification. The results showed that the application of the ECP in both the initial stage （the thickness of solidified shell reached 2 mm approximately） and the late stage （the thickness of solidified shell reached 14 mm approximately） of solidification can promote the columnar to equiaxed transition （CET）. The analysis showed that during solidification, a large number of nuclei around the upper surface fell off due to ECP, which subsequently showered on the melt and impinged the growth front of the columnar crystal. Therefore, the CEToccurred. In addition, this method was also employed to influence the solidification process of bearing steel, and the results showed that the structure was changed from columnar crystal to equiaxed crystal, indicating that ECP can enhance the homogeneity of structure and composition of bearing steel.

关键词： columnar to equiaxed transition solidification electric current pulse macrosegregation

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Purification and Characterization of a Novel Tetradecapeptide from Ginseng Polypeptides with Enhancing Memory Activity for Mice

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Chemical Research in Chinese Universities 2013年第4期29卷 638-641页

作者： LUO Hao-ming jiang Rui-zhi YANG Xiao-hong CHEN Ying-hong HONG Tie WANG Ying School of Pharmaceutical Sciences Jilin University Changchun 130021 P R. China Jilin Academy of Chinese Medicine and Material Medical Science Changchun 130012 P. R. China

Aiming at isolating and investigating the active ingredients of the aqueous extract from Panax ginseng which showed enhancing memory activity, the authors characterized one ingredient. To separate the oligosaecharides and polypeptides, a DEAE-Sephadex A-50 colum was used. The enhanced memory activity in mice was studied by Mirros water maze tesk in mice. The dose of oligosacchrides, polypeptides or Piracetam was 30 mg/kg per day with intraperitoneal administration. The oligosaccharides did not show enhancing memory effect, but polypeptides did show. This result demonstrates that the active ingredients of the aqueous extract from Panax ginseng which showed enhancing memory effect was polypeptides. The purification of the polypeptides was performed on a Sephadex G-25 column. A novel tetradeeapeptide was purified from the polypeptides and its structure was determined by liquid chromatography-eleetrospray ionization-quadrupole-time of flight-mass spectrometry（LC-ESI-Q-TOF-MS） with the amino acid sequence of Lys-Ser-Leu-Thr-Leu-Thr-Ser-Ser-Leu-Ser-Tyr-Thr-Asp-Ser.

关键词： Panax ginseng Polypeptide Tetradecapeptide Enhanced memory activity Liquid chromatography-tandemmass spectrometry(LC-MS/MS)

In situ study of calcite-Ⅲ dimorphism using dynamic diamond anvil cell

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Chinese Physics B 2022年第9期31卷 421-427页

作者： Xia Zhao Sheng-Hua Mei zhi Zheng Yue Gao jiang-zhi Chen Yue-Gao Liu Jian-Guo Sun Yan Li Jian-Hui Sun CAS Key Laboratory for Experimental Study under Deep-sea Extreme Conditions Institute of Deep-sea Science and EngineeringChinese Academy of Sciences(CAS)Sanya 572000China University of Chinese Academy of Sciences Beijing 100049China Department of Mechanical Engineering National University of Singapore(NUS)Singapore 117575Singapore

The phase transitions among the high-pressure polymorphic forms of CaCO_(3)(cc-Ⅰ,cc-Ⅱ,cc-Ⅲ,and cc-Ⅲb)are investigated by dynamic diamond anvil cell(dDAC)and in situ Raman *** are carried out at room temperature and high pressures up to 12.8 GPa with the pressurizing rate varying from 0.006 GPa/s to 0.056 GPa/*** situ observation shows that with the increase of pressure,calcite transforms from cc-Ⅰto cc-Ⅱat~1.5 GPa and from cc-Ⅱto cc-Ⅲat~2.5 GPa,and transitions are independent of the pressurizing ***,as the pressure continues to increase,the cc-Ⅲb begins to appear and coexists with cc-Ⅲwithin a pressure range that is inversely proportional to the pressurizing *** the pressurizing rates of 0.006,0.012,0.021,and 0.056 GPa/s,the coexistence pressure ranges of cc-Ⅲand cc-Ⅲb are 2.8 GPa-9.8 GPa,3.1 GPa-6.9 GPa,2.7 GPa-6.0 GPa,and 2.8 GPa-4.5 GPa,*** dependence of the coexistence on the pressurizing rate may result from the influence of pressurizing rate on the activation process of transition by reducing the energy *** higher the pressurizing rate,the lower the energy barrier is,and the easier it is to pull the system out of the coexistence *** results of this in situ study provide new insights into the understanding of the phase transition of calcite.

