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1.
机械工业第六设计研究院原隶属于机械工业部,为事业单位,2000年10月转制后隶属于中国机械装备(集团)公司,为企业单位。该院现有在职员工459人,外聘人员300人,离退休人员356人,其中,中国工程院院士1人,中国工程设计大师2人,教授级高级工程师50人,高级工程师近260人,工程师300多人。该院是工业和民用建筑设计双甲级单位,并具有甲级工程总承包和工程监理资质。建院五十多年来,该院先后完成了5000余项大中型工业和民用建筑项目的设计和咨询,为我国国民经济建设和发展做出了卓越贡献。  相似文献   

2.
Summary Baotite occurs in the Garaoulére orebody, at Pierreftte, France, as an accessory mineral, included in alstonite and celsian, and associated with sphalerite, galena, pyrite, siderite and calcite in hydrothermal veins crosscutting calcareous, rutile-bearing, siltstones. Microprobe analyses revealed high W03 concentrations (up to 6 wt.%) in baotite. The empirical formula of W-rich baotite is Ba3.959Ti4(Ti3.169W0.393Fe0.116Al0.073 Cr0.048Nb0.024)3.823 Si4.05O28Cl1.166. The excess of charges due to the presence of W6+ and Nb5+ is compensated by the introduction of M3+ (Fe, Al, Cr) into Ti-octahedra, by the appearance of Al in Si-tetrahedra (for W-poor baotite) and by the appearance of vacancies in Ti-octahedra (3Ti4 -> 2W6+ + and in Ba-sites (Ti4+ Ba2+ W6+, ). The unit-cell parameters of W-rich baotite are: a = 19.92(2), c = 5.930(8) Å. Niobium-rich baotites (Baiyun-Obo,Semenov et al., 1961; Karlstein,Nmec, 1987) are characterized by substitutions: Ti4+(VI), Si4+(IV)Nb5+(VI), Al3+(IV) and 2Ti4+, Ba2+ 2Nb5+, .
Wolfram führender Baotit von Pierrefitte, Pyrenäen, Frankreich
Zusammenfassung Baotit kommt in dem Garaoulére Erzkórper in Pierrefitte, Frankreich als ein akzessorisches Mineral in Einschlÿussen in Alstonit und Celsian vor. Er ist mit Zinkblende, Bleiglanz, Pyrit, Siderit und Calcit assoziiert. Diese Paragenese ist an hydrothermale Gänge gebunden, die kalkige rutil-führende Siltsteine durchsetzen. Mikrosondenanalysen zeigen hohe W03 Gehalte (bis zu 6 Gew.%) in Baotit. Die empirische Formel von wolfram-reichem Baotit ist: Ba3.959Ti4(Ti3.169W0.393Fe0.116Al0.073Cr0.048Nb0.024)3.823 Si4.05O28Cl1.66. Der durch die Anwesenheit von W6+ und Nb5+ erforderliche Ladungsausgleich ergibt sich durch das Eintreten von M3+ (Fe, Al; Cr) in Ti-Oktaeder, und von Al in Si-Tetraeder (für W-armen Baotit) und schließlich durch das Erscheinen von Leerstellen in Ti-Oktaedern (3Ti4+ 2W6+ + und in Ba-Stellen (Ti4+, Ba` W6+, Die Zellparameter von ldW-reichem Baotit sind: a = 19.92(2), c = 5.930(8) Å. Niob-reiche Baotite (Baiyun-Obo, Semenov et al., 1961; Karlstein, Nmec, 1987) sind durch Substitutionen charakterisiert: Ti4+(VI), Si4+(IV)Nb5+(VI), Al3+(IV) und 2Ti4+, Ba2+ 2Nb5+, .
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3.
氯氧镁铝石(Koenenite)是一种少见矿物,最初发现于德国Gttingen。后来,F.里勒(F.Rinne)、R.库恩(R.Kühn)、H.-H.洛斯(H.-H.Lohse)、R.奥勒曼)R.Allmann)等人先后都作过报导,而在我国还是首次发现。氯氧镁铝石结构比较特殊,性质上是一个多变的矿物。  相似文献   

