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液晶显示器模组黑态均匀性改善研究 被引量:6
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作者 李兴华 暴军萍 +1 位作者 徐兵 樊浩原 《液晶与显示》 CAS CSCD 北大核心 2018年第4期271-276,共6页
随着显示行业发展,市场对液晶显示品质提出了更高的要求,特别是车载等领域,背光亮度几乎在10 000cd/m2以上,此时显示装置的细微缺陷可能被凸显进而影响画面显示品质。黑态均匀性是液晶显示模组显示画质的重要指标,为提升液晶显示模组黑... 随着显示行业发展,市场对液晶显示品质提出了更高的要求,特别是车载等领域,背光亮度几乎在10 000cd/m2以上,此时显示装置的细微缺陷可能被凸显进而影响画面显示品质。黑态均匀性是液晶显示模组显示画质的重要指标,为提升液晶显示模组黑态均匀性,改善显示画质,特对可能造成黑态漏光的相应结构及设计进行研究。从液晶面板受外力方向,针对机构干涉及柔性电路板(FPC)应力两方面的影响因素设计实验,确定出利于提升黑态均匀性的设计方法或管控标准。实验结果表明,通过对背光及铁框平整度的管控及缓冲胶带优化可减少机构干涉应力,通过对FPC结构及外形设计优化可减少FPC弯折应力,通过玻璃厚度减薄及增大下偏光片尺寸可提升液晶面板抗变形能力,从而将模组黑态均匀性提升到80%以上。 展开更多
关键词 液晶显示器 黑态均匀性 机构干涉 FPC应力
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液晶显示器模组黑态漏光不良的改善研究
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作者 袁静 王顺 孙彦军 《科学技术创新》 2020年第15期138-139,共2页
随着科学技术的日趋高速发展,人们对电脑的美观也要求越来越高,液晶显示器模组黑态漏光的问题,会影响人们使用电脑的视觉效果。本文通过对电脑液晶显示器模组黑态漏光不良产生的原因进行归纳总结,进而提出解决液晶显示器模组黑态漏光不... 随着科学技术的日趋高速发展,人们对电脑的美观也要求越来越高,液晶显示器模组黑态漏光的问题,会影响人们使用电脑的视觉效果。本文通过对电脑液晶显示器模组黑态漏光不良产生的原因进行归纳总结,进而提出解决液晶显示器模组黑态漏光不良的改善方法。 展开更多
关键词 液晶显示器模组 黑态漏光不良 机构干涉应力 改善研究
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车载液晶显示器模组黑态均匀性改善研究 被引量:1
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作者 暴军萍 郁信波 +5 位作者 徐兵 王超 向西 杨小飞 李洋 罗宁 《光电子技术》 CAS 2022年第2期138-142,153,共6页
基于减小模组应力,系统的研究了工艺、材料、设计对黑态均一性的影响,确定出可满足70%面扫的方案。实验结果表明:1)模组设计上采用减薄至0.4 mm的液晶屏搭配1.3 mm厚度的盖板;2)材料选择使用上下材质一致的偏光片,液态光学贴合胶,低温... 基于减小模组应力,系统的研究了工艺、材料、设计对黑态均一性的影响,确定出可满足70%面扫的方案。实验结果表明:1)模组设计上采用减薄至0.4 mm的液晶屏搭配1.3 mm厚度的盖板;2)材料选择使用上下材质一致的偏光片,液态光学贴合胶,低温各向异性导电胶;3)对盒工艺降低机械臂运行速度,可将车载液晶显示器模组的面扫黑态均匀性提升到70%。 展开更多
关键词 智能驾驶 车载液晶显示器 黑态均匀性
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鄂东南湖泊水体中颗粒态黑碳分布特征与来源分析——以磁湖为例
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作者 陈颖颖 贺梦晴 +5 位作者 周倩 周玲 占长林 韩永明 柳山 方立虎 《环境化学》 CAS CSCD 北大核心 2024年第2期561-570,共10页
在地球水生态系统中,颗粒态黑碳(particulate black carbon,PBC)是颗粒有机碳(particulate organic carbon,POC)的重要组成部分.采用热光反射法对黄石磁湖POC、PBC及其组分(焦炭和烟炱)的含量水平、空间分布特征及可能来源进行了研究.... 在地球水生态系统中,颗粒态黑碳(particulate black carbon,PBC)是颗粒有机碳(particulate organic carbon,POC)的重要组成部分.采用热光反射法对黄石磁湖POC、PBC及其组分(焦炭和烟炱)的含量水平、空间分布特征及可能来源进行了研究.结果表明,磁湖水体中POC、PBC、焦炭(char)和烟炱(soot)含量变化范围分别为2899.38—5622.80、 235.01—800.08、 24.41—310.23、 130.09—544.72μg·L^(-1),平均含量分别为3903.84、377.25、155.52、272.65μg·L^(-1),呈现较大的空间分布差异.PBC/POC的变化范围在6.89%—18.32%之间,平均值为10.92%,说明城市湖泊水体中PBC对POC含量积累的贡献较大. soot/PBC的变化范围为45.92%—89.61%,平均值为63.95%. PBC、char与soot含量和PBC/POC比值的空间变异性与环湖周边区域的道路交通和工业布局有关,且南半湖受交通污染和工业排放的影响更大. PBC与POC、char和soot含量均呈正相关,且PBC与soot的相关系数(r=0.81,P<0.01)高于char(r=0.72,P<0.01),说明磁湖水体中soot对PBC的贡献更大. char/soot比值分析结果表明,磁湖水体中PBC主要受到交通污染源和燃煤等人类活动的影响. 展开更多
关键词 水体 颗粒有机碳 颗粒 分布 来源
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溶解态黑碳的来源、理化性质及环境效应 被引量:1
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作者 李亚玲 罗天烈 +4 位作者 陈贤 王柳瑾 杨敏慧 周成智 刘国 《生态毒理学报》 CAS CSCD 北大核心 2023年第4期148-161,共14页
