塔里木盆地柯坪-巴楚露头区白云岩成岩作用机理研究

Through field outcrop dolomite observation, laboratory petrography (macroscopy, microscopy, cathodeluminescence and scan electronic microscopy), geochemistry (carbon-oxygen-strontium isotopes and trace elements) and fluid inclusion microthermometry study in Keping-Bachu area of Tarim Basin, it can be inferred that there are existing eight dolomite texture types within four evolution phases in Keping-Bachu area of Tarim Basin. The paragenesis of different dolomite texture types and associated minerals in Keping-Bachu area has been established. The carbon and oxygen isotopes of saddle dolomites and matrix dolomites overlap greatly. The Strontium isotopes results of Keping-Bachu outcrop area show that the strontium isotopes differentiation of the matrix and saddle dolomites is not obvious, the reason of which is that there is thousands of Cambrian-Ordovician dolomite strata below the stratum bearing the saddle dolomite. In the process of the heat flow upward migration, the isotopes of the heat interacts with the host rock, which leads to the similarity betwwen the strontium of the saddle dolomite and matrix dolomite. The strontium isotope of the saddle dolomite is not very radiogenic. the six types samples within four phases in the study area show Eu negatively. Comparing to the other types of samples, the δEu of saddle dolomite is relatively high falling into the range of 0.510-0.874, which shows that the saddle dolomite forms in the hydrothermal setting and is affected by the hydrothermal activity to some extend.The Lan/Ybn of saddle dolomite is high up to 15.726, which means that the HREE is very rich. It belongs to the typical hydrothermal genesis model. The δCe of saddle dolomite is positive anomaly, which is the result of high effect from the land source debris. The homogeneous temperature of the saddle dolomite falls into two ranges 110-120℃ and 125-160℃, after pressure correction, they are 141-152℃，157.5-196℃, the salinity of the saddle dolomite can reach to 20-25%. With the comparing with the burial history, the Th of the saddle dolomite is high than the ambient strata temperature, these data show that the saddle dolomite is of hydrothermal origin. The evolution trend of different dolomite and associated minerals is from matrix dolomite, dolomite cementation, saddle dolomite, quartz to calcite. Alonging with this evolution trend, the temperature of the diagenetic flow initiated from 80-100℃, after rising to 135-160℃, then gradually declined. Finally, a structurally-controlled dolomitization model is established in Keping-Bachu area of Tarim Basin.