4.
CAAD(Computer Aided Architectural Design)在建筑设计专业工作中的应用技术称为计算机辅助建筑设计技术,它从上世纪60年代兴起80年代走红90年代席卷了整个建筑市场,并迅速成熟。设计师无疑已经离不开它们,代表作品有广为人知的AutoCAD、3DMAX,然而建筑师在享用它们的同时却不停的感慨它们的局限性:“它们把建筑设计引向机械的、单调的缺乏个性的死胡同……”,“建筑设计本身是一种模糊性设计,前期并不需要严格的定性定量,而且,美学问题是无法用定量的方法来描述的……”,它的呆板复杂与建筑师的灵性脱缰的思维无法合谐的同行,两者徘徊于等待与被等待之间隔岸对视。  相似文献   

5.
6.
Leucitities of probable late Pleistocene age from the extinct volcano of Gaussberg on the coast of East Antarctica consist of microphenocrysts of olivine, diopside, and leucite in a largely glassy groundmass. Their extreme K contents and K/Na ratios, as well as high Rb, Ba, and possibly Ti, are compatible with an origin by small degrees of partial melting of phlogopite-rich mantle below the level of amphibole stability, whereas their enrichment in P, Sr, Zr, Nb, La, Ce, Pb, and Th indicates the presence of minor phases such as apatite in the source material. Although the Mg/(Mg+Fe) values (0.70) and relatively high Ni and Cr contents suggest that the Gaussberg lavas represent near-primary melts, some degree of fractionation involving an aluminous phase (probably garnet) may be necessary to produce liquids with atomic K>Al. Alternatively, an as yet poorly understood process such as wall-rock reaction, liquid immiscibility, or mantle metasomatism may have been a critical factor in the genesis of these unusual rocks.Gaussberg is situated on a passive continental margin and does not appear to be related to any other known area of Cainozoic volcanic activity.  相似文献   

7.
8.
Metamorphism of the Gile Mountain Formation and Waits River Formation in the Strafford Dome and Townshend-Brownington Syncline in east-central Vermont records two nappe-style events, D1 and D2, followed by doming. D1 formed a muscovite + biotite ± ilmenite schistosity subparallel to compositional layering, SO, and was followed by heating to garnet grade. The temperature and pressure at the end of D1 are estimated to be c . 450 C and 6-8 kbar. D2 variably crenulated and folded S1 during a nearly isothermal pressure increase of 1-2 kbar, calculated from compositions of garnet, which have inclusions trails with progressive crenulation and rotation of the S1 fabric. Similar P-T paths are computed for most of the area, suggesting that the later schistosity developed during emplacement of a regional nappe 3-6 km thick. There is a general lack of D3 (dome-stage) microstructures.
Near the Strafford-Willoughby Arch, staurolite and kyanite overgrew S2 in pelites, and plagioclase with increasing X An overgrew S2 in calcic pelites, reflecting post-D2 heating to a maximum of 550-600 C. Metamorphic pressures at the end of D2 are fairly constant on the west side of the dome, indicating minor dome-stage uplift. In contrast, pressures at the thermal peak of metamorphism decrease by more than 4 kbar east of the dome. The observed pattern of isotherms and isobars is mainly the result of post-metamorphic, differential uplift and unroofing.
Finally, a minor, retrograde metamorphism produced the assemblage albite + epidote + K-feldspar + muscovite + chlorite, with grade increasing east toward the Connecticut River.  相似文献   

9.
Mollusks were studied from six sites in Lake Algonquin deposits (12,000-10,000 yr B.P.), five transitional (Lake Stanley low stage; 10,000 – 6000 yr B.P.), and six Nipissing stage sites (6000-4000 yr B.P.) east of Lake Huron in southwestern Ontario. The sites represent a variety of near-shore, lagoonal, estuarine, and fluvial environments. Eighteen species were limited to occurrences in Algonquin stage deposits; 8 were found only in the transitional age sites; and 14 species were restricted to Nipissing stage localities. With the possible exception of Goniobasis livescens, which occurred at five of the six Nipissing stage sites, the remaining stratigraphically limited species were usually restricted to one or two localities and probably cannot be used as zone fossils. Some cold-tolerant species (e.g., Anodonta grandis simpsoniana) were very early migrants into the study area, while others arrived later, apparently from eastern, southern, and western sources. Mollusks proved useful in paleoenvironmental reconstructions and to a lesser extent in biostratigraphic zonation.  相似文献   

