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凌霄花红色素的提取及稳定性研究

新乡医学院学报 1998年第4期15卷 330-332页

作者：王改萍胡雪原阎福林刘晓红新乡医学院化学教研室滑县二中

目的研究凌霄花红色素的提取方法及其稳定性，为开发利用天然色素提供依据。方法室温下，用酸性乙醇浸泡新鲜凌霄花，过滤得色素提取液，然后对该色素的耐酸碱性、耐热性、耐光性、耐氧化还原性等理化性质进行测定和分析。结果此色素为... 详细信息

目的研究凌霄花红色素的提取方法及其稳定性，为开发利用天然色素提供依据。方法室温下，用酸性乙醇浸泡新鲜凌霄花，过滤得色素提取液，然后对该色素的耐酸碱性、耐热性、耐光性、耐氧化还原性等理化性质进行测定和分析。结果此色素为水溶性食用色素，其耐热性、耐光性较好，在酸性介质，还原剂、食品添加剂对色素的色泽无不良影响。结论该色素是一种可广泛应用于食品、饮料、医药等行业，且具有药用价值的天然植物色素。

关键词：食用色素凌霄花红色素提取稳定性

Pine wilt disease in Yunnan, China： Evidence of non-local pine sawyer Monochamus alternatus （Coleoptera： Cerambycidae） populations revealed by mitochondrial DNA

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Insect Science 2010年第5期17卷 439-447页

作者： Da-Ying Fu Shao-Ji hu hui Ye Robert A. Haack ping-Yang Zhou School of Life Sciences Yunnan University Kunming China USDA Forest Service Northern Research Station 1407 South Harrison Road East Lansing MI 48823 USA Forest Diseases and Pest Control ancl Quarantine Station of Dehong Prefecture Luxi Yunnan Province China

Monochamus alternatus （Hope） specimens were collected from nine geographical populations in China, where the pinewood nematode Bursaphelenchus xylophilus （Steiner et Buhrer） was present. There were seven populations in southwestern China in Yunnan Province （Ruili, Wanding, Lianghe, Pu＇er, huaning, Stone Forest and Yongsheng）, one in central China in hubei Province （Wuhan）, and one in eastern China in Zhejiang Province （Hangzhou）. Twenty-two polymorphic sites were recognized and 18 haplotypes were established by analyzing a 565 bp gene fragment of mitochondrial cytochrome oxidase subunit II （CO II）. Kimura two-parameter distances demonstrated that M. alternatus populations in Ruili, Wanding and Lianghe （in southwestern Yunnan） differed from the other four Yunnan populations but were similar to the Zhejiang population. No close relationship was found between the M. alternatus populations in Yunnan and hubei. Phylogenetic reconstruction established a neighbor-joining （N J） tree, which divided haplotypes of southwestern Yunnan and the rest of Yunnan into different clades with considerable bootstrapping values. Analysis of molecular variance and spatial analysis of molecular variance also suggested significant genetic differentiation between M. alternatus populations in southwestern Yunnan and the rest of Yunnan. Our research suggests that non-local populations of M. alternates, possibly from eastern China, have become established in southwestern Yunnan. Key words mitochondrial DNA, non-local vector, pine wilt disease

关键词： mitochondrial DNA non-local vector pine wilt disease

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东胜矿区浅埋煤层区段煤柱宽度优化设计

煤炭技术 2023年第12期42卷 56-60页

作者：胡平孙爱东温国惠朱建平连平小段会强唐共龙戴永帅史振杨超常超内蒙古双欣矿业有限公司内蒙古鄂尔多斯017001 内蒙古科技大学矿业与煤炭学院内蒙古包头014010

针对东胜矿区煤矿开采过程中区段煤柱宽度过大造成资源浪费问题,以双欣矿业4107工作面为工程背景,通过理论计算、数值模拟和现场工程实践等方法对合理的区段煤柱宽度进行了研究。理论计算得出合理的区段煤柱宽度为9.05~10.62 m。数值模... 详细信息

针对东胜矿区煤矿开采过程中区段煤柱宽度过大造成资源浪费问题,以双欣矿业4107工作面为工程背景,通过理论计算、数值模拟和现场工程实践等方法对合理的区段煤柱宽度进行了研究。理论计算得出合理的区段煤柱宽度为9.05~10.62 m。数值模拟结果表明:工作面回采后,在距采空区边缘9.5 m的位置,煤层及顶底板中的垂直应力在6.15 MPa左右,应力集中系数为1.17,仅略高于原岩应力;当区段煤柱宽度为10 m时,作用在区段煤柱上的垂直应力呈“马鞍形”分布特征,证明煤柱中间存在弹性核区,煤柱能够保持稳定。现场实践表明,当区段煤柱宽度为10 m时,巷道顶板离层最大为11 mm,两帮移近量最大为101 mm,采动应力对巷道围岩变形的明显影响范围不超过22 m。