东灵山森林生态系统若干水分问题的研究

东灵山地区年均降水量659.7mm，单次降水以雨量小、雨强低的降水为主。水汽压（年均17.7mb）、相对湿度（年均66％）的季节变化呈现生长季高、冬季低的趋势。年均蒸发量1019.5mm;气温、风速、日照时间和水压与月蒸发量和日蒸量相关显著;气温、日照时间和水压分别在11-6月、7－8月和9－10月为决定蒸发量的首要因子。枯枝落叶层、土壤层湿度主要受前十日降水量和坡向影响。 植物体含水量生长季节较高，冬季较低;含水量随径级的增大而降低。六个灌木树种的平均含水量大小顺序为：毛榛（48.62%）最高荆条（36.32%）最低;七个乔木树种水分含量为油松，56.14%;蒙椴，54.19%;华北落叶松，52.91%;五角枫，43.64%;辽东栎，41.87%;棘皮桦，41.13%;大叶白腊，37.79%。几种植被类型的储水量为：辽东栎林，82.08mm;华北落叶松林，47.35mm;混交林，34.60mm;油松林，31.33mm;灌丛，12.40mm。各树种叶片日最低水势的季节均值为：辽东栎，-16.1bar;五角枫，-15.8bar;大叶白腊，-15.1bar;糠椴，-13.4bar;棘皮桦，-12.3bar;蒙椴，-12.2bar。叶片水势的日间变化均呈一“V”形曲线;光照在叶片水势的日间变化中起着决定性作用。 96年各树种平均单株树干茎流量为辽东栎，30.3mm(4.19%);华北落叶松，16.1mm(2.22%);油松，8.9mm(1.23%);棘皮桦，2.9mm(0.40%)。两个生长季各林分冠层的水量平衡为：辽东栎林，树干流茎量101.87mm(9.18%)，穿透降水量823.08mm(74.15%)，截留量185.05mm(16.67%);华北落叶松林，树干径流量66.88mm(6.03%)，穿透降水量836.92mm(75.40%)，截留量206.20mm(18.58);混交林，树干径流量50.13(4.52%)，穿透降水量846.78mm(76.29%)，截留量212.20mm(19.12%);油松林，树干径流量33.90mm(3.05%)，穿透降水量934.88mm(84.22%)，截留量141.22mm(12.72%)。多元回归分析表明，树干流茎量S与降水量P和前24小时降水量P_1呈显著正相关关系;穿透降水量T与降水量P和最大雨强M正相关显著。附加截留量与降水时间成正比。 枯枝落叶层的生物量为：油松林，25.56t/hm~2;华北落叶松林20.01t/hm~2;辽东栎林，8.31t/hm~2;混交林，7.98t/hm~2。枯枝落叶层的平均实际持水量和有效持水量均以油松林最大，其次是华北落叶松林，而混交林和辽东栎林较低;枯枝落叶层的实际持水量和有效持水量的季节变化分别与前十日降水量P10成正相关和负相关关系。枯枝落叶层的截留量为油松林＞华北落叶松林＞辽东栎林＞混交林;油松林（145.632mm和90.800mm）混交林(61.816mm和54.504mm)。油松林、辽东栎林、混交林和华北落叶松林去除枯枝落叶层后，土壤入渗量比对照平均降低100mm以上;表层土壤含水量分别比对照土壤下降了6.26、18.26、15.06和15.07个百分点。地表径流量分别增加了，辽东栎林34.299mm(603%)和15.816mm(525%);油松林14.593mm(732%)和10.584mm(1321%);混交林12.004mm(181%)和7.275mm(364%);华北落叶松林3.555mm(118%)，3.275mm(229%)。96年生长季，各土壤流失量分别增加了：油松林172.751t/hm~2(124倍);辽东栎林836.500t/hm~2(119倍);混交林172.499t/hm~2(47倍);华北落叶松林11.557t/hm~2(11倍)。表层土壤容重分别增加了：油松林15.0%和20.6%，辽东栎林18.4%和28.2%，混交林11.5%和38.5%，华北落叶松林4.3%和17.1%。 0-60cm深度土壤容重平均值的大小顺序为：草地>灌丛>辽东栎林>油松林>混交林>华北落叶松林;而土壤孔隙度的大小顺序为华北落叶松林>混交林>油松林>辽东栎林>灌丛>草地。两个生长季为土壤实际储水量的均值：油松林，124.45mm，78.62mm;辽东栎林，131.23mm，87.72mm;混交林，180.41mm，113.90mm;华北落叶松林，165.53mm，127.95mm;灌丛，172.50mm，89.81mm;草地，152.92mm，89.59 mm分别比干旱年份97年高出45.83mm、43.51mm、51.63mm、37.58mm、82.69mm和63.33mm。两个生长季的地表径流量为草地，30.930mm(2.79%);灌丛，16.321mm(147%);油松林，2.911mm(0.26%);辽东栎林，8.703mm(0.78%);混交林，8.625mm(0.78%);华北落叶松林，4.447mm(0.40%)。油松林、混交林和华北落叶松林地表径流量与降水量P(mm)和最大雨强(mm/h)正相关显著;而辽东栎林、灌丛和草地的地表径流量则与降水量P(mm)、平均雨强Q(mm/hr)和最大雨强M(mm/hr)三者之间呈显著正相关关系。与草地相比(1220.093kg/hm~2，100％)，灌丛、辽东栎林、混交林、油松林和华北落叶松林96年生长季的土壤流失量分别降低了85.05%、94.26%、96.99%、98.86和99.14%。 降水量是影响小流域径流量时间变化的主要因素;南沟和马牙石沟96年的径流量分别是97年的8.19倍和7.87倍，而径流深(46.25mm，52.75mm)分别比97年(5.65mm,6.70mm)高出40.60mm和46.05mm。两个小流域由于面积的差异而使南沟两年的径流量分别比马牙石沟高出2773.136m~3(13.15%)和235.434m~3(8.79%)。96年和97年马牙石沟径流深比南沟高出6.5mm(14.05%)和1.05mm(18.58%)。在地处大陆性季风气候区的东灵山地区，用0.010m~3/min/km~2/hr能较好地分割小流域的洪峰和基流。在五次暴雨水文曲线中，马牙石沟的快速径流量分别比南沟高出25.00%到143.33%。五次洪水水文响应R的平均值南沟为0.218%，马牙石沟为0.404%;与海洋性气候地区相比，东灵山地区小流域的R值要低一到两个数量级。马牙石沟洪峰流量Qp的平均值为418.772L/min要比南沟(281.191L/min)大48.9%。东灵山地区小流域的洪水径流过程可分为三种类型。