10.
During the past 8000 years, large volcanic debris flows from Mount Meager, a Quaternary volcano in southwest British Columbia, have reached several tens of kilometres downstream in Lillooet River valley, with flow velocities of many metres per second and flow depths of several metres. These debris flows inundated areas that have become settled in the past 100 years and are now experiencing rapid urban growth. Notably, Pemberton, 65 km from Mount Meager, has doubled in size in the past five years. Approval of subdivision and building permits in Pemberton and adjacent areas requires assessment and mitigation of flood hazards, but large, rare debris flows from Mount Meager are not considered in the permitting process. Unlike floods, some volcanic debris flows occur without warning. We quantify the risk to residents in Lillooet River valley from non-eruption triggered volcanic debris flows based on Holocene landslide activity at Mount Meager. The calculated risk exceeds, by orders of magnitude, risk tolerance thresholds developed in Hong Kong, Australia, England, and in one jurisdiction in Canada. This finding poses a challenge for local governments responsible for public safety.  相似文献   

11.
Summary Louvain-la-Neuve, the sole Belgian New Town in three centuries, is located about thirty kilometers southwards of Brussels. In its first stage it had been established for welcoming most of the faculties of the Catholic University of Louvain (C. U. L.), which transferred from the original location in Louvain. The estate acquired by the C. U. L. mainly covers an agricultural area of 900 hectares, partly divided into 338 hectares for the future urbanized perimeter, 180 hectares for a public forest, and 163 hectares for a scientific park, designed for private research and development activities in connection with academic laboratories.The first part of the city center is almost completed and is located in the dale of the Malaise, on a substructure with underground parking and a railway station. Four neighbourhood units have been planned on the top of the slopes; the first two are already nearly finished and a third is under way. The principle of segregation of automobile and pedestrian traffic and its advanced architectural style constitute the main features.The active population of Louvain-la-Neuve now reaches about 12,000 (two-thirds are the students of the C. U. L.), and the residential population numbers more than 6,000 inhabitants (three-quarters are students and their families). The age structure is very young, due to the high proportion of students.Commuting to Louvain-la-Neuve is facilitated by excellent road and public transportation connections. As time goes by, it is anticipated that commuting will diminish. Moreover, a phenomenon of external commuting is developing. The attractive sphere and environment, the pedestrian areas and the emphyteotic system are the key features of the future residential development for persons neither professionally linked to the C. U. L. nor to the New Town.When the student transference is completed in 1979, the stage of real diversification of activities and functions will begin. About 20,000 inhabitants are scheduled for location by 1985 and a maximum of 50,000 by the end of the century. At that time, Louvain-la-Neuve together with its neighbours, Wavre and Ottignies, will form an urban tripole on a regional level, thereby strengthening the urban framework of the Walloon Brabant.  相似文献   

12.
Mineralogy and Petrology - The chemical composition of liandratite, U6+(Nb,Ta)2O8, was determined from material collected in Niobium, Yttrium, Fluorine type (NYF) pegmatites of the Karkonosze...  相似文献   

13.
Althausite occurs as cleavable masses in serpentine-magnesite deposits at Modum, Norway. The proposed formula in Mg2PO4 (OH0.37F0.25O0.10)0.81 with partly vacant halide sites. It is orthorhombic, space group Pna21, a = 8.258, b = 14.383, c = 6.054 A?, Z = 8. D(meas)=2.97, ?(calc) = 2.91 g/cm3 (X-ray), ?(calc) = 3.06 g/cm3 (Gladstone-Dale), H = 3 12 ?4. The strongest X-ray powder lines (41 given, Fe radiation) with intensities and indices are 3.593 (100)(040), 3.316 (90)(211), 3.024 (80)(002), 2.786 (60)(112), 2641 (60)(122).The mineral is light grey with vitreous lustre, running brown on alteration to apatite. Non-fluorescent. Perfect cleavage {001}, distinct cleavage {101}. It is biaxial positive, α=1.588, β=1.592, γ=1.598, 2Vγ(calc)=78.5°, negative elongation, X=b, Y=c, Z=a. IR, DTA and TGA data are given.  相似文献   

