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1.
成人英语学习动机行为调查与教学对策研究   总被引:3,自引:0,他引:3  
动机是激励人们行动的心理动因.英语学习动机是推动英语学习的内部动因,成人英语学习动机是复杂的.了解他们的英语学习动机特点有利于教师改进教学手段和策略,激发与培养其学习的主动性和积极性,发挥其学习潜能,从而提高英语学习的效果.运用定量研究的方法,在年轻干部学员中进行学习动机调查,分析了其学习动机的特点,并提出成人英语教学的对策.  相似文献   

2.
鄂尔多斯盆地致密油气资源丰富,其中陇东地区长6储层的发育受多物源体系的控制,成为当前研究热点,但目前对不同物源控制的砂体微观结构特征差异等缺乏深入了解,制约了该地长6储层的勘探与评价。通过铸体薄片鉴定、镜下观察、X衍射及恒速压汞分析等实验手段,开展了不同物源体系控制下的储层微观结构特征研究,对比分析了沉积微相对储层发育的影响,建立了对应的孔隙演化模型,并探讨了主要成岩作用对储层致密化的控制。结果表明:(1)喉道是控制储层渗透率的主要因素,北东部物源沉积区较西部物源沉积区的喉道发育状况更好,渗透率更高;(2)随着渗透率升高,受北东部物源控制的南梁地区半径大于0.50μm的较大喉道对渗透率的贡献明显增加;(3)沉积微相是控制不同物源体系砂体物性的重要因素,受北东部物源控制的南梁地区的砂质碎屑流和浊流砂体物性均好于受西部物源控制的樊家川地区;压实作用是造成储层致密化的主要原因,受不同物源体系储层伊利石和绿泥石含量差异的影响,北东部物源沉积区压实减孔量(19.29%)小于西部物源沉积区(22.32%)。该研究成果对不同物源体系致密油的后期评价具有指导意义。  相似文献   

3.
断裂在贝尔凹陷油运聚成藏中作用   总被引:3,自引:3,他引:0  
为研究断裂在贝尔凹陷油运聚成藏中的作用,通过油藏解剖分析油藏与断裂之间空间匹配关系.结果表明:贝尔凹陷油藏从基岩至大磨拐河组皆有分布,主要为断层油藏和受断层控制的基岩潜山油藏,平面上主要分布在与断裂活动有关的凹间隆、洼中隆、斜坡断阶带上.贝尔凹陷主要发育早期伸展、中期走滑和晚期反转(或长期发育)3种类型断裂,断裂对贝尔凹陷油运聚成藏主要起3方面控制作用:(1)长期发育断裂为南一段源岩生成油向大磨拐河组运移提供输导通道,早期伸展断裂错断使源储侧接,南一段源岩生成的油向基岩、铜钵庙组和南屯组储层侧向运移;(2)早期伸展断裂为基岩、铜钵庙组和南屯组油聚集提供遮挡条件;(3)断裂活动为不同层位油聚集提供构造背景.在贝尔凹陷断裂控藏有早期伸展断裂遮挡油聚集成藏和长期发育断裂输导油聚集成藏2种模式.  相似文献   

4.
利用RACE(Rapid-amplification of cDNA ends)克隆技术从泰国斗鱼(Betta splendens)精巢中克隆抗缪勒氏管激素(Anti-Müllerian hormone,AMH)基因的c DNA序列,分析该基因序列与其他物种的差异,并用RT-PCR半定量方法分析其组织表达的性别差异。结果表明:泰国斗鱼AMH基因的cDNA序列全长为1 804 bp,其中开放读码框为1 596 bp,编码532个氨基酸残基,与其他物种的氨基酸序列差异较大,同源性最高仅55%;AMH前体蛋白的系统进化树显示,泰国斗鱼与尖吻鲈(Lates calcarifer)亲缘关系最近;AMH基因的组织表达有明显的组织特异性及性别差异,在性腺中表达量最高,雄性个体脑、脾和肌肉次之,垂体、肝、肾、心和肠中未检测到AMH表达,雌性个体脾、心脏和肌肉次之,脑、垂、肝和肾中未检测AMH表达。  相似文献   