关键词：区段煤柱合理宽度垂直应力分布围岩变形

表面麻醉下穿透性角膜移植术治疗角膜穿孔伤的研究

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眼外伤职业眼病杂志 2009年第12期31卷 881-883页

作者：吴护平谢素贞李晓峰康克明何雪洪厦门大学附属厦门眼科中心福建厦门361001

目的探讨表面麻醉下行穿透性角膜移植手术(PKP)治疗角膜穿孔伤的可行性。方法回顾性分析10例(10眼)在表面麻醉下行PKP治疗角膜穿孔伤的临床资料。结果所有患者均能耐受和配合手术,8例术后视力均得到不同程度的提高。术后植片透明7例,透... 详细信息

目的探讨表面麻醉下行穿透性角膜移植手术(PKP)治疗角膜穿孔伤的可行性。方法回顾性分析10例(10眼)在表面麻醉下行PKP治疗角膜穿孔伤的临床资料。结果所有患者均能耐受和配合手术,8例术后视力均得到不同程度的提高。术后植片透明7例,透明率为70.00%,其中1例甘油冷冻保存的角膜术后植片浑浊,1例因排斥反应导致植片浑浊,另1例因继发性青光眼后角膜失代偿导致植片浑浊。结论表面麻醉下行PKP是治疗角膜穿孔伤的一种安全有效的方法。

关键词：角膜移植术表面麻醉角膜穿孔

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儿童贴纸书抗弯曲性能影响因素研究

广州化工 2017年第15期45卷 98-100页

作者：吕卓朋劳雪金冯庆民蒋颜平胡剑青鹤山雅图仕印刷有限公司广东江门529738 广东星宇耐力新材料股份有限公司广东东莞523270 华南理工大学化学与化工学院广东广州510640

通过合成丙烯酸酯压敏标签胶,研究胶黏剂玻璃化温度(Tg)和功能单体丙烯酸的用量以及不同面材和底材的吸水性、储存环境对儿童贴纸书抗弯曲性能的影响。结果表明,底材吸水量在29.5 g/m^2左右时,使用纸张纤维致密的铜版纸制备的贴纸书抗... 详细信息

通过合成丙烯酸酯压敏标签胶,研究胶黏剂玻璃化温度(Tg)和功能单体丙烯酸的用量以及不同面材和底材的吸水性、储存环境对儿童贴纸书抗弯曲性能的影响。结果表明,底材吸水量在29.5 g/m^2左右时,使用纸张纤维致密的铜版纸制备的贴纸书抗弯曲性能较好;面材和胶黏剂对抗弯曲性能影响不明显;此外,研究发现后放置环境条件选用温度(23±3)℃,湿度50%±5%的标准条件下,儿童贴纸书的弯曲变形度最小。

关键词：儿童贴纸书抗弯曲性能吸水量胶黏剂后处理条件

Removing the remaining ridges in fingerprint segmentation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第6期7卷 976-983页

作者： Zhu En ZHANG Jian-ming YIN Jian-ping ZHANG Guo-min hu Chun-feng School of Computer Science National University of Defense Technologp. Changsha 410073 China Department of Computer Sctence Hunan City University Yiyang 413049 China College of Computer and Communication Hunan University Changsha 410082 China

Fingerprint segmentation is an important step in fingerprint recognition and is usually aimed to identify non-ridge regions and unrecoverable low quality ridge regions and exclude them as background so as to reduce the time expenditure of image processing and avoid detecting false features. In high and in low quality ridge regions, often are some remaining ridges which are the afterimages of the previously scanned finger and are expected to be excluded from the foreground. However, existing seg-mentation methods generally do not take the case into consideration, and often, the remaining ridge regions are falsely classified as foreground by segmentation algorithm with spurious features produced erroneously including unrecoverable regions as fore-ground. This paper proposes two steps for fingerprint segmentation aimed at removing the remaining ridge region from the fore-ground. The non-ridge regions and unrecoverable low quality ridge regions are removed as background in the first step, and then the foreground produced by the first step is further analyzed for possible remove of the remaining ridge region. The proposed method proved effective in avoiding detecting false ridges and in improving minutiae detection.