14.
Low‐pressure crystal‐liquid equilibria in pelitic compositions are important in the formation of low‐pressure, high‐temperature migmatites and in the crystallization of peraluminous leucogranites and S‐type granites and their volcanic equivalents. This paper provides data from vapour‐present melting of cordierite‐bearing pelitic assemblages and augments published data from vapour‐present and vapour‐absent melting of peraluminous compositions, much of which is at higher pressures. Starting material for the experiments was a pelitic rock from Morton Pass, Wyoming, with the major assemblage quartz‐K feldspar‐biotite‐cordierite, approximately in the system KFMASH. A greater range in starting materials was obtained by addition of quartz and sillimanite to aliquots of this rock. Sixty‐one experiments were carried out in cold‐seal apparatus at pressures of 1–3.5 kbar (particularly 2 kbar) and temperatures from 700 to 840 °C, with and without the addition of water. In the vapour‐present liquidus relations at 2 kbar near the beginning of melting, the sequence of reactions with increasing temperature is: Qtz + Kfs + Crd + Sil + Spl + V = L; Qtz + Kfs + Crd + Spl + Ilm + V = Bt + L; and Qtz + Bt + V = Crd + Opx + Ilm + L. Vapour‐absent melting starts at about 800 °C with a reaction of the form Qtz + Bt = Kfs + Crd + Opx + Ilm + L. Between approximately 1–3 kbar the congruent melting reaction is biotite‐absent, and biotite is produced by incongruent melting, in contrast to higher‐pressure equilibria. Low pressure melts from pelitic compositions are dominated by Qtz‐Kfs‐Crd. Glasses at 820–840 °C have calculated modes of approximately Qtz42Kfs46Crd12. Granites or granitic leucosomes with more than 10–15% cordierite should be suspected of containing residual cordierite. The low‐pressure glasses are quite similar to the higher‐pressure glasses from the literature. However, XMg increases from about 0.1–0.3 with increasing pressure from 1 to 10 kbar, and the low‐temperature low‐pressure glasses are the most Fe‐rich of all the experimental glasses from pelitic compositions.  相似文献   

15.
This paper explores the environmental conditions that faced the people of ancient Jawa during the Holocene, as well as previous prehistoric periods of the mid-late Pleistocene. Calcite speleothems in a lava tube are dated using the U-Th method, to marine oxygen isotope stage 7 from  250 to 240 ka and from  230 to  220 ka; and the stage 5/4 transition between  80 and 70 ka. The available evidence indicates general aridity of the Black Desert during most of the mid-late Quaternary, punctuated by short wetter periods, when the Mediterranean cyclonic systems intensified and penetrated the north Arabian Desert. These Mediterranean systems had a longer and more intense effect on the desert fringe closer to the Mediterranean and only rarely penetrated the Black Desert of Jawa. The results do not exclude some increase of rainfall which did not change water availability dramatically during the warm Holocene. The ancient Jawa city appears to have depended on technological ability to build elaborate runoff-collection systems, which became the prime condition for success.  相似文献   

16.
藏东西藏岩的电气石   总被引:2,自引:0,他引:2  
西藏岩是以发现地命名的一类新火成岩,相当于电英质火山岩。作为西藏岩最重要 造岩矿物之一的电气石,以其独特的产状、结构和构造等,显著有别于深成岩、交代岩和富电气石岩的电气石。所研究电气石产出的宏观、微观地质特征并借鉴富硼添加剂花岗岩体系 的岩石学实验资料表明,赋存在西藏岩内的电气石,大多数是由一类富硼和水的酸性岩浆- 热液过渡流体(但其总性质偏岩浆,即佤山岩浆),因近地表和内压大于外压,引发在一个较大而有限空间内隐爆、爆破,骤然冷凝结晶,并同石英及其晶屑一起胶结爆破角砾;佤山岩浆溢出期间,电气石与石英可各自聚集结晶并形成韵律状“层纹”。  相似文献   

