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61.
中条山分布着大片的碳酸盐岩层。年降水量740mm, 年平均气温14℃。气候条件和多次的构造运动, 控制和决定了中条山喀斯特的发育程度、地貌景观, 以及岩溶地下水的赋存和运移特征。在水利水电建设中, 渗漏成了非常突出的工程地质问题, 对坝址选择产生了一定的影响。  相似文献   
62.
蔡曙光  李军  李冰 《盐湖研究》2001,9(4):41-47
在大约1mol·dm-3的盐酸水溶液中测定了K2O·MgO·6B2O3·10H2O的溶解焓。结合已获得的其它热化学数据,得出K2O·MgO·6B2O3·10H2O的标准摩尔生成焓为-(12250.35±9.68)kJ·mol-1,并利用“基团贡献法”计算出标准摩尔吉布斯自由能为-11103kJ·mol-1。从而计算出其标准摩尔生成熵和标准摩尔熵。  相似文献   
63.
Kojitani  H.  Nishimura  K.  Kubo  A.  Sakashita  M.  Aoki  K.  Akaogi  M. 《Physics and Chemistry of Minerals》2003,30(7):409-415
Raman spectroscopy of calcium ferrite type MgAl2O4 and CaAl2O4 and heat capacity measurement of CaAl2O4 calcium ferrite were performed. The heat-capacity of CaAl2O4 calcium ferrite measured by a differential scanning calorimeter (DSC) was represented as CP(T)=190.6–1.116 × 107T–2 + 1.491 × 109T–3 above 250 K (T in K). The obtained Raman spectra were applied to lattice dynamics calculation of heat capacity using the Kieffer model. The calculated heat capacity for CaAl2O4 calcium ferrite showed good agreement with that by the DSC measurement. A Kieffer model calculation for MgAl2O4 calcium ferrite similar to that for CaAl2O4 calcium ferrite was made to estimate the heat capacity of the former. The heat capacity of MgAl2O4 calcium ferrite was represented as CP(T)=223.4–1352T –0.5 – 4.181 × 106T –2 + 4.300 × 108T –3 above 250 K. The calculation also gave approximated vibrational entropies at 298 K of calcium ferrite type MgAl2O4 and CaAl2O4 as 97.6 and 114.9 J mol–1 K–1, respectively.  相似文献   
64.
盐类溶解动力学的数学模型和热力学函数   总被引:5,自引:0,他引:5       下载免费PDF全文
总结了研究盐类溶解动力学的方法和数学模型。采用C语言编写了自动寻优的单线形法,实现了含4个参数的通用程序,并例举了研究实例。另外讨论了热力学函数的处理,也例举了研究实例。  相似文献   
65.
Wadeite K2ZrSi3O9 and its analogues K2TiSi3O9 and Cs2ZrSi3O9, synthesized by high-temperature solid-state sintering, have been investigated using powder X-ray diffraction coupled with Rietveld analysis and high-temperature oxide melt solution calorimetry. The crystal chemistry and energetics of these phases, together with K2SiVISi3 IVO9, a high-pressure wadeite analogue containing both tetrahedral and octahedral Si, are discussed in term of ionic substitutions. As the size of the octahedral framework cation increases, Si4+ → Ti4+ → Zr4+, the cell parameter c increases at a much higher rate than a. In contrast, increasing the interstitial alkali cation size (K+ → Cs+) results in a higher rate of increase in a compared with c. This behavior can be attributed to framework distortion around the interstitial cation. The enthalpies of formation from the constituent oxides (ΔHf,ox0) and from the elements (ΔHf,el0) have been determined from drop-solution calorimetry into 2PbO·B2O3 solvent at 975 K. The obtained values (in kJ/mol) are as follows: ΔHf,ox0 (K2TiSi3O9) = −355.8 ± 3.0, ΔHf,el0 (K2TiSi3O9) = −4395.1 ± 4.8, ΔHf,ox0 (K2ZrSi3O9) = −374.3 ± 3.3, ΔHf,el0 (K2ZrSi3O9) = −4569.9 ± 5.0, ΔHf,ox0 (Cs2ZrSi3O9) = −396.6 ± 4.4, and ΔHf,el0 (Cs2ZrSi3O9) = −4575.0 ± 5.5. The enthalpies of formation for K2SiVISi3 IVO9 were calculated from its drop-solution enthalpy of an earlier study (Akaogi et al. 2004), and the obtained ΔHf,ox0 (K2SiSi3O9) = −319.7 ± 3.4 and ΔHf,el0 (K2SiSi3O9) = −4288.7 ± 5.1 kJ/mol. With increasing the size of the octahedral framework cation or of the interstitial alkali cation, the formation enthalpies become more exothermic. This trend is consistent with the general behavior of increasing energetic stability with decreasing ionic potential (z/r) seen in many oxide and silicate systems. Further, increasing the size of the octahedral framework cation appears to induce more rapid increase in stability than increasing the interstitial alkali cation size, suggesting that framework cations play a more dominant role in wadeite stability.  相似文献   
66.
