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21.
材料研究与制备过程中的几个矿物学岩石学问题 总被引:4,自引:0,他引:4
在材料的研究与制备过程中往往会遇到很多有趣的矿物学、岩石学问题。这些问题有些是矿物学工作者和材料研究者所熟悉的,是材料研究者直接利用了矿物学工作者的研究成果。而有些问题是材料研究者首先发现,并将其中的某些条件加以利用,但缺少深入的矿物学理论研究;还有些工作是矿物学工作者得到的矿物学纯理论研究成果,但却不知如何应用到材料的开发与研究中。这就造成了介于矿物学与材料学之间的一个薄弱环节。这个薄弱环节为矿物、岩石工作者提供了一个广阔的研究领域和很多富有诱惑力的崭新的研究课题。于是一个新的分支学科———矿… 相似文献
22.
随着《地面气象观测新规范》和《OSSMO-HY2002》软件的正式启用,笔者就此软件与AHDM4.1在实际应用方面略作归纳整理。 相似文献
23.
Rivers in the Liaohe River Estuary area have been seriously polluted by discharges of wastewater containing petroleum pollutants and nutrients. In this paper, The Enhanced Stream Water Quality Model (QUAL2K) and its revised model as well as One-dimensional Tide Mean Model (1D model) were applied to predict and assess the water quality of the tidal river reach of the Liaohe River Estuary. Dissolved oxygen (DO), biochemical oxygen demand (BOD5), ammonia nitrogen (NH3-N) and total phosphorus (TP) were chosen as water quality indices in the two model simulations. The modelled results show that the major reasons for degraded rivers remain petroleum and non-point source pollution. Tidal water also has a critical effect on the variation of water quality. The sensitivity analysis identifies that flow rate, point load and diffuse load are the most sensitive parameters for the four water quality indices in the revised QUAL2K simulation. Uncertainty analysis based on a Monte Carlo simulation gives the probability distribution of the four water quality indices at two locations (6.50 km and 44.84 km from the river mouth). The statistical outcomes indicate that the observed data fall within the 90% confidence intervals at all sites measured, and show that the revised QUAL2K gives better results in simulating the water quality of a tidal river. 相似文献
24.
本文对新疆阿尔泰南缘乌吐布拉克铁矿区斜长花岗岩和黑云母斜长花岗岩进行了锆石LA-ICP-MS U-Pb年龄测定,分别获得了385.6±2.3 Ma(MSDW=0.13)和387.7±2.1 Ma(MSDW=0.23)的谐和年龄,两者为中泥盆世早期同源岩浆侵入体。乌吐布拉克铁矿的形成与岩浆侵入活动密切相关,据此限定铁矿成矿时代略晚于388~386 Ma,为中泥盆世早期成矿。乌吐布拉克斜长花岗岩与黑云斜长母花岗岩均具有高硅(SiO2=66.01%~79.14%)、富钠贫钾(Na2O>K2O)的特点。A/CNK〖HT4”〗{A/CNK=n(Al2O3)/\n(CaO)+n(Na2O)+n(K2O)]}值均小于1.1,表明两者为准铝质低钾花岗岩。微量元素表现为富集Th、Ta、Hf等高场强元素,亏损Rb 、Ba、K、Sr、P大离子亲石元素。稀土元素表现为轻稀土相对富集,轻重稀土元素分馏明显[(La/Yb)N=2.46~7.24],具有中等或强的Eu负异常。结合区域地质资料,认为乌吐布拉克矿区花岗岩形成于与板块俯冲有关的活动大陆边缘的陆缘弧环境中。 相似文献
25.