黑碳是生物质与化石燃料不完全燃烧的产物,在环境介质中广泛存在,因其具有吸附、固碳、氧化还原等物理化学作用而备受关注。溶解态黑碳平均分子量约为1~10 kDa,O/C值约为0.5~0.8,含有丰富的芳香微域结构和极性基团。溶解态黑碳可作为环... 黑碳是生物质与化石燃料不完全燃烧的产物,在环境介质中广泛存在,因其具有吸附、固碳、氧化还原等物理化学作用而备受关注。溶解态黑碳平均分子量约为1~10 kDa,O/C值约为0.5~0.8,含有丰富的芳香微域结构和极性基团。溶解态黑碳可作为环境污染物的重要吸附载体,影响污染物在环境中的分配传输和生物利用度。因其结构中含有大量酚类、醌类等基团,溶解态黑碳可作为电子传递载体或反应物参与污染物的氧化还原过程。此外,溶解态黑碳具有光化学活性,其产生·OH、^(1)O_(2)和3 DBC*的表观量子产率分别约为(6~14)×10^(-5),(3.4~5.5)×10^(-2)和(4~7.5)×10^(-2),可通过光敏化作用影响有机污染物的光化学转化。本文基于大量文献调研,较系统地回顾梳理了有关溶解态黑碳的来源与赋存、理化性质和环境效应等方面的研究进展,并对未来研究做出评论和展望,旨在促进考虑溶解态黑碳影响污染物转化规律的相关研究。 展开更多
关键词 溶解 光化学活性 吸附 电子转移 光敏化作用
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海南东寨港流域土壤-溪流连续体溶解态黑碳分子特征及其界面转化机制
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作者 王全超 吉恒宽 +5 位作者 李思敏 李财生 侯正伟 邓万刚 吴治澎 王登峰 《生态环境学报》 CSCD 北大核心 2023年第1期139-149,共11页
研究不同土地利用背景下土壤-溪流连续体溶解态黑碳(DBC)分子特征及其界面转化规律对调控溪流温室气体排放具有重要的指导意义。以海南东寨港3个典型热带流域为研究区,对流域内3种土地利用类型(农田、林地、湿地)的土壤、溪流进行监测,... 研究不同土地利用背景下土壤-溪流连续体溶解态黑碳(DBC)分子特征及其界面转化规律对调控溪流温室气体排放具有重要的指导意义。以海南东寨港3个典型热带流域为研究区,对流域内3种土地利用类型(农田、林地、湿地)的土壤、溪流进行监测,通过超滤技术、苯多羧酸法与傅里叶变换离子回旋共振质谱技术(FT-ICR-MS)对DBC粒径分布、结构组成进行表征,进一步揭示不同土地利用背景下土壤-溪流界面中DBC转化机制。结果表明,从土壤到溪流环境DBC质量浓度逐渐变小;土壤DBC平均质量浓度、DBC/DOC比值大小顺序为湿地>农田>林地,而在溪流中湿地最低,分别为0.14 mg·L^(-1)、6.61%;林地、农田、湿地的土壤DBC分别主要分布在>10 kDa、<10 kDa、<1 kDa的粒径中,质量浓度范围为1.21—4.01 mg·L^(-1),所有溪流DBC在不同粒径中的分布更为均匀;所有土壤与溪流的DBC稠环结构以B4CAs和B5CAs为主,其中农田溪流B4CAs占比超过60%;DBC中CHO化合物的占比最高为73.56%,土壤DBC的CHOS/CHONS化合物在湿地中占比最高为21.84%,但在溪流DBC中湿地占比最低为6.73%;不同地类土壤-溪流界面中DBC含量平均损失率大小顺序为农田>林地>湿地,而林地、农田、湿地水土界面中具有最大损失率的DBC组分分别为>0.2μm、1—10 kDa、<1 kDa,而农田溪流中B3CAs、B4CAs和B5CAs平均损失率显著高于地类溪流。土壤-溪流界面的DBC转化主要受分子特征的影响,其次为界面环境理化性质与微生物组成,流域内不同土地利用方式通过改变土壤-溪流界面输入性DBC结构组成与界面环境因子共同影响DBC的界面转化过程。 展开更多
关键词 溶解 土地利用 土壤-溪流连续体 结构组成 界面转化
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武汉市大气干湿沉降中溶解态黑碳的季节分布特征 被引量:4
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作者 白冰冰 洪军 +4 位作者 李思思 刘佳 郭孟如 黄颖 孔少飞 《地球化学》 CAS CSCD 北大核心 2021年第1期46-55,共10页
本研究采集了武汉市城区2018年3月至2019年2月的大气总沉降及湿沉降样品,使用苯多羧酸法测定溶解态黑碳含量,并结合气象条件分析溶解态黑碳沉降通量季节变化特征及其影响因素。结果表明,总沉降中溶解态黑碳月浓度范围为0.12~0.83 mg/L,... 本研究采集了武汉市城区2018年3月至2019年2月的大气总沉降及湿沉降样品,使用苯多羧酸法测定溶解态黑碳含量,并结合气象条件分析溶解态黑碳沉降通量季节变化特征及其影响因素。结果表明,总沉降中溶解态黑碳月浓度范围为0.12~0.83 mg/L,均值为0.40 mg/L,湿沉降溶解态黑碳浓度范围为0.04~0.18 mg/L,均值为0.10 mg/L;溶解态黑碳总沉降和湿沉降年通量分别为269 mg·m^(−2)·a^(−1)和65 mg·m^(−2)·a^(−1)。溶解态黑碳总沉降通量季节变化为春季>冬季>夏季>秋季,湿沉降通量季节变化为冬季>春季>夏季>秋季。溶解态黑碳湿沉降通量主要受降雨量影响,而总沉降通量除受降雨量影响外还受风速、风向和空气质量等因素的共同影响。 展开更多
关键词 溶解 溶解性有机碳 干湿沉降 季节分布
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水体溶解态黑碳的分子标志物苯多羧酸的气相色谱-质谱分析 被引量:1
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作者 怡欣 钟广财 +4 位作者 孙悦 耿晓飞 莫扬之 李可昌 张干 《地球化学》 CAS CSCD 北大核心 2019年第3期276-283,共8页
苯多羧酸分子标志物法是定量水体中溶解态黑碳的常用方法,然而由于部分苯多羧酸,尤其是硝基苯多羧酸商业化标准品的缺失,采用该方法定量溶解态黑碳仍需进一步完善和优化。本文通过已有的苯多羧酸商业化标准品,建立了气相色谱-质谱联用仪... 苯多羧酸分子标志物法是定量水体中溶解态黑碳的常用方法,然而由于部分苯多羧酸,尤其是硝基苯多羧酸商业化标准品的缺失,采用该方法定量溶解态黑碳仍需进一步完善和优化。本文通过已有的苯多羧酸商业化标准品,建立了气相色谱-质谱联用仪(GC-MS)分离和定量 9 种缺少商业化标准品苯多羧酸的分析方法。并首次将菲-D10 作为溶解态黑碳的替代物,指示苯多羧酸法定量溶解态黑碳过程中的损失率。结果表明,该方法具有良好的重现性(RSD=10.34%),方法检出限为 0.67~5.38 ng/L。本文采用该方法分析了大亚湾表层水体溶解态黑碳的分布特征,其浓度范围为 30.38~46.19 μg/L,平均值为(38.93±6.17)μg/L,空间分布表现为从湾内到外海递减的趋势。 展开更多
