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This study is the first step to investigate usability of shape memory polyurethane (SMPU) fibers for smart garment applications. SMPU fibers were spun by wet spinning process and chemical/mechanical characterization was carried out. SMPU solutions were prepared with two different concentrations (20 % and 25 %) and three different coagulation bath concentrations (0 %, 1 % and 3 %) were used for determining optimum spinning parameters. For investigating influences of spinning process on crystal structure, mechanical, thermal and shape memory performances of fibers, X-ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM) and mechanical tests were conducted. DSC and DMA analysis results show that shape memory polyurethane fibers have a glass transition temperature about 35-40 oC which is suitable for body temperature. Moreover, SMPU fibers showed good tensile performance with an average tenacity of 1.38 cN/dtex and elongation at break of 350 %. Thermo mechanical test results showed that, all shape memory fibers have good shape memory effect with recovery and fixity ratios up to 91 % and 71 % respectively. 相似文献
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Xinfeng Wu Bo Tang Jinhong Yu Xiao Cao Chongyin Zhang Yonggen Lv 《Fibers and Polymers》2018,19(1):170-187
Graphite reinforced hollow epoxy macrospheres (GR-HEMS) and hollow glass microspheres (HGMS) were used to prepare three phase epoxy syntactic foam (ESF) using “molding method”, and the physical and mechanical properties of ESF were also studied and investigated. An innovative “rolling ball method” was implemented in the GR-HEMS preparation process. The performance tests show that higher GR-HEMS stacking volume fraction, lower GR-HEMS thickness, higher GR-HEMS diameter, higher HGMS volume fraction, lower HGMS density are beneficial to reducing the density of ESF, but the effects of the five factors on the strength of ESF are the opposite. Therefore, in order to obtain “high strength and low density” ESF composites, the various factors should be considered to achieve a balance of the strength and the density. Scanning electron microscope (SEM) shows that the “rolling ball method” can make graphite form a graphite spherical x-y network throughout the macrosphere wall, which can make GR-HEMS and ESF have great compressive strength. The ESF (450 kg/m3, 20.75 MPa) can withstand the 2075 meters water pressure and provide 550 kg/m3 buoyancy, which can give some advice to the preparation of buoyancy material used in deepwater oil exploration. 相似文献
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QTL Detection for Rice Grain Shape Using Chromosome Single Segment Substitution Lines 总被引:1,自引:0,他引:1
Rice grain shape is one of the important factors affecting grain quality and yield,but it is liable to be influenced by genetic backgrounds and environments.The chromosome single segment substitution lines(SSSLs) in rice have been considered as ideal populations to identify the quantitative trait loci(QTLs).In this study,22 QTLs affecting rice grain shape were detected to be distributed on eight chromosomes except chromosomes 6,9,11 and 12 by using SSSLs.Among them,seven QTLs conditioned grain length,six co... 相似文献
