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Search Results: 1 - 10 of 42235 matches for " 武银婷 "
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基于Ganley理论含有衰减特性零偏VSP正演研究及修正
,朱光明,刘伊克,常旭
地球物理学报 , 2011, DOI: 10.3969/j.issn.0001-5733.2011.09.020
Abstract: 含有衰减的VSP资料能够提供丰富的地下岩层和岩性信息,本文根据Ganley理论对其进行了正演计算.引入品质因子Q值,考虑界面发生反射和透射,对震源位于地表及地下某一深度进行讨论,分别计算水平层状介质中的下行波和上行波.与不含有衰减特性的正演记录及其时频分析对比可以看出,高频成分的吸收、主频的降低、较多的能量衰减揭示了地层的非弹性性质.另外,当震源位于第一层介质以下时,按照Ganley理论公式计算得到的震源上方地层的下行波同相轴比直达波先出现,产生向上时移的现象,这表明了其波场运算存在提前到达的误差.为此,对震源上方传输系数矩阵进行修正,下行波在直达波到达后,才从分界面的位置开始出现,符合传播规律,正演结果显示了修正的合理性.
不同抗性烤烟根系分泌单糖特征及其对黑胫病菌的化感效应
桑正林,杨顺强,,,,赵启君
- , 2018,
Abstract: 为探讨烤烟根系分泌单糖的品种差异及与黑胫病的相关性,该研究以‘NC102’、‘K326’、‘云87’和‘红花大金元’4个烤烟品种为试验材料,测定了各烤烟品种根系、根际土中的单糖及对黑胫病的化感作用。结果表明:(1)在各烤烟品种的根系和根际土中均检出了木糖、阿拉伯糖、葡萄糖和半乳糖,检出的糖组分中以葡萄糖含量最高。(2)在烤烟团棵期时,根际土中的葡萄糖含量在高抗品种‘NC102’和中抗品种‘K326’中分别为2.255和4.744 μg·g-1,中感品种‘云87’和高感品种‘红花大金元’分别为7.100和11.068 μg·g-1;各烤烟品种团棵期时根际土中的单糖总量表现为:‘NC102’(5.346 μg·g-1)<‘K326’(7.844 μg·g-1)<‘云87’(10.551 μg·g-1)<‘红花大金元’(15.579 μg·g-1)。(3)根际土中葡萄糖含量、单糖总量均表现为感病品种高、抗病品种少的趋势;感病品种根际土中单糖总量在团棵期时高,而在其他时期时较低。(4)各单糖和混合糖溶液对黑胫病菌的生长均表现为促进作用,单一糖在2.000 mg·mL-1处理下促进作用最强,混合糖在4.000 mg·mL-1处理下促进作用最强。研究发现,烤烟感病品种在生长发育前期通过根系分泌较多的单糖到根际土中,为土壤中黑胫病菌的生长发育提供了物质和能源,促进了烟草黑胫病菌的生长,导致烟草黑胫病的发生。
河南地区7岁以下儿童生长发育与贫血状况调查
A survey on status of growth and development and prevalence of anemia of children under 7 years old in Henan Province

袁恩,张玉??,贾莉,,吕忠兴
- , 2016,
Abstract: 目的:了解河南地区7岁以下儿童生长发育和贫血状况,为制定相关政策提供依据。方法:采用分层整群随机抽样法抽取河南省3个城市、2个县和1个县级市的7岁以下儿童2 165人,采用Z评分法评价儿童的生长发育状况,并调查贫血患病率,比较不同年龄、性别和地区儿童之间的差异。结果:河南地区7岁以下儿童低体重率、生长迟缓率、消瘦率、超重率和肥胖率分别为0.60%、1.34%、0.88%、8.68%和2.82%,头围偏小率和偏大率为2.10%和1.47%,贫血患病率为3.60%。不同年龄组儿童之间生长迟缓率(P=0.005)、超重率(P<0.001)和肥胖率(P<0.001)比较,差异有统计学意义。男童超重率(P=0.010)和肥胖率(P=0.028)高于女童,而女童低体重率(P=0.038)和头围偏小率(P=0.043)高于男童。乡镇儿童消瘦率高于城区(P=0.045)。不同年龄组儿童贫血患病率比较,差异有统计学意义(P<0.001),2岁以下儿童的贫血患病率最高。结论:河南地区7岁以下儿童生长发育优于WHO标准,但5~7岁儿童超重和肥胖趋势明显,2岁以下儿童贫血率高的问题不容忽视。
Aim: To investigate the status of growth and development and the prevalence of anemia among children under 7 years old in Henan Province, so as to provide references for making relevant policies.Methods: Stratified random sampling method was used to recruit 2 165 children under 7 years old from three urban districts, one county??level city and two counties in Henan Province. Z scores were used to assess the status of growth and development of the children, and the prevalence of anemia was also investigated. Comparisons of the differences were based on age, gender and areas. Results: Among children under 7 years old in Henan Province, the prevalence of underweight, stunting, wasting, overweight and obesity was 0.60%, 1.34%, 0.88%, 8.68% and 2.82%, respectively. The