关键词 气相色谱-质谱 溶解 苯多羧酸法 水体
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液相色谱-质谱法分析黑碳的分子标志物--苯多羧酸和硝基苯多羧酸 被引量:2
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作者 黄国培 陈颖军 +1 位作者 田崇国 刘莺 《色谱》 CAS CSCD 北大核心 2016年第3期306-313,共8页
苯多羧酸法是定量检测黑碳和溶解态黑碳的重要分子标志物法,其中苯多羧酸和硝基苯多羧酸的分离和定量是关键环节。本文建立了苯多羧酸和硝基苯多羧酸的液相色谱-质谱分析方法,利用质谱的定性能力解决了部分苯多羧酸和硝基苯多羧酸化合... 苯多羧酸法是定量检测黑碳和溶解态黑碳的重要分子标志物法,其中苯多羧酸和硝基苯多羧酸的分离和定量是关键环节。本文建立了苯多羧酸和硝基苯多羧酸的液相色谱-质谱分析方法,利用质谱的定性能力解决了部分苯多羧酸和硝基苯多羧酸化合物在缺乏标准品情况下的定性问题。用Phenomenex Synergi Polar RP分离柱,柱温为35℃,流动相为0.5%(体积分数)甲酸水溶液和甲醇,流速为0.5 mL/min,梯度洗脱,以电喷雾离子源负离子全扫描和选择扫描模式进行离子阱质谱检测,同时利用串联的二极管阵列检测器采集三维紫外光谱数据。在实际样品检测中,14个含3个及以上羧基的苯多羧酸和硝基苯多羧酸化合物获得良好分离。此方法简化并加快了苯多羧酸法定量黑碳和溶解态黑碳的分析过程,可满足环境样品中黑碳和溶解态黑碳的分析,促进了苯多羧酸法应用的普及。 展开更多
关键词 液相色谱-质谱 苯多羧酸 硝基苯多羧酸 溶解
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光场作用下特殊势阱模型中的量子隧穿抑制和其物理解释
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作者 毕冬艳 李永放 《量子光学学报》 CSCD 北大核心 2007年第4期308-312,共5页
当一个单独的分子被镶嵌在一个主体的媒质中时,外加的激光场可以使其中的隧道效应被抑制。外场作用时,形成Λ型三能级系统,通过缀饰分析法、黑态明态分析法和一些近似,得出结论。明黑态的分析乃是对这一特殊系统发生相干隧穿抑制现象的... 当一个单独的分子被镶嵌在一个主体的媒质中时,外加的激光场可以使其中的隧道效应被抑制。外场作用时,形成Λ型三能级系统,通过缀饰分析法、黑态明态分析法和一些近似,得出结论。明黑态的分析乃是对这一特殊系统发生相干隧穿抑制现象的一种物理解释。在一定的情况下粒子不但可以被定域在各自所处的阱里,而且可以完全定域在较低的势阱里。 展开更多
关键词 相干隧穿抑制 A型三能级系统 黑态 缀饰
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海洋溶解态黑碳的研究进展 被引量:6
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作者 黄国培 陈颖军 +4 位作者 田崇国 唐建辉 潘晓辉 王艳 李军 《地球科学进展》 CAS CSCD 北大核心 2012年第12期1326-1336,共11页
溶解态黑碳(DBC)作为黑碳(BC)降解的中间产物,是海洋溶解有机碳碳库的重要组分,涉及全球海洋碳收支并进一步影响全球气候变化;是有色溶解有机质的重要组分,可改变水体光学环境从而对生态系统产生影响;也是一类良好的有机配体,在环境中... 溶解态黑碳(DBC)作为黑碳(BC)降解的中间产物,是海洋溶解有机碳碳库的重要组分,涉及全球海洋碳收支并进一步影响全球气候变化;是有色溶解有机质的重要组分,可改变水体光学环境从而对生态系统产生影响;也是一类良好的有机配体,在环境中易与金属离子形成络合物从而影响金属污染物的行为与毒性。鉴于其在气候变化、生态和环境等方面的重要影响,近年来研究者越来越关注DBC,并取得了一些基础性成果。目前,在DBC的定性认识上还存在一些模糊区域,所以DBC还没有一个明确的定义,DBC只是一个术语,特指一类由浓缩稠环母体和亲水性取代基(主要为羧基)组成的复杂有机物。在DBC的来源方面,已有证据证明BC降解能够产生DBC;但DBC很可能还存在其他来源,仍需进一步研究确认。DBC主要随水体进行迁移,并已观察到了DBC的降解现象,但目前对DBC的降解机理及速率仍不了解。在定量分析方法上,由于DBC的极性很强,且与其共存的基质相当复杂,分析DBC具有很大的挑战,其中苯多羧酸分子标志物法(BPCA)是定量分析DBC很有前景的方法之一,但目前仍存在一些难点需要解决。DBC在全球不同水体中含量变化很大,但目前的数据相当有限,不足以全面评估DBC的储量和循环周期。从DBC的定性识别、来源、迁移转化、定量分析及含量分布等方面综述DBC的研究进展,重点讨论BPCA法定量DBC的研究现状及存在问题,并展望DBC的研究方向。 展开更多
关键词 溶解 分子结构 定量方法 苯多羧酸
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Comparative study on three dynamic modulus of elasticity and static modulus of elasticity for Lodgepole pine lumber 被引量:5
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作者 梁善庆 傅峰 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期309-312,共4页