17.
Shinozaki  Tetsuya  Sawai  Yuki  Ito  Kazumi  Hara  Junko  Matsumoto  Dan  Tanigawa  Koichiro  Pilarczyk  Jessica E. 《Natural Hazards》2020,103(1):713-730

Geological evidence of recent tsunamis from sediment samples collected from Lake Tokotan, a coastal lagoon in eastern Hokkaido, northern Japan, was detected using computed tomography (CT) and soft X-ray images, grain size, and radionuclide profiles. Initial field observations revealed that sediments had no discernable sedimentary structures at the top of the core. However, results of CT imaging, soft X-ray, and grain size analyses show evidence for three invisible sand layers that are intercalated with mud layers. These sand layers exhibit trends of landward fining and thinning. Furthermore, the distribution of sand layers was limited to the center and seaward parts of the lake. Vertical profiles of cesium and lead concentrations in combination with recent eyewitness accounts indicated that these sand layers are correlated with the 1973 Nemuro-oki, 1960 Chilean, and 1952 Tokachi-oki tsunami events. The deeper part of the sediment cores includes three volcanic ash layers and three prehistoric coarse sand layers. The prehistoric layers are correlated with unusually large tsunamis that were geologically identified in previous studies from eastern Hokkaido. These findings suggest that nondestructive techniques, in combination with radionuclide analysis, allow for detection of frequent but faint tsunami deposits. This technique allows for an improved understanding of the history of tsunami inundation in Lake Tokotan and of other locations for which stratigraphic evidence for faint tsunamis layers is not readily apparent from field assessments.

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18.
Abstract Chromian omphacite which contains up to 4 wt % Cr2O3 has been identified from low-grade metamorphic rocks in Nishisonogi, Kyushu, Japan. It occurs as aggregates, forming a thin horizon ([20 mm thick) in alayered metagabbro within a serpentinite melange zone, together with Cr-free omphacite, actino-lite, epidote and sphene. It may have been formed by the metasomatic introduction of Cr into the metagabbro from the serpentinite rather than by reaction with chromite. The structural formula, based on EPMA analyses, and the optical absorption spectrum of the chromian omphacite show that the Cr is positioned in the octahedral site.  相似文献   

19.
We describe the new mineral species titanium,ideally Ti,found in the podiform chromitites of the Luobusha ophiolite in Tibet,People’s Republic of China.The irregular crystals range from 0.1 to 0.6 mm in diameter and form an intergrowth with coesite and kyanite.Titanium is silver grey in colour,the luster is metallic,it is opaque,the streak is grayish black,and it is non-fluorescent.The mineral is malleable,has a rough to hackly fracture and has no apparent cleavage.The estimated Mohs hardness is 4,and the calculated density is 4.503 g/cm3.The composition is Ti 99.23-100.00 wt%.The mineral is hexagonal,space group P63 /mmc.Unit-cell parameters are a 2.950(2),c 4.686(1),V 35.32(5) 3,Z = 2.The five strongest powder diffraction lines [d in(hkl)(I/I0)] are: 2.569(010)(32),2.254(011)(100),1.730(012)(16),1.478(110)(21),and 0.9464(121)(8).The species and name were approved by the CNMNC(IMA 2010–044).  相似文献   

20.
Two Lateglacial insect sequences are described (a) from Conty, in the Selle valley and (b) from Houdancourt in the Oise valley, both in northern France. These investigations are part of a multidisciplinary investigation involving archaeology, sedimentology, geomorphology, geochronology and palaeontology (pollen, macroscopic plant remains, vertebrates, molluscs and insect fossils). The sequences of insect assemblages date from the latter part of the Bølling to the end of the Allerød periods. Environmental analysis of these faunas shows that rivers with riffles and pools meandered across flood plains. The river was extensively fringed with reedy vegetation. The only trees growing close to the river were of Salix and/or Populus. All the insect assemblages indicate that the thermal climates during the Bølling and Allerød periods were similar to one another and during both periods were very nearly as warm as that of the present day. No insect fossils were recovered from the sediments attributed to the Older Dryas interval though other evidence from these sites suggests that this event was decidedly colder than those immediately preceding and succeeding it. Comparisons are made between Lateglacial climatic patterns in northern France with those elsewhere in Europe.  相似文献   

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