~(143)Dy和~(141)Dy的β缓发质子衰变与自旋指认

分析了143Dy和141Dy的β缓发质子衰变的数据,对比计算了这两种核的核位能面。从中看到了143Dy的衰变包括有1/2+基态和11/2-同核异能态的两种衰变成分,并且确定了它们的半衰期分别为(6.0±1.5)s和(3.0±0.5)s。同时也测定了141Dy的半衰期为(0.9±0.2)s,并指认了它的自旋宇称为9/2-。

~(140)Tb和~(141)Dy的β缓发质子衰变以及~(143)Dy的自旋宇称

利用40Ca+106Cd融合蒸发反应产生了近质子滴线核140Tb和141Dy,配合氦喷嘴带传输系统采用“质子-γ”符合方法观测了它们的β缓发质子衰变,其中包括半衰期、质子能谱和衰变到第二代子核不同低位态的分支比．通过统计理论拟合提取了140Tb和141Dy的基态自旋宇称分别为7±和9／2±．另一方面,用Woods-Saxon Strutinsky方法计算了这两种核限制组态的势能面,由此得到140Tb和141Dy的基态自旋宇称分别为7+和9／2-．此外用同一方法还计算了143Dy的核势能面,从中看出143Dy存在有自旋宇称为1／2+的基态和一个激发能为198keV的11／2-的同质异能态．该结果与2003年Eur．Phys．J． A16:347-351中的143Dy衰变实验数据相符．

~(141)Nd激发态的在束γ谱学研究

通过1 3 0 Te(1 6O ,5nγ) 1 4 1 Nd反应布居了1 4 1 Nd的高自旋态能级 .对反应产生的在束γ射线进行了γ射线单谱和γ -γ符合测量 .建立了激发能达 76 1 4 .5keV的1 4 1 Nd能级纲图 ,新发现了 1 2条γ射线和 1 5个能级 .基于实验测量的γ跃迁各向异性 ,建议了1 4 1 Nd部分能级的自旋值 .用一个h1 1 2 价中子空穴与1 4 2 Nd核芯晕态的耦合可以定性地解释1 4 1 Nd的能级结构

~(141)Nd中的粒子-核芯耦合

通过~(130)Te(~(16)O,5nγ)~(141)Nd反应研究了~(141)Nd的高自旋态。建立了激发能达7614.5keV的~(141)Nd能级纲图,新发现了12条γ射线和15个能级。用粒子-振子模型和半经验壳模型分别计算了~(141)Nd的集体和单粒子激发的能级位置。根据计算的能级位置以及实验测量得到的γ跃迁强度和多极性信息,讨论了~(141)Nd激发态的能级结构。

beta-delayed proton decays and spin assignments for Tb-140, Dy-141 and Dy-143

The proton-rich isotopes Tb-140 and Dy-141 were produced via the fusion evaporation reaction Ca-40+ Cd-106. Their beta-delayed proton decays were studied by p-gamma coincidence in combination with a He-jet tape transport system, and half-lives, proton energy spectra, gamma-transitions following the proton emission, as well as beta-delayed proton branching ratios to the low-lying states in the grand-daughter nuclei were determined. Comparing the experimental data with statistical model calculations, the ground-state spins of Tb-140 and Dy-141 were found to be consistent with 7 and 9/2, respectively. The configuration-constrained nuclear potential energy surfaces (NPES) of Tb-140 and Dy-141 were calculated using the Woods-Saxon-Strutinsky method, which suggest the ground-state spins and parities of Tb-140 and Dy-141 to be 7(+) and 9/2(-), respectively. In addition, the configuration-constrained NPES of Dy-143 were calculated, which predict a 1/2(+) ground state and a 11/2(-) isomer with excitation energy of 198 keV. These findings are consistent with our previous experimental data on Dy-143 reported in Eur. Phys. J. A 16, 347 (2003).