The dynamic and static modulus of elasticity (MOE) between bluestained and non-bluestained lumber of Lodgepole pine were tested and analyzed by using three methods of Non-destructive testing (NDT), Portable Ultras... The dynamic and static modulus of elasticity (MOE) between bluestained and non-bluestained lumber of Lodgepole pine were tested and analyzed by using three methods of Non-destructive testing (NDT), Portable Ultrasonic Non-destructive Digital Indicating Testing (Pundit), Metriguard and Fast Fourier Transform (FFT) and the normal bending method. Results showed that the dynamic and static MOE of bluestained wood were higher than those of non-bluestained wood. The significant differences in dynamic MOE and static MOE were found between bulestained and non-bluestained wood, of which, the difference in each of three dynamic MOE (Ep. the ultrasonic wave modulus of elasticity, Ems, the stress wave modulus of elasticity and El, the longitudinal wave modulus of elasticity) between bulestained and non-bluestained wood arrived at the 0.01 significance level, whereas that in the static MOE at the 0.05 significance level. The differences in MOE between bulestained and non-bluestained wood were induced by the variation between sapwood and heartwood and the different densities of bulestained and non-bluestained wood. The correlation between dynamic MOE and static MOE was statistically significant at the 0.01 significance level. Although the dynamic MOE values of Ep, Em, Er were significantly different, there exists a close relationship between them (arriving at the 0.01 correlation level). Comparative analysis among the three techniques indicated that the accurateness of FFT was higher than that of Pundit and Metriguard. Effect of tree knots on MOE was also investigated. Result showed that the dynamic and static MOE gradually decreased with the increase of knot number, indicating that knot number had significant effect on MOE value. 展开更多
关键词 Lodgepole pine Non-destructive testing Dynamic modulus of elasticity Static modulus of elasticity
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Wintering ecology of the Black Stork (Ciconia nigra) in Beijing 被引量:1
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作者 李晓京 史洋 +1 位作者 徐基良 鲍伟东 《Chinese Birds》 2011年第1期46-52,共7页
The Black Stork (Ciconia nigra) is a new winter resident in Beijing due to temperature changes.To understand the wintering ecology of this species better, a field survey covering the number of birds of this population... The Black Stork (Ciconia nigra) is a new winter resident in Beijing due to temperature changes.To understand the wintering ecology of this species better, a field survey covering the number of birds of this population, habitat selection, feeding activity and grouping behavior was conducted at the Shidu Nature Reserve from January 2004 to March 2009. The results show that the Black Stork selected the Juma River at this nature reserve as their new winter habitat. The number of birds in this population decreased from 28 in the 2004/2005 winter to 17 in the 2007/2008 winter with a