关键词： Fingerprint segmentation Recoverable ridges Remaining ridges

基于混合交叉算子改进NSGA-Ⅱ算法的董铺—大房郢水库优化调度研究

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水电能源科学 2025年第1期43卷 197-201页

作者：陈虎郭园祝雪萍霍云超刘晓东高学睿牛鑫太原理工大学水利科学与工程学院山西太原030024 中国电建集团西北勘测设计研究院有限公司陕西西安710065 西北农林科技大学水土保持研究所陕西杨凌712100

以安徽省董铺—大房郢水库为例,以水库缺水率最小和补水量最少为最优准则,考虑董铺—大房郢水库水源连通工程水量补偿式调节和接受上游淠河灌区水库群补水的特殊机制,构建董铺—大房郢水库双目标优化供水调度模型,并采用基于混合交叉算... 详细信息

以安徽省董铺—大房郢水库为例,以水库缺水率最小和补水量最少为最优准则,考虑董铺—大房郢水库水源连通工程水量补偿式调节和接受上游淠河灌区水库群补水的特殊机制,构建董铺—大房郢水库双目标优化供水调度模型,并采用基于混合交叉算子改进的NSGA-Ⅱ算法求解模型。结果表明,算数交叉算子(ACO)混合模拟二进制交叉算子(SBX)的收敛时间较单一SBX算子缩短11.48%,较单一ACO算子缩短2.58%;其中混合算子SBX-ACO求得的解集质量更好,对应评价指标世代距离(GD)值(8.13×10^(-4))、反世代距离(IGD)值(3.1×10^(-4))为所有计算方案中最小。优化调度模型求解的供水方案中两库补水量比不优化条件下的补水量减少11.5%。在计算效率及解集质量上综合验证了所提出的改进算法的有效性,同时为区域水资源优化调度提供科学依据。

关键词：改进NSGA-Ⅱ 混合交叉算子优化供水调度 IGD评价指标

平台式重力仪航空重力测量数据后处理技术研究

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导航定位与授时 2019年第3期6卷 52-61页

作者：闫方胡平华赵明姜作喜罗锋唐江河刘东斌北京自动化控制设备研究所中国国土资源航空物探遥感中心

针对航空重力测量对数据后处理的要求,结合平台式重力仪系统的组成与工作原理,在重力异常信号的频域特征基础上,设计出一套有严格频域规范的航空重力数据后处理流程,并对某海域实测数据进行了处理。结果表明,重力异常值内符合精度为12... 详细信息

针对航空重力测量对数据后处理的要求,结合平台式重力仪系统的组成与工作原理,在重力异常信号的频域特征基础上,设计出一套有严格频域规范的航空重力数据后处理流程,并对某海域实测数据进行了处理。结果表明,重力异常值内符合精度为12条东西测线达到0.43mGal/140s和0.84mGal/100s,4条南北测线达到0.39mGal/140s和0.79mGal/100s;以同测线GT-2A单次测量结果为标准值统计标准差,12条东西测线为0.72mGal/140s和0.98mGal/100s,4条南北测线为1.41mGal/140s和1.53mGal/100s。结果表明,设计的航空重力测量数据后处理方法可以实现重力异常信号的高精度提取。

关键词：平台式重力仪航空重力测量重力数据后处理 FIR滤波

Crystallization and inter-diffusional behaviors in the formation of VO2(B) thin film with layered W-doping

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Journal of Advanced Ceramics 2017年第3期6卷 196-206页

作者： Chuanshuo ZHANG Dongli hu hui GU Juanjuan XING ping XIONG Dongyun WAN Yanfeng GAO School of Materials Science and Engineering Shanghai University Shanghai 200444 China School of Materials Science and Engineering Shanghai University Shanghai 200444 ChinaMaterials Genome Institute Shanghai University Shanghai 200444 China

To achieve a better material for uncooled infrared (IR) detector, polycrystalline VO2(B) thin films with layered W-doping were fabricated on Si substrates by magnetron sputtering, and the best temperature coefficient of resistance (TCR) value reached -4.1%/K. The film synthesis was in a two-step route, first deposition at room temperature and then post-deposition annealing at 450 ℃, to better control the crystallization behavior. Various transmission electron microscopy (TEM) methods were employed to investigate three sets of multi-layered films with different deposition time, 10, 20, and 30 min, with especial emphasis on the effect of layered W-doping scheme on the formation of multiple VO2(B) layers. Spatial-resolved energy dispersive X-ray spectroscopy (EDS) revealed the alternative patterns of W-rich layers and W-poor layers, while the thinner films exhibited better crystallinity and texturing. By comparison with an as-deposited film, it was found that the inter-diffusion between the two types of layers was completed in the deposition step while both remained in amorphous structure. A stable W solution of about 8 cat% in VO2(B) layers measured from all these films indicated that the layered doping can tailor the multi-layered microstructure to optimize the performance of VO2(B) films.

关键词： VO2(B) thin film layered W-doping crystallization transmission electron microscopy (TEM) solid-solution