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1.
对用Fe^3＋／Fe^2＋探讨庐山地区第四纪古温度的讨论 总被引：10，自引：0，他引：10
本文认为用Ｆｅ＾３＋／Ｆｅ＾２＋值推算庐山地区第四纪古温度是可行的，但认为在推算方法上必须严谨合理，文中论证了用Ｆｅ２Ｏ３／ＦｅＯ值代替Ｆｅ＾３＋／Ｆｅ＾２＋值推算古温度，且用少量样品的实验分析结果来划分庐山地区第四纪冰期和间冰期地层是欠妥的，其计算结果误差达０．４１－４．３５。据笔者采用容量法对庐山大校场部面１０个样品Ｆｅ＾３＋和Ｆｅ＾２＋含量的测试，发现这些样品反映的第四纪古温度值未有低达０℃ 相似文献
2.
催化动力学光度法测定痕量铁的研究 总被引：2，自引：0，他引：2
研究了在ｐＨ８．５的Ｎａ２Ｂ４Ｏ７－ＨＣｌ介质中,Ｆｅ＾３＋催化Ｈ２Ｏ２氧化茜素红褪色,建立了动力学光度法测定痕量Ｆｅ＾３＋的方法。方法检出限０．０４３μｇ／ｍｌ,线性范围０￣０．１７μｇ／ｍｌ,除Ｍｎ＾２＋、Ｃｏ＾２＋等离子外,其余共存离子基本无干扰,实测了天然水和化学试剂中痕量Ｆｅ＾３＋,结果满意。 相似文献
3.
氢化物—原子荧光法测定岩石中痕量硒的干扰及消除 总被引：12，自引：10，他引：12
用ＨＦ－ＨＣｌＯ４－ＨＮＯ３混合酸分解样品，采用Ｆｅ＾３＋作释放剂，研究了不同量的Ｆｅ＾３＋与ＨＣｌ酸度对Ｓｅ荧光强度的影响和干扰离子消除的效果，以及Ｆｅ＾３＋存在Ｔｅ存在下对Ｓｅ测定的影响。方法的检出限为０．０１μｇ／ｇ．样品中Ｓｅ量为０．１μｇ／ｇ的相对标准偏差（ｎ＝１１）是５．４％。用于岩石标样中痕量Ｓｅ的测定，结果较好。 相似文献
4.
对江汉盆地Ｔ油田主要的工业储层－下第三系新光沟嘴组沉积岩石的成岩流体进行了热力学研究。实测的成岩矿物流体包裹体的均一温度为１１０－１３９℃，属于该区中成岩阶段的温度范围（６７－１５５℃）。成岩流体的压力为１０．２－５６ＭＰａ。成岩流体中阳离子的活度出现Ｃａ＾２＋＞Ｍｇ＾２＋＞Ｎａ＾＋＞Ｋ＾＋＞Ｆｅ＾３＋＞Ｆｅ＾２＋；阴离子的活离出现ＨＣＯ３＾－＞ＳＯ４＾２－＞Ｆ＾－＞Ｃｌ＾－＞ＣＯ３＾２－；气相成 相似文献
5.
平顶村剖面古气候变化记录 总被引：6，自引：0，他引：6
对河北省阳原盆地平顶村剖面的野外观察,孢偻分析及＾１４Ｃ测年,作者认为,该剖面的地质时代为晚更新世晚期至全新世早期。依据Ｆｅ＾３＋／Ｆｅ＾２＋值估计温度并结合ＣａＣＯ３含量分析,该区自晚更新世晚期至全新切早期,古气候经历了温凉湿润→寒凉偏干→寒冷湿润→温冷干燥的变化过程; 相似文献
6.
提出了在同一份样品溶液中采用电位滴定法和库仑滴定法分别直接测定Ｆｅ＾３＋和Ｆｅ＾２＋的方法。在实验确定的最佳条件下测定０．２０－５．００ｍｇ Ｆｅ＾３＋的ＲＳＤ％小于０．９０（ｎ＝５）；测定０．０３２－１０．０ｍｇ Ｆｅ＾２＋的ＲＳＤ％小于０．８６（ｎ＝５）。用岩石一级标准物质和单矿物标准物质检验并参加标准物质ＧＳＲ７－１２的协作定值，结果良好。 相似文献
7.
