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电子竞技杂志微博——我们只关注电竞
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《电子竞技》 2016年第5期118-119,共2页
你来我往之微交流本刊腾讯微博:http://t.qq.com/cea-cn 新浪、腾讯微博互动版块 电子竞技杂志:闲言碎语--不论是刀圈和刀友间,还是撸圈和撸友间,还是刀撸之间??咱们一定要和谐,您说是不是这个理儿!一起成长,一起进步??
关键词 竞技 腾讯 DOTA http 实况录像 大成子 最佳男主角 世界大赛 FEELING 双修
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Chemical constituents from Xylosma controversum 被引量:2
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作者 徐正仁 陆亚男 +2 位作者 柴兴云 任宏燕 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第3期218-222,共5页
Aim To study the chemical constituents from the stems of Xylosma controversum Clos. Methods The constituents were isolated by solvent extraction, repeated chromatography with silica gel, Sephadex LH-20, and RP-18 colu... Aim To study the chemical constituents from the stems of Xylosma controversum Clos. Methods The constituents were isolated by solvent extraction, repeated chromatography with silica gel, Sephadex LH-20, and RP-18 columns. The structures were elucidated by spectral analysis. Results Thirteen compounds were isolated and their structures were identified as (-)-syringaresinol (1), syringaresinol-4-O-β-D-glucopyranoside (2), syringaresinol-4,4′-bis-O-β-D-glucopyranoside (3), (±)-catechin (4), catechin-3-O- β-D-glucopyranoside (5), catechin-5-O-β-D-glucopyranoside (6), 1,3-bis-(4-hydroxy-3,5-dimethoxyphenyl)-1,3-propanediol (7), (R)-(+)-chaulmoogric acid (8), friedelin (9), uracile (10), benzoic acid (11), vaniUic acid (12), and 4-hydroxybenzoic acid (13). Conclusion All the compounds described above were isolated from this genus for the first time. 展开更多
关键词 FLACOURTIACEAE Xylosma controversum Chemical constituents
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Proton pump inhibitor induced collagen expression in colonocytes is associated with collagenous colitis 被引量:6
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作者 Shiori Mori Yui Kadochi +6 位作者 Yi Luo Rina Fujiwara-Tani Yukiko Nishiguchi Shingo Kishi Kiyomu Fujii Hitoshi Ohmori Hiroki Kuniyasu 《World Journal of Gastroenterology》 SCIE CAS 2017年第9期1586-1593,共8页
To elucidate the role of proton pump inhibitors (PPIs) in collagenous disease, direct effect of PPI on colonocytes was examined.METHODSCollagenous colitis is a common cause of non-bloody, watery diarrhea. Recently, th... To elucidate the role of proton pump inhibitors (PPIs) in collagenous disease, direct effect of PPI on colonocytes was examined.METHODSCollagenous colitis is a common cause of non-bloody, watery diarrhea. Recently, there has been increasing focus on the use of proton PPIs as a risk factor for developing collagenous colitis. Mouse CT26 colonic cells were treated with PPI and/or PPI-induced alkaline media. Expression of fibrosis-associated genes was examined by RT-PCR. In human materials, collagen expression was examined by immunohistochemistry.RESULTSCT26 cells expressed a Na<sup>+</sup>-H<sup>+</sup> exchanger gene (solute carrier family 9, member A2). Treatment with PPI and/or PPI-induced alkaline media caused growth inhibition and oxidative stress in CT26 cells. The treatment increased expression of fibrosis inducing factors, transforming growth factor β and fibroblast growth factor 2. The treatment also decreased expression of a negative regulator of collagen production, replication factor C1, resulting in increased expression of collagen types III and IV in association with lipid peroxide. In biopsy specimens from patients with collagenous colitis, type III and IV collagen were increased. Increase of type III collagen was more pronounced in PPI-associated collagenous colitis than in non-PPI-associated disease.CONCLUSIONFrom these findings, the reaction of colonocytes to PPI might participate in pathogenesis of collagenous colitis. 展开更多
关键词 Proton pump inhibitor Collagenous colitis PH FIBROSIS Oxidative stress
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Synthesis of PPy-like Nanocrystallines by Oriented Plasma Polymerization at Atmospheric Pressure
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作者 方忻生 郭颖 +1 位作者 徐金州 张菁 《Journal of Donghua University(English Edition)》 EI CAS 2006年第3期64-66,共3页
Polymeric polypyrrole-like (PPy-llke) nanocrystallines were fast synthesized through oriented plasma polymerization at atmospheric pressure and room temperature. The effects of discharge power on the nanocrystalline... Polymeric polypyrrole-like (PPy-llke) nanocrystallines were fast synthesized through oriented plasma polymerization at atmospheric pressure and room temperature. The effects of discharge power on the nanocrystalline morphology were investigated. Larger power tends to produce longer nanocrystallines. 3 mm long nanowires were produced at the largest power in our experiment. TEM image and the sharp electronic diffraction spots in SAD suggest that the nanoparticles have a single crystal phase. The chemical structure of the nanocrystalline has been studied through FTIR, EDX etc. This novel polymerization method could have great applications in fabricating functional polymeric nanocrystallines. 展开更多
关键词 atmospheric oriented plasma polymerization pol ypyrrole PP y) nanocrysllines.
