纤磷钙铝石类化合物:来自地球具工艺用途的材料(英文)     

Schw.  RG 《地学前缘》2000,7(2):485-497

纤磷钙铝石类化合物系由自纤磷钙铝石CaAl3 (OH) 6(HPO4) (PO4)本身、经磷钙铝石CaAl3 (OH) 6(SO4) (PO4)到钾明矾石KAl3 (OH ) 6(SO4) 2 等的天然矿物族所组成的。它们表现出具有很大范围的阳离子置换系列 ,其中以Sr2 +和Ba2 +置换Ca2 +,REEs3 +置换Ca2 +和H+,As5 +置换P5 +,S6+/Se6+置换H+P5 +最为重要。随着置换的进行 ,其热动力学稳定性也逐渐增加。由此 ,纤磷钙铝石类化合物成为很能抗风化的矿物 ,在红土中尤其如此。厚的纤磷钙铝石层形成在闪长岩 (富Sr) ,碳酸盐岩 (富REEs)和含金石英脉 (富As)之上 ,从而保护整个磷酸盐红土 ,使之免受风化。以此方式 ,形成了桌状山脉或岛屿 ,他们具有未受覆盖的表面。这些“纤磷钙铝”石化合物为上述及其它元素形成一有效的地球化学障。“纤磷钙铝石”的这种天然地球化学固定作用可以用适当的母体或人工合成晶体来进行模拟 ,即通过金属阳离子交换或就地反应来模拟。这种固定作用还可用于处理天然和人造的放射性裂变产物、有毒的重金属元素、砷酸盐和硒酸盐、硫酸盐等。  相似文献   

BOOK REVIEWS     

《The Professional geographer》1986,38(4):430-457

Book Reviewed in this article: Latin America: Case Studies . Richard G. Boehm and Sent Visser Locality and Rurality: Economy and Society in Rural Regions . Tony Bradley And Philip Lowe The City and the Grassroots . Manuel Castells Geopolitics and Conflict in South America. Quarrels among Neighbors . Jack Child Post-Industrial America: A Geographical Perspective . David Clark Coastal Research: UK Perspectives . Malcolm W. Clark A Rural Policy for the EEC? Hugh Clout Peasant Agriculture in Assam: A Structural Analysis . M. M. Das . Environmental Change and Tropical Geomorphology . I. Douglas and T. Spencer Advances in Abandoned Settlement Analysis: Application to Prehistoric Anthrosols in Colombia, South America . Robert C. Eidt Measuring Culture . Jonathan L. Gross and Steve Rayner North America: A Human Geography . Paul Guinness and Michael Bradshaw A Geographical Bibliography for American Libraries . Chauncy D. Harris et al. Geography and the Urban Environment: Progress in Research and Applications, Vol. VI . D. T. Herbert and R. J. Johnston Changes in Global Climate: A Study of the Effect of Radiation and Other Factors During the Present Century . K. Ya . Kondrat'ev . Rural Development and the State: Contradictions and Dilemmas in Developing Countries . David A. M. Lea and D. P. Chaudhri The Martial Metropolis: U.S. Cities in War and Peace . Roger W. Lotchin The Climate of the Earth . Paul E. Lydolph . Weather and Climate . Paul E. Lydolph . Spatial Divisions of Labor: Social Structures and the Geography of Production . Doreen Massey . Panorama of the Soviet Union . N. Mikhailov . Soviet Armenia . K. S. Demirchian . USSR: Geography of the Eleventh Five-Year Plan Period . K. Spidchenko . Planung und Verwirklichung der Wiener Ringstrassenzone (Planning and Materialization of the Ringstrasse-Zone of Vienna). Kurt Mollik , Hermann Reining , Rudolf Wurzer . The American West Transformed: The Impact of the Second World War Gerald D. Nash . An Overview of the Survey of Income and Program Participation . Dawn Nelson , David Mc Millen, and Daniel Kasprzyk . Phenomenology, Science and Geography: Spatiality and the Human Sciences . John Pickles . Biological Diversification in the Tropics . Ghillean T. Prance Die Wanderviehwirtschaft im gebirgigen Westen der U.S.A. und ihre Auswirkungen im Naturraum . Gisbert Rinschede . Social and Economic Aspects of Radioactive Waste Disposal: Considerations for Institutional Management . World-Wide Weather . K. Takahashi Coastal Geomorphology in Australia . B. G. Thom Settlement System in Rural India: A Case Study of the Lower Ganga-Yamuna Doab . Ram Chandra Tiwari . Computer Programming for Geographers . David J. Unwin and John A. Dawson . Late Quaternary Environments of the Soviet Union . A. A. Velichko, ed . H. E. Wright , Jr. and C. W. Barnosky Ethics in Planning . Martin Wachs  相似文献   