5.
以霸县凹陷东三段古物源体系为例,对其进行了不同角度与不同层次的精细研究,进而探讨了霸县凹陷断-坳转换期的物源体系特征及其控制因素。结果表明,霸县凹陷断-坳转换期物源特征主要受古构造与古气候的控制,表现为:一方面,受继承性裂陷末期断陷样式的影响,凹陷快速地构造沉降,使得隆凹格局明显,易于形成近源堆积;另一方面,受古气候频繁变化的影响,气候干燥时,整体处于暴露环境,加速了剥蚀速度,气候潮湿时,沉积范围扩大,加速了凹陷填平补齐,准平原化。在古构造和古气候双重因素控制下,形成了霸县凹陷断-坳转换期独特的物源特征,表现为以凹陷边缘凸起为主的近物源慢速堆积特征。综合多种物源分析方法,得出研究区物源来自东部的大城凸起和西部的牛驼镇凸起,具体包括东部的长丰镇物源;史各庄物源和苏桥物源;西部的膮州物源和岔河集物源;南部的饶阳物源和北部的南孟物源。在物源体系、构造组合特征及气候的控制下,东三段主要发育扇三角洲和浅水三角洲沉积体系。   相似文献   

6.
【目的】探究海洋土霉菌代谢产物epi-aszonalenin A(EAA)对氧化型低密度脂蛋白(ox-LDL)诱导HUVEC人脐静脉内皮细胞的动脉粥样硬化斑块内血管新生的作用。【方法】用CCK法检测细胞活力,DCFH-DA法测定活性氧(ROS)的含量,划痕实验检测细胞迁移能力,血管生成实验检测细胞成管能力,酶联免疫吸附法ELISA试剂盒检测LOX-1和VEGF蛋白表达情况,蛋白免疫印迹法检测MAPK通路、细胞间黏附分子-1(ICAM-1)、血管细胞黏附分子-1(VCAM-1)的蛋白的表达情况,分子对接模拟EAA与LOX-1蛋白的相互作用。【结果】CCK法证明EAA对HUVEC细胞无明显毒性作用(P>0.05);与空白组相比,EAA对HUVEC细胞的迁移和血管生成起到显著抑制作用(P<0.001);与对照组相比,随着实验组EAA浓度增加,细胞内ROS含量显著减少(P<0.001),LOX-1、VEGF、MAPK通路蛋白p38、JNK、ERK的磷酸化和ICAM-1、VCAM-1的表达也显著降低(P<0.001);此外EAA能与LOX-1形成稳定的相互作用。【结论】EAA能清除ROS,抑制HUVEC细胞炎性因子的表达和血管生成。  相似文献   

7.
为研究南堡凹陷天然气成藏分布规律,在天然气藏类型及分布特征研究的基础上,分析天然气分布与成藏条件之间空间匹配关系,研究南堡凹陷天然气成藏模式及其主控因素.结果表明:南堡凹陷天然气存在4种成藏模式:源内断裂输导中—浅层断层圈闭天然气成藏模式,天然气聚集层位受输导断裂与馆陶组三段火山岩盖层配置和储层发育共同控制;源内断裂输导中—深层断层圈闭天然气成藏模式,天然气聚集层位受输导断裂与东营组二段泥岩盖层配置控制;源内断裂输导深—浅层断层圈闭天然气成藏模式,天然气聚集层位受储层发育和源岩供给程度共同控制;源外边部断裂输导深层断层圈闭天然气成藏模式,天然气聚集层位受储层发育和源岩供给程度共同控制.该结论对指导南堡凹陷天然气勘探具有指导意义.  相似文献   

8.
为明确四川盆地须家河组致密砂岩物源特征及控储作用,运用储层岩石学测试和镜下分析,研究了物源与储层发育的关系及分布,探讨了物源体系的控制因素。研究结果表明,四川盆地须家河组储层具有成分成熟度较低、物性差异性强、以中-细粒为主、主要为溶蚀孔隙和成岩效应存在两面性5个基本特征;物源控制了储层岩石类型的发育范围,平面展布存在差异性,其可溶矿物组分及含量亦有所不同,导致各地区孔隙发育及规模有所不同;西部龙门山和东北部大巴山是须家河组的主要供源区,前者表现为碳酸盐岩岩屑含量相对较高,后者表现为火山岩岩屑含量相对较高。不同时期造山活动强度的阶段性变化使得物源供应强度及类型也随之变化,储层岩石组分差异分化,进而控制储层垂向非均质性。研究成果可以为该区下一步的油气精细勘探提供借鉴。   相似文献   