subsequent recovery to 23 the following year. The wintering flock was formed in mid-November and dispersed in mid-March, but the date changed with seasonal temperature fluctuations. The storks exhibited feeding habitat fidelity and the main food type was fish (> 92.4%). There was no significant variation in food composition between adults and sub-adults (Mann-Whitney U test, U = 1.00, p = 0.44). Feeding activity occurred in the morning and at noon during early winter, but concentrated in the afternoon during mid winter, divided into dawn and dusk in late winter. Daily fish intake was 538 g for adults and 449 g for sub-adults if the period of foraging reached six hours in the wild, which was similar to the level under artificial feeding. Agonistic behavior among feeding birds was observed among group members in late winter. The main negative factor for wintering Black Stork was a reduced feeding habitat resulting from increased water depth due to damming of the river to benefit tourism and to wetland exploitation. 展开更多
关键词 BEIJING Ciconia nigra foraging behavior wintering ecology
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浅析TN/IPS显示模式的液晶屏在机载显示中的应用
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作者 卢业能 《中国新技术新产品》 2021年第1期16-19,共4页
该文基于TN/IPS显示模式的基本特点,结合机载显示在特殊环境下的应用需求,重点分析了2种显示模式在黑背景显示、宽温工作、宽温贮存以及、高强度振动要求下的性能差异。TN/IPS 2种显示模式的液晶屏经过加固设计后均可以应用于机载显示,... 该文基于TN/IPS显示模式的基本特点,结合机载显示在特殊环境下的应用需求,重点分析了2种显示模式在黑背景显示、宽温工作、宽温贮存以及、高强度振动要求下的性能差异。TN/IPS 2种显示模式的液晶屏经过加固设计后均可以应用于机载显示,IPS显示模式液晶屏的综合黑态显示效果及抗振动性能优于TN显示模式,更适合在机载显示加固中应用。 展开更多
关键词 机载显示 黑态显示 高强度振动
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溶解态黑碳的环境过程研究 被引量:7
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作者 魏晨辉 付翯云 +1 位作者 瞿晓磊 朱东强 《化学进展》 SCIE CAS CSCD 北大核心 2017年第9期1042-1052,共11页
溶解态黑碳是黑碳连续体中可溶解于水的组分,是连接陆地土壤和海洋底泥两个主要黑碳库的关键纽带。溶解态黑碳也是天然可溶性有机质的重要组分,富含芳香微域结构和羧基、羟基、羰基等功能性官能团,具有较高的反应活性,可介导污染物在环... 溶解态黑碳是黑碳连续体中可溶解于水的组分,是连接陆地土壤和海洋底泥两个主要黑碳库的关键纽带。溶解态黑碳也是天然可溶性有机质的重要组分,富含芳香微域结构和羧基、羟基、羰基等功能性官能团,具有较高的反应活性,可介导污染物在环境中的分配和转化过程。因此,研究溶解态黑碳的环境地球化学行为对研究全球碳循环以及污染物的环境归趋和效应都具有重要意义,已成为了相关领域的前沿和热点。本文综述了十余年以来溶解态黑碳在环境过程方面的研究进展,重点阐述了溶解态黑碳的定性、定量分析方法,在环境中的含量和空间分布、结构特征、环境转化过程,以及其对污染物吸附、氧化还原转化、光转化等环境行为的影响,并在此基础上对溶解态黑碳的未来研究方向进行了展望。 展开更多
关键词 溶解 时空分布 结构特征 污染物环境效应 作用机制
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Genetic Polymorphism of Ten Microsatellites in Two Goat Breeds and Its Relationship with Heterosis
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作者 李晓锋 马月辉 +4 位作者 熊琪 索效军 张年 杨前平 陈明新 《Agricultural Science & Technology》 CAS 2013年第8期1078-1084,共7页
