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复杂高陡构造零井源距vsp资料常速度梯度射线追踪法vsp-cdp成像  [PDF]
梁向豪,罗斌,张新东
石油地球物理勘探 , 2014,
Abstract: ?以塔里木库车地区零井源距vsp地震资料为例,指出复杂高陡构造零井源距vsp已不属于一维地震范畴,即使上行反射得到准确的倾角时差校正,也无法充分体现复杂高陡构造零井源距vsp资料的全貌。首次采用复杂介质常速度梯度射线追踪技术对高陡构造零井源距vsp上行p波和上行sv波同时进行二维地震成像,展示了复杂高陡构造零井源距vsp模型数据及实际数据的处理效果,对类似地区零井源距vsp地震资料处理具有一定的实际参考价值。
长江流域沿江镉异常示踪与追源的战略与战术  [PDF]
成杭新,杨忠芳,奚小环,赵传冬,赵和苍,张建新,骆剑兰,唐将,刘英汉,庄广民,王文栋
第四纪研究 , 2005,
Abstract: 正在进行的多目标地球化学调查成果显示,长江流域存在全流域的Cd异常。长江流域Cd异常示踪与追源研究的长期目标是查明长江流域沿江各主要支流(汇水面积大于5000km2)Cd等重金属元素的物质来源、迁移形式和输入/输出通量、分辨自然源与人为源各自所占份额,建立沿江各支流Cd时空演化模型,监测它的未来发展趋势,对潜在生态效应进行预警预测;短期目标是针对Cd异常的重点地区,如长江源头、三峡库区、湘江流域、江淮流域、长江三角洲及流域内的4大淡水湖泊,查明Cd异常的来源,重建Cd异常形成的地球化学记录,评估可预见的将来(如10~50年)Cd异常的生态效应。
混合域三维vsp波动方程深度偏移方法  [PDF]
牟风明,王成礼,韩文功,王延光
石油地球物理勘探 , 2008,
Abstract: ?常规vsp成像方法利用vsp-cdp转换或基尔霍夫偏移,存在保幅性差及成像精度低等问题。混合域三维vsp波动方程深度成像方法是将vsp反射p波在深度域直接成像,利用分步傅里叶法在混合域进行波场外推,即在频率—波数域实现波场的相移,在频率—空间域实现时移校正。此法的优点在于能保持横向变速地质构造波动方程波场外推精度的同时提高计算效率。理论模型证明此方法可行,实际资料处理效果明显。
Optical properties of CdP2 and CdP4 nanoparticles incorporated into Na-X zeolite matrix  [PDF]
O. A. Yeshchenko,I. M. Dmitruk,S. V. Koryakov,Yu. A. Barnakov
Physics , 2004,
Abstract: For the first time nanoparticles of CdP2 and CdP4 semiconductors were prepared and studied. The nanoparticles were prepared by incorporation into zeolite Na-X matrix. Absorption and photoluminescence (PL) spectra of CdP2 and CdP4 nanoparticles were measured at the temperature of 77 K. Two bands were observed in both the absorption and PL spectra of CdP2 nanoparticles demonstrating the blue shift from the line of free exciton in bulk crystal. Single band was observed in both the absorption and PL spectra of CdP4 nanoparticles demonstrating the blue shift from the spectra of bulk crystal. We attribute the bands to some stable nanoparticles of CdP2 and CdP4 with size less than the size of zeolite Na-X supercage. We observed Stokes shift of the PL bands with respect to the absorption bands for both CdP2 and CdP4 nanoparticles.