关键词： calcite-Ⅲ dimorphism dynamic diamond anvil cell in situ Raman spectroscopy pressurizing rate

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Karyomorphology of three species in Dipentodon(Dipentodontaceae),Perrottetia(Celastraceae),and Tapiscia(Tapisciaceae) of the order Huerteales and their phylogenetic implications

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Journal of Systematics and Evolution 2009年第4期47卷 291-296页

作者： Jing YANG jiang-Chong WU zhi-Jian GU~* (Kunming Botanical Garden,Kunming Institute of Botany,Chinese Academy of Sciences,Kunming 650204,China) (Kunming Botanical Garden Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

The karyomorphology of three species in Dipentodon(Dipentodontaceae),Perrottetia(Celastraceae),and Tapiscia(Tapisciaceae),namely Dipentodon sinicus,Perrottetia racemosa,and Tapiscia sinensis,was investigated in the present *** molecular research has discovered close relationships among these three genera, which has led to the establishment of the order Huerteales with Perrottetia being placed in Dipentodontaceae. Herein we report the chromosome numbers of *** and P racemosa for the first time,and present their karyotype formulas as 2n = 34 = 22 sm+12 st(***),2n = 20 = 11 m+9 sm(***),and 2n = 30 = 22 m(2SAT)+8sm(***).Asymmetry of their karyotypes is categorized to be Type 3B in ***,Type 2A in ***,and Type 2A in *** of the species shows special cytological features. Compared with Perrottetia,Dipentodon has a different basic chromosome number,a higher karyotype asymmetry, and different karyomorphology of its interphase nuclei,mitotic prophase,and ***,on the basis of these results,we have reservations regarding the suggestion of placing Dipentodon and Perrottetia together in the family Dipentodontaceae.

关键词： chromosome number Dipentodon karyomorphology Perrottetia phylogenetic relationship Tapiscia.

Effects of Chinese herbal medicine Xiangbin prescription on gastrointestinal motility

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World Journal of Gastroenterology 2017年第16期23卷 2987-2994页

作者： zhi jiang Li-Xing Cao Bo Liu Qi-Cheng Chen Wen-Fan Shang Lu Zhou Dan-Yan Li De-An Guo zhi-Qiang Chen Second Affiliated Hospital of Guangzhou University of Chinese Medicine Guangzhou 510120Guangdong ProvinceChina Institute of Basic Medical Sciences Chinese Academy of Medical SciencesBeijing 100005China Shanghai Research Center for Modernization of Traditional Chinese Medicine Shanghai Institute of Materia MedicaShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 201203China