[Objective] This study aimed to investigate the genetic diversity of Macheng black goat and its correlation with heterosis.[Method] Ten microsatellite markers were selected for polymorphism investigation and statistic... [Objective] This study aimed to investigate the genetic diversity of Macheng black goat and its correlation with heterosis.[Method] Ten microsatellite markers were selected for polymorphism investigation and statistical analysis of Boer goat and Macheng black goat populations.[Result] The results showed that totally 175 alleles were found in 10 microsatellite loci; to be specific,the maximum number of detected alleles was 23,and the minimum number was 10; the effective number of alleles (Ne) was 6.4-18.1,with absolute difference value of 1.6-8.1 from the observed number of alleles.The highest gene frequency was 0.239 1 and the lowest was 0.002 7.The polymorphic information contents of all the ten microsatellite markers were above 0.95.The observed heterozygosity (Ho) ranged from 0.616 7 to 0.984 4 and the expected heterozygosity (He) ranged from 0.844 1 to 0.944 6.The average expected heterozygosity of Boer goat and Macheng black goat was respectively 0.894 0 and 0.906 7.Various body weight and body size indices of Boer goatxMacheng black goat hybrids were improved in varying degrees compared with Macheng black goat (with an increase range of 0.32%-30.06%).The average heterosis rates of body height and chest girth were relatively high,while average heterosis rate of body weight was relatively low.[Conclusion] The genetic distance between Boer goat and Macheng black goat was 0.379 5,which is consistent with the geographical distribution of Boer goat and Macheng black goat populations and is fully relevant to the heterosis of Boer goat × Macheng black goat hybrids,indicating that investigating polymorphism via microsatellite loci is one of the feasible means to predict and analyze heterosis between varieties. 展开更多
关键词 Microsatellite marker Genetic polymorphism Boer goat Macheng blackgoat HETEROSIS
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Infection of the Anther-smut Microbotryum violaceum in Populations of Silene dioica: Variation in Floral Morphology, Patterns of Spore Deposition and Pathogen-Pollinator Mediated Selection
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作者 刘登义 Ulla CARLSSON 《Acta Botanica Sinica》 CSCD 2002年第1期88-96,共9页
The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dis... The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dispersal propagules) in flowers. These spores are transmitted to healthy plants mainly by flower visitors. The behavioral responses of flower visitors to a variation in floral characters are not only likely to affect rates of pollen export/import, but also the rate of spore deposition and probability of disease. In a transplantation experiment, using plants from four different populations, we tested for correlation between variation in female floral morphology and patterns of spore and pollen deposition, and a resulting risk of disease. The source populations in this experiment were located on four islands in Skeppsvik archipelago in northern Sweden, and represented a gradient of disease incidence