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Improved Microfluidic Coupled-Cavity Waveguides for Slow Light Transmission

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Chinese Physics Letters 2010年第3期27卷 166-169页

作者：吕淑媛赵建林张栋 Institute of Optical Information Science and Technology Shanxi Key Laboratory of Optical Information Technology School of Science Northwestern Polytechnical University Xi'an 710072

We present a method based on the selective liquid infiltration in air holes to produce slow light in a coupled-cavity waveguide structured by two-dimensional photonic crystal and analyze the slow light propagation in the coupled-cavity waveguide with triangular lattice. The group velocity profile of different coupled-cavity waveguides, obtained by the selective liquid infiltration in the holes between the cavities in waveguide and the increased radius of the first row of holes adjacent to the waveguide, is evaluated by using both the plane-wave expansion method and a tight binding model. We determine the optimal parameters to reduce the group velocity. Using a simpler coupled-cavity waveguide structure we obtain smaller group velocity compared to most investigations.

关键词： Electronics and devices Optics quantum optics and lasers Nanoscale science and low-D systems

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基于核方法的聚类算法及其应用

北京航空航天大学学报 2006年第6期32卷 747-750页

作者：纪秋颖林健五邑大学管理学院江门529020 北京航空航天大学经济管理学院北京100083

在分析核方法的核心概念基础上,提出了一种基于核方法的聚类算法.通常,传统聚类算法只在数据特征差异较大时才有效,当数据特征差异较小时,很难取得较好的聚类效果.引入核函数,将原始数据由数据空间映射到特征空间,在特征空间中进行聚类... 详细信息

在分析核方法的核心概念基础上,提出了一种基于核方法的聚类算法.通常,传统聚类算法只在数据特征差异较大时才有效,当数据特征差异较小时,很难取得较好的聚类效果.引入核函数,将原始数据由数据空间映射到特征空间,在特征空间中进行聚类.核函数的非线性映射使得原始数据的特征更完整地显现出来,从而能够更客观准确地聚类.与传统聚类方法相比,该方法聚类结果更客观有效.以16组实际数据为例,将该方法应用于数据分类研究中,聚类结果表明了该方法的可行性和有效性,从而为数据分类提供了一种新的可行方法.

关键词：聚类算法核方法特征空间核函数分类

混杂纤维层数对再生混凝土力学性能的影响研究

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合成纤维 2024年第8期53卷 68-71,79页

作者：浦健民史晓东王胜辉王鹏王广哲中建安装集团有限公司山东济南250000

为改善再生混凝土的强度和韧性,采用质量分数为12%的粉煤灰代替部分水泥,并以占总质量百分比为28%的再生粗骨料代替部分天然粗骨料配制的再生混凝土作为基准组,以此进行不同层数混掺纤维的再生混凝土试验。研究结果表明:增加混杂纤维的... 详细信息

为改善再生混凝土的强度和韧性,采用质量分数为12%的粉煤灰代替部分水泥,并以占总质量百分比为28%的再生粗骨料代替部分天然粗骨料配制的再生混凝土作为基准组,以此进行不同层数混掺纤维的再生混凝土试验。研究结果表明:增加混杂纤维的撒布层数能够提升再生混凝土的抗压强度,但提升的程度有限;当混杂纤维层数为2层时,能够使混凝土的劈裂抗拉强度显著增加;随着混杂纤维层数的不断增加,再生混凝土的拉压比表现出先增大后减小的变化趋势,弹强比则先减小后增大趋势;再生混凝土力学指标均处于良好状态的最佳纤维撒布层数为4层。

关键词：混杂纤维层数再生混凝土抗压强度拉压比力学性能

Downregulation of miR-491-5p promotes neovascularization after traumatic brain injury

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Neural Regeneration Research 2022年第3期17卷 577-586页

作者： Wei Tang Zong-Duo Guo Wei-Na Chai dong-Lin Du Xiao-Min Yang Lang Cao Hong Chen Chao Zhou Chong-jie Cheng Xiao-Chuan Sun Zhi-jian Huang jian-Jun Zhong Department of Neurosurgery First Affiliated Hospital of Chongqing Medical UniversityChongqingChina Department of Ophthalmology First Affiliated Hospital of Chongqing Medical UniversityChongqingChina

