碱熔-离子色谱法同时测定玻璃中的氟和硫

玻璃样品中加入氢氧化钠,在700℃马弗炉中加热熔融,热水浸提,所得溶液通过OnGuardⅡAg/H柱后上机测定,消除加入的氯和碱的干扰,再经IonPac AG14柱和AS14柱分离,采用小体积的定量环直接进样,离子色谱法测定氟离子和硫酸根的含量。氟离子和硫酸根的线性范围分别为0.1～2μg/mL和0.5～20μg/mL,方法检出限氟为2.0 mg/kg和硫为1.0 mg/kg,测定结果的相对标准偏差(RSD)小于5.0%。实际玻璃样品用离子色谱法和化学法测定,两种分析方法的结果无显著性差异。     

离子色谱法同时测定天然碱矿中氯离子和硫酸根离子

通过测定氯离子和硫酸根离子可以确定天然碱矿中石盐和芒硝的含量,目前分析方法比较少,且流程冗长,容易污染,生产效率低。本文建立了离子色谱-抑制电导法测定天然碱矿中氯离子和硫酸根的分析方法。样品中水溶性阴离子经热水溶解进入溶液,以30 mmol/L氢氧化钾溶液作为淋洗液,利用AG19阴离子保护柱、AS19阴离子分离柱分离样品中的氯和硫酸根,CRD 200碳酸盐消除装置去除了碳酸根的干扰。方法检出限氯离子为0.01 mg/L,硫酸根为0.02 mg/L;加标回收率为100.9%～104.1%;精密度(RSD,n=10)小于2.5%。实际样品分析结果与滴定法的测定值基本吻合。本法操作简单,重现性好,灵敏度高,结果可靠,不受样品复杂组分及形成缓冲溶液体系的干扰,很好地解决了传统方法费时、耗材、不能同时测定氯离子和硫酸根的问题。     

固体聚合膜电解浓集法测量天然水中低含量氚的化学淬灭效应研究

固体聚合膜电解浓集法是浓缩氚含量较低(1 Bq/m~3)的天然水样的常用方法,但因水样自身含有杂质离子或电解装置聚合膜带入杂质进入浓集液,使浓集液偏酸性,在测量过程中易产生化学淬灭效应,导致氚的测量值偏低。本文研究了水样自身存在的杂质离子和聚合膜上残留的杂质离子、样品溶液的pH值及其电导率所产生的化学淬灭效应的影响,实验表明,为减少化学淬灭效应,提高测量低含量氚的准确性,需保证水样溶液呈中性,电导率≤1μS/cm,同时避免杂质沉积在聚合膜上。如果水样溶液的pH值偏酸性、电导率大于1μS/cm,可采用酸碱混合型离子交换树脂去除水样中自身的杂质;对于聚合膜引入的杂质,可在电解后的水样中加入微量氨水将其pH值调节至中性。     

阴离子树脂预处理-离子色谱法测定核纯氢氧化锂中阴离子杂质

采用氨型弱阴离子交换树脂预先对核纯氢氧化锂溶液转型,消除核纯氢氧化锂溶液中的游离氢氧根基体,转型后的溶液采用阴离子色谱法同时测定杂质氟离子、氯离子和硫酸根离子。该方法获得的氟离子、氯离子和硫酸根离子加标回收率优于90%,对应检出限分别为:5.0μg/g、 11.0μg/g和24.0μg/g。     

用EDTA间接滴定法测定冰雪水样中硫酸根离子含量问题的探讨

目前测定硫酸根离子较常用的方法是EDTA间接滴定法。该法适用于测定硫酸根含量较低的样品。冰雪水样中硫酸根离子含量很低,因此我们选用了此法。但在测定过程中,发现有个别样品尽管严格操作,但计算出的硫酸根含量却为负值,这显然是错的。现就这一问题作如下讨论。     

两次电导率测量法测定某些污染水中的硫酸根离子

配制两份配同体积的样品溶液,一份不加ＢａＣｌ２,另一份加过量的ＢａＣｌ２,根据两份溶液电导率的差值与硫酸根离子浓度之间的关系。建立了测定ＳＯ＾２－４的测定,其ＲＳＤ为≤２．１２％,加标回收率为９７．４％－１０３．９％。方法简单快速。     

离子色谱法测定矿物包裹体液相成份中的阴离子

气液包裹体存在并密闭于各种成因的矿物中,是天然的成矿溶液的样品.气液包裹体体积小(一般在几个微米以下)、组份复杂、含量极微.要分析这么小的包裹体成份,用一般分析方法是困难的,需采用进样量少、灵敏度高的分析测试手段.国内多采用比色法,比浊法、电化学等方法测定包裹体液相成份中的阴离子.我院以前采用的是离子选择电极法测定包裹体液相成份中的氟离子、氯离子;比色法间接测定硫酸根离子.这些方法都不能将氟、氯、硫酸根等离子一次同时分析出来,而且分析流程长、测定灵敏度还满足不了包裹体液相成份中阴离子的分析要求.     

