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71.
磷处理粉煤灰可作农业土壤磷源   总被引:2,自引:0,他引:2  
粉煤灰(简称CCP或ash)具有改良土壤,增加植物产量的功能。此外,由于它特殊的多孔结构,也可用作吸纳并承载植物养分的载体。用NaH2PO4配制成含磷0.10mol/L浓度的溶液,对采自加拿大西安大略省Sarnia地区Lambton电厂的底灰(bottomash)进行振荡浸渍处理。结果表明,振荡浸渍66h后的粉煤灰中磷含量可达784×10-6。以磷处理粉煤灰、未进行磷处理的粉煤灰和石英砂按比例混合,作为基本生长介质进行玉米种植实验,其中实验配方设计为生长介质中含磷量分别为标准含磷浓度(50×10-6)的10%、25%、50%、75%和100%。生长26、34和46d后分别与不含磷的空白配方、施加含氮-磷-钾为0-20-0标准磷肥并控制磷含量为标准浓度(50×10-6)配方进行生物产量对比。生长实验结果表明,以磷处理粉煤灰供磷的生长介质,当含磷量为标准浓度的25%至100%时,其植物生长量就比添加标准浓度磷肥的配方好。种植46d后的生物生长量统计结果显示,含磷分别为标准浓度50%、75%和100%的实验介质中,玉米杆的鲜重较施标准磷肥介质中玉米分别增长39.46%、42.73%和46.13%;玉米杆干重依次增加29.71%、13.39%和28.87%;根鲜重平均增加16.62%;根干重平均增加14.03%。上述实验结果启示,粉煤灰可以很好地吸纳承载磷养分,并持续供给植物吸收生长,如果采用吸纳磷(或其他养分)的粉煤灰改良砂质土壤将有重要意义。  相似文献   
72.
Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded that (l)the Songpan-Garze fold belt has uplifted at least by 3-4 km with an uplift rate of no less than 0.3-0.4 mm/a since 10 Ma B.P.; (2) the Longmenshan thrust nappe belt has uplifted at least by 5-6 km with an uplift rate of more than 0.5- 0.6 mm /a since 10 Ma B.P.; (3) the Longmenshan detachment belt has uplifted by 1 - 2 km at a rate of 0.016-0.032 mm/a since 60 Ma B.P.; (4) the West Sichuan foreland basin has uplifted by 1.7-3 km at a rate of 0.028-0.05 mm/a since 60 Ma B.P.; (5) the uplift rate of the area on the west side of the Beichuan-Yingxiu-Xiaoguanzi fault for the last 10 Ma is 40 times as much as that on its east side; (6) the uplifting of the the Songpan - Garze fold belt and the subsidence of the West Sichuan foreland basin 60 Ma ago exhibit a mirro-image correlation, i.e  相似文献   
73.
74.
目前,升降工序的价值约占钻探工作总价值的20%,所用时间占钻进深地质勘探孔的总时间的20-40%。使用自动化和机械化不能完全解决深孔钻进时提高效率的任务,因为  相似文献   
75.
使用能够在长时期鑽进中继续保持有效地尅取的正确结构的鑽头,是提高鑽粒鑽进生产效率的方法之一。现在所使用的鑽粒鑽头(ГОСТ6250-52)的主要缺点为:鑽头底部工作面积在鑽进中不断地增加和鑽头壁的厚度不够。这些缺点在很大程度上使得在使用这种类型鑽头鑽进时的囘次进尺较短。同时,由于鑽孔延深的缘故,增加每次囘次鑽进时间的问题在目前就更有重大的意义。  相似文献   
76.
正 As the Middle Triassic of China is generally fossiliferous only in its upper part, i. e., the Ladinic, the discovery of the Anisic fauna is interesting and it seems desirable to give an account of the remains. The material was collected  相似文献   
77.