Micro RNA-491-5 p(miR-491-5 p) plays an important role in regulating cell proliferation and migration;however,the effect of miR-491-5 p on neovascularization after traumatic brain injury remains poorly *** this study,a controlled cortical injury model in C57 BL/6 mice and an oxygen-glucose deprivation model in microvascular endothelial cells derived from mouse brain were established to simulate traumatic brain injury in vivo and in vitro,*** the in vivo model,quantitative real-time-polymerase chain reaction results showed that the expression of miR-491-5 p increased or decreased following the intracerebroventricular injection of an miR-491-5 p agomir or antagomir,respectively,and the expression of miR-491-5 p decreased slightly after traumatic brain *** detect the neuroprotective effects of miR-491-p,neurological severity scores,Morris water maze test,laser speckle techniques,and immunofluorescence staining were assessed,and the results revealed that miR-491-5 p downregulation alleviated neurological dysfunction,promoted the recovery of regional cerebral blood flow,increased the number of lectin-stained microvessels,and increased the survival of neurons after traumatic brain *** the in vitro experiments,the potential mechanism of miR-491-5 p on neovascularization was explored through quantitative real-time-polymerase chain reaction,which showed that miR-491-5 p expression increased or decreased in brain microvascular endothelial cells after transfection with an miR-491-5 p mimic or inhibitor,***-luciferase reporter and western blot assays verified that metallothionein-2 was a target gene for miR-491-5 *** counting kit 8(CCK-8) assay,flow cytometry,and 2′,7′-dichlorofluorescein diacetate(DCFH-DA) assay results confirmed that the downregulation of miR-491-5 p increased brain microvascular endothelial cell viability,reduced cell apoptosis,and alleviated oxidative stress under oxygen-glucose deprivation conditions.C

关键词： brain injury cell migration cell proliferation endothelial cell hypoxia-inducible factor-1 alpha metallothionein 2 microRNA neovascularization neurons vascular endothelial growth factor

Electrodes with Electrodeposited Water-excluding Polymer Coating Enable High-Voltage Aqueous Supercapacitors

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Research 2020年第1期2020卷 711-723页

作者： Wujie dong Tianquan Lin jian Huang Yuan Wang Zhichao Zhang Xin Wang Xiaotao Yuan jie Lin I-Wei Chen Fuqiang Huang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Department of Materials Science and Engineering University of PennsylvaniaPhiladelphiaPA 19104USA

Aqueous supercapacitors are powerful energy sources,but they are limited by energy density that is much lower than lithium-ion *** raising the voltage beyond the thermodynamic potential for water splitting(1.23 V)can boost the energy density,there has been much effort on water-stabilizing salvation additives such as Li_(2)SO_(4) that can provide an aqueous electrolyte capable of withstanding~1.8 *** by the first-principles calculations that reveal water can promote hydrogen and oxygen evolution reactions,here,we pursue a new strategy of covering the electrode with a dense electroplated polymerized polyacrylic acid,which is an electron insulator but a proton conductor and proton *** combined effect of salvation and coating expands the electrochemical window throughout pH 3 to pH 10 to 2.4V for both fast and slow proton-mediated redox *** allows activated carbon to quadruple the energy density,a kilogram of nitrogen-doped graphene to provide 127 Watt-hour,and both to have improved endurance because of suppression of water-mediated ***,aqueous supercapacitors can now achieve energy densities quite comparable to that of a lithium-ion battery,but at 100 times the charging/discharging speed and cycle durability.

关键词： lithium durability battery

Coupling relationship between reservoir diagenesis and hydrocarbon accumulation in Lower Cretaceous Yingcheng Formation of dongling,Changling fault depression,Songliao Basin,Northeast China

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China Geology 2020年第2期3卷 247-261页

作者： Yun-qian Lu You-lu jiang Wei Wang jian-feng Du jing-dong Liu Guangzhou Marine Geological Survey China Geological SurveyMinistry of Natural ResourcesGuangzhou 510075China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China School of Geosciences China University of PetroleumQingdao 266580China Sinopec Northeast Oil-Gas Branch Company Changchun 130062China

The Lower Cretaceous Yingcheng Formation in the southern Songliao Basin is the typical tight oil sandstone in *** order to better predict the petrophysical properties of the tight sandstone reservoirs in the Lower Cretaceous Yingcheng Formation,Songliao Basin,Northeast China,the diagenesis and porosity evolution was investigated using a suite of petrographic and geochemical techniques including thin section analysis,scanning electron microscopy,mercury intrusion and fluid inclusion analysis,on a set of selected tight sandstone *** with the histories of burial evolution,organic matter thermal evolution and hydrocarbon charge,the matching relationship between reservoir porosity evolution and hydrocarbon accumulation history is *** result showed that the tight sandstone reservoirs characterized of being controlled by deposition,predominated by compaction,improved by dissolution and enhanced by *** hydrocarbon accumulation period was investigated using a suite of hydrocarbon generation and expulsion history,microfluorescence determination and temperature measurement *** to the homogenization temperature of the inclusions and the history of burial evolution,Yingcheng Formation has mainly two phases hydrocarbon *** first phase of oil and gas is charged before the reservoir is tightened,the oil and gas generated by Shahezi source rocks enter the sand body of Yingcheng Formation,influenced by the carrying capability of sand conducting layer,oil and gas is mainly conducted by the better properties and higher connectivity sand body and enriched in the east,which belongs to the type of densification after hydrocarbon *** second phase of oil and gas charge after densification,which belongs to the type of densification before the hydrocarbon accumulation.