AIM To investigate the effects of Xiangbin prescription(XBP), a Chinese herbal concoction, on gastrointestinal *** Forty healthy volunteers were recruited for this randomized controlled trial of XBP. Antroduodenojejunal manometry was used to monitor gastrointestinal motility in these subjects. After the subjects had fasted for at least 12 h, XBP(n = 30) or placebo(n = 10) was orally administrated and gastrointestinal motility was recorded for 4 h. Plasma motilin and ghrelin were measured by enzyme-linked immunosorbent *** Oral administration of XBP significantly increased the amplitude of duodenal contractions [19.5(13.0-26.7) vs 16.9(12.3-23.9), P < 0.05], jejunal contractions [18.3(15.3-25.0) vs 15.4(11.7-23.9), P < 0.01], and the motility index of duodenal contractions [522.0(146.0-139.0) vs 281.0(76.5-1006.0), P < 0.01] in phase Ⅱ of the migratory motor complex(MMC), which subsequently initiated the MMC cycle [74.0(30.0-118.0) vs 116.5(24.0-219.0), P < 0.05], shortened the duration of phase I of the MMC [42.0(0.0-90.0) vs 111.5(42.0-171.0), P < 0.01], and lengthened the duration of phase Ⅱ of the MMC [120(21-240) vs 58(16-170), P < 0.01] compared to the duration before XBP administration. There were significant differences in the amplitude of jejunal contractions [19.8(14.0-30.0) vs 18.0(13.0-28.5), P < 0.05], the motility index of duodenal contractions [236.0(115.0-306.0) vs 195.0(109.0-310.0), P < 0.05], and jejunal contractions [214.0(95.0-403.0) vs 178.0(55.0-304.0), P < 0.01] in phase Ⅲ of the MMC. Oral administration of XBP greatly increased plasma motilin(57.69 ± 9.03 vs 49.38 ± 8.63, P < 0.01) and ghrelin(279.20 ± 104.31 vs 238.73 ± 115.59, P < 0.01) concentrations compared to concentrations after oral administration of the *** XBP can stimulate duodenal and jejunal motility and increase the concentrations of plasma motilin and ghrelin. The clinical applicability of XBP in treating GDIM deserves investigation.

关键词： Antrotroduodenojejunal manometry Gastrointestinal motility Migrating motor complex Xiangbin concoction Motilin Ghrelin

The integrative analysis of microRNA and mRNA expression in Apis mellifera following maze-based visual pattern learning

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Insect Science 2014年第5期21卷 619-636页

作者： Qiu-Hong Qin Zi-Long Wang Liu-Qing Tian Hai-Yan Gan Shao-Wu Zhang zhi-jiang Zeng Honeybee Research Institute Jiangxi Agricultural University Nanchang China ARC Center of Excellence in Vision Science Research School of Biology The Australian National University Canberra ACT Australia

The honeybee （Apis mellifera） is a social insect with strong sensory capacity and diverse behavioral repertoire and is recognized as a good model organism for studying the neurobiological basis of learning and memory. In this study, we analyzed the changes in microRNA （miRNA） and messenger RNA （mRNA） following maze-based visual learning using next-generation small RNA sequencing and Solexa/lllumina Digital Gene Expression tag profiling （DGE）. For small RNA sequencing, we obtained 13 367 770 and 13 132 655 clean tags from the maze and control groups, respectively. A total of 40 differentially expressed known miRNAs were detected between these two samples, and all of them were up-regulated in the maze group compared to the control group. For DGE, 5 681 320 and 5 939 855 clean tags were detected from the maze and control groups, respectively. There were a total of 388 differentially expressed genes between these two samples, with 45 genes up-regulated and 343 genes down-regulated in the maze group, compared to the control group. Additionally, the expression levels of 10 differentially expressed genes were confirmed by quantitative reverse transcription polymerase chain reaction （qRT-PCR） and the expression trends of eight of them were consistent with the DGE result, although the degree of change was lower in amplitude. The integrative analysis of miRNA and mRNA expression showed that, among the 40 differentially expressed known miRNAs and 388 differentially expressed genes, 60 pairs of miRNA/mRNA were identified as co-expressed in our present study. These results suggest that both miRNA and mRNA may play a pivotal role in the process of learning and memory in honeybees. Our sequencing data provide comprehensive miRNA and gene expression information for maze-based visual learning, which will facilitate understanding of the molecular mechanisms of honeybee learning and memory.

关键词： Apis mellifera Y-maze learning and memory microRNA DGE differential expression