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Cultivation Practice of Pleurotus Fossulatus on Rice Straw
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作者 Nirmalendu Das Protik Chowdhury Birja Pasman 《Journal of Life Sciences》 2010年第5期20-24,共5页
Pleurotusfossulatus, a member of oyster mushrooms, was successfully cultivated on rice straw. At least two flushes of fruit body developed at 22 ℃. The first flush of fruit body initiation took place on the 21 st day... Pleurotusfossulatus, a member of oyster mushrooms, was successfully cultivated on rice straw. At least two flushes of fruit body developed at 22 ℃. The first flush of fruit body initiation took place on the 21 st day and second one appeared on 38th day. The biological efficiencies (BE) were found to be 30.8% and 14.6% for first and second flush, respectively. The differentiation pattern of pileus and gills of this mushroom was found to be different from that of other reported species of oyster mushroom. The mushroom (P. fossulatus) took about 20 days for spore formation from primordia initiation and this time span was noted to be highest among all the published reports about any other Pleurotus spp. The BE were 25.9% and 12.5% in first and second flush, respectively when the mushroom was harvested on 18th day (after its initiation of primordia), i.e., before gill formation. However, the BE was found to be 14-16% lesser in comparison to that harvested after sporulation. 展开更多
关键词 CULTIVATION Pleurotusfossulatus spore allergy SPORULATION
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Learning L2 English in Tandem Partnerships On-Line
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作者 Noccetti Sabrina 《Sino-US English Teaching》 2012年第7期1318-1324,共7页
Tandem learning via email and computer-mediated communication activities flanked standard frontal English lessons for Italian adult learners in Italy. It is here suggested that the combination of tandem learning, vari... Tandem learning via email and computer-mediated communication activities flanked standard frontal English lessons for Italian adult learners in Italy. It is here suggested that the combination of tandem learning, various communication activities performed on-line, and standard courses help mature students to boost their self-esteem, give them more autonomy, and enhance their motivation. Tandem learning, which is based on the principles of reciprocity and autonomy, is ideally suited for adult students. It helps overcome the problems connected to the affective reactions of adults, and at the same time, being content driven, offers a more natural setting to learn an L2 (second language) on a mutual supportive basis. 展开更多
关键词 computer-mediated communication content and language integrated learning L2 (second language)learning tandem partnership
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Efficient synthesis of 1,6-hexamethylene diurethane through coupling transesterification and methoxycarbonylation with methyl phenyl carbonate as intermediate
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作者 杨勇 汤吉海 +3 位作者 陈献 费兆阳 崔咪芬 乔旭 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第7期1147-1152,共6页
