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1.
Twelve rock chips and two samples of fines all have electronic absorption bands in diffuse reflected light between 0.32 and 2.5 micrometers. Major bands occur between 0.94 and 1.00 micrometer and at 2.0 micrometers, and arise from Fe(2+) in clinopyroxene and to a lesser extent in olivine. A band at 0.95 micrometer and other details of curve slope and shape for the lunar surface fines match McCord's telescopic curve for an 18-kilometer area that includes the Apollo-il site. Results confirm mineralogical predictions based on telescopic data and support the feasibility of obtaining mineralogical information by remote and in glass content. reflectivity measurements. 相似文献
2.
Turkevich AL Patterson JH Franzgrote EJ Sowinski KP Economou TE 《Science (New York, N.Y.)》1970,167(3926):1722-1724
Evidence has been obtained for a radioactive deposit on the lunar surface at Mare Tranquillitatis with a total intensity of 0.09 +/- 0.03 alpha disintegration per second per square centimeter. The presence of polonium-210 in amounts that are close to equilibrium indicates a continuous turnover rate of lunar material at this site of less than 0.1 micrometer per year. The lack of such a deposit at two other lunar sites suggests lower local concentrations of uranium there. 相似文献
3.
Crystals of armalcolite, Mg(0.5)Fe(0.5)Ti(2)O(5), up to several millimeters in length have been grown from a glass initially having the composition of lunar rock 10017. A single-crystal x-ray study has confirmed that the crystals are isomorphous with pseudobrookite and has shown that the cations are strongly ordered, with the Ti(4+) ions occupying the 8f sites and the Fe(2+) and Mg(2+) ions randomly distributed over the 4c sites. An examination of karrooite, MgTi(2)O(5), has revealed a similar distribution of Mg(2+) and Ti(4+) ions. A reexamination of earlier x-ray and M?ssbauer data for pseudobrookite, Fe(2)TiO(5), has shown that it is more consistent with this type of ordering than with the inverse structure that has been generally assumed. 相似文献
4.
A linear correlation between concentrations of Sm and ratios of Sm to Eu for nine lunar samples suggests that those samples could correspond to liquids from equilibrium partial melting of a common source. On the basis of partition coefficients in terrestrial systems, the fraction of melting would not have exceeded about 15 percent and the immediate source could have been composed of olivine, orthopyroxene, and opaque minerals plus at least 25 percent feldspar, with at most a few percent calcic clinopyroxene and less than 1 percent apatite. The large Eu depletions could also have been produced by fractional crystallization if the ratio of Eu(2+) to Eu(3+) in lunar magmas significantly exceeds the values for terrestrial magmas. 相似文献
5.
Site occupancy numbers for ferrous iron, magnesium, and calcium at the Ml and M2 sites in lunar clinopyroxenes are estimated from nuclear gamma-ray resonant absorption spectra of (57)Fe. The cation distribution is ordered; calcium and magnesium prefer M2 and Ml, respectively. The distribution corresponds to an equilibrium at a temperature lower than 680 degrees C. Crystals cleaved and sectioned by diamond-knife ultramicrotomy were examined by high-voltage (200 kv) electron microscopy and diffraction. Uniform 300-to 600-A-wide bands that correspond to single crystal domains were found. Correlation of the bands with magnetic ordering at low temperatures is considered. 相似文献
6.
Carter JL 《Science (New York, N.Y.)》1973,181(4102):841-842
A probable vapor-liquid-solid (VLS) type of growth has been discovered for the first time in nature on the surface of lunar rock 15015. Scanning electron microprobe and energy dispersive x-ray data indicate that the growth occurs as metallic iron stalks from about 0.015 to 0.15 micrometer in diameter, with bulbous tips consisting of a mixture of iron and sulfur and measuring from about 0.03 to 0.2 micrometer in diameter. The stalk length is two to ten times the bulb diameter. 相似文献
7.
Single-crystal x-ray diffraction, microprobe, optical and electron optical examinations of clinopyroxenes from Apollo 11 lunar samples 10003, 10047, 10050, and 10084 show that generally the crystals are composed of (001) augitepigeonite intergrowths in varying ratios. Transmission electron micrographs reveal abundant exsolution lamellae, many only 60 A thick. In addition to the phase inhomogeneities, primary chemical inhomogeneities are clearly demonstrated. There are reciprocal relationships between calcium and iron and between Ti(4+) + 2Ai and 2Si. Our evidence suggests that a chemically inhomogeneous subcalcic C2/c augite was the only primary pyroxene from which pigeonite later exsolved. 相似文献
8.
