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含环醚结构的生物基二醇对环己烷二甲醇基聚碳酸酯的性能调控

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复合材料学报 2024年第7期41卷 3598-3608页

作者：于化童蔡晓东杨烨鑫焦丹花张道海贵州民族大学化学工程学院贵阳550025 贵州民族大学材料科学与工程学院贵阳550025

1,4-环己烷二甲醇基聚碳酸酯具有优异的热力学性能,但因其降解性能的影响,商业应用受到极大的限制。向其分子链中引入脂肪族单元可以有效提高降解能力,但却以牺牲其热力学性能为代价。因此,为了维持热力学与降解性能间的平衡,本文以具... 详细信息

1,4-环己烷二甲醇基聚碳酸酯具有优异的热力学性能,但因其降解性能的影响,商业应用受到极大的限制。向其分子链中引入脂肪族单元可以有效提高降解能力,但却以牺牲其热力学性能为代价。因此,为了维持热力学与降解性能间的平衡,本文以具有环醚刚性的生物基2,5-四氢呋喃二甲醇(THFDM)为改性单元,采用熔融酯交换缩聚法成功制备了高分子量聚(碳酸1,4-环己烷二甲醇酯-co-碳酸2,5-四氢呋喃二甲醇酯)(PCThC)共聚物。通过NMR图谱探究共聚物的组成和微观结构,证实了共聚物组分间的无规分布;DSC和WAXD图谱结果表明,THFDM单元的引入破坏了PCThC分子链的规整排列,使其结晶能力降低,共聚物从半结晶型过渡到无定型。THFDM中的刚性环结构有效阻止了共聚物玻璃转化温度(Tg)的快速下降,保持其较好的热稳定性;THFDM分子中的环结构赋予了聚合物更高的刚度,提高了聚合物的力学性能;此外,THFDM中的醚键改善了PCThC共聚物的亲水性,加快了水解速率,不论是在酸性或碱性缓冲溶液中,共聚物均表现出一定的降解能力。

关键词：生物基聚碳酸酯共聚改性四氢呋喃二甲醇环醚结构性能调控

Abundance and biomass of heterotrophic microbes in the Kongsfjorden, Svalbard

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Acta Oceanologica Sinica 2005年第6期24卷 143-152页

作者： JIANG xiaodong HE Jianfeng cai Minghong State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China

Abundance and biomass of heterotrophic microbes were investigated usingepifluorescense microscopy in August 2004 along a transect in the Kongsfjorden, a glacial fjord inthe high arctic, located in the north-western part of Svalbard. A bacterial abundance was low atouter fjord stations (on average 2.29 x 10~8 ind./dm^3) and was higher at inner fjord stations (onaverage 3.52 x 10~8 ind./dm^3).The biomass of bacteria ranged from 3.69 to 8.01 mg/m^*** abundanceof bacteria was low at the surface of water(0 m), whereas the higher abundances often occurred atdepths of 30～50 *** abundance of heterotrophic flagellates varied from 2.785 to 8.891 x 10~4 ind./dm^3. The assemblage was numerically dominated by less than 5 μm heterotrophic flagellates(78.67%～94.80%).The biomass of heterotrophic flagellates varied from 0.37 to 2.30 mg/m^*** meanbiomass distribution for all stations was 4.91% for less than 5 μm heterotrophic flagellates,86.74% for 6～20 μm flagellates and 8.35% for greater than 20 μm sized *** low biomassof heterotrophic flagellates often occurred at the surface of water (0 m),while the maximum valueof biomass occurred at different depths. The biomass of total heterotrophic microbial communityranged from 4.20 to 10.03 mg/m^*** mean biomass distribution for all stations was 82.58% forbacteria, 15.77% for flagellates and 1.66% for ciliates.

关键词： abundance biomass bacteria flagellate kongsfjorden

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超深碳酸盐岩裸眼分段完井可溶球研究与应用

石油机械 2024年第6期52卷 58-63页

作者：黄亮张永峰张杰鲁刚吴春洪蔡小东中国石油化工集团有限公司碳酸盐岩缝洞型油藏提高采收率重点实验室新疆乌鲁木齐830000 中国石油化工股份有限公司西北油田分公司中石化江汉石油工程有限公司井下测试公司

针对顺北油田5号条带超深碳酸盐岩储层裸眼分段完井工艺特点,研究设计了一种可控溶解的压裂球,主要用以解决“高耐酸腐蚀性、高速溶解特性、耐高压性能”等3个问题。可溶球采用“基体+涂层”结构,基体材料采用镁铝合金,涂层优选改性聚... 详细信息