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Veronica Piazza Ivanka Dragi? Kristina Sep?i? Marco Faimali Francesca Garaventa Tom Turk Sabina Berne 《Marine drugs》2014,12(4):1959-1976
Polymeric alkylpyridinium salts (poly-APS) isolated from the Mediterranean marine sponge, Haliclona (Rhizoniera) sarai, effectively inhibit barnacle larva settlement and natural marine biofilm formation through a non-toxic and reversible mechanism. Potential use of poly-APS-like compounds as antifouling agents led to the chemical synthesis of monomeric and oligomeric 3-alkylpyridinium analogues. However, these are less efficient in settlement assays and have greater toxicity than the natural polymers. Recently, a new chemical synthesis method enabled the production of poly-APS analogues with antibacterial, antifungal and anti-acetylcholinesterase activities. The present study examines the antifouling properties and toxicity of six of these synthetic poly-APS using the barnacle (Amphibalanus amphitrite) as a model (cyprids and II stage nauplii larvae) in settlement, acute and sub-acute toxicity assays. Two compounds, APS8 and APS12-3, show antifouling effects very similar to natural poly-APS, with an anti-settlement effective concentration that inhibits 50% of the cyprid population settlement (EC50) after 24 h of 0.32 mg/L and 0.89 mg/L, respectively. The toxicity of APS8 is negligible, while APS12-3 is three-fold more toxic (24-h LC50: nauplii, 11.60 mg/L; cyprids, 61.13 mg/L) than natural poly-APS. This toxicity of APS12-3 towards nauplii is, however, 60-fold and 1200-fold lower than that of the common co-biocides, Zn- and Cu-pyrithione, respectively. Additionally, exposure to APS12-3 for 24 and 48 h inhibits the naupliar swimming ability with respective IC50 of 4.83 and 1.86 mg/L. 相似文献
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利用重测序的染色体片段代换系群体定位水稻粒型QTL 总被引:1,自引:1,他引:1
以一套用籼稻品种9311为受体、粳稻品种日本晴为供体构建的128个染色体片段代换系为材料,按随机区组实验设计种植,于成熟后考查代换系粒长、粒宽性状,利用多元回归分析方法,结合Bin图谱,鉴定出6个与粒长相关的QTL、2个与粒宽相关的QTL。其中,qGL3.1被定位在水稻第3染色体的5 792 954 bp区间内;qGL3.2被定位在第3染色体的917 878 bp区间内;qGL8.1被定位在第8染色体的889 543 bp区间内;qGL8.2被定位在第8染色体的208 614 bp区间内;qGL9.1被定位在第9染色体的1 149 685 bp区间内;qGL11.1被定位在第11染色体的3 184 760 bp区间内;qGW1.1被定位在第1染色体的200 070 bp区间内;qGW5.1被定位在第5染色体的704 905 bp区间内。上述QTL的准确定位,为进一步精细定位及克隆相应QTL和开展水稻粒型分子育种奠定了基础。 相似文献
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利用高密度SNP标记定位水稻粒形相关QTL 总被引:1,自引:0,他引:1
《杂交水稻》2015,(5):54-58
以"巨穗稻"R1128与粳稻品种日本晴杂交,构建包含781个单株的F2分离群体,利用高通量测序技术开发高密度SNP标记并构建超高密度的遗传连锁图谱,对水稻粒长、粒宽和粒厚3个性状进行QTL定位分析。共检测到分布于除第1,11,12号染色体以外的9条染色体上的19个粒形相关QTL,其中10个控制粒长,5个控制粒宽,4个控制粒厚,这些QTL中,粒长QTL q GL4-2、q GL7-2、q GL10-2、q GL10-3,粒宽QTL q GW6,粒厚QTL q GT4、q GT8可能为新发现的粒形相关位点。 相似文献
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利用重测序的水稻染色体片段代换系群体定位剑叶形态QTL 总被引:1,自引:1,他引:1
剑叶形态性状(剑叶长、剑叶宽和剑叶面积)是水稻理想株型育种的重要目标性状之一。发掘新的控制水稻剑叶形态性状的基因资源,准确鉴定和定位水稻剑叶形态性状QTL,对开展水稻剑叶形态性状分子生物学研究和理想株型分子育种都具有重要意义。 以通过高通量测序而准确获知代换片段位置及长度的一套用籼稻品种9311为受体、粳稻品种日本晴为供体构建的,包括128个染色体片段代换系群体为材料,对剑叶形态性状及其与主穗颖花之间的相关性进行分析,结果表明剑叶面积与剑叶长、宽呈极显著正相关,主穗颖花数与剑叶长、剑叶面积呈极显著正相关。利用多元回归分析方法,结合Bin map,共鉴定出与水稻剑叶长、宽和面积相关的QTL分别为4、4和6个,贡献率介于4.08%~60.40%。上述QTL的准确定位,为进一步精细定位及克隆相应QTL以及开展水稻剑叶形态性状分子育种奠定了基础。 相似文献
