气象卫星低分辨率资料传输的数字化

气象卫星低分辨率模拟资料传输WEFAX即将数字化为LRIT，阐述了LRIT(低分辨率信息传输)内容、LRIT数据传输模式和系统结构以及各卫星运行国LRIT传输比较。     

钢筋混凝土结构电渗阻锈技术研究

通过测量电渗阻锈过程中阻锈剂渗入量、脱盐率以及钢筋极化电阻,研究了混凝土技术参数和电渗电量对电渗阻锈效果的影响.试验结果表明,电渗阻锈技术能在脱除盐污染混凝土中氯离子的同时,将有效阻锈基团快速迁移到钢筋表面,使已腐蚀的钢筋快速恢复钝化而达到防腐的目的.     

红外掩星观测的首批结果

自从1991年9月28日我们首次成功地进行了SAO076523的红外月掩星观测以来,又接连进行了一些成功的观测。本文将简要地介绍观测的设备、数据处理方法和初步的处理结果。     

青海盐湖锂资源开发现状及对提锂产业发展建议

中国正处在环境污染治理和产业结构调整的关键时期,发展新能源产业是应对能源和环境危机的必然选择;同时,锂资源储备和提锂技术直接影响到国家能源战略安全。中国科学院青海盐湖所经过二十年开发,目前已形成一套成熟的选择性离子迁移分离提锂技术,并经过了产业化和工业应用验证,核心技术达到国际领先水平。该产业化具有绿色、高效、低能耗、低物耗、低产品成本、高纯度等特点,技术通用性好,可推广应用到青海、西藏高海拔生态脆弱地区以及南美玻利维亚、阿根廷、智利等高镁锂比盐湖中锂的分离提取,在高钙镁地热水、油(气)田水提锂方面也有一定的应用潜力。     

Rare Earth Magnets: Conservation of Energy and the Environment

Rare earth sintered magnets (Nd magnet) have been used in many applications such as computer and industrial equipment, automobile manufacturing and many others. They are highly efficient and reduce energy consumption because of their superior magnetic properties. The element dysprosium (Dy) contained in the Nd magnet is important and indispensable. It improves the stability of the Nd magnet by enhancing the coercive force of its magnetic properties at high temperature. Dy is not so abundant. The rapid growth of the Nd magnet may result in Dy shortage. Exploration for new deposits of Dy is desired.     

负离子粉体材料的超细化和表面改性研究

采用聚羧酸盐为表面改性剂,用玛瑙球为研磨介质,研究电气石矿物粉末的研磨改性工艺,优化了最佳的研磨工艺条件,并对湿法研磨改性的电气石粉末进行了粒度分析测试.红外光谱显示,研磨改性后的电气石粉末表面带有聚羧酸基团,可进一步增进电气石粉末与各种材料的相容性能.改性后电气石粉未的负离子释放量达600个/cm3.     

Origin and Evolution of Silicic Magmatism at Yellowstone Based on Ion Microprobe Analysis of Isotopically Zoned Zircons