针对顺北油田5号条带超深碳酸盐岩储层裸眼分段完井工艺特点,研究设计了一种可控溶解的压裂球,主要用以解决“高耐酸腐蚀性、高速溶解特性、耐高压性能”等3个问题。可溶球采用“基体+涂层”结构,基体材料采用镁铝合金,涂层优选改性聚四氟乙烯+酚醛树脂纳米材料,并使用有机涂层对镁铝合金进行表面处理。对新研制的可溶球分别进行了承压数值仿真分析、耐酸承压测试和高温溶解测试,最后在顺北4-13H井进行了现场应用。研究结果表明:新研制的可溶球能够承受高温160℃、高压70 MPa、耐酸且能高速溶解,平均溶解速率为7.19 g/h,完全溶解只需12 h左右,实现了压裂时承压、生产时快速溶解不堵塞通道的双重要求,能有效提高可溶球在顺北区块裸眼分段完井工艺中的适用性和有效性,满足现场使用需求。研究结果可为油田现场水平井分段完井工艺提供参考。

关键词：超深碳酸岩裸眼井压裂球分段完井滑套可溶解

A novel ethanol-based method to induce differentiation of adipose-derived stromal cells into astrocytes

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Neural Regeneration Research 2011年第10期6卷 738-743页

作者： Ya Ou xiaodong Yuan Yanan cai Yanhui Lu Department of Neurology Kailuan General Hospital Hebei United University Tangshan 063000 Hebei Province China

The quantity and survival time of astrocytes,which were differentiated from adult adipose-derived stromal cells after exposure to an inducer containing 3-isobutyl-1-methylxanthine,have thus far been *** present study investigated the growth and differentiation characteristics of induced astrocytes by observing their growth *** induction for 48 hours with an inducer containing 0.5% ethanol,some adult adult adipose-derived stromal cells displayed typical astrocytic *** cell quantity gradually decreased with prolonged induction ***,glial fibrillary acidic protein,and S-100 expression reached peak levels at 14 days,but neuron-specific enolase was not *** results suggest that the induced astrocytes reached their peak at 14 *** optimization of the culture environment may yield mature astrocytes with normal functions,in greater quantity,and prolonged survival time.

关键词： adult adipose-derived stromal cells induced differentiation astrocyte morphology growth characteristics neural regeneration

Apoptosis during β-mercaptoethanol-induced differentiation of adult adipose-derived stromal cells into neurons

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Neural Regeneration Research 2011年第10期6卷 750-755页

作者： Yanan cai xiaodong Yuan Ya Ou Yanhui Lu Department of Neurology Kailuan General Hospital Hebei United University Tangshan 063000 Hebei Province China

β-mercaptoethanol can induce adipose-derived stromal cells to rapidly and efficiently differentiate into neurons in ***,because of the short survival time of the differentiated cells,clinical applications for this technique are *** such,we examined apoptosis of neurons differentiated from adipose-derived stromal cells induced with β-mercaptoethanol in vitro using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and transmission electron *** results revealed that the number of surviving cells decreased and apoptosis rate increased as induction time *** together,these results suggest that apoptosis occurring in the process of adipose-derived stromal cells differentiating into neurons is the main cause of cell ***,the mechanism underlying cellular apoptosis should be researched further to develop methods of controlling apoptosis for clinical applications.

关键词： adult adipose-derived stromal cells induced differentiation neurons ultrastructure apoptosis 13-mercaptoethanol neural regeneration

Study on Polyurethane/(vinyl ester resin) IPN Damping Materials

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Journal of Materials Science & Technology 2003年第z1期19卷 56-58页

作者： Chuanli QIN Dongyan TANG Jun cai Jusheng.ZHANG Weimin cai xiaodong SUN Department of Environmental Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Environmental Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Environmental Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200030 China The Army Representative Agency in 674 Factory State-Owned Harbin 151005 China

Polyurethane/(vinyl ester resin) interpenetrating polymer network (PU/VER IPN) materials with broad temperatureranges and excellent damping properties from Iow temperature to room temperature were prepared. The influenceof comonomers and component ratios on the compatibility and damping properties of IPN materials was studied byDMA which indicates that such properties are improved by introducing acrylic esters instead of polystyrene (PSt)into VER comonomer system. The detected results of microstructure by AFM show that the phase ranges of thedual-phase continuous IPN materials obtained are both in nanometer scale. The results of mechanical propertiesshow that IPN materials show the regulation from elastic deformation to brittle deformation with the increase of VERproportion.