The spectral reflectivity (0.30 to 2.50 microns) of several lunar areas was measured with ground-based telescopes. A narrow absorption band centered at 0.95 micron was revealed for the first time. No other absorption bands appear in the spectrum. The reflectivity continues to rise at longer wavelengths throughout the spectral region studied. A comparison of the telescope measurements of an area 15 kilometers in diameter that includes Tranquillity Base with laboratory measurements of Apollo 11 soil samples reveals remarkable agreement, an indication that properties determined for fairly large lunar areas are relevant to local conditions. The spectra are interpretable in terms of surface mineralogy. The absorption band varies in both depth and shape and the overall slope of the curve changes with lunar area, an indication of differences in the composition and opacity of surface material. However, the lack of variety in the band position suggests there are no major differences (say, from mostly pyroxenes to mostly olivines) in the mineralogy at those sites studied. 相似文献
9.
Constituents of lunar soils and rocks were studied by powder and singlecrystal x-ray diffraction. In addition to identification of minerals, including rare amphibole, mica, and aragonite, a detailed study of the important rock-forming minerals of the plagioclase, pyroxene, and olivine groups has begun. M?ssbauer spectra were recorded from lunar soils, ground rock samples, and separates of iron-bearing minerals. The proportions of iron-bearing minerals were estimated from computer-fitted areas for the bulk samples. The Fe(2+) in the lower-density fraction of pyroxene was ordered, whereas that of the higher-density fraction was disordered. 相似文献
10.
A clast of spinel troctolite containing 8 percent cordierite (Mg(2)Al(4)Si(5)O(18)) has been identified among the constituents of Apollo 15 regolith breccia 15295. The cordierite and associated anorthite, forsteritic olivine, and pleonaste spinel represent a new, Mg-rich lunar highlands lithology that formed by metamorphism of an igneous spinel cumulate. The cordierite-forsterite pair in the assemblage is stable at a maximum pressure of 2.5 kilobars, equivalent to a depth of 50 kilometers, or 10 kilometers above the lunar crust-mantle boundary. The occurrence of the clast indicates that spinel cumulates are a more important constituent of the lower lunar crust than has been recognized. The rarity of cordierite-spinel troctolite among lunar rock samples suggests that it is excavated only by large impact events, such as the one that formed the adjacent Imbrium Basin. 相似文献
11.
A self-contained, hand-held radiometer designed for field use has been constructed and tested. The 4.5-kilogram device, consisting of a strap-supported electronics module and a hand-held probe containing three sensors, is powered by flashlight and transistor radio batteries, uses two silicon and one lead sulfide detector, has three liquid-crystal displays, features sample-and-hold radiometric sampling, and is spectrally configured to Landsat-D's thematic mapper bands TM3 (0.63 to 0.69 micrometer), TM4 (0.76 to 0.90 micrometer), and TM5 (1.55 to 1.75 micrometers). The device was designed to collect ground-truth data for the thematic mapper and to facilitate ground-based, remote-sensing studies of natural materials in situ. Prototype instruments were extensively tested under laboratory and field conditions, with satisfactory results. 相似文献
12.
Beryllium-10 (10Be) in excess of that expected from in situ cosmic ray spallation reactions is present in lunar surface soil 78481; its presence was revealed with a sequential leaching technique. This excess 10Be, representing only 0.7 to 1.1% of the total 10Be inventory, is associated with surface layers (<1 micrometer) of the mineral grains composing 78481. This excess 10Be and its association with surficial layers corresponds to (1.9 +/- 0.8) x 10(8) atoms per square centimeter, requiring a 10Be implantation rate of (2.9 +/- 1.2) x 10(-6) atoms per square centimeter per second on the surface of the Moon. The most likely site for the production of this excess (10)Be is the Sun's atmosphere. The 10Be is entrained into the solar wind and transported to the lunar surface. 相似文献
13.
Luminescence measurements were made of four lunar rocks, two terrestrial rocks (granite and gabbro), and one terrestrial mineral (willemite) by comparing the spectral curves with the curve of a barium sulfate standard. Efficiencies with 3000 angstrom excitation were < 6 x 10(-5) for the lunar samples, < 8 x 10(-5) for gabbro of very similar composition to the lunar samples, approximately 10(-4) for granite, and approximately 2 X 10(-2) for willemite. If these are typical values for other ultraviolet excitation wavelengths, the Apollo 11 site appears to contribute little to the observed lunar luminescence. 相似文献
14.