关键词： Diagenetic evolution Fluid inclusion Porosity recovery Reservoir quality Hydrocarbon charging periods dongling area Oil-gas exploration engineering Songliao Basin Heilongjiang Province China

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中温温拌再生沥青性能研究

交通节能与环保 2024年第1期20卷 151-155页

作者：李彦青蔡莉莉吴春颖李健张东黄麒东南大学江苏南京210096 苏州市公路事业发展中心江苏苏州215000 南京宁通智能交通技术研究院有限公司江苏南京211135 苏交科集团股份有限公司新型道路材料国家工程研究中心江苏南京211112 南京工业大学江苏南京211816

本文对中温再生沥青制备工艺以及性能进行研究,通过试验研究了制备温度、剪切时间、中温再生剂掺量对中温再生沥青性能的影响。研究结果表明,(1)制备中温再生沥青的工艺条件为:70#基质沥青加热温度为120℃,中温再生剂加热温度为80℃,中... 详细信息

本文对中温再生沥青制备工艺以及性能进行研究,通过试验研究了制备温度、剪切时间、中温再生剂掺量对中温再生沥青性能的影响。研究结果表明,(1)制备中温再生沥青的工艺条件为:70#基质沥青加热温度为120℃,中温再生剂加热温度为80℃,中温再生剂在沥青中的剪切时间为90min;(2)中温再生剂提高了沥青的低温延展性,降低了沥青的黏度,提高了施工和易性;(3)老化沥青的针入度随着中温再生剂掺量的增加而增加,软化点随着中温再生剂掺量的增加而降低,对于70#基质沥青而言,中温再生剂的最佳掺量为沥青质量的4%。

关键词：中温温拌中温再生剂制备工艺沥青性能

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棉副产品全混合发酵饲料对育肥羔羊屠宰性能、肉品质及毛利润的影响

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饲料研究 2024年第5期47卷 1-6页

作者：邓沭洋杨成朱振宇俄广旭王明根王继姝卢冬郭雪峰塔里木大学动物科学与技术学院新疆阿拉尔843300 塔里木畜牧科技兵团重点实验室新疆阿拉尔843300

试验旨在探究饲喂不同比例棉副产品全混合发酵饲料对育肥羔羊屠宰性能、肉品质及毛利润的影响。试验选取36只健康、2~3月龄、体重(26.0±2.2) kg的卡拉库尔羊,随机分为3组,每组3个重复,每个重复4只羊。对照组饲喂100%的棉副产品全价饲料... 详细信息

试验旨在探究饲喂不同比例棉副产品全混合发酵饲料对育肥羔羊屠宰性能、肉品质及毛利润的影响。试验选取36只健康、2~3月龄、体重(26.0±2.2) kg的卡拉库尔羊,随机分为3组,每组3个重复,每个重复4只羊。对照组饲喂100%的棉副产品全价饲料,50%组饲喂50%棉副产品全混合发酵饲料+50%棉副产品全价饲料,80%组饲喂80%棉副产品全混合发酵饲料+20%棉副产品全价饲料。预试期15 d,正式试验期60 d。结果显示,与对照组相比,50%组和80%组羔羊的胴体重、净肉重、胴体净肉率、屠宰率显著升高(P0.05);50%组和80%组羔羊背最长肌的pH_(24 h)值、亮度值(L^(*))、红度值(a^(*))和肌内脂肪含量显著高于对照组(P<0.05),滴水损失、蒸煮损失和剪切力显著低于对照组(P<0.05);与对照组相比,50%组和80%组的毛利润分别提高1.81%和25.00%。研究表明,饲喂50%和80%棉副产品全混合发酵饲料能够提高育肥羔羊的屠宰性能,促进瘤胃、小肠和大肠的发育,改善肉品质,提高毛利润。

关键词：棉副产品全混合发酵饲料育肥羔羊屠宰性能肉品质毛利润

Dielectric Properties of Nanocrystalline TiO_(2) Prepared by the Stearic Acid Gel Method

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Chemical Research in Chinese Universities 2003年第3期19卷 347-349页

作者： dong Wei RUAN Sheng-ping ZHANG Xin-dong GUO Wen-bin LIU Cai-xia ZHANG Shuang jiA Cui-ping PAN jian-xuan CHEN Wei-you State Key Laboratory on Integrate Optoelectronics College of Electronic Sciences&Engineering Jilin UniversityChangchun 130023P.R.China

Nanocrystalline TiO 2 was prepared by means of a stearic acid gel method. The product was investigated by differential thermal analysis, thermogravimetric analysis, X-ray powder diffraction and transmission electronic microscopy(TEM). The results of the dielectric properties tested indicate that the dielectric constant of anatase-form nanocrystalline TiO 2 is much higher than that of the coarse crystal. The dielectric constant of the nanocrystalline material is not related with the amplitude of an external AC field in a certain range.

关键词： Nanocrystalline TiO_(2) Dielectric constant Dielectric loss