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【目的】CRISPR/Cas9基因编辑技术已成为水稻分子育种的重要手段。为了促进水稻育种的发展,本研究以非香型粳稻品种龙粳11为试验材料,对GS3、GS9和Badh2基因进行编辑,以期获得能稳定遗传的长粒香水稻材料。【方法】利用CRISPR/Cas9技术,以GS3、GS9和Badh2为靶基因,构建敲除载体pYLCRISPR/Cas9-GS3/ GS9/Badh2-gRNA,通过农杆菌介导法,在龙粳11的GS3、GS9和Badh2基因中引入了特定的突变。【结果】T2代无转基因的gs3/gs9/badh2纯合突变体与野生型龙粳11相比,粒长增加26.43%~27.01%,单株产量增加10.82%~12.11%,千粒重增加18.34%~41.36%,稻米变香,高效地将圆粒水稻变成长粒香型水稻。【结论】利用CRISPR/Cas9技术获得能够稳定遗传并具有长粒香品质的纯合突变株系,为组合多个品质性状提供了一种方便有效的方法,从育种角度加快了新品系创制过程。 相似文献
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【Objective】 CRISPR/Cas9-mediated genome editing has become an important way for molecular breeding in rice. To promote rice breeding, the non-fragrant japonica rice variety Longjing11 was used as the test material. This study aims to edit GS3, GS9 and Badh2 genes for obtaining valuable and stable long-grain fragrant rice materials. 【Method】 The target genes GS3, GS9 and BADH2 were selected to construct the vector pYLCRISPR/ Cas9-GS3/ GS9/Badh2-gRNA by using CRISPR/Cas9 gene editing technology. The Agrobacterium-mediated transformation was used to transform Longjing11. Specific mutations were introduced into the GS3, GS9 and Badh2 genes in Longjing 11. 【Result】 The grain length of the transgenic free homozygote gs3/gs9/badh2 increased by 26.43% to 27.01%, yield per plant by 10.82% to 12.11%, 1000-grain weight by 18.34% to 41.36%, rice became fragrant as compared with wild type of Longjing 11. This study efficiently transformed round-grain rice into long-grain fragrant rice. 【Conclusion】The homozygous mutant lines featured by stable inheritance and long-grain fragrant quality were obtained by using CRISPR/Cas9 system. This study provides a convenient and effective way of combining multiple quality traits together, which could significantly accelerate breeding process from a breeding perspective. 相似文献
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【目的】粒重粒形是影响水稻产量和品质的重要因素,由大量数量性状座位(QTL)控制,其作用变异极大,但以往研究主要着眼于效应大的QTL。本研究在剔除主效QTL影响的基础上,开展微效粒重粒形QTL分析。【方法】在前期研究基础上,从原群体挑选出1个剩余杂合体单株,构建了在主效QTL区间纯合、在其余区域中13个区间分离的群体,种植于浙江杭州和海南陵水,测定千粒重、粒长和粒宽。【结果】采用Windows QTL Cartographer2.5,检测到22个QTL,分布于10条染色体的12个区间,其中,10个区间在两地均呈显著作用,2个区间仅在杭州试验中呈显著作用。进一步从该群体筛选出1个只在其中4个QTL区间杂合的单株,自交构建分离群体,验证了这4个区间对粒重粒形的效应。【结论】排除主效QTL有利于提高微效粒重粒形QTL的检测功效;虽然微效QTL可能易受环境和遗传背景影响,但仍可具有稳定表现。这些结果为进一步开展粒重粒形QTL的精细定位、克隆和分子标记辅助选择奠定了基础。 相似文献
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《杂交水稻》2014,(6):50-55
以东乡野生稻/协青早B∥协青早B的回交自交系群体为遗传材料,利用简化基因组测序技术鉴定群体的SNP分子标记基因型,对东乡野生稻的粒形相关性状进行QTL分析。在水稻第1,3,4,5,10,12号染色体上共发现14个粒形相关QTL,包括6个粒长QTL(q GL1、q GL3.1、q GL3.2、q GL4、q GL10.1、q GL10.2)、2个粒厚QTL(q GT5、q GT10)和6个粒重QTL(q KGW3、q KGM4、q KGW5、q KGW 10.1、q KGW10.2、q KGW12)。其中q GL3.1与q KGW3、q GT5与q KGW5、q GL4与q KGM4、q GL10.1与q KGW10.1以及q GL10.2、q GT10与q KGW10.2定位区间重叠,推测这些QTL具有一因多效特性。加性效应最大的粒长QTL即q GL3.1(q KGW3)被定位在第3染色体的粒形基因GS3的区域中,且q GL3.1与GS3都是控制粒长的主效QTL,推测q GL3.1就是GS3基因。而在q GL3.1区域附近还存在粒长QTL q GL3.2,该位点与已克隆的粒长QTL即GL3.1在位置上重叠,推测q GL3.2可能就是GL3.1/Os PPKL1基因。 相似文献
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制造球形天然橡胶的全胶凝技术 总被引:2,自引:0,他引:2
在深入分析天然胶乳凝固机理的基础上,采用全胶凝技术进行了球形天然橡胶半工业规模的试验.试验流程由分散、胶凝、陈化、洗涤、过滤等组成的湿法工序以及流态化干燥机为中心的干法工序组成.试验内容包括胶乳的分散及其在乳化液中的相变凝固和在水溶液中的收缩凝固、溶胶改性和凝胶隔离以及流态化干燥机的运行等.相变凝固剂是由乙酸和草酸与辛醇配置的乳化溶液;收缩凝固剂组成为酸性电解质水溶液.溶胶改性是向胶乳中添加硅溶胶;凝胶隔离是在乳化液中添加纳米滑石.球形凝胶的干燥是在由热风炉、风机、布风板、卧式搅拌浆以及过滤板等组成的流态化干燥机组内完成的.试验结果证明:全胶凝技术已经取得了工程应用的可行性论证.新工艺的特点是先成滴后凝固,而传统的标准胶工艺是先凝固后粉碎.二者相比,新工艺具有节省设备和动力、流程简短、操作方便、成本低廉、废水少、产品流动性和配合性好等诸多优点.新工艺在经济效益、社会效益以及环保效益等方面的潜力较大. 相似文献