从《海峡西岸行》看主题性新闻的创新

主题性新闻报道是弘扬主旋律、实现正确舆论导向的重要途径。然而,当前我国此类报道普遍存在宣传味过重、缺乏吸引力等问题。系列直播报道《海峡西岸行》以其时效性强、生动活泼等特点从众多主题性新闻中脱颖而出,取得很好的收视效果。笔者从内容和形式两个角度,探讨其在主题性新闻创新上的成功之处

“月港、马尼拉与阿卡普尔科：全球化初期太平洋航路港市考古新进展”国际学术工作坊综述

16世纪晚期至19世纪初期,西班牙航海家建立并经营分别墨西哥的阿卡普尔科(Acapulco)与菲律宾马尼拉之间的跨北太平洋海路为主体的"马尼拉帆船(Manila galleons)航线",这一持续250多年的"新海上丝绸之路"是人类航海史上的创举,将东亚与美洲、欧洲紧密地联系起来,成为欧洲海洋势力东突西进、实现东西方早期贸易与全球化格局的重要一环。沉船遗存与港口史迹是"马尼拉帆船航路"是考古学调查、研究的两个主要对象,欧、美及东南亚的海洋考古学界已经积累了相当多的成果。2013年

Partitioning and transport of Polycyclic Aromatic Hydrocarbons in surface water from the downstream to Lingdingyang of Pearl River

为了研究河口水体中多环芳烃(PAHS)的相态分布、传输特征及其变化趋势,本文沿珠江下游至河口对表层水体PAHS进行采样分析。结果显示,16种优控PAHS的总浓度为(17.50~168.35)ng/l,平均83.40 ng/l,其中溶解相为(3.76~83.60)ng/l,颗粒相为(1.59~84.75)ng/l。PAHS浓度自下游至伶仃洋有波动降低的趋势,该趋势受陆源的持续输入、浮游植物的吸附吸收以及海水的稀释作用等因素的共同影响;PAHS组成及两相分配的变化主要受控于输入特征、悬浮颗粒物和黑碳吸附以及盐析效应等环境因子。荧蒽和芘的分配系数kP自珠江下游至伶仃洋的逐渐下降也说明了海水的稀释显著降低了悬浮颗粒物对PAHS的吸附。另外,特征化合物比值沿程的变化不仅指示了PAHS在广州段水体中较长的停留时间,也说明了虎门河口存在持续的PAHS输入。利用主因子分析和多元线性回归的方法,指示出煤和木材燃烧以及机动车排放是该区域表层水体PAHS污染的最主要来源,约贡献了80%的PAHS输入。In order to study the phase distribution,transport and variation of polycyclic aromatic hydrocarbons(PAHs),surface water samples were collected along the downstream to Lingdingyang of Pearl River.The total concentrations of 16 US EPA PAHs ranged from 17.50 ng /L to 168.35 ng /L with the average of 83.40 ng /L [dissolved phase:(3.76 ~ 83.60) ng /L,particle phase:(1.59 ~ 84.75) ng /L].The declining trend of PAHs concentrations was showed from the downstream to Lingdingyang under the influence of the terrestrial continuous inputs,phytoplankton adsorption and seawater dilution.Variations of PAHs composition and partitioning were controlled by input pathway,adsorption of suspended particulate matters(SPM) and black carbons and the salting out effect.The partition coefficients of Fluo and Py decreased gradually indicated that the water dilution affected the adsorption of SPM to PAHs.In addition,the trend of Fluo /(Py + Fluo) suggested the longer retention time of PAHs in downstream of Pearl River and the continuous inputs of PAHs in Humen estuary.The principal factor analysis indicated the coal and wood combustion and vehicle emissions were the major sources of PAHs in the surface water,which contributed almost 80%of PAHs input.国家自然科学基金项目(41276066

New method of variable excitation MFL testing under the condition of small magnetizing apparatus

为解决常规储罐和管道的漏磁检测(Mfl)方法中磁化器体积大、耗能多的缺点,提出了一种小型磁化器条件下的变励磁Mfl检测新方法。首先,分析了小磁化器条件下被测钢板磁化状态随外部励磁强度的变化特性,推导了偏置磁化条件下励磁通变化量与漏磁场变化率的关系模型;其次,根据所建立的关系模型,设计了一种新型变励磁Mfl检测探头,并给出变励磁Mfl法的系统实现方案;再次,结合实现方案,搭建了变励磁Mfl相应的实验平台;最后,在该平台上,开展了一系列的物理实验并对实验结果进行了深入讨论。实验结果表明,所提变励磁Mfl法无需对被测钢板进行局部饱和磁化,适合小型磁化器条件并具有较高的灵敏度。变励磁Mfl法为漏磁检测领域提供了一种新的检测思路。In the conventional method of magnetic flux leakage( MFL) testing,the magnetizer is in big volume and with more energy consumption.To solve the problem,a new method of variable excitation MFL testing under the condition of small magnetizer is proposed.First of all,the state of magnetized steel along with the change of the external excitation's intensity under the condition of small magnetizer is analyzed.Secondly,according to the established model,a new type of testing probe for the variable excitation of MFL is designed and a new implementation scheme is proposed.Furthermore,combining with the implementation scheme,an appropriate testing platform of the variable excitation MFL is set.Finally,a series of physical experiments on the platform are carried out and the results of the experiment were discussed.The experimental results show that the proposed method don't need to make local saturation magnetization of tested steel plate,which is suitable for the condition of small magnetizer with higher sensitivity.The new method provides a new testing idea for MFL testing field.国家自然科学基金(51177141); 中央高校基本科研业务项目(2010121041); 航空基金(2012ZD68003)资助项