9.
Melut盆地为非洲内陆一个重要含油气盆地,其北部具有下白垩统生油、古近系聚集成藏的远源成藏特征,明确盆地远源油藏形成条件与控制因素是提高远源油藏勘探成功率、寻找新的勘探领域的关键。基于区域石油地质条件与油藏解剖,开展了Melut盆地北部远源油藏形成条件、类型及特征研究,在此基础上提出了源内Yabus组远源断层-岩性复合油藏及源外Yabus组远源断块油藏两大潜力勘探领域。研究表明:Melut盆地北部古近系Yabus组发育源内和源外2种类型的远源油藏,二者具有不同的油气充注方式与成藏模式。源内Yabus组远源油藏的形成取决于3个地质条件的耦合,即"两强一弱"的3期裂陷作用为古近纪Yabus组-Adar组远源储盖组合的形成创造了条件;富油凹陷的发育为Yabus组远源油藏的形成提供了必要的油源基础;多期裂陷作用为Yabus组远源圈闭的油气充注提供了垂向通道条件。源内远源油藏主要通过油源断裂的垂向充注成藏,油源断裂是其成藏的主要控制因素,油源断裂的识别及控圈断层的侧向封堵性评价是源内远源断块圈闭评价的重点。源外远源油藏主要通过富油凹陷的侧向运移充注成藏,由富砂地层与断块、古隆起形成的输导脊控制源外远源圈闭的成藏,输导脊的识别与圈闭充注油气程度研究是源外远源圈闭评价的重点。研究成果指导了Melut盆地远源油藏的勘探部署与深化勘探,对其他含油气盆地成熟探区远源油藏的勘探具有指导和借鉴意义。   相似文献   

10.
以鱼粉、酪蛋白和明胶为蛋白源,分别以20%添加水平的葡萄糖、糊精、蔗糖、玉米淀粉、小麦淀粉和马铃薯淀粉为糖源,配制成6种不同糖源的等氮等能饲料,研究不同糖源对方斑东风螺幼螺生长性能、饲料利用、消化酶活性、糖原含量、蛋白质含量及肉壳比的影响。结果表明:方斑东风螺幼螺的增重率、特定生长率、饲料系数、蛋白质效率,消化酶活性、糖原含量、蛋白质含量及肉壳比均受到糖源种类的显著影响(P<0.05)。增重率、特定生长率从高至低依次为小麦淀粉组、玉米淀粉组、马铃薯淀粉组、糊精组、葡萄糖组、蔗糖组;饲料系数及蛋白质效率均以小麦淀粉组表现最好,与马铃薯淀粉组和玉米淀粉组无显著性差异,显著优于糊精组、葡萄糖组及蔗糖组。消化酶活性的分析结果表明,淀粉酶活性最高的是蔗糖组和小麦淀粉组,糊精组次之,葡萄糖组和马铃薯淀粉组的淀粉酶活性最低;各处理组脂肪酶活性存在显著差异,从高至低分依次为马铃薯淀粉组>小麦淀粉组>糊精组>玉米淀粉组>蔗糖组、葡萄糖组;蛋白酶活性以小麦淀粉组最高,其次为蔗糖组,其他糖源组并无显著差异;而内脏团糖原和肌糖原含量,除了葡萄糖组外,其他各组差异不显著(P>0.05);蛋白质含量以葡萄糖组最高,小麦淀粉组最低,而肉壳比则刚好相反,以小麦淀粉组和玉米淀粉组最高,葡萄糖组最低。以生长、饲料利用率和消化酶活性为评价指标,方斑东风螺饲料中采用小麦淀粉作为糖源效果最优。  相似文献   

11.
采用Wright’s-Geimsa混合染料对三疣梭子蟹、锈斑蟳和锯缘青蟹的血淋巴细胞进行染色,光镜下对这三种海水蟹的血淋巴细胞进行了观察和比较。根据血淋巴细胞的核质比、细胞整体着色特点、细胞质中颗粒的存在与否、颗粒的数量和分布等,三种海水蟹的血淋巴细胞均可分为颗粒细胞、半颗粒细胞和透明细胞三种主要类型,三种蟹的同类血淋巴细胞在染色形态上稍有差别。三种蟹的颗粒细胞大小差异较大,而半颗粒细胞和透明细胞大小相近。三种蟹的血淋巴细胞均以半颗粒细胞为主,透明细胞在血淋巴细胞中所占比例最小。三种蟹的血淋巴细胞密度均存在明显的雌雄差异,锈斑蟳和锯缘青蟹血淋巴细胞分类计数也存在明显的雌雄差异。  相似文献   