含苯并三唑废水处理方法探讨     

马生明  王守伟  钟佐燊  吴昆明  喻劲松 《地学前缘》2005,12(Z1):61-66

含苯并三唑废水是一类常规方法不能处理的化工废水,需要探讨有效的处理方法。在纳米科技理论指导下,以纳米微粒的吸附特性为切入点,确立了纳米微粒与无机高分子混凝剂最佳混凝形态之间联系的纽带。围绕混凝作用进行了纳米粉体材料混凝试验、无机高分子混凝剂混凝试验和电凝聚试验。结果发现,应用电凝聚法能有效去除废水中由苯并三唑产生的COD,从而成功地探索出有效处理含苯并三唑废水的方法。  相似文献   

Sorption of P by ferric hydroxide film, cover particles of sediments of Lake Baikal     

Alexander Likhoshvay Mikle Grachev 《中国地球化学学报》2006,25(B08):138-139

We investigated in more detail the adsorption phenomenon which was described earlier. It was clearly established that the hydroxyl apatite was not participated in P adsorption. This phenomenon takes place because of ferric hydroxide film. Modem sediments from the Southem Basin of Lake Baikal were taken and stirred with Baikal water. Carrier-free [^32p]-orthophosphate was added in this system. Similar experiments were made with carrier-free [^35S]-sulphate. Sulphate stayed in supematant completely. The influence of pH on the system with inorganic phosphate was also studied. In low alkali conditions phosphate migrated in supematant, in low acid, in sediments. Baikal sediment was stripped of iron-hydroxous film by treatment with 1% oxalic acid. Investigation of striped sediment shown that phosphate stays in supematant only. Hence, hydroxyl apatite cannot be the phase of the sediments of Lake Baikal which binds phosphate. This all showed by our group before. Now we have found the limit of phosphate sorption in Lake Baikal sediments and the stehiometry of the sorption. The sorption limit of Lake Baikal sediments was studied. An experiment with inorganic ^31P phosphate was made. 0.025% K2HPO4 solution with adding ^32P radioactive mark into it was prepared. 100 μL of mixture of ^31PO4^3- and ^32PO4^3- seven times were added in a ＂Baikal water-Baikal sediment＂ system and blank （100 ml BW only）. Concentrations of inorganic ^31PO4^3- were very low so the bend dot on the diagram was found and sorption limit of sediment was estimated. Baikal sediment stopped assimilating phosphate in the bend dot. The stehiometry of sorption was estimated by supematant-sediment radioactive ratio, which equals 3, that is, three Fe （Ⅲ） atoms associate one PO4^3- anion. The only Fe （Ⅲ） substance which could associate P is -Fe-O-Fe- polymer film. It also dissolves in acid conditions.  相似文献   

离子色谱法测定高纯镁砂中痕量无机阴离子     

伯英侯倩慧  余季金 《岩矿测试》2006,25(3):288-290

采用阴离子交换色谱电导检测法分析高纯镁砂（MgO）中的无机阴离子。MgO粉末在管式电炉1250-1350℃高温下通氧气加热，硫酸盐和氯化物等受热分解，气态生成物被40mL含25mg镁粉的0．25mol／LNaOH溶液吸收。方法的回收率为93．7％-95．3％，精密度（RSD，n=5）为4．32％-4．63％。对若干相关的分析技术问题，亦进行了讨论。  相似文献   

The effect of gross primary production, net primary production and net ecosystem exchange on the carbon fixation by chemical weathering of basalt in northeastern Iceland     

Marin Ivanov Kardjilov  Sigurdur Reynir Gíslason  Gudrún Gísladttir 《Journal of Geochemical Exploration》2006,88(1-3):292

The overall objective of this study is to define and interpret the annual dissolved inorganic carbon (DIC) flux in selected river catchments in North Eastern Iceland. The flux stems primarily from chemical weathering of basalt. The DIC flux out of the catchments is compared with the spatial distribution of the various vegetation communities and their gross primary production (GPP), net primary production (NPP) and net ecosystem exchange (NEE). There is no correlation between the DIC flux and the GPP, but one between DIC and NPP. The DIC flux is highly dependent on the NEE, which in turn is governed by the area extent of wetlands in these catchments. A variation by a factor 5 of the NEE results in a variation by a factor 2.8 in the river dissolved inorganic flux.  相似文献   

Reduction of Ammonia and Hydrogen Sulfide Emission from Swine Manure Using Aqueous Foams Amended with Microorganisms and Chemical Additives     

Seung‐Ryong Lee  Joon Kyoung Han  Yong Ju Choi  Kyoungphile Nam 《洁净——土壤、空气、水》2007,35(3):230-234

Aqueous foam, in combination with microorganisms and chemical additives, was tested for the reduction of the emissions of odorous compounds from swine manure. Ammonia and hydrogen sulfide were selected as test compounds. Aqueous foam decreased the ammonia and hydrogen sulfide emissions by about 33.2 and 66.2%, respectively, after application for 1,800 min. With the application of aqueous foam, amended with 1% of monocalcium phosphate or Yucca extracts, about 81.4 and 51.6%, respectively, of the ammonia emissions were suppressed over the same time period. However, the chemical additives were found to be ineffective in the suppression of hydrogen sulfide. Finally, the aqueous foam, containing microorganisms and the two chemical additives, attained about 88.3 and 70% ammonia and hydrogen sulfide emissions suppression, respectively. The data show that the aqueous foam was effective in the control ammonia and hydrogen sulfide emissions, and the suppression capacity can be markedly enhanced by the addition of appropriate microorganisms and chemical additives.  相似文献   