vsp激发方式选择分析  [PDF]
范晓南,曹立斌,钟萍,文向东
天然气工业 , 2009,
Abstract: ?为满足实际生产对vsp资料的更高要求,除了加快采集设备和处理软件的更新外,激发方式也是一个不容忽视的重要问题。在川渝地区,长期以来都采用“水炮”作为震源来采集vsp资料,并且认为“水炮”激发方便、资料一致性较好,是vsp资料采集的理想震源,但是在川中、川中—川南过渡带上用水炮采集的vsp资料往往出现主频低、频带窄、波组不齐全的问题,在很大程度上影响了vsp技术的应用效果和推广。以bq205井vsp测井为例,对“井炮”和“水炮”激发采集的vsp资料从子波一致性、能量的稳定性、分辨率的高低等方面进行了对比分析,认为在低降速带较厚的地区,“井炮”激发采集的vsp资料比“水炮”激发的子波一致性要好、能量的稳定性更优、抗低频的能力更强、分辨率更高。这一结论对四川盆地vsp资料采集及其推广应用具有指导意义。
梯笼安全卡  [PDF]
地质与勘探 , 1975,
Abstract: 塔上无人操怍所配备的梯笼(罐笼,活动工作台),原来设计缺乏安全卡,容易出事故.为此,我们队制成一种梯笼两用安全卡,经使用证明,效果较好.此种安全卡,是由外管、压缩弹簧、安全卡(上部)、制功卡(下部)四部分组成(见附图).图左示安全卡的工作原理,图右示安全卡的安装情况.外管(6)用以连接安全卡和制动卡的上、下卡床(1)(9),其两端分别焊有支撑(12)
方位各向异性介质的VSP资料处理  [PDF]
方伍宝
地球学报 , 1996,
Abstract: 本文从理论上推导了二维EDA介质中的弹性波动方程,并对其进行了数值模拟,获得了当坐标系旋转30°时用点源激发的三分量波场切片及用相互正交的横波震源在同一位置激发,用两个相互正交的水平检波器接收的四分量全成记录。用双源四分量同时旋转方法对从两种EDA介质中采集的四分量作分析,得到了分裂的快,慢横波分量和它们间的时间延迟以及介质的裂隙方位角。从分离的快横波分量中提取反射能量,然后用VSP-CDP变换方法作成像处理。
不同时期追氮对冬小麦植株氮素积累及转运特性的影响  [PDF]
马冬云, 郭天财*, 岳艳军, 宋 晓, 朱云集, 王晨阳, 王永华
植物营养与肥料学报 , 2009, DOI: 10.11674/zwyf.2009.0203
Abstract: 采用盆栽和大田相结合,并应用15N示踪技术,研究了不同时期追氮对两个不同穗型冬小麦品种植株氮素积累及转运特性的影响。结果表明,成熟期小麦植株各部位氮素积累量和分配比例均表现为子粒>茎鞘+叶>根系或颖壳+穗轴;子粒中氮素积累量以拔节期追氮处理最高,氮素在子粒中的分配比例以抽穗期追氮最高,在根系中的分配比例则以全部底施处理最高。小麦植株吸收追施15N的比例为16.45%~26.6%,兰考矮早八和豫麦49-198分别以返青期追氮和拔节期追氮吸收的比例最高;子粒中氮素来自15N的比例均以返青期追氮最高,分别为27.16%和22.20%,但和拔节期追氮处理差异不显著。随着追氮时期推迟,氮的花后同化量、花后贡献率增加,而花前贡献率呈下降趋势;全氮对子粒贡献率表现为花前转运的贡献大于花后同化的贡献,但抽穗期追氮处理中,15N对子粒的贡献率表现为花后同化率大于花前转运贡献率。综合考虑子粒产量、蛋白质含量以拔节期追氮较为合适。
Fabrication, Study of Optical Properties and Structure of Most Stable (CdP2)n Nanoclusters  [PDF]
O. A. Yeshchenko,I. M. Dmitruk,S. V. Koryakov,M. P. Galak
Physics , 2005, DOI: 10.1016/j.physe.2005.07.019
Abstract: CdP2 nanoclusters were fabricated by incorporation into pores of zeolite Na-X and by laser ablation. Absorption and photoluminescence (PL) spectra of CdP2 nanoclusters in zeolite were measured at the temperatures of 4.2, 77 and 293 K. Both absorption and PL spectra consist of two bands blue shifted with respect to bulk crystal. We performed the calculations aimed to find the most stable clusters in the size region up to size of the zeolite Na-X supercage. The most stable clusters are (CdP2)6 and (CdP2)8 with binding energies of 9.30 eV and 10.10 eV per (CdP2)1 formula unit respectively. Therefore, we attributed two bands observed in absorption and PL spectra to these stable clusters. The Raman spectrum of CdP2 clusters in zeolite was explained to be originated from (CdP2)6 and (CdP2)8 clusters as well. The PL spectrum of CdP2 clusters produced by laser ablation consists of the asymmetric band with low-energy tail that has been attributed to emission of both (CdP2)8 cluster and CdP2 microcrystals.
四狗追戏问题的其他解法  [PDF]
朱晨
力学与实践 , 2000, DOI: 10.6052/1000-0992-f2000-058
Abstract: 本文通过直角坐标法及极坐标法求解四狗追戏问题.
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