from completely healthy ( Island 1), low incidence ( Island 2) to high incidences ( Islands 3 and 4) of disease. Fifty plants from each population were transplanted to the center, of the population on Island 4. There were significant differences among the transplants in floral characters, i.e. corolla size, style length and ovule number. Plants from the non-diseased population had larger flowers and longer styles than plants from the highly diseased populations. Numbers of pollen grains and spores deposited on flowers were strongly and positively correlated. We found that plants originating from the non-diseased population captured approximately 4 times more pollen and 9 times more spores, per flower than die individuals from the resident population (Island 4, population 4). The incidences of disease among plants, from the four populations differed significantly, and was 37%, 20%, 18% and 0 for populations 1, 2, 3 and 4 respectively. In a survey of ten populations we found a significant negative correlation between the mean style length ( positively correlated with corolla size and ovule number) among healthy plants and incidence of disease in these populations. The potentiality for pathogen-pollinator mediated selection oil floral characters; and consequences for gone flow between populations of Silene dioica are discussed. 展开更多
关键词 Silene dioica floral morphology anther-smut infection patterns of spore deposition pathogen-pollinator mediated selection
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Comparison of Morphological Microstructure of Vitrified and Normal Shoots of Aronia melanocarpa Elloit 被引量:2
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作者 高晔华 利爽 +2 位作者 吕天舒 胡婷婷 吴荣哲 《Agricultural Science & Technology》 CAS 2014年第10期1667-1670,1683,共5页
The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-... The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken. 展开更多
关键词 Aronia melanocarpa El oit Morphological microstructure Normal shoot Vitrified shoot
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Implementing a Universal Quantum Cloning Machine via Adiabatic Evolution in Ion-Trap System
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作者 YANG Rong-Can LI Hong-Cai LIN Xiu HUANG Zhi-Ping XIE Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期80-82,共3页
A scheme for the realization of a universal quantum cloning machine is proposed in this paper. The present protocol does not need the vibrational mode to act as the memory and it is robust against small changes of exp... A scheme for the realization of a universal quantum cloning machine is proposed in this paper. The present protocol does not need the vibrational mode to act as the memory and it is robust against small changes of experimental parameters due to adiabatic passages. Furthermore, the scheme may be realized based on current technology. 展开更多