12.
日本Ms9.0地震前的连续重力观测异常   总被引:1,自引:1,他引:0  
日本Ms9.0地震后,检测了17台(套)gPhone重力仪和成都GS15连续重力观测仪震前3天的观测数据.发现:乌什、郑州台的gPhone重力仪和成都台的GS15重力仪分钟采样在震前3天出现了不明原因的高频异常现象.初步分析表明,成都、乌什在3月9日的日本Ms7.3地震前的16小时产生了纺锤状的隆起现象;郑州台在日本M...  相似文献   

13.
Place attachment is an important motivation for people to spend more time outdoors and to protect landscapes. This study explores visitors’ intention to conserve natural landscapes based on the relationship with their place attachment to National Park landscape. Structural equation modelling (SEM) was used to determine the relationship between landscape conservation and place attachment. A survey with a structured questionnaire was administered to visitors to the seven designated hiking courses of Harz National Park in Germany. The path coefficient of 0.77 revealed that place dependence positively and significantly affected place attachment, whereas place identity did not. Place attachment had a significant effect on both affective appraisals and visiting satisfaction. Higher place attachment led to higher emotional reaction to landscapes on site and higher satisfaction of visiting the park. Among the variables, visiting satisfaction, but not affective appraisals, played a statistically significant mediating role between place attachment and conservation intention. With a path coefficient of 0.86, conservation intention was highly affected by visiting satisfaction. These results suggest that the managers of National Parks should focus on increasing visiting satisfaction based on how visitors are emotionally bonded with their visiting places, in order to enhance the intentions to conserve the landscape of the visitors to National Parks.  相似文献   

14.
审美意象是作家精神的符号和标志。屈原与柳宗元"骚怨"意象的主要差异,一是意象选择从神奇瑰丽转向世俗怪异,二是意象表达由连类比兴变为整体象征和寓言,三是意象关系由主客融合转向部分反常乖离。造成这种差异的客体原因主要是时代、环境和风俗的变化以及历史审美风尚的变迁;而主体原因则主要是屈、柳神秘思维与理性思维的不同建构。透过两者的差异及其成因,可以更好地把握屈、柳"骚怨"精神的个性特点。  相似文献   

15.
This paper examined visitors to Bukhansan National Park in Korea based on first-time and repeat visitation. Bukhansan National Park is Korea’s most heavily visited national park with annual visitation of six million visitors in 2015. Data used in this article were collected on-site in the park in 2007 and 2013 by the Korea National Park Service (KNPS). The study variables included socio-demographics, travel behavior, motivation, and satisfaction with park attributes, services and facilities. Data were analyzed by each study year for first-time and repeat visitors. Results showed significant differences for both first-time and repeat visitors on several socio-demographic, travel behavior, and motivation variables within each study year. For satisfaction with park attributes, facilities and services, first-time visitors were significantly different from repeat visitors on seven variables for both years. Implications are given regarding programs and services to improve visitor satisfaction and sustain the natural, cultural and historical resources at Bukhansan National Park and other national parks in Korea. Future research suggestions are provided to learn more about visitor characteristics, standards of quality and preferences in the national parks.  相似文献   

16.
In this study, Bayesian probability method and machine learning model are used to study the real occurrence probability of earthquake-induced landslide risk in Taiwan region. The analyses were based on the 1999 Taiwan Chi-Chi Earthquake, the largest earthquake in the history in this Region in a hundred years, thus can provide better control on the prediction accuracy of the model. This seismic event has detailed and complete seismic landslide inventories identified by polygons, including 9272 seismic landslide records. Taking into account the real earthquake landslide occurrence area, the difference in landslide area and the non-sliding/sliding sample ratios and other factors, a total of 13,656,000 model training samples were selected. We also considered other seismic landslide influencing factors, including elevation, slope, aspect, topographic wetness index, lithology, distance to fault, peak ground acceleration and rainfall. Bayesian probability method and machine learning model were combined to establish the multi-factor influence of earthquake landslide occurrence model. The model is then applied to the whole Taiwan region using different ground motion peak accelerations(from 0.1 g to 1.0 g with 0.1 g intervals) as a triggering factor to complete the real probability of earthquake landslide map in Taiwan under different peak ground accelerations, and the functional relationship between different Peak Ground Acceleration and their predicted area is obtained.  相似文献   