离子选择电极连续测定地质样品的氯溴碘

1 干扰及其消除 地质样品中Cl~-含量远大于Br~-和I~-,因此离子选择电极法测定Cl~-时可忽略Br~-和I~-对其影响。但I~-对Br~-的测定有影响,可加入KMnO_4溶液将I~-氧化为高价而消除之。S~(2-)的干扰也可加入KMnO_4溶液使之被氧化为高价离子而消除。其它干扰在操作中已被分离。最终,在25ml体积中,1mg Cl~-不干扰20μg Br~-,40mg Cl~-和1.2mg Br~-不干扰10μI~-的测定。 在测定Cl~-和Br~-含量之后的溶液中,加入     

微波消解-离子选择电极法测定植物样品中氟离子的实验条件优化

准确检测植物体内的氟含量有助于预测氟化物的生态环境效应。植物中的氟含量低,通常不超过300μg/g,应用离子选择电极法测量氟需选择样品分解效率高的前处理方法使氟不受到损失,获得离子成分简单、空白低的溶液,同时加入适量的缓冲液增强氟离子的强度和掩蔽干扰。本文采用微波消解法处理植物样品,离子选择电极法测定氟的含量,通过优化实验条件确定了缓冲液的浓度。结果表明,在25℃、p H=6.5的样品溶液中加入147 g/L总离子强度缓冲溶液(TISAB)10 m L,避免了溶液中的阳离子与氟离子生成稳定的不溶絮状物,显著降低了沉淀物的产生。本方法检出限为0.242μg/g,精密度(RSD)小于8.5%,回收率为92.0%~108%,能满足地球化学样品分析中对植物样品中低含量氟的检测要求。     

地下水和土壤中不同形态碘的分离测定

实验选用717强碱型阴离子树脂吸附溶液中的碘离子和碘酸根,用30g/L氯化钠溶液和2.0mol/L硝酸钠溶液先后从树脂上洗脱碘酸根和碘离子,达到不同形态碘分离的目的。洗脱液用碘-淀粉比色法测定碘的含量。方法已用于我国高碘地区地下水和土壤样品中不同形态碘的分析。     

Unity of the national and the international in the socio-cultural development of the peoples of the USSR

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.     

Global repeating events in the history of the Earth and the motion of the Sun in the Galaxy

Chronological analyses of correlations between certain global repeating events (mass extinctions of marine organisms, meteorite impacts, and flashes in the frequency of geomagnetic reversals) during the Phanerozoic Eon and the motion of the solar system in the Galaxy are presented for five rotationally symmetrical models for the regular Galactic gravitational field. Thirteen of sixteen mass-extinction events can be described by a repetition interval of 183±3 million years. This is in agreement with the anomalistic period (interval between two subsequent passages of the Sun through the apocenter of its Galactic orbit) in the model of Allen and Martos. The positions of the minima and maxima in Gaussian functions approximating the frequency distribution for geomagnetic reversals also agree with the times of passage of the Sun through the apocenter and pericenter, respectively, of its Galactic orbit in this model. The maximum in the distribution of the deviations of the dates of mass extinctions from the nearest dates of impacts of large, crater-forming bodies is close to zero, providing evidence that many such events are correlated. As a rule, extinctions follow impact events. The impacts of large bodies have occurred most often when the solar system passes through the Galactic plane, while mass extinctions occur more often at some distance from the Galactic plane (about 40 pc). As a rule, intervals of increases in the frequency of geomagnetic reversals coincide with dates of impacts of large bodies. At the same time, these intervals do not show a clear correlation with the dates of mass extinctions. The intensity of mass extinctions, like the energy released by impacts, is consistently higher in periods when the Sun is moving from the apocenter toward the pericenter of its orbit, than when it is moving from the pericenter toward the apocenter. Thus, there is evidence for a variety of relationships between repeating global events in the Phanerozoic and the motion of the Sun in the Galaxy. Long-period variations in the frequency of geomagnetic reversals are correlated with the orbital motion of the Sun, and increases in the frequency of geomagnetic reversals are correlated with impacts. Mass extinctions are correlated with the impacts of large bodies, whose motions may have been perturbed by clouds of interstellar material concentrated toward the Galactic plane and by the shock front associated with the Perseus spiral arm, through which the solar system passes. The velocity of the Sun relative to the spiral pattern is estimated.     

Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth

It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T ₃ = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.     

从榴辉岩与围岩的关系论苏鲁榴辉岩的形成与折返

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。     

某高速公路下伏煤矿采空区稳定性分析

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。      

摩擦桩基桩土间极限摩阻力取值问题探讨

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。     

The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads

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.     

Paleomagnetic implications on the evolution of the tethys belt from the atlantic ocean to the pamirs since the triassic

We first re-examined the apparent polar wander curves for stable Eurasia and Africa since the Triassic. These curves were then combined together with curves of North and South America according to the kinematics of the Atlantic ocean and a synthetic polar wander curve was given. Then, most of the paleomagnetic results from the Tethys mobile belt, from the Atlantic to the Pamirs, were analysed.Several groups of plates, microplates and blocks can be seen. First, relatively stable regions like Maghreb and Sicily, which have not moved much. Then we have a group formed by Iberia, Sardinia, Italy and, to a lesser extent, Corsica and the Western and Central Alps. For these blocks, movements are anticlockwise rotations chiefly driven by the anticlockwise rotation of Africa, but they are sometimes stronger.To the east, a major change takes place. The north of the Aegean Sea and the Ionian zone are clockwise rotated and these rotations are recent: Oligocene-Miocene for the first part, Pliocene to the present for the second part.A major problem arises in Turkey, Caucasus and Iran. Paleomagnetic results indicate a position far to the south of Eurasia, and, at the same time, geological evidence is in favour of a position close to Eurasia. We discuss these discrepancies.