在HCl-NiSO4-H2 O混合溶液中 ,以标准氢电极和银—氯化银电极组成无液接电池 ,恒定溶液总离子强度I和NiSO4在溶液中的离子强度分数yB 的条件下 ,在 2 78 1 5~ 3 2 3 1 5K温度范围内测定下列电池的电动势Pt,H2 ( 1 0 1 3 2 5kPa) |HCl(mA) ,NiSO4(mB) ,H2 O|AgCl-Ag由于体系存在硫酸的二级解离 ,应用数学迭代方法确定平衡体系氢离子的浓度 ,计算了混合溶液中HCl的活度系数γA,结果表明 ,在溶液总离子强度保持恒定时 ,HCl的活度系数服从Harned规则。在溶液组成恒定时 ,盐酸的活度系数logγA 对热力学温度l/T作图 ,是一条直线  相似文献   
67.
本文从目前我国铀矿地质面临的形势和国内外铀矿地质发展的实际情况出发论述了寻找经济可采用可溶浸的铀矿床是我国铀矿地质工作目前的必然选择。铀矿地质工作必须以经济效益为中心,近期的主攻方向是寻找经济可溶浸的铀矿床,尤其是寻找可地浸砂岩型铀矿床。文中还提出了确保铀矿地质找矿目标顺利实际的几项措施。  相似文献   
68.
电解质水溶液的结构   总被引:1,自引:0,他引:1       下载免费PDF全文
房春晖 《盐湖研究》1995,3(2):59-73
本文叙述了盐湖中主要离子Li+、Na+、K+、Mg2+、Ca2+、Cl-、SO_4 ̄2-、NO_3和纯水的结构,介绍了主要研究方法X射线衍射.分析了溶液结构研究历史和现状,对溶液结构研究的未来进行了展望.  相似文献   
69.
房春晖  房艳 《盐湖研究》1995,3(4):66-71
本文介绍了X射线衍射法测定液体结构的一些实验技术,包括光源波长和稳定性、单色X射线的获得、测量条件的选择、实验数据的校正等。  相似文献   
70.
CO2 concentrations at depths of 15,30, and 50 cm were determined over a one-year period in six karst soils in the Malay peninsula. Evidence suggests that the highest single CO2 value (MAXCO2, per cent) recorded at each site/depth provides the best estimate of conditions during groundwater recharge events. Soil depth (cm) and bulk density (BDEN) are the best predictors of MAXCO2, with the equation loglo(MAXCO2) = 1·146 (BDEN) + 0·00698 (DEPTH) - 1·227 accounting for 86 per cent of the variation. This equation is used to model MAXCO2 at seven, more remote sites. Soil throughflow patterns and groundwater recharge points are estimated from slope pantometer and soil depth surveys in order to assess the CO2 concentration with which soil waters ultimately equilibrate before entering the limestone. Limestone weathering seems to be predominantly of the open system type, the overall mean MAXCO2 of 1·65 per cent corresponding with a weathering potential of 167 ppm CaCO3. Weathering potentials vary markedly, ranging from 62–82 ppm on rocky hilltops to more than 280 ppm on certain tower karst footslopes in Selangor and the Kinta Valley and on moderate hillslopes developed in impure limestones in the Boundary Range.  相似文献   
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