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591.
合成了3种单核配合物,通过元素分析、摩尔电导和红外光谱进行了表征。在动态空气下,采用热重和差热技术研究了N,N′-双氨烷基草酰胺合铜(Ⅱ)配合物热分解动力学。用Achar法和Coats-Redfen法分析了非等温动力学数据,并对比动力学参数提出了最合适的热分解动力学模型。由热重曲线计算出了热分解反应的活化能、热焓和指前因子。对比配合物N,N′-双-2氨乙基草酰胺合铜(Ⅱ)、N,N′-双-2氨丙基草酰胺合铜(Ⅱ)和N,N′-双-3-氨丙基草酰胺合铜(Ⅱ)初始分解温度,配合物的热稳定性排序为:Cu(oxpn)>Cu(oxap)>Cu(oxen) 相似文献
592.
塔里木盆地原油高压条件下裂解成气的化学动力学模型及其意义 总被引:9,自引:1,他引:9
针对塔里木盆地油藏保存深度明显大于其它沉积盆地的实际情况,本文设计进行了可以模拟塔里木盆地高压条件的油裂解成气实验.不同压力条件下的实验产物特征和产率表明,压力的确对油裂解成气过程有明显影响.由带压条件下的实验数据所建立和标定的化学动力学模型显示,轻质油较正常油成气的活化能高.与由非高压条件下油裂解成气实验所得化学动力学参数相比,高压条件下油裂解成气的加权平均活化能明显偏高.从而定量证明了高压对油裂解成气进程的抑制作用及含杂原子较少的轻质油更难裂解成气的实质。 相似文献
593.
XIONG Yongqiang GENG Ansong WANG Yunpeng LIU Dehan JIA Rongfen SHEN Jiagui XIAO Xianming 《中国科学D辑(英文版)》2002,45(1):13-20
The kinetic parameters of generation have been obtained for different hydrocarbon classes, including methane, C2-C5 gas hydrocarbons, C6-C13 light hydrocarbons and C13+ heavy hydrocarbons, and vitrinite reflectance (R°) by the kinetic simulating experiment of kerogen cracking. Then, combined with the detailed geology of Sichuan Basin, the
effective gas-generating intensity of the Lower Cambrian source rock is approximately estimated by applying these parameters. 相似文献
594.
The I-atom sensitised decomposition of ozone in air at 1 atm pressure and ambient temperature has been investigated. Iodine atoms were produced by photolysis of I2 using visible light or of CH3I using ultraviolet light. In both cases, the quantum yield for O3 decomposition was 1.25 (±0.11) per I atom. An important role is proposed for the self-reaction of IO radicals leading to higher oxides of iodine, IO+IO(+M)I2O2(+M)higher oxides, which predominated over the bimolecular reaction leading to regeneration of I atoms, IO+IO2I+O2, with k
2a/k
2b4. Simple computer modelling calculations indicate that reaction (2a) may be important in determining the fate of photolabile iodine species in the atmosphere. The consequences for the behaviour of radioiodine releases are also discussed. 相似文献
595.
Abstract: Transportation of various kinds of elements occurred in wall rocks (Quaternary andesites) during the hydrothermal alteration accompanied by the Hishikari epithermal gold mineralization. For example, K2 O and MgO contents of wall rocks decrease away from the gold-quartz veins, while (CaO+Na2 O) content increases, and SiO2 content is variable near the veins. Hydrothermal alteration zoning and bulk compositional variations in wall rocks suggest that the mixing of hydrothermal solution and acidic groundwater took place an important role as the cause for the hydrothermal alteration and bulk compositional variations. The relationship between dissolved silica concentration and temperature of hydrothermal solution mixed with groundwater is obtained based on precipitation kinetics-fluid flow–mixing model, and the computed results are compared with the distribution of SiO2 minerals (quartz and cristobalite) in the hydrothermal alteration zones. This comparison suggests that the most reasonable flow rate of fluids migrating through hydrothermal alteration zones, and A/M (A: surface area of rocks interacting with fluid, M: mass of fluid) are estimated to be ca. 10-4.2 m/sec, and ca. 0.10 m2 /kg, respectively. The mixing of two fluids (hydrothermal solution and acidic groundwater) can also explain δ18 O zoning in the altered country rocks, hydrothermal alteration zoning from K-feldspar through K-mica to kaolinite from the center (veins) to margin, and deposition of gold. 相似文献
596.
煤岩初次和二次生烃动力学及其对沾化凹陷孤北天然气成因的解释 总被引:5,自引:1,他引:4
沾化凹陷孤北地区石炭一二叠系(C-P)潜山产出煤成气,油气勘探需要搞清楚产出的煤成气是煤岩初次埋藏、还是抬升剥蚀后再次埋藏生成的.在查明该区煤岩地质演化的基础上,采用热模拟实验方法,探讨了煤岩初次和二次生烃过程中气态烃与主要单体烃生成动力学特征,发现煤岩二次生烃的活化能比一次生烃高40~50 kJ/mol,认为孤北地区C-P煤系源岩达到4200 m深度条件(R°约0.9%)才发生二次生烃作用.与煤岩初次生气相比,二次生气具有iC4/nC4<1、n(C6 C7)/i(C6 C7)>0.8、甲苯/苯<1.2等特征,据此认为孤北煤成气是煤岩二次生烃形成的. 相似文献
597.
开放体系下有机质与有机碳、氢、氮损失动力学研究 总被引:2,自引:0,他引:2
本文对Ⅰ、Ⅱ、Ⅲ型干酪根的有机质、有机碳、氢、氮的损失进行了动力学研究,获得了Ⅰ、Ⅱ、Ⅲ型干酪根的总量、有机碳、氢以及氮质量损失动力学参数。此动力学参数可用于烃源灶的有机质总量,有机碳、氢、氮质量的恢复研究。在此基础上,结合专用Kinetics 软件,将此动力学参数应用于干酪根有机碳丰度、氢/碳和氮/碳原子比恢复系数计算。结果表明,在Ro介于0.47%~3.05%之间Ⅰ型干酪根有机碳丰度,碳、氢、氮总丰度,氢/碳和氮/碳原子比的恢复系数依次为1~1.89、1~1.96、1~2.13和1~0.56;Ⅱ型干酪根依次为0.98~1.05、1~1.06、1~1.89和1~0.66。Ⅲ型干酪根依次为1~0.82、1~0.83、1~1.59和1~0.56。因此在对高成熟—过成熟干酪根进行生烃评价时,Ⅰ、Ⅲ型干酪根残余有机碳丰度需要进行恢复,而Ⅱ型干酪根残余有机碳丰度不需要进行恢复。3种类型干酪根的