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基因治疗的现况和前景

遗传 , 1985,
Abstract: 早在人类开始种植谷物和驯养家畜起,就已经在自觉或不自觉地通过选择优良种子或种畜进行基因操作了。一百年以前英国博物学家高尔顿倡导的优生学则是一种将类似方法(控制生育)用于改善人类的理想。这种理想曾在本世纪的前四十年中风行一时,成为一种运动,引起了遗传学界的意见分歧。希特勒法西斯主义在三十年代的出现和以优生、种族卫生为“理
近50a来科尔沁地区沙漠化土地的动态监测结果与分析

中国沙漠 , 2003,
Abstract: 在明确了沙漠化土地的程度分级及其指标、监测方法的基础上,对科尔沁地区近50a来的沙漠化土地进行了遥感动态监测和分析。结果表明:科尔沁地区20世纪50年代未至70年代中期,是沙漠化土地扩展速度最快的一个时期,总面积增加了9084km2。从70年代中期到80年代后期,沙漠化土地继续呈快速增长之势,增加了9624km2;进入90年代,沙漠化过程呈现出逆转的趋势,沙漠化土地总面积由1987年的61008km2,减少到2000年的50142km2,减少了10866km2。就近50a来沙漠化土地变化的整体而言,经历了发展-再发展-逆转的过程。到2000年,科尔沁地区的沙漠化态势依然是严峻的。但从整个发展过程来看,沙漠化已呈现逆转的趋势。整个区域的生态环境在改善,环境容量在提高,继续发展下去,有望进入良性循环以保障生态环境与社会经济的可持续发展。
近50年来毛乌素沙地的沙漠化过程研究

中国沙漠 , 2001,
Abstract: 根据野外考察、应用遥感和地理信息系统技术对毛乌素沙地进行动态研究表明,50年代沙漠化土地面积约为12900km2,到了70年代中期达41110km2,80年代后期,减少为32590km2,至1993年又下降到了30650km2。50~70年代是沙漠化土地迅速发展的时期,而进入80年代以后,总体上是处于逆转过程中,已有近9460km2的沙漠化土地得到了治理,这主要得益于"三北"防护林工程的实施和当地政府与干部群众积极开展沙漠化防治的努力。也进一步证明了:沙漠化主要是人类造成的,也只有人类能够控制它。
我国内陆沙漠与海岸沙丘石英颗粒表面结构的对比研究

中国沙漠 , 1995,
Abstract: 本文通过扫描电镜分析,对我国内陆沙漠与海岸抄丘石英颗粒表面结构进行了对比研究。研究认为,无论是内陆沙漠砂或海岸沙丘砂,其石英颗粒都具有较好的磨圆度,表面有碟形坑、麻坑及SiO2沉淀物等代表风成环境的典型特征;此外,还叠加有代表原生沙物质来源于水下环境的V型撞击坑、撞击沟等痕迹。然而,受环境尤其是气候影响,其表面结构特征仍有差异,表现在内陆干旱区大陆性气候的沙漠砂的风成机械作用和化学沉淀作用,都要比沿海湿润季风性气候的海岸沙丘砂强烈;但海岸沙丘砂的化学溶蚀作用却比内陆沙漠砂要明显。同属海岸抄丘环境,其石英颗粒表面结构特征表现为北方温带海岸沙丘砂的机械作用痕迹强;而南方热带海岸沙丘砂的化学作用痕迹发育,但机械作用痕迹并非少见,仍然十分明显。
我校1993年招生计划创14年来最高记录

南京林业大学学报(自然科学版) , 1993, DOI: 10.3969/j.jssn.1000-2006.1993.02.015
Abstract: <正>经国家教委、林业部批准,我校1993年将在国内25个省、市、自治区招生,招生计划确定为950名。其中,国家任务613名,委托培养276名,自费生61名,计划总数比去年增长50%,比去年实际录取数增长32%,创14年来的最高记录。今年我校将继续深化招生改革,除了招收参加全国统考的考生外,继续试行单独录取,计划招收有实践经验的林区考生50人,定向生46人,中等林校保送生19人。招生的专业为:本科11个,即林学、森林保护、园林、森林采运工程、林业机械、木材加工、林产化工、家具设计与
网格技术及其应用分析

武汉理工大学学报 , 2008,
Abstract: ?构筑网格是为了提高计算机资源的共享能力,它以分布共享性、自相似性及整体性、动态多样性以及自治虚拟性等为特点。从介绍网格的核心概念入手,并深入分析了网格技术的关键要素及核心问题,在此基础上讨论网格的体系结构和开发平台。通过实例展示了网格技术目前的广泛应用,对其应用优势加以分析。
乡村医院医疗废物焚烧填埋现况分析
Incineration and landfill of medical waste in rural hospital

??
- , 2016,
Abstract: 摘要:目的 对乡村医院医疗废物的焚烧、填埋方式现况进行调查,了解其对周边环境的影响。方法 采用调查员现场问卷调查的方法,当场填写调查表,并确认调查内容。结果 共发出问卷400份,回收400份,筛选有效卷310份,结果显示,医疗废物焚烧的占48.7%,填埋的占47.7%,送管理站的占3.6%。焚烧情况,乡镇卫生院比村卫生室和诊所的方式要好(P<0.001),填埋方式没有区别(P>0.05);村卫生室和诊所处理方式没有区别(P>0.05);周边89.1%的村民认为医疗垃圾的焚烧和填埋污染环境。结论 乡村医院医疗废物处理方式以焚烧、填埋为主,而且方法原始、简单,对周边环境污染较大,亟待解决。
强流脉冲离子束辐照铜靶热效应数值研究
Research on Thermo Effects of Cu Modified by Intense Pulsed Ion Beam
 [PDF]