研究了施肥对一品红天鹅绒品种抗寒性的影响及可能的调控技术。采用三因素五水平二次回归正交旋转组合设计,建立了施K、Ca、Si量与天鹅绒抗寒指标综合分之间的效应模型,并对模型进行了统计选优,降维分析,边际效应分析。结果表明氯化钾、氯化钙、硅酸钠3种肥料均能提高一品红抗寒性,且重要性依次为:硅酸钠>氯化钾>氯化钙。氯化钾最大效应在600 mg/L,分别施氯化钙、硅酸钠0 mg/L;氯化钙最大效应为200 mg/L,分别施氯化钾150 mg/L,硅酸钠25 mg/L;硅酸钠最大效应为100 mg/L,分别施氯化钙、氯化钾0 mg/L;在同时施用3种肥的情况下,高浓度硅酸钠配合低浓度氯化钾、中等浓度氯化钙或高浓度氯化钾配合低浓度硅酸钠、中等浓度氯化钙有利于抗寒性提高。高抗寒性栽培要点为:施氯化钾量267~366 mg/L,施氯化钙量90~122 mg/L,施硅酸钠量24~52 mg/L。 相似文献
15.
Petrographic and electron-microprobe studies combined with high pressure-temperature investigations of phase relationships in average Apollo 11 basalt and possible source material show that the lower parts of maria may be composed of eclogite (density 3.74 grams per cubic centimeter), thus explaining the existence of mascons. The Apollo 11 basalt was probably formed at depths of 200 to 400 kilometers by a small degree of partial melting from pyroxenitic source material [FeO/(FeO + MgO) = 0.25, A1(2)O(3) 4 percent, CaO 3 percent]. This composition may be representative of the lunar interior and yields the observed mean lunar density and moment of inertia. Present data are in conflict with fission, binary planet, and capture hypotheses of lunar origin but are consistent with Ringwood's (1966) precipitation hypothesis. 相似文献
16.
17.
Muir AH Housley RM Grant RW Abdel-Gawad M Blander M 《Science (New York, N.Y.)》1970,167(3918):688-690
Lunar bulk sample 10084,85 (< 1 mm size dust), and samples from rocks 10017,17 (fine grained, vesicular), 10046,17 (breccia), 10057,59 (fine grained, vesicular, top surface), 10057,60 (fine grained, vesicular, interior), and 10058,24 (medium grained, not vesicular) have been investigated by (57)Fe M?ssbauer spectroscopy. Iron metal and the Fe(2+) minerals ilmenite, pyroxene, troilite, and iron containing glass have been identified. An iron line of sample 10084,85 (originally sealed in nitrogen) showed no significant intensity change when the sample was exposed to air. The antiferromagnetic transition in several lunar ilmenites at 57(0) +/- 2 degrees K corresponds to stoichiometric FeTiO,. Magneticallv separated 10057 showed troilite and somne metallic iron. 相似文献
18.
The measured reaction probability, gamma for the reaction of chlorine nitrate (CIONa(2)) with 60 percent (by weight) sulfuric acid aerosol increases monotonically with particle size at 250 kelvin. The reacto-diffusive length (l, the effective liquid depth over which reaction occurs) derived from these experiments is 0.037 +/- 0.007 micrometer (95 percent confidence level for precision). The reaction probability for the reaction of CIONO(2) with 60 percent sulfuric acid aerosol doped with approximately 7 x 10(-4) M hydrochloric acid at 250 kelvin is larger by about a factor of 4 than in the absence of hydrochloric acid and varies less with particle size (l = 0.009 +/- 0.005 micrometer). These results provide a test of the theory for gas-particle reactions and further insight into the reactivity of atmospheric aerosol. 相似文献
19.
Cruikshank DP 《Science (New York, N.Y.)》1969,166(3902):215-218
Infrared reflectance studies of small lunar regions reveal several absorption bands which match those of ferrous iron in laboratory spectra of olivines and orthopyroxenes. The craters Kepler and Aristarchus exhibit absorption bands suggestive of orthopyroxene, whereas the background mare material shows a band probably due to olivine. 相似文献
20.
水曲柳SRAP分子标记反应系统的优化 总被引：2，自引：0，他引：2
以水曲柳叶片DNA为模板,利用SRAP(相关序列多态性)技术及L_(16)(4~5)正交试验和单因子试验方法,分析了不同浓度的DNA模板、Mg~(2+)、dNTP、引物、TaqDNA聚合酶对扩增结果的影响,最终确立的PCR最佳反应系统为:20μL体系中,2×PCR buffer、DNA模板50～100ng,Mg~(2+) 的浓度2.0mmol/L,dNTP0.15mmol/L,引物0.30μmol/L,TaqDNA聚合酶1.0U;最佳退火温度50℃.在此反应系统下,所扩增谱带清晰、稳定、多态性高. 相似文献