关键词 universal quantum cloning adiabatic evolution dark state trapped ions
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Immunohistochemical evaluation of vitamin D receptor(VDR) expression in cutaneous melanoma tissues and four VDR gene polymorphisms 被引量:5
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作者 Francesco La Marra Giuseppe Stinco +4 位作者 Cinzia Buligan Giovanni Chiriacò Diego Serraino Carla Di Loreto Sabina Cauci 《Cancer Biology & Medicine》 SCIE CAS CSCD 2017年第2期162-175,共14页
Objective:Vitamin D receptor(VDR)mediates vitamin D activity.We examined whether VDR expression in excised melanoma tissues is associated with VDR gene(VDR)polymorphisms.Methods:We evaluated VDR protein expression(by ... Objective:Vitamin D receptor(VDR)mediates vitamin D activity.We examined whether VDR expression in excised melanoma tissues is associated with VDR gene(VDR)polymorphisms.Methods:We evaluated VDR protein expression(by monoclonal antibody immunostaining),melanoma characteristics,and carriage of VDR-Fok I-rs2228570(C>T),VDR-Bsm I-rs1544410(G>A),VDR-ApaI-rs7975232(T>G),and VDR-TaqI-rs731236(T>C)polymorphisms(by restriction fragment length polymorphism).Absence or presence of restriction site was denoted by a capital or lower letter,respectively:"F"and"f"for Fok I,"B"and"b"for Bsm I,"A"and"a"for ApaI,and "T"and"t"for TaqI endonuclease.Seventy-four Italian cutaneous primary melanomas(52.1±12.7 years old)were studied;51.4% were stage Ⅰ,21.6% stage Ⅱ ,13.5% stage Ⅲ,and 13.5% stage Ⅳ melanomas.VDR expression was categorized as follows:100% positive vs.<100%;over the median 20%(high VDR expression)vs.≤20%(low VDR expression);absence vs.presence of VDR-expressing cells.Results:Stage I melanomas,Breslow thickness of<1.00 mm,level II Clark invasion,Aa heterozygous genotype,and AaTT combined genotype were more frequent in melanomas with high vs.low VDR expression.Combined genotypes BbAA,bbAa,AATt,BbAATt,and bbAaTT were more frequent in 100%vs.<100%VDR-expressing cells.Combined genotype AATT was more frequent in melanomas lacking VDR expression(odds ratio=14.5;P=0.025).VDR expression was not associated with metastasis,ulceration,mitosis>1,regression,tumor-infiltrating lymphocytes,tumoral infiltration of vascular tissues,additional skin and non-skin cancers,and melanoma familiarity.Conclusions:We highlighted that VDR polymorphisms can affect VDR expression in excised melanoma cells.Low VDR expression in AATT carriers is a new finding that merits further study.VDR expression possibly poses implications for vitamin D supplementation against melanoma.VDR expression and VDR genotype may become precise medicinal tools for melanoma in the future. 展开更多
关键词 Vitamin D receptor VDR protein expression VDR polymorphism cutaneous melanoma metastatic melanoma skin cancer predictive biomarkers FokI polymorphism
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