Modern Physics (MP) , 2013, DOI: 10.12677/MP.2013.31003
Abstract: 为了研究强脉冲离子束辐照改性铜靶的行为,建立了基于靶室中法拉第杯检测的离子束流密度和离子加速电压时空分布模型;采用蒙特卡罗方法计算了束流在铜靶中的能量沉积,并将这随时间变化的非线性沉积能量作为热传导方程的热源项,计算得到了脉冲期间靶材内部温度场的演化规律。一次脉冲后与液化烧蚀相比,靶材表面较小区域的物质气化烧蚀掉,辐照中心处熔化的厚度最大;气、液化烧蚀厚度随偏离中心位置而减小。当束流密度为300 A/cm2时,中心区域气化烧蚀和液化烧蚀的厚度分别达到0.2微米和1.3微米;脉冲期间热量延纵深方向的传播距离小于2微米。
A modification method for Copper target by intense pulsed ion beam (IPIB) irradiation has been reported. Based on the temporal and spatial distribution models of the ion beam density detected by Faraday cup in the chamber and the ions accelerating voltage, the energy deposition of the beam ions in Cu is calculated by Monte Carlo method. Taking this time-dependent nonlinear deposited energy as the source term of two-dimensional thermal conduction equa- tion, the temporal and spatial ablation process of metal Cu during a pulse time was obtained. Only a little area of mate- rial is ablated off due to the vaporization compared with the melting ablation area on the surface after a shot. The most deep melting depth is in the irradiation centre. The melting and vaporizing thicknesses decrease with the increasing dis- tance from the irradiation centre. The top-layer Copper material in thickness of about 0.2 μm is ablated by vaporization and the layer in thickness of 1.3 μm is melted after one shot under the ion beam density of 300 A/cm2. The thermal transportation along the longitudinal direction in the specimens is less than 2.0 μm during a pulse.
关于高中生学习幸福感的调查
Study on High School Students’ Learning Well-Being
 [PDF]

珍珠
Advances in Psychology (AP) , 2014, DOI: 10.12677/AP.2014.43066
Abstract:

以广东省734名高中毕业生为调查对象,进行学习幸福感问卷调查研究,结果显示:1) 高中学习幸福感、学习满意度水平中等偏上,情绪正向、偏向积极;2) 学习幸福感、学习满意度和学习情绪体验两两呈显著正相关;3) 36%的高中生认为,增强学习意志力是提升他们自身学习幸福感的重要途径。
The study investigated the level of high school students’ learning well-being and the way to improve learning well-being with 734 high school graduates in Guangdong Province. Our results showed that: 1) learning well-being and learning satisfaction of high school students are above the average level, and their learning emotional experience is positive; 2) there are positive pairwise correlations among learning well-being, learning satisfaction and learning emotional experience; 3) 36% of high school students agree that enhancing learning willpower is an important and effective way to improve learning well-being.

颍河上游褚河段古洪水事件及其沉积响应
Ancient Flood Events in Upstream Reaches of the Ying River and the Depositional Response
 [PDF]


Open Journal of Soil and Water Conservation (OJSWC) , 2015, DOI: 10.12677/OJSWC.2015.31001
Abstract:
通过对颍河上游禇河镇段一处典型的古洪水滞流沉积层剖面(SWD)的粒度、磁化率等指标进行综合研究,并结合野外特征描述,分析了该剖面理化特征,探讨了该地区发生洪水的次数。研究结果表明:1) 在YH-CH剖面粒度组成中以粉砂为优势粒径,含量介于47%~85%之间,平均含量为64.3%;粘粒含量较少,含量波动于3.2%~9.5%之间,平均为5.3%;砂级颗粒平均含量为17%;在累计频率曲线图上,B、C、D、E等层位偏左,SWD1和SWD2偏右;SWD1和SWD2分选较好且沉积颗粒较粗。2) 该剖面低频磁化率(X-lf)和高频磁化率(X-hf)具有相似的变化趋势,都呈现出B、C、D、E磁化率值相对较高,而SWD1与SWD2磁化率值相对较低,说明了SWD1和SWD2为典型的古洪水滞流沉积物。综合研究表明,YH-CH剖面记录两期古洪水事件,对应的剖面深度分别为60~80 cm、180~200 cm,其中第一期洪水较第二期洪水能量较高,携带的沉积物颗粒较粗。同时这些特征也为颍河上游的古洪水事件的识别标志提供参考。
Based on the test of grain size and magnetic ability from typical flood slack water deposits (SWD) in the Chuhe site, in upstream reaches of the Ying River, coupled with filed description, we analyze its physicochemistry features and discuss the sedimentary characteristics when floods happen. The results show that: 1) in the grain size of YH-CH profile, silt that varies from 47% - 85% is the main constituent, and the average level is 64.3%; clay content is less, between 3.2% and 9.5%, and its average level is 5.3%. Average sand-size particles’ content is 17%; on the cumulative frequency cure, B, C, D, and E incline to the left, and however, SWD1 and SWD2 incline to the right. It is obvious that SWD1 and SWD2 are special ancient flood slack water sediments; 2) the section of low-frequency magnetic susceptibility (X-lf) is in line with high-frequency magnetic susceptibility (X-hf) broadly in a changing trend; the magnetic susceptibility value of B, C, D, and E is relatively high, and the magnetic susceptibility value of SWD1 and SWD2 is relatively low. According to the experimental analysis, we conclude that the profile recorded two kinds of flood. And the depth of the corresponding profiles respectively is from 60 to 80 cm and 180 to 200 cm; the energy of the first ancient flood that carried a lot of coarse matters is higher than that of the second ancient flood. In addition, the study of sedimentary characteristics provides the reference for the identification of ancient floods in upstream reaches of the Ying River.
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