广西海湾红树林区表层海水无机氮含量的时空变化及富营养化评价     

何本茂  韦蔓新  范航清  潘良浩  曹庆先 《台湾海峡》2014,(1):140-148

利用2007年12月至2008年11月间对广西海湾红树林区进行4个季节调查的资料,研究了溶解无机氮的时空变化、组成特征及其与富营养化的关系．结果表明,研究海区溶解无机氮含量较高,年平均质量浓度达0．53mg／dm3,NO3-N含量占66．93％,是N的主要存在形态;廉州湾红树林区质量浓度最高,为1．15mg／dm3;其次为钦州湾,为0．41mg／dm3;铁山港和珍珠湾红树林区较低,均为0．25mg／dm3;陆源输入是影响DIN含量变化的主导控制因素,生物作用次之,化学作用影响较小．相关分析显示：各种形态无机氮（NO3-N、NO2-N、NH4-N）之间的相似性主要出现于径流影响较小的海区和季节,径流影响较大的海区和季节相似性较差,与N的来源途径广而复杂有关;海区水体已呈明显富营养化,但随海区和季节不同变化极大,径流影响最大的廉州湾红树林区富营养化指数（E）高达24．84,已达高富营养化水平,其余海区均在1．52～1．74之间;DIN是该海区富营养化形成的重要影响因子,DIP次之,COD的影响较小;这是红树林区具有较强水体自净能力的重要体现．  相似文献   

Comparison on soil carbon stocks between urban and suburban topsoil in Beijing,China   总被引：1，自引：0，他引：1  

Shanghua Luo  Qizheng Mao  Keming Ma 《中国地理科学(英文版)》2014,24(5):551-561

The urban population and urbanized land in China have both increased markedly since the 1980s. Urban and suburban developments have grown at unprecedented rates with unknown consequences for ecosystem functions. In particular, the effect of rapid urbanization on the storage of soil carbon has not been studied extensively. In this study, we compared the soil carbon stocks of different land use types in Beijing Municipality. We collected 490 top-soil samples （top 20 cm） from urban and suburban sites within the Sixth Ring Road of Beijing, which cover approximately 2400 km2, and the densities of soil organic carbon （SOC）, soil inorganic carbon （SIC）, and total carbon （TC） were analyzed to determine the spatial distribution of urban and suburban soil carbon characteristics across seven land use types. The results revealed significant differences in soil carbon densities among land use types. Additionally, urban soil had significantly higher SOC and SIC densities than suburban soil did, and suburban shelterbelts and productive plantations had lower SIC densities than the other land use types. The comparison of coefficients of variance （CVs） showed that carbon content of urban topsoil had a lower variability than that of suburban topsoil. Further findings revealed that soil carbon storage increased with built-up age. Ur- ban soil built up for more than 20 years had higher densities of SOC, SIC and TC than both urban soil with less than 10 years and sub- urban soil. Correlation analyses indicated the existence of a significantly negative correlation between the SOC, SIC, and TC densities of urban soil and the distance to the urban core, and the distance variable alone explained 23.3% of the variation of SIC density and 13.8% of the variation of TC density. These results indicate that SOC and SIC accumulate in the urban topsoil under green space as a result of the conversion of agricultural land to urban land due to the urbanization in Beijing.  相似文献   

酸化过程对海洋沉积物中有机碳同位素分析的影响   总被引：6，自引：1，他引：5  

彭亚君  王玉珏  刘东艳  唐丹玲 《海洋学报》2015,37(12):85-92

海洋沉积物中有机碳同位素(δ13C)可以示踪海洋生态系统中有机质来源,对环境研究具有重要意义。分析沉积物中有机物的δ13C,需要对样品进行酸化,以去除无机碳的影响。由于不同来源的沉积物中无机碳的含量和组份存在差异,需要针对样品性质,优化酸化处理过程。本研究分别选取了无机碳含量不同的温带与热带河口、海湾沉积物样品,比较了3种不同酸化过程对有机物δ13C分析的影响。研究结果表明:方法1(酸洗法)中6%H_2SO_3和1mol/L H_3PO_4对无机碳含量较高的热带河口、海湾样品去除效率较低,而2mol/L HCl去除无机碳酸盐的效果较理想。方法2(酸蒸法)并不适用于无机碳含量较高的热带河口、海湾样品;而对于无机碳含量相对较低的温带河口、海湾样品,9h酸蒸较为适宜。方法3(非原位酸洗)的结果较方法1和方法2偏正,表明其对含13C丰富的有机组分破坏较小,且方法3中残留的酸对δ13C的分析没有影响。因此,方法3是去除海洋沉积物中无机碳较理想的方法。  相似文献