A reaction coupling system of transesterification and methoxycarbonylation with methyl phenyl carbonate (MPC) as intermediate was established to efficiently prepare 1,6-hexamethylene diurethane (HDU) from 1,6- bex... A reaction coupling system of transesterification and methoxycarbonylation with methyl phenyl carbonate (MPC) as intermediate was established to efficiently prepare 1,6-hexamethylene diurethane (HDU) from 1,6- bexametbylene diamine (HDA). The feasibility of the system was explored using the thermodynamics analysis, the reaction mechanism and the experiment results. The optimal reaction was carried out to get higher HDU yield. The thermodynamic analysis showed that the metboxycarbonylation of HDA with MPC, the Gibbs free energy of which was negative, was a spontaneous process. Furthermore, the equilibrium constant of the methoxycarbonylation of HDA with MPC was much greater than that of the transesterification of dimethyl carbonate (DMC) with phenol, so the reaction coupling could be realized under mild conditions. The reaction mechanism analysis indicated that phenoxy anion was the key spedes for reaction coupling. Higher MPC concentration was detected when sodium phenoxide was used as transesterification reactant with DMC, since the phenoxy anion of sodium phenoxide could be dissociated more easily. Sodium pbenoxide was more suitable to prepare HHDU through reaction coupling. A yield of HDU as high as 98.3% could be reached under the optimal conditions of mPhONa/mDMC = 0.027 and nDMC/nHDa = 8/1 at 90 ℃ in 2 h. 展开更多
关键词 Methyl phenyl carbonate 1 6-Hexamethylene diurethane Transesterification Methoxyl carbonate Reaction coupling
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爱情摇一摇(电影文学剧本)
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作者 鲁文 《时代文学(上半月)》 2014年第10期111-129,共19页
主要人物小传牛宝宝——男一号,90后。西海岸集团企划助理。帅气、浪漫,敢爱敢恨,收获了真正的爱情,却面临最严峻的抉择,朝气勃勃的青春加入海水般苦涩的味道。严意如——女一号,21岁,尤若兰孙女,双向情感障碍患者,在上海做生意的父亲... 主要人物小传牛宝宝——男一号,90后。西海岸集团企划助理。帅气、浪漫,敢爱敢恨,收获了真正的爱情,却面临最严峻的抉择,朝气勃勃的青春加入海水般苦涩的味道。严意如——女一号,21岁,尤若兰孙女,双向情感障碍患者,在上海做生意的父亲托人找冯艳丽为其治疗,通过微信结识牛宝宝,由此开始一段一波三折的情感。 展开更多
关键词 冯艳丽 主要人物 男一号 若兰 情感障碍 小区门口 香水吧 大成子 铁栅栏 同班同学
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小干部岗位擂台赛体育委员篇
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《少先队小干部(综合版)》 2020年第4期18-19,共2页
本期主题体育委员对对碰据说,在北京市海淀区五一小学里,有两名优秀的体育委员,他们在小干部的岗位工作中,各有所长。本期,他们同时参加擂台赛活动。谁将是你心中的擂主呢?红队主帅风采我叫姜易成,是繁星中队的体育委员。在中队里,队员... 本期主题体育委员对对碰据说,在北京市海淀区五一小学里,有两名优秀的体育委员,他们在小干部的岗位工作中,各有所长。本期,他们同时参加擂台赛活动。谁将是你心中的擂主呢?红队主帅风采我叫姜易成,是繁星中队的体育委员。在中队里,队员们都喜欢称我为“大成子”。为什么呢?因为我从小就长得又高又壮! 展开更多
关键词 体育委员 干部岗位 对对碰 北京市海淀区 擂台赛 大成子 小学 队员
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守望
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作者 袁莉 《五台山》 2018年第6期36-41,共6页
1二月二龙抬头,鸡冠山脚下的王家庄一大早传出稀稀落落的几声二踢脚炮声后,又陷入一如既往的寂静中。刚吃过早饭,'噗,噗'一声炸响,惊得村里的人一震,原来是闲置已久的村里的喇叭在开机试用。很久没有动静了,今天这是咋了?'... 1二月二龙抬头,鸡冠山脚下的王家庄一大早传出稀稀落落的几声二踢脚炮声后,又陷入一如既往的寂静中。刚吃过早饭,'噗,噗'一声炸响,惊得村里的人一震,原来是闲置已久的村里的喇叭在开机试用。很久没有动静了,今天这是咋了?'村民们,村民们,咳.咳.吃过饭的人去村委会集合,咳咳.没吃饭的精干些。'老村长在一阵喘息后终于播完了这个通知。 展开更多
关键词 大成子 王家庄 黄土地
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Triterpenoids from the stems of Casearia velutina Bl.