prevalence of small head circumference and large head circumference was 2.10% and 1.47%, and the prevalence of anemia was 3.60%. There were significant differences in stunting(P=0.005), overweight(P<0.001) and obesity(P<0.001) among different age groups. The prevalence of overweight(P=0.010) and obesity(P=0.028) of boys were higher than the girls, while the prevalence of underweight(P=0.038) and small head circumference(P=0.043) of girls were higher than the boys, furthermore the prevalence of wasting in rural areas was higher than the urban areas(P=0.045). There was significant difference in prevalence of anemia among different age groups(P<0.001), and the prevalence of anemia in children under 2 years old were the highest.Conclusion: The growth and development of children under 7 years old in Henan Province are better than WHO standards, but the trends of overweight and obesity between 5 to 7 years old children are obvious, and more attention should be paid to the high prevalence of anemia in children under 2 years old
改进的1范数匹配滤波法及在南海深水盆地的应用
,刘伊克,常旭,张金淼,陈宝书,李鹏,李学聪
地球物理学报 , 2012, DOI: 10.6038/j.issn.0001-5733.2012.03.031
Abstract: 地震勘探中多次波的存在会影响速度模型的建立、地震成像效果、反演和解释过程中的介质属性提取等,因此多次波的压制成为至关重要的研究课题.本文采用改进的1范数匹配滤波法,基于1范数对大值条件的开放性,利用预测出的多次波模型Hilbert变换道及求导道,从理论上克服2范数的大值条件,并改善常规1范数下的正交性条件,在一次波和多次波叠合之处及能量差异大的情况下有效压制多次波.模型及南海深水盆地实际海洋地震数据的处理结果显示了改进的1范数匹配方法在压制多次波方面相对于常规2范数、1范数的优越性.
江西万载兴源冲铜矿流体包裹体地球化学研究
Geochemical Study of Fluid Inclusions from Xingyuanchong Copper Deposit in Wanzai, Jiangxi Province
 [PDF]

, , 王伟
Nuclear Science and Technology (NST) , 2014, DOI: 10.12677/NST.2014.22003
Abstract:
万载兴源冲铜矿地处宜丰景德镇板缘深断裂带西段黄茅地区。本文在前人研究基础上,通过对不同矿体矿石中的石英、方解石等脉石矿物进行系统的流体包裹体测温工作,来探讨矿区成矿流体来源。流体包裹体测温得出包裹体均一温度在75~440之间,主要分布于两个温度区间:110~190210~290,显示中低温的特征;盐度变化范围在1.74 wt%~22.58 wt%之间,显示中高盐度的特征。根据均一温度盐度图可以看出矿床成矿流体大致以海底喷流热液和与成岩作用有关的水为主,也有小部分岩浆热液的混合
Xingyuanchong copper deposit at Wanzai is located in the west section of Yifeng-Jingdezhen deep faults—Huangmao. On the basis of previous researches, and by carrying out temperature measurement of fluid inclusions systematically on gangue minerals, such as quartz and calcite, the authors discussed the sources of metallogenic fluids. The results show that 1) the homogenization temperatures of fluid inclusions vary in the range of 75?C~440?C, mainly in two sections: 110?C~ 190?C and 210?C~290?C, showing the feature of low medium temperatures; 2) the salinity ranges from 1.74 wt% to 22.58 wt%, suggesting medium high salinity. The homogenization temperature- salinity figure indicates the metallogeinic fluids are mainly submarine extrusive hydrothermal fluids and fluids related with diagenesis, and a small part of magmatic fluids.