New nondestructive test method with empirical research using local hysteretic loop characteristics

提出了一种利用局部磁滞回线特性的无损检测新方法。首先,研究了钢板内部缺陷对其动态磁导率分布的影响规律。其次,探讨了变励磁条件下局部磁滞回线的形成机理,并建立了动态磁导率与局部磁滞回线之间的关系模型。再次,根据所建立的关系模型,提出了一种利用局部磁滞回线特性实现对钢板缺陷进行无损检测的新方法,并给出检测系统的实现方案。最后,通过3d有限元法对实验模型进行仿真,并开展了一系列的物理实验进行了验证。结果表明,缺陷对钢板动态磁导率分布的影响显著,可利用局部磁滞回线特性来检测磁导率变化,从而达到检测内部缺陷,甚至背面缺陷的目的。所提新方法无需检测静态漏磁场磁感应强度,因此有效减小了磁化器体积。A new nondestructive test method based on local hysteretic loop characteristics is proposed in this paper.First of all,the influence law of the steel plate internal defects on the dynamic permeability distribution is studied,and the formation mechanism of the local hysteretic loop under the variable magnetic excitation condition is discussed.Secondly,the relation model between the dynamic permeability and local hysteretic loop is established.Furthermore,according to the proposed relation model,a new nondestructive test method of steel plate defects based on the local hysteretic loop characteristics is proposed,and the implementation scheme of the test system is given.Finally,the 3D finite element method was used to simulate the experiment model and a series of physical experiments were carried out to verify the proposed method.The results show that the steel plate defects have significant influence on the dynamic permeability distribution; the local hysteretic loop characteristics can be used to detect the permeability variation,and achieve the goal of detecting the internal defects of the steel plate,even the defects on the back of the steel plate.The proposed new method does not require to test the static leakage magnetic field,which reduces the volume of the magnetizing apparatus effectively.国家自然科学基金(51177141); 中央高校基本科研业务项目(2010121041); 航空基金(2012ZD68003)项目资

酪氨酸激酶抑制药GW2974诱导乳腺癌细胞BT474耐药的代谢机制研究

目的通过比较酪氨酸激酶抑制药GW2974给药后母本细胞株BT474与耐药株r BT474之间代谢相关因子mRNA表达的差异,探讨r BT474可能的耐药机制。方法收集对数生长期r BT474和BT474细胞,接种于96孔板,加入含有GW2974的培养基,分别于孵育0,12,24和48 h后,通过噻唑蓝法检测BT474与r BT474细胞的增殖情况。用逆转录实时定量-聚合酶链反应检测12种相关代谢因子葡萄糖转运体4(GLUT4)、2,6-二磷酸果糖激酶(PFK-2)、丙酮酸激酶2(PKM2)、乳酸脱氢酶(LDHA)、丙酮酸羧化酶(PC)、6-磷酸果糖激酶(G-6-PD)、脂肪酸合成酶(FASN)、脂酰肉碱转移酶1 (CPT1A)、葡萄糖调节蛋白75(GRP75)、电压依赖性阴离子通道蛋白1 (VDAC1)、葡萄糖调节蛋白78(GRP78)和钙网蛋白(CALR)的mRNA在BT474细胞和r BT474细胞中给药前后的表达水平。结果给予GW2974后,母本细胞BT474中糖脂代谢相关因子GLUT4、PFK-2、PKM2、LDHA、PC、G-6-PD、FASN和CPT1A的mRNA表达水平均明显下调,线粒体应激因子GRP75、VDAC1与内质网应激因子CALR表达水平均明显下调,内质网应激因子GRP78表达明显上调。而在耐药株r BT474中给药后这12种代谢相关因子的mRNA表达水平均明显上调。结论耐药株r BT474可能通过调控糖脂代谢以及细胞应激等过程使细胞耐受性增强。福建省自然科学基金面上项目(2012J01417

Preparation and Electrochemical Lithium Intercalation Performance of Segmented Carbon Nanofibers