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作者 李飞飞 郭志琴 +1 位作者 柴兴云 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2012年第3期273-277,共5页
To investigate the chemical components from the stems of Casearia velutina Bl.,the constituents were isolated by repeated chromatography with silica gel,Sephadex LH-20,and ODS columns.The structures were elucidated by... To investigate the chemical components from the stems of Casearia velutina Bl.,the constituents were isolated by repeated chromatography with silica gel,Sephadex LH-20,and ODS columns.The structures were elucidated by spectroscopic analysis.Eleven triterpenoids and its glycosides were isolated from the crude extract of C.velutina,and their structures were identified as friedelin-2,3-lactone(1),friedelane(2),epifriedelanol(3),friedelin(4),2α,3α,19α-trihydroxy-urs-12-en-28-oic acid(5),2α,3β,19α-trihydroxy-urs-12-en-28-oic acid(6),2α,3α,23-trihydroxy-urs-12-en-28-oic acid(7),2α,3α,23-trihydroxy-olean-12-en-28-oic acid(8),2α,3α,19α,23-tetrahydroxy-urs-12-en-28-oic acid(9),2α,3α,19α,23-tetrahydroxy-urs-12-en-28-oic acid-28-O-β-D-glucopyranosyl ester(10),and 3β,19α-dihydroxy-urs-12-en-28-oic acid 3-O-α-L-arabinopyranoside(11).All the compounds described above were isolated from this species for the first time.Compound 1 is a rarely occurred seco-friedelolactone in Flacourtiaceae. 展开更多
关键词 Casearia velutina Bl. FLACOURTIACEAE TRITERPENOID Chemical constituents
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Rapid room-temperature synthesis of hierarchical porous zeolitic imidazolate frameworks with high space-time yield 被引量:4
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作者 段崇雄 李非儿 +3 位作者 肖静 柳泽伟 李超 奚红霞 《Science China Materials》 SCIE EI CSCD 2017年第12期1205-1214,共10页
Hierarchical porous zeolitic imidazolate frameworks (ZIFs) have potential for adsorption, catalysis and chemical sensing applications. Ultrafast synthesis of ZIFs at room temperature and pressure is particularly des... Hierarchical porous zeolitic imidazolate frameworks (ZIFs) have potential for adsorption, catalysis and chemical sensing applications. Ultrafast synthesis of ZIFs at room temperature and pressure is particularly desirable for large-scale industrial production. Here, we developed a green and versatile method using organic amines as supramolecular templates (organic amine-template) to rapidly synthesize hierarchical porous ZIFs (ZIF-8, ZIF-61 and ZIF-90) at room temperature and pressure. The synthesis time was reduced dramatically to within 1 min, and the resulting ZIFs had multimodal hierarchical porous structures with mesopores/ macropores interconnected with micropores. Notably, the space-time yield (STY) of hierarchical porous ZIF-8 was up to 1.29×10^4 kg m^-3 d^-1, which is more than three times higher than that reported using other methods. Furthermore, the morphologies and porosities of the produced ZIFs could be readily tuned by controlling the synthesis time or type of organic amine. The organic amine played two roles in the synthesis: (1) a protonation agent to deprotonate organic ligands, facilitating the formation of ZIF crystals, and (2) an structure directing agent to direct mesopore/macropore formation. The resulting hierarchical porous ZIF-8 exhibited enhanced uptake capacities and diffusion rates for guest molecules relative to its microporous counterpart. This work provides a new direction for the green and efficient synthesis of various hierarchical porous ZIFs with high STYs for a wide range of applications. 展开更多
关键词 zeolitic imidazolate frameworks green and rapid synthesis hierarchical porous structure tunable morphology and porosity high space-time yield
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Intra-individual comparison of different gadolinium-based contrast agents in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging 被引量:4
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作者 Ying Li Gang Liu +2 位作者 Xin Lou Zhiye Chen Lin Ma 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第1期11-15,共5页
This experiment aimed to compare the ionic (Gadodiamide, Gd-DTPA-BMA) and non-ionic (Gadopentetate dimeglumine, Gd-DTPA) gadolinium-based contrast agents (GBCA) in the quantitative evaluation of C6 glioma with d... This experiment aimed to compare the ionic (Gadodiamide, Gd-DTPA-BMA) and non-ionic (Gadopentetate dimeglumine, Gd-DTPA) gadolinium-based contrast agents (GBCA) in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). A C6 glioma model was established in 12 Wistar rats, and magnetic resonance (MR) scans were performed six days after tumor implantation. Imaging was performed using a 3.0-T MR scanner with a 7-inch handmade circular coil. Pre-contrast T1 mapping and dynamic contrast-enhanced T1WI after a bolus injection (0.2 mL s 1) of GBCA at 0.4 mmol kg-1 were performed. Each rat received two DCE-MRI scans, 24 h apart. The first and second scans were performed using Gd-DTPA-BMA and Gd-DTPA, respectively. Image data were processed using the Patlak model. Both Kns and Vp maps were generated. Tumors were manually segmented on all 3D K and Vp maps. Pixel counts and mean values were recorded for use in a paired t-test. Three radiologists independently performed the tumor segmentation and value calculation. The agreements from different observers were subjective to the intra-class correlation coefficient (ICC). Readers demonstrated that the pixel counts of tumors in/Crns maps were higher with Gd-DTPA-BMA than with Gd-DTPA (P〈0.001, all readers). Although the/(r,,s values were higher with Gd-DTPA-BMA than with Gd-DTPA, there was no statistical significance (P〉0.05, all readers). The pixel counts of tumors in Vp maps, as well as Vp values, showed no obvious difference between the two agents (P〉0.05, all readers). Excellent interobserver measurement reproducibility and reliability were demonstrated in the ICC tests. The Gd-DTPA-BMA contrast agent had significantly higher pixel counts of glioma in the maps, and an increased tendency for average/Us values, indicating that DCE-MRI with Gd-DTPA-BMA may be more suitable and sensitive for the evaluation of glioma. 展开更多
关键词 dynamic contrast enhanced MR Ktrans Gd-DTPA-BMA GD-DTPA IONIC NON-IONIC
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Transient silencing mediated by in vitro synthesized double-stranded RNA indicates that PsCdc14 is required for sporangial development in a soybean root rot pathogen 被引量:3
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作者 ZHAO Wei YANG XinYu +3 位作者 DONG SuoMeng SHENG YuTing WANG YuanChao ZHENG XiaoBo 《Science China(Life Sciences)》 SCIE CAS 2011年第12期1143-1150,共8页
In many eukaryotic organisms, Cdcl4 phosphatase regulates multiple biological events during anaphase and is essential for mitosis. It has been shown that Cdcl4 is required for sporulation in the potato blight pathogen... In many eukaryotic organisms, Cdcl4 phosphatase regulates multiple biological events during anaphase and is essential for mitosis. It has been shown that Cdcl4 is required for sporulation in the potato blight pathogen Phytophthora infestans; howev- er, the role that the Cdcl4 homolog (PsCdcl4) plays in the soil-borne soybean root rot pathogen P. sojae remains ambiguous. PsCdc14 is highly expressed in spornlation, zoospore, and cyst life stages, but not in vegetative mycelia and infection stages, suggesting that it contributes to asexual reproduction and thus the spread of the disease. Double-stranded RNA (dsRNA) medi- ates gene silencing, a post-transcriptional and highly conserved process in eukaryotes, involving specific gene silencing through degradation of target mRNA. We combined in vitro dsRNA synthesis and a polyethylene glycol-mediated transfor- marion system to construct a dsRNA-mediated transient gene silencing system; and then performed a functional analysis of PsCdcl4 in P. sojae. PsCdc14 mRNA was dramatically reduced in transformants after protoplasts were exposed in in vitro synthesized PsCdc14 dsRNA, resulting in low sporangial production and abnormal development in P. sojae silencing lines. Furthermore, dsRNA-mediated transient gene silencing could enable elucidation of P. sojae rapid gene function, facilitating our understanding of the development and pathogenicity mechanisms of this oomycete fungus. 展开更多
关键词 Phytophthora sojae PsCdc14 sporangium transient gene silencing
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Molecular lines and continuum from W51A (I) --CO and NH_3 spectra and 3 mm continuum
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作者 裴春传 毛瑞青 曾琴 《Science China Mathematics》 SCIE 2001年第9期1209-1215,共7页
As for the 5′ × 4′(~llpc × 9pc) region centered at W51 lRSl the observations of the 3.4 mm continuum, CO (J = 1-0) line and simultaneous NH3(1,1), (2,2), (3,3), (4,4) inverse lines were made for studying ... As for the 5′ × 4′(~llpc × 9pc) region centered at W51 lRSl the observations of the 3.4 mm continuum, CO (J = 1-0) line and simultaneous NH3(1,1), (2,2), (3,3), (4,4) inverse lines were made for studying the massive star formation region located in the main spiral arms of the Galaxy. In the directions of W51 IRS1, IRS2 and el/e2 in 3.4 mm continuum, analyses of the line profiles show that the absorption lines of ammonia, which arise from the gas in front of the HII region, are red-shifted with respect to the emission lines, which arise from the surrounding cloud. Furthermore, a radiation transfer and statistical equilibrium calculation of ammonia molecules show that the densities increase by 3–10 times from the eastern border to the center. These points hint that the collapse is happening in the molecular cloud core obscured in optical wavelengths. The effects of the radiation fields from radio, infrared and UCHII sources is non-negligible on the excitation of various molecules (e.g. NH3) within the circle of radius 40″ centered at IRS1. The profiles of the COJ = 1–0 line in the circle change from double peaks ( ~ 60, ~ 68 km. s-1) to triple peaks, i.e. the component ~53 km·s?1, which associates with UCHII, also appears in the spectra. There are indications that the circle of radius 40″ centered at IRSI is a region of massive star forming activity 展开更多