8.
氢化物原子荧光光谱法测定化探样品中碲 总被引：4，自引：0，他引：4
研究提出了ＨＮＯ３和ＨＣｌＯ４分解样品,浓ＨＣｌ为还原剂,Ｆｅ＾３＋为减缓剂,氢化物－原子荧光光谱法直接测定化化样品中Ｔｅ的方法,检出限为０．０３５μｇ／ｇ。分析土壤等国家一级标准物质其结果与推荐值一致。 相似文献
9.
10.
新近在我国山西省娄烦县尖山铁矿的角闪片岩中发现一种取向连生的镁铁质闪石与钙质闪石共存对。电子探针分析确定它们分别为铁闪石Ｋ０．００１（Ｎａ０．０２７Ｃａ０．０７３Ｍｎ０．０３１Ｆｅ＾２＋１．８０１）１．９３２（Ｆｅ＾２＋２．９４８Ｍｇ１．９６４Ｔｉ０．００２Ａｌ０．０８７）５Ｓｉ８．０６９Ｏ２２．１０（ＯＨ）２与铁韭闪石（Ｋ０．１３５Ｎａ０．４６１）０．５９６（Ｎａ０．０８８Ｃａ１．８５３Ｍｎ０． 相似文献
11.
摩擦桩基桩土间极限摩阻力取值问题探讨 总被引：1，自引：0，他引：1
通过对广珠东线高速公路横沥大桥的试桩及土体的工程地质条件分析,总结出影响摩擦桩基桩土间极限摩阻力取值的一般问题以及解决问题的方法和措施。 相似文献
12.
位于华北和扬子两板块碰撞带中的苏鲁榴辉岩形成的温压条件不但是超高压，而且是高温。榴辉岩的PTt轨迹表明其为陆-陆磁撞俯冲带的产物。榴辉岩的区域性围岩花岗质片麻岩为新元古代同碰撞期花岗岩，榴辉岩及其他直接围岩皆呈包体存在于其中，并见新元古代花岗岩呈脉状侵入榴辉岩包体中。区域性围岩新元古代花岗岩的锆石中发现有柯石英、绿辉石等包裹体，表明新元古代花岗岩的组成物质也经受过超高压变质作用，且榴辉岩与围岩新元古代花岗岩的锆石U-Pb体系同位素年龄基本相同。但新元古代花岗岩所记录的变质作用和变形作用期次（或阶段）却少于榴辉岩。椐上述可得如下推断：超高压榴辉岩与新元古代花岗岩岩浆是同时在碰撞带底部（俯冲板块前部）形成的；榴辉岩的第一折返阶段是由新元古代花岗岩岩浆携带上升的，其第二折返阶段是和新元古代花岗岩一起由逆冲及区域性隆起而上升，遭受剥蚀。 相似文献
13.
The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads 总被引：3，自引：1，他引：2
Clemente Irigaray Francisco Lamas Rachid El Hamdouni Tomás Fernández José Chacón 《Natural Hazards》2000,21(1):65-81
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning. 相似文献
14.
某高速公路下伏煤矿采空区稳定性分析 总被引：10，自引：0，他引：10
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。 相似文献
15.
混凝剂处理钻井废泥浆液的研究 总被引：4，自引：0，他引：4
通过烧杯搅拌实验对混凝剂处理钻井废泥浆液进行研究,从混凝剂适应p H值范围、混凝效果、沉降速度三方面研究比较,找出一种较为理想的混凝剂,并分析了影响混凝剂性能的主要因素,确定了混凝剂的最佳投放剂量。 相似文献
16.
黄河源区水环境变化及黄河出现冬季断流的原因 总被引：12，自引：0，他引：12
自1954年有水文观测资料以来，黄河曾在青海省玛多县黄河沿水文站发生过3次断流。本文在分析黄河源区水环境特征及其影响因素的基础上指出，鄂陵湖、扎陵湖的环湖融区调节能力低，当遇到连续干旱、冬季其调节水量不足以维系黄河径流时便会发生断流，这是断流的主因。湖水位降低、开采沙金、过度放牧等自然和人为因素也会对黄河发生断流产生影响。鄂陵湖口附近黄河上修建的水电站开始蓄水，提高了两湖及环湖融区的调节能力，今后黄河冬季出现断流的可能性将大为降低。 相似文献
17.