The origin of large-volume Yellowstone ignimbrites and smaller-volumeintra-caldera lavas requires shallow remelting of enormous volumesof variably ¹⁸O-depleted volcanic and sub-volcanic rocks alteredby hydrothermal activity. Zircons provide probes of these processesas they preserve older ages and inherited ¹⁸O values. This studypresents a high-resolution, oxygen isotope examination of volcanismat Yellowstone using ion microprobe analysis with an averageprecision of ± 0·2 and a 10 µm spot size.We report 357 analyses of cores and rims of zircons, and isotopeprofiles of 142 single zircons in 11 units that represent majorYellowstone ignimbrites, and post-caldera lavas. Many zirconsfrom these samples were previously dated in the same spots bysensitive high-resolution ion microprobe (SHRIMP), and all zirconswere analyzed for oxygen isotope ratios in bulk as a functionof grain size by laser fluorination. We additionally reportoxygen isotope analyses of quartz crystals in three units. Theresults of this work provide the following new observations.(1) Most zircons from post-caldera low-¹⁸O lavas are zoned,with higher ¹⁸O values and highly variable U–Pb ages inthe cores that suggest inheritance from pre-caldera rocks exposedon the surface. (2) Many of the higher-¹⁸O zircon cores in theselavas have U–Pb zircon crystallization ages that postdatecaldera formation, but pre-date the eruption age by 10–20kyr, and represent inheritance of unexposed post-caldera sub-volcanicunits that have ¹⁸O similar to the Lava Creek Tuff. (3) Youngand voluminous 0·25–0·1 Ma intra-calderalavas, which represent the latest volcanic activity at Yellowstone,contain zircons with both high-¹⁸O and low-¹⁸O cores surroundedby an intermediate-¹⁸O rim. This implies inheritance of a varietyof rocks from high-¹⁸O pre-caldera and low-¹⁸O post-calderaunits, followed by residence in a common intermediate-¹⁸O meltprior to eruption. (4) Major ignimbrites of Huckleberry Ridge,and to a lesser extent the Lava Creek and Mesa Falls Tuffs,contain zoned zircons with lower-¹⁸O zircon cores, suggestingthat melting and zircon inheritance from the low-¹⁸O hydrothermallyaltered carapace was an important process during formation ofthese large magma bodies prior to caldera collapse. (5) The¹⁸O zoning in the majority of zircon core–rim interfacesis step-like rather than smoothly inflected, suggesting thatprocesses of solution–reprecipitation were more importantthan intra-crystalline oxygen diffusion. Concave-downward zirconcrystal size distributions support dissolution of the smallercrystals and growth of rims on larger crystals. This study suggeststhat silicic magmatism at Yellowstone proceeded via rapid, shallow-levelremelting of earlier erupted and hydrothermally altered Yellowstonesource rocks and that pulses of basaltic magma provided theheat for melting. Each post-caldera Yellowstone lava representsan independent homogenized magma batch that was generated rapidlyby remelting of source rocks of various ages and ¹⁸O values.The commonly held model of a single, large-volume, super-solidus,mushy-state magma chamber that is periodically reactivated andproduces rhyolitic offspring is not supported by our data. Rather,the source rocks for the Yellowstone volcanism were cooled belowthe solidus, hydrothermally altered by heated meteoric watersthat caused low ¹⁸O values, and then remelted in distinct pocketsby intrusion of basic magmas. Each packet of new melt inheritedzircons that retained older age and ¹⁸O values. This interpretationmay have significance for interpreting seismic data for crustallow-velocity zones in which magma mush and solidified areasexperiencing hydrothermal circulation occur side by side. Newbasalt intrusions into this solidifying batholith are requiredto form the youngest volcanic rocks that erupted as independentrhyolitic magmas. We also suggest that the Lava Creek Tuff magmawas already an uneruptable mush by the time of the first post-calderaeruption after 0·1 Myr of the climactic caldera-formingeruption. KEY WORDS: Yellowstone; oxygen isotopes; geochronology; isotope zoning; zircon; U–Pb dating; caldera; rhyolite; ion microprobe     

288.15 K-323.15 K下氯化锂、硫酸锂溶液的密度及摩尔体积研究

用振荡管密度计测定了常压下,温度在288.15-323.15 K范围内不同离子强度的LiCl和 Li₂SO₄溶液的密度,计算了两种锂盐在不同温度下的表观摩尔体积,溶液的浓度范围分别为(0.1~18.9) mol·kg-1及(0.03~3.0)mol·kg-1。用Pitzer离子相互作用模型拟合了LiCl和Li₂SO₄不同温度下的的Pitzer单电解质体积参数,模型的计算值与实验值相吻合良好。     

NO_3~-对硼同位素测定的干扰及其消除

在石墨存在下测定Cs2BO2+离子是硼同位素测定的最佳方法，但NO3-却存在严重的干扰，本文对这种干扰进行了详细的研究。为了避免NO3-的干扰，本文改进了硼的分离提取方法，完全避免了NO3-的引入，取得了满意的测定结果。     

Rainwater acidity and ion concentration correlations in a midwest storm system

The pH and the concentrations of sulfate, nitrate, ammonia, and calcium in rainwater were measured for two periods of a single midwest rainstorm which occurred over a mesometeorological network in central Illinois on 24–25 July 1979. Regression analysis was used to compare ion concentrations with rainfall amount, and ion balance was used to compare cation and anion concentrations at individual sites. Only the ions SO₄ ^2- and NO₃ ^- show any significant relationship to rainfall amount, decreasing as rainwater amounts increase (r=–0.57 and –0.60, respectively). During the first period of the rainstorm, a sequential sampler measurements allowed the calculation of detailed temporal variations in SO₄ ^2-, pH, and rain rate. SO₄ ^2- decreased, and pH increased as the rate increased and the opposite temporal pattern occurred as the rain decreased at the end of the period. Reasons for these variations are discussed.Research done while a visiting scientist at the Illinois State Water Survey, Champaign, Illinois, U.S.A.