关键词 massive star formation molecular hd collapse interstellar molecular be CONTINUUM
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Syntheses of bifunctional molecules containing [12]aneN_3 and carbazol moieties as effective DNA condensation agents 被引量:1
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作者 YAN Hao YUE Pan +2 位作者 LI ZhiFen GUO ZhiFo LU ZhongLin 《Science China Chemistry》 SCIE EI CAS 2014年第2期296-306,共11页
Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic ... Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic light scattering experiments, compounds 3 and 4b bearing both [12]aneN3 and carbazol moieties showed effective DNA condensation ability at the concen- tration of 80 jaM. Investigations from EB displacement fluorescence spectra, viscosity titration, and ionic strength effects re vealed that the effective DNA condensation comes from the appropriate combination of carbazol and [12]aneN3 units in the bifunctional molecules, and the DNA condensation process is reversible. The incorporation of triazole units in the molecules clearly reduced the cytotoxicity. 展开更多
关键词 DNA condensation macrocyclic polyamines CARBAZOLES TRIAZOLE gel electrophoresis AFM
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Recent advances of the Bergman cyclization in polymer science 被引量:2
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作者 Shudan Chen Aiguo Hu 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第11期1710-1723,共14页
The Bergman cyclization has strongly impacted on a number of fields including pharmaceutics, synthetic chemistry, and material science. The diradical intermediates stemmed from enediynes can not only cause DNA cleavag... The Bergman cyclization has strongly impacted on a number of fields including pharmaceutics, synthetic chemistry, and material science. The diradical intermediates stemmed from enediynes can not only cause DNA cleavage under physiological conditions but also function as monomer or initiator participants in polymer science. The homo-polymerization of enediynes through the Bergman cyclization to fabricate conjugated polymers is a fascinating strategy due to the advantages of facial operation, high efficiency, tailored structure, and catalyst-free operation. Moreover, conjugated polymers generated through the Bergman cyclization show many remarkable properties, such as excellent thermal stability, good solubility, and processability, which enables these polymers to be further manufactured into carbon-rich materials. Recent times have seen extensive efforts devoted to the application of the Bergman cyclization in polymer science and materials chemistry. A variety of synthetic strategies have been developed to fabricate structurally unique materials via the Bergman cyclization, including the fabrication of rod-like polymers with polyester, dendrimers and chiral imide side chains, functionalization of carbon nanomaterials by surface-grafting conjugated polymers, formation of nanoparticles by intramolecular collapse of single polymer chains, and the construction of carbon nanomembranes with different morphologies. Future developments involving the Bergman cyclization in polymer science, probably by altering the reaction mechanism to precisely control the microstructure of polymeric products, are also proposed in this review article. 展开更多
关键词 Bergman cyclization ENEDIYNES conjugated polymer carbon material
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Effect of catalyst confinement and pore size on Fischer-Tropsch synthesis over cobalt supported on carbon nanotubes 被引量:7
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作者 XIE Wei ZHANG YuHua +1 位作者 LIEW KongYong LI JinLin 《Science China Chemistry》 SCIE EI CAS 2012年第9期1811-1818,共8页