关键词： Interpenetrating polymer network, Vinyl ester resin, Damping materials, Compatibility

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一种高效星载功率调节与配电单元设计与实现

航天器工程 2024年第1期33卷 42-48页

作者：蔡晓东杜青徐泽锋张俊亭杨袆夏宁王超北京空间飞行器总体设计部北京100094 上海空间电源研究所上海200245

文章结合深空探测供配电分系统任务特点,提出功率调节、配电、火工控制等多功能模块轻小型一体化设计的必要性。介绍了国外功率调节与配电单元的研究现状、国产功率调节与配电单元研制的意义,功率调节与配电单元组成及功能设计,并通过... 详细信息

文章结合深空探测供配电分系统任务特点,提出功率调节、配电、火工控制等多功能模块轻小型一体化设计的必要性。介绍了国外功率调节与配电单元的研究现状、国产功率调节与配电单元研制的意义,功率调节与配电单元组成及功能设计,并通过多母线融合设计、多路放电均流设计、单元集成化设计等关键技术,解决了深空探测器高可靠轻小型化功率调节与配电单元设计难题。在轨飞行结果表明:功率调节与配电单元功能正常,工作可靠,性能优良。功率调节与配电单元的国产化设计实现,可为其它航天器的设计提供参考和借鉴。

关键词：深空探测高功率质量比功率调节与配电单元

Mitochondrial Genome of Callus Protoplast Has a Role in Mesophyll Protoplast Regeneration in Citrus: Evidence From Transgenic GFP Somatic Homo-Fusion

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Horticultural Plant Journal 2017年第5期3卷 177-182页

作者： cai xiaodong FU Jing GUO Wenwu Key Laboratory of Horticultural Plant Biology (Ministry of Education) College of Horticulture and Forestry Sciences Huazhong Agricultural University College of Horticulture and Gardening Yangtze University

Protoplast fusion has great potential in citrus improvement. Although citrus mesophyll protoplasts usually cannot divide and regenerate,symmetric protoplast fusion of embryogenic callus protoplast + mesophyll protoplast sometimes results in the regeneration of mesophyllparent-type cybrids. It suggested that mitochondrial DNA(mt DNA) from protoplasts of embryogenic callus parent plays an important role in stimulating division and regeneration of mesophyll protoplasts. Herein, somatic fusion was conducted via electrofusion between callus protoplasts isolated from Valencia orange [Citrus sinensis(L.) Osbeck] cell suspension cultures and transgenic GFP-tagged mesophyll protoplasts from the same genotype, i.e. transgenic Valencia orange plants containing the green fluorescent protein(GFP) gene, in an effort to elucidate whether mt DNA of callus line could stimulate the division and regeneration of mesophyll protoplasts from the same genotype. Two embryoids and one plantlet with GFP expression were successfully obtained and subsequent ploidy analysis by flow cytometry indicated that they were all diploids. The regenerated diploid embryoids and plantlet with GFP expression could be considered as ‘cybrids' with mt DNA from the callus protoplasts of Valencia orange. The result indicated that citrus mesophyll-parent-type cybrid regeneration needed the stimulation of mt DNA from protoplasts of embryogenic callus parent regardless of their origin either from another genotype or the same genotype as the mesophyll parent.

关键词： citrus cybrid mitochondrial DNA(mtDNA) callus protoplast mesophyll somatic hybridization

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我国生姜产业近10年的产销状况及发展策略

中国瓜菜 2024年第2期37卷 150-155页

作者：赵小琴蔡小东刘奕清叶亮朱学栋王显凤长江大学园艺园林学院·香辛作物研究院湖北荆州434025 宜昌犁沣农业科技有限责任公司湖北宜昌443113 重庆市渝东南农业科学院重庆400800 重庆市永川区经济作物技术推广站重庆402160

生姜(Zingiber officinale Rosc.)是食药同源的香辛蔬菜,经济效益位居农作物前列,在巩固脱贫攻坚成果衔接乡村振兴中发挥着积极作用。对近10年来我国生姜产业的产销状况和存在的问题进行分析,对未来发展提出建议,以供相关决策者和广大... 详细信息

生姜(Zingiber officinale Rosc.)是食药同源的香辛蔬菜,经济效益位居农作物前列,在巩固脱贫攻坚成果衔接乡村振兴中发挥着积极作用。对近10年来我国生姜产业的产销状况和存在的问题进行分析,对未来发展提出建议,以供相关决策者和广大从业者参考。

关键词：生姜产销状况存在问题发展策略