Polycyclic aromatic hydrocarbons (PAHs) contamination of topsoil in Benxi City, Northeast China was investigated in this study,
and sampling sites were located in industrial area and residential area. Results demonstrate that there is high variability
in the total PAHs concentrations, ranging from 783.00 ng/g to 729 076.29 ng/g dry weight in the topsoil of Benxi City and
the pollution in industrial area is the most serious. The results also present that higher molecular weight PAHs (4–6 rings)
contribute substantially (79.03%) to the overall content of PAHs. The PAHs sources were determined with factor analysis by
nonnegative constraints, and the results show that PAHs originating from traffic tunnel, power plant, coke oven and residential
emission sources, account for 27.10%, 40.81%, 20.11% and 11.98%, respectively, of the total. The PAHs pollution is the most
serious around Benxi Iron and Steel Group Corporation, and the PAHs mainly originate from coke oven and traffic tunnel, with
the average contribution rate of 57.40% and 42.60%, respectively. The source apportionment results are basically consistent
with the industry distribution, and the geographical and climatic characteristics of the study area. 相似文献
26.
新疆北山地区两个含铜镍镁铁—超镁铁质岩体铂族元素地球化学研究 总被引:2,自引:0,他引:2
对北山地区坡一和罗东含铜镍的镁铁-超镁铁质岩体铂族元素研究表明,两个岩体的铂族元素(PGE)总量较低,PPGE较IPGE富集,原始地幔标准化模式呈正斜率,均较原始地幔亏损,具Ir和Rh的弱负异常。较低的Pd/Ir比值表明岩石主要受岩浆作用控制,后期热液作用影响不明显。两个岩体的原生岩浆均为MgO 含量较高的PGE不亏损的拉斑玄武质岩浆,较高的Cu/Pd、Ti/Pd比值表明岩浆在演化过程中发生了硫化物的熔离。罗东岩体早期矿物相(橄榄石、铬铁矿)的分离结晶作用对岩浆中的硫达到饱和具有重要的贡献,而坡一岩体该作用对硫化物熔离的贡献不明显。坡一和罗东岩体的R值表明两岩体均具有达到中型Ni矿床的潜力。 相似文献
27.
Temporal and spatial variations in the discharge and dissolved organic carbon of drip waters in Beijing Shihua Cave,China 总被引:1,自引:0,他引:1
To detect the causal relationship between cave drip waters and stalagmite laminae, which have been used as a climate change proxy, three drip sites in Beijing Shihua Cave were monitored for discharge and dissolved organic carbon (DOC). Drip discharges and DOC were determined at 0 to 14‐day intervals over the period 2004–2006. Drip discharges show two types of response to surface precipitation variations: (1) a rapid response; and (2) a time‐lagged response. Intra‐annual variability in drip discharge is significantly higher than inter‐annual variability. The content of DOC in all drip waters varies inter‐ and intra‐annually and has good correlation with drip water discharge at the rapid response sites. High DOC was observed in July and August in the three years observed. The flushing of soil organic matter is dependent upon the intensity of rain events. The DOC content of drip water increases sharply above a threshold rainfall intensity (>50 mm d?1) and shows several pulses corresponding with intense rain events (>25 mm d?1). The DOC content was lower and less variable during the dry period than during the rainy period. The shape of DOC peak also varies from year to year as it is influenced by the intensity and frequency of rainfall. The different drip sites show marked differences in DOC response, which are dominated by hydrological behaviour linked to the recharge of the soil and karst micro‐fissure/porosity network. The results explain why not all stalagmite laminae are consistent with climate changes and suggest that the structure of the rainy season events could be preserved in speleothems. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
28.
29.
新疆阿尔泰南缘阿巴宫铁矿区康布铁堡组变质火山岩年龄及地质意义 总被引:15,自引:1,他引:14
阿尔泰南缘古生代康布铁堡组火山岩系是许多铁矿、铜锌矿以及铅锌矿的赋矿围岩。但赋矿地层目前还缺乏精确的同位素年代学资料。本研究应用SHRIMP锆石U-Pb定年法,获得阿尔泰南缘克朗盆地内阿巴宫铁矿区康布铁堡组地层中变质流纹岩的形成年龄为412±3.5Ma(MSWD=1.4),证明了阿尔泰南缘克朗盆地内泥盆纪早期存在着强烈的火山活动,与区内广泛发育的火山岩属于同一事件的产物,可能与同时代的花岗岩有相同的动力学背景。本项结果为研究阿尔泰南缘古生代构造演化及阿巴宫铁矿床成因提供了重要的依据。 相似文献