This paper studies the impact of structure of cobalt catalysts supported on carbon nanotubes(CNT) on the activity and product selectivity of Fischer-Tropsch synthesis(FTS) reaction.Three types of CNT with average pore... This paper studies the impact of structure of cobalt catalysts supported on carbon nanotubes(CNT) on the activity and product selectivity of Fischer-Tropsch synthesis(FTS) reaction.Three types of CNT with average pore sizes of 5,11,and 17 nm were used as the supports.The catalysts were prepared by selectively impregnating cobalt nanoparticles either inside or outside CNT.The TPR results indicated that the catalyst with Co particles inside CNT was easier to be reduced than those outside CNT,and the reducibility of cobalt oxide particles inside the CNT decreased with the cobalt oxide particle size increasing.The activity of the catalyst with Co inside CNT was higher than that of catalysts with Co particles outside CNT.Smaller CNT pore size also appears to enhance the catalyst reduction and FTS activity due to the little interaction between cobalt oxide with carbon and the enhanced electron shift on the non-planar carbon tube surface. 展开更多
关键词 carbon nanotube(CNT) cobalt catalyst CONFINEMENT pore size Fiseher-Tropsch synthesis
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Perylenediimide chromophore as an efficient photothermal agent for cancer therapy 被引量:1
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作者 Shaobo Zhang Jianhao Li +1 位作者 Jie Wei Meizhen Yin 《Science Bulletin》 SCIE EI CSCD 2018年第2期101-107,共7页
Photothermal agents with improved bioavailabilities can generate heat from near-infrared light, which has been efficiently used for in vivo photothermal therapy (PTT) for cancer, with minimum tissue invasion. Strate... Photothermal agents with improved bioavailabilities can generate heat from near-infrared light, which has been efficiently used for in vivo photothermal therapy (PTT) for cancer, with minimum tissue invasion. Strategies for developing organic near-infrared-absorbing molecules for phototfiermal cancer therapy have drawn intensive attention among academic investigators. However, conventional organic nearinfrared-absorbing molecules may not only have complex synthesis procedures, but also easily suffer from photobleaching under light irradiation. These drawbacks might lead to an increase in the synthesis cost, and elicit a risk of side effects in PTF. Thus, it is essential to devise an organic photothermal agent with stable phototbermal capacity, which involves a facile synthesis process. In this study, incorporating a secondary amine group (donor) in the bay regions of perylenediimides (PDls) could lead to a 150-nm bathochromic shift of the absorption maximum. Next, a modification of poly(ethylene glycol) (PEG) at the periphery of the chromophore renders the targeted macromolecule PDI-PEG highly water-soluble, and capable of intense absorption in the near-infrared region. The self-assembled PDl-based nanoparti- des (PDI-NPs) have a size of 55 nm in aqueous solutions. PDI-NPs with excellent photostability possess a high photothermal conversion efficiency of up to 43% ± 2%. Finally, PDI-NPs allow for efficient in vitro and in vivo photothermal cancer therapy. Meanwhile, PDI-NPs exhibit quite low cytotoxicity and no biotoxicity on major organs in vivo. Thus, these easily-manufactured PDI-NPs can serve as extremely stable photothermal agents for efficient photothermal cancer therapy. 展开更多
关键词 Perylenediimides Photothermal therapy Photostability Biotoxicity
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Probabilistic Remote Preparation of a Four-Particle Entangled W State for the General Case and for All Kinds of the Special Cases
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作者 戴宏毅 张明 +1 位作者 张祖荣 席在荣 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第9期313-322,共10页
We present a protocol for probabilistic remote preparation of a four-particle entangled W state. The quantum channel is composed of two partial entangled four-particle cluster states. We caiculate the total successful... We present a protocol for probabilistic remote preparation of a four-particle entangled W state. The quantum channel is composed of two partial entangled four-particle cluster states. We caiculate the total successful probability and total classical communication cost required for the general case and for all kinds of the special cases, respectively. It is shown that for two maximally entangled four-particle cluster states, such a scheme for the general case has the total successful probability of 25% and only consumes the total classical communication of I bit, while this scheme for the special cases under certain conditions can possess successful probability of 50% or 100%, the required classical communication will only be 2 bits or 4 bits. Meantime, we give in detail all unitary transformations for the general case and for all kinds of the special cases, respectively. 展开更多
关键词 remote state preparation four-particle W state cluster state classical communication cost
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