Guboglo M. N. 《GeoJournal》1980,4(1):53-58
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen. 相似文献
18.
正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the 相似文献
19.
利用天山南坡科其喀尔冰川3号观测站2009年全年的气象观测资料,分析研究了科其喀尔冰川表碛区的小气候特征. 结果表明：总辐射和净辐射夏秋季较高、冬春季较低;反射辐射和地表反照率反之. 与其他地区不同,该区主要受积雪物理性质和下垫面状况的影响,冬春季地表反照率日变化表现为由大到小的变化过程,夏秋季表现为倒U型. 温度年变化表现为夏秋季高、冬春季低,最高月均值出现在8月,为9.4℃,最低月均值出现在1月,为-9.6℃. 受山谷风和冰川风的影响,全年的风向以西北风和西北偏西风为主,风向的日变化以11：00为界发生转向. 受降水和冰川消融等的影响,比湿夏秋季月均值较大,冬春季月均值较小. 相似文献
20.
Climate: Is the past the key to the future? 总被引：2，自引：0，他引：2
The climate of the Holocene is not well suited to be the baseline for the climate of the planet. It is an interglacial, a
state typical of only 10% of the past few million years. It is a time of relative sea-level stability after a rapid 130-m
rise from the lowstand during the last glacial maximum. Physical geologic processes are operating at unusual rates and much
of the geochemical system is not in a steady state. During most of the Phanerozoic there have been no continental ice sheets
on the earth, and the planet’s meridional temperature gradient has been much less than it is presently. Major factors influencing
climate are insolation, greenhouse gases, paleogeography, and vegetation; the first two are discussed in this paper. Changes
in the earth’s orbital parameters affect the amount of radiation received from the sun at different latitudes over the course
of the year. During the last climate cycle, the waxing and waning of the northern hemisphere continental ice sheets closely
followed the changes in summer insolation at the latitude of the northern hemisphere polar circle. The overall intensity of
insolation in the northern hemisphere is governed by the precession of the earth’s axis of rotation, and the precession and
ellipticity of the earth’s orbit. At the polar circle a meridional minimum of summer insolation becomes alternately more and
less pronounced as the obliquity of the earth’s axis of rotation changes. Feedback processes amplify the insolation signal.
Greenhouse gases (H2O, CO2, CH4, CFCs) modulate the insolation-driven climate. The atmospheric content of CO2 during the last glacial maximum was approximately 30% less than during the present interglacial. A variety of possible causes
for this change have been postulated. The present burning of fossil fuels, deforestation, and cement manufacture since the
beginning of the industrial revolution have added CO2 to the atmosphere when its content due to glacial-interglacial variation was already at a maximum. Anthropogenic activity
has increased the CO2 content of the atmosphere to 130% of its previous Holocene level, probably higher than at any time during the past few million
years. During the Late Cretaceous the atmospheric CO2 content was probably about four times that of the present, the level to which it may rise at the end of the next century.
The results of a Campanian (80 Ma) climate simulation suggest that the positive feedback between CO2 and another important greenhouse gas, H2O, raised the earth’s temperature to a level where latent heat transport became much more significant than it is presently,
and operated efficiently at all latitudes. Atmospheric high- and low-pressure systems were as much the result of variations
in the vapor content of the air as of temperature differences. In our present state of knowledge, future climate change is
unpredictable because by adding CO2 to the atmosphere we are forcing the climate toward a “greenhouse” mode when it is accustomed to moving between the glacial–interglacial
“icehouse” states that reflect the waxing and waning of ice sheets. At the same time we are replacing freely transpiring C3
plants with water-conserving C4 plants, producing a global vegetation complex that has no past analog. The past climates of
the earth cannot be used as a direct guide to what may occur in the future. To understand what may happen in the future we
must learn about the first principles of physics and chemistry related to the earth’s system. The fundamental mechanisms of
the climate system are best explored in simulations of the earth’s ancient extreme climates.
Received: 7 November 1996/Accepted: 23 January 1997 相似文献