17.
This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions,and between medicinal plants and all vascular plants.We used the published sources for elevation records of 2,331 medicinal plant species to interpolate presence between minimum and maximum elevations and estimated medicinal plant richness for each 100-m elevational band. Monte Carlo simulations were used to test whether differences in elevational distribution between different groups of medicinal plants were significant. Total number of medicinal plants as well as different groups showed unimodal relationship with elevation. The elevational distributions of medicinal plants significantly differ between regions and between medicinal plant groups.When comparing the richness of all medicinal plants to all vascular plants,Monte Carlo simulations indicated that the numbers of medicinal plants are higher than expected at low elevations.The highest richness of medicinal plants at low elevation could be possibly due to favorable environmental factors such as high temperature, rainfall,sunlight or due to higher density of human population and thus higher pressure on use of any plants in lower elevations.  相似文献   

18.
交配前雄性大鼠分别按每 kg 体质量1.25、2.50、5.00 g 的剂量灌服半叶马尾藻多糖,连续灌胃60 d,雌性大鼠分别以相同剂量连续灌胃14 d,以雄雌1∶1的比例合笼5 d,每天做阴道分泌物涂片检查,见精子者记为妊娠第1天,交配后雄鼠处死,测定血清睾酮(T)水平,取雄鼠附睾进行精子成活率、精子计数和精子畸形率测定,计算睾丸、附睾脏器比,并进行病理组织学检查;雌鼠继续灌胃至妊娠7 d,于妊娠14 d 处死,计算受孕率、着床数、黄体数、死胎、活胎和吸收胎,测定血清促卵泡生成素(FSH)、黄体生成素(LH)和雌二醇(E2)水平,计算脏器比并进行病理组织学检查.结果显示,给药组大鼠的精子成活率、精子计数、精子畸形率、受孕率、着床数、黄体数、死胎、活胎、吸收胎、睾丸、附睾和卵巢脏器比以及血清 T、FSH、LH 和 E2水平与对照组相比差异无统计学意义(P >0.05),生殖器官病理组织学检查未见明显异常.在本实验条件下,半叶马尾藻多糖对大鼠无明显生殖毒性  相似文献   

19.
The spatial and seasonal pattern of macrozoobenthic structure and its relationship with environmental factors were studied from July 2006 to April 2008 in Mingzhu Lake, Chongming Island, Shanghai at the Changjiang River mouth. The congruences in water quality bioassessment based on diversity and biotic indices and using different taxonomic categories were also explored to find the best assessment method of water quality for the lake. All major structural characteristics of macrozoobenthic community, including species composition, abundance, biomass and four biomass-based diversity indices (Shannon’s diversity, Simpson’s diversity, Pielou’s evenness and Simpson’s evenness index) fluctuated significantly in season but in space. The above four abundance-based diversity indices plus abundance-based Margalef’s richness index did not display significant spatial variations; and significant seasonal differences were found in three indices only. Water temperature was the key environmental factor responsible for macrozoobenthic spatio-temporal distribution patterns. Water quality assessed by Shannon’s index (H a′) and biological pollution index (BPI) rather than the other four biotic indices were consistent with those by trophic state index (TSI). Results from chironomids and oligochaetes did not always agree to those from the whole community when H a′ or Hilsenhoff biotic index was applied to bioassessment. Therefore, combining multiple indices and avoiding a single taxonomic category to assess water quality are strongly recommended and in Mingzhu Lake using a mixture of H a′ and BPI will ensure the most effective investigation of water quality. Our results also show that the main structural characteristics of macrozoobenthic communities in the small lake may display consistent spatial patterns.  相似文献   

20.
二穗短柄草是一种理想的研究温带禾谷类植物和牧草的模式植物。对源于以色列4个不同地区(群体)90个生态型二穗短柄草的物候期和农艺性状差异及其相关性进行了研究。结果表明,在贵州自然气候条件下,以色列二穗短柄草生态型间和群体间在生长期、各农艺性状表现均有所不同,方差分析呈极显著差异(P<0.0001);各群体生长期平均值的顺序为:Tibigha相似文献   

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