以泡沫镍为催化剂 ,在 6 0 0和 70 0℃下 ,以CVD法热解乙炔气体制备大量的纳米碳纤维 .随着制备温度增加 ,纳米碳纤维直径变小 ,竹节状含量减少 ,d0 0 2 值减小 ,微晶片层平面Lc 和La 值增大 ,碳材料的可逆容量则下降 .分别用透射电镜、X射线衍射和拉曼光谱观察和测定了纳米碳纤维的形貌、微结构 ,发现在不同条件下生长的纳米碳纤维有不同的形貌和结构 .对纳米碳纤维的电化学嵌锂性能的研究表明 ,纳米碳纤维的结构对其电化学嵌锂容量和充放电循环寿命起重要影响 ,制备温度越低 ,纳米碳纤维的石墨化程度越差 ,可逆嵌锂容量相应要高一些Segmented carbon nanofibers were prepared by pyrolysis of acetylene on foam Ni at 600 and 700℃ in a fixed bed flowed-reactor. The morphology, microstructure and lithium insertion properties of these carbon nanofibers were investigated by TEM, XRD, Raman and electrochemical methods. Through TEM observations, it was found that this kind of carbon nanofibers was composed of lens-like segments with nearly equal separation stacking along the nanofiber axis. When the reaction temperature was 600℃, segmented carbon nanofibers were the major production. However, when the reaction temperature increased to 700 ℃, the content of segmented carbon filaments decreased and their diameter became smaller. The crystallite size d 002 and L c were determined by the 002 carbon Bragg peak of XRD patterns using the Bragg and Scherrer formulas. The intensity ratios of the 1350 cm -1 line and the 1580 cm -1 line (R=I D/I G) was used to evaluate the L a value, which was inversely proportional to the effective crystallite size in the direction of the graphite plane (L a). With the reaction temperature increased, the d 002 value decreased, L a and L c values increased, which indicated the degree of crystallinity increased. Segmented carbon nanofibers were used as positive electrodes of C/Li cells. The first charge capacities of C/Li cells were 480 and 300 mAh/g for samples produced at 600 and 700℃, respectively. The samples at 600℃ showed capacities higher than the theoretical value of graphite, which was attributed to accommodation of more lithium at the edge of graphene layers and on the surface of graphene layers according to the mechanisms of lithium insertion in carbons prepared by low-temperature pyrolysis of hydrocarbons. As confirmed by the XRD and Raman spectra, the samples at 700℃ had larger L a and L c, which led to the capacity decreasing.国家自然科学基金 (6 0 2 710 0 9);; 浙江省自然科学基金 (5 0 110 9,2 0 0 0 5 3)资助项

2018年安溪珠塔内窑调查报告

2018年5月至7月,厦门大学历史系考古专业、福建博物院文物考古研究所及安溪县博物馆等单位联合组成\"安溪古窑址调查队\",对安溪珠塔内窑进行了全面的调查,基本了解珠塔内窑古窑址分布与保存情况,采集了一批明末清初的青花瓷器、白瓷与窑具标本,并发现部分窑炉遗迹,为研究闽南地区青花瓷窑业发展提供了第一手资料

Preparation and electrochemical lithium intercalation performance of segmented carbon nanofibers

Segmented carbon nanofibers were prepared by pyrolysis of acetylene on foam Ni at 600 and 700degreesC in a fixed bed flowed-reactor. The morphology, microstructure and lithium insertion properties of these carbon nanofibers were investigated by TEM, XRD, Raman and electrochemical methods. Through TEM observations, it was found that this kind of carbon nanofibers was composed of lens-like segments with nearly equal separation stacking along the nanofiber axis. When the reaction temperature was 600degreesC, segmented carbon nanofibers were the major production. However, when the reaction temperature increased to 700degreesC, the content of segmented carbon filaments decreased and their diameter became smaller. The crystallite size d(002) and L-c were determined by the 002 carbon Bragg peak of XRD patterns using the Bragg and Scherrer formulas. The intensity ratios of the 1350 cm(-1) line and the 1580 cm(-1) line (R =I-D/I-G) was used to evaluate the L-a value, which was inversely proportional to the effective crystallite size in the direction of the graphite plane (L-a). With the reaction temperature increased, the d(002) value decreased, L-a and L-c values increased, which indicated the degree of crystallinity increased. Segmented carbon nanofibers were used as positive electrodes of C/Li cells. The first charge capacities of C/Li cells were 480 and 300 mAh/g for samples produced at 600 and 700degreesC, respectively. The samples at 600degreesC showed capacities higher than the theoretical value of graphite, which was attributed to accommodation of more. lithium at the edge of graphene layers and on the surface of graphene layers according to the mechanisms of lithium insertion in carbons prepared by low-temperature pyrolysis of hydrocarbons. As confirmed by the XRD and Raman spectra, the samples at 700degreesC had larger L-a and L-c, which led to the capacity decreasing