新疆天山北部地区存在有石炭纪的埃达克岩-高镁安山岩-富Nb玄武质岩组合,并且其中许多岩石与铜(金)矿床伴生(如达巴特、阿希、土屋-延东、赤湖,等等)。埃达克岩富钠、高Sr但亏损Y与Yb,无明显Eu-正Eu异常以及正Sr异常与Nb、Ti亏损。高镁安山(闪长)岩是本次研究首次报道的,这些岩石无明显Eu-正Eu异常以及Nb、Ti亏损,普遍具有高的MgO和Cr、Ni含量,其中阿希金矿区一些样品类似于日本西南新生代Setouchi弧火山岩带中的赞岐岩类。富Nb玄武质岩富钠贫钾,具有微弱负.正Ba、Nb和Ti异常以及高的Nb/La比值,不同于大多数正常岛弧玄武岩。天山北部地区石炭纪埃达克岩具有高的8Nd(t)(+3.4-+9.0)和低的(^87Sr/^86Sr)i(0.7032—0.7043)。富Nb玄武质岩具有变化的εNd(t)(+3.6-+11.6)和(^87Sr/^86Sr);(0.7007—0.7067)。我们的研究表明,天山北部地区石炭纪埃达克岩-高镁安山岩-富Nb玄武质岩组合可能是“埃达克岩交代的岛弧岩浆岩系列”。埃达克岩最有可能由石炭纪北天山洋的年轻洋壳在俯冲过程中熔融形成。另外,俯冲板片产生的熔体以及所释放的少量流体在上升过程中可能交代地幔楔橄榄岩或与其发生反应:一方面,触发地幔楔橄榄岩发生熔融形成富Nb岛弧玄武质岩;另一方面,地幔组分迅速进入到板片熔体中,导致其地幔组分增加,乃至形成高镁安山岩。因此,天山北部地区石炭纪埃达克岩-高镁安山岩-富Nb玄武质岩组合表明:(1)天山北部地区石炭纪可能为岛弧环境而非裂谷环境;(2)天山地区石炭纪的地壳生长可能以侧向增生为主;(3)除了亏损地幔之外,俯冲洋壳的熔融可能也在地壳的生长中发挥了重要的作用;(4)俯冲板片产生的埃达克质岩浆具有高的氧逸度,而其与地幔楔橄榄岩的强烈相互作用将导致地幔中的金属硫化物分解,成矿金属元素进入到岩浆中。这可能是新疆北部铜金矿化与一些埃达克岩、高镁安山(闪长)岩或富Nb岛弧玄武质岩密切共生的基本原因。  相似文献   
78.
The Bikou volcanic terrane is predominated by subalkaline tholeiitic lavas. Rock samples display lower initial ratios of Sr and Nd, 0.701248-0.704413 and 0.511080-0.512341 respectively. 207Pb and 208Pb are significantly enriched in the lavas. Most samples have positive εNd, which indicates that the magma was derived from EM-type mantle source, while a few samples with negative εNd indicate that there was contamination in the magma evolution. Magma differentiation is demonstrated by variations of LREE and LILE from depletion to enrichment. Additionally, normalized REE patterns and trace elements showed that lavas from the Bikou volcanic terrane have similar characteristics to those of basalts in arc settings caused by subduction and collision. Analyses showed that the Bikou volcanic terrane is a volcanic arc. New evidence proved that the Hengdan Group, north of the Bikou arc, is a turbidite terrane filling a forearc basin. Consequently, the Bikou volcanic terrane and the Hengdan turbidite terrane const  相似文献   
79.
正The Neoarchaean to Palaeoproterozoic Transvaal Supergroup of the Kaapvaal Craton,southern Africa,is one of the best-preserved and most complete stratigraphic records across a critical in juncture in the Earth’s history.  相似文献   
80.
http://www.sciencedirect.com/science/article/pii/S167498711100079X   总被引:1,自引:0,他引:1  
Lower Paleozoic rocks exposed in various regions of Egypt (south central Sinai, north Eastern Desert and southwest Western Desert), in addition to occurring in the subsurface such as north Western Desert and the Gulf of Suez. The Lower Paleozoic rocks in Egypt include surface and subsurface rock units of formational status. The surface rock units are the Taba, Araba and Naqus formations. The subsurface rock units include the Shifa, Kohla and Basur formations. The Infracambrian Taba Formation has been discovered recently in the outcrops of the south eastern Sinai in the Taba-Ras El-Naqab area. It is missing and/or not recognized in the subsurface. The Taba Formation consists mainly of reddish brown, unfossiliferous gravelly fine-to medium-grained sandstones cemented by kaolinite and have subordinate beds of paleosols. The Cambrian Araba Formation and its subsurface equivalent (the Shifa Formation) are essentially composed of reddish brown, fine-grained laminated sandstone and siltstone with abundant Skolithos and Cruziana sp. In contrast, the Ordovician-Silurian Naqus Formation and its subsurface equivalents (Kohla Formation and Basur Formation) are mainly composed of white, unfossiliferous, cross-bedded, medium- to coarse-grained sandstones with haphazardly distributed pebbles and cobbles. Sedimentological analysis indicates that the Araba Formation and its equivalents were deposited in a marginal-marine environment, whereas the Naqus Formation and its equivalents were laid down in a fluvio-glacial environment. Integrated stratigraphic and sedimentological studies of the Lower Paleozoic rocks permit reconstruction of the paleogeography of Egypt at that time. Egypt has been largely controlled since the Cambrian by the pre-existing structural framework of the pre-Phanerozoic basement rocks inherited from the Late Proterozoic Pan-African event. Additionally, sedimentation processes were controlled during Cambro-Ordovician times by tectonic movements, whereas glacio-eustatic control predominated during the Late Ordovician-Silurian Period. These studies suggest that most areas of Egypt were exposed lands with episodically transgression by epicontinental seas related to the paleo-Tethys. These lands formed a part of a stable subsiding shelf at the northern Gondwana margin.  相似文献   
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