基于LMDI的江苏省能源消费总量增长效应分析
,,龙如
资源科学 , 2010,
Abstract: 2002年以来,随着江苏省经济的快速发展,能源消费总量增长速度逐步加快,而省内能源供给远远小于需求,能源保障势必影响江苏省经济的可持续发展。因此,为全面分析江苏省能源消费增长的影响因素,本文从六大行业的能源消费入手,采用LMDI模型把江苏省1996年-2008年能源消费总量的增长的效应分解为生产效应、结构效应和强度效应。效应分解与分析结果表明:生产效应是促进能源消费增长的最主要因素,而强度效应对能源消费增长的抑制作用是江苏省近年来能源消费增长放缓的主要原因,结构调整带来的结构效应对能源消费增长的抑制作用还
蜂蜜中红霉素残留量的检测
韩南,
食品科学 , 2003,
Abstract: ?本文规定了薄层色谱法检查蜜蜂中的残留红霉素,利用固相萃取原理对蜜蜂中红霉素进行提取,其检测限度可达5mg/kg,对于把握蜂蜜的质量提供了简单、快速、方便而又经济的检测方法。
高职扩招背景下教学模式改革探索和研究——以线上线下教学为例
Exploration of Teaching Model in the Settings of Enrollment Expansion of Million Students in Higher Technical and Vocational Colleges—Taking On-Line and Off-Line Teaching as an Example
 [PDF]

,
Advances in Social Sciences (ASS) , 2019, DOI: 10.12677/ASS.2019.88207
Abstract:
高职大规模扩招为当前高职教育带来了巨大的机遇和挑战,特别是在教学模式方面。由于此次扩招的社会人员会存在学习基础参差不齐、学习时间和精力有限及学习课程内容过多等问题,因此,本文拟探讨线上线下教学方法在扩招背景下课程教学模式上的应用。线上主要通过MOOC (Massive Open Online Courses,大规模在线开放课程)教学,线下通过实验课教学,注重技能训练,德技并修,争取在扩招的同时做到教学资源不稀释,培养质量不下滑,助力更多青年凭借一技之长实现人生价值。
A large scale of enrollment expansion in higher technical and vocational colleges brings vast op-portunity as well as challenges to the education in higher technical and vocational colleges, espe-cially in teaching mode. The social members in this enrollment expansion might have the prob-lems in different basis, limited time and energy, and too many contents in learning; thus, this ar-ticle tries to explore the application of on-line and off-line teaching methods in the teaching mode in the settings of enrollment expansion. On-line teaching is about MOOC teaching, and off-line is mainly about experimental teaching, which lays emphasis on skills practice, pays attention to both moral and skills, so as to ensure the teaching resources and quality, facilitating more and more youths realizing their life values.
高产优质小黑麦新品种——中饲237
,孙元枢
麦类作物学报 , 2001, DOI: 10.7606/j.issn.1009-1041.2001.03.081
Abstract: 中饲237是用冬性小黑麦不育系与小黑麦品系杂交,经轮回选择选育而成的粮饲兼用型小黑麦新品种,具有植株高大、分蘖力强以及高产、优质、抗病、抗寒、耐旱、适应性广等突出特点。1998年通过全国牧草品种审定委员会审定、定名;1997~1999年全国累计种植面积近10万hm2。1 主要特征特性1.1 丰产性好 中饲237植株高大,分蘖力强,丰产性好。在1992~1994年的品比试验中,3年平均,每公顷鲜草产量为47.12t(吨),比对照品种固安大麦增产44.7%;干草产量为14.48t,比对照增产50.9%;籽粒产量为3784kg,比对照增产…
MLS66重载-高频加载下沥青路面应变行为分析
, 叶奋
中国公路学报 , 2014,
Abstract: ?为考察半刚性基层沥青路面在超重高频动载及环境温度交互作用下的力学响应状况,采用MLS66在高温及常温条件下进行半轴超载50%的足尺加速加载试验。结合加载次数、温度、模量等参数,分析了可控荷载条件下路面结构层底部三向瞬时及累积应变响应的空间分布及时程变化,并对实测值与计算值进行了对比分析。结果表明:面层底部瞬时应变实测值大于计算值,基层中两者较吻合;纵向瞬时应变比为1/5~1/2,且温度越高,应变比越小;高温下瞬时应变幅值为常温下的2~6倍;面层纵向应变温度系数约为横向的2倍,基层(底基层)的三向应变温度系数大致相同;瞬时应变幅值和应变温度系数与路面深度分别呈幂指数、负线性关系;加载次数与累积应变、地震波模量呈双对数线性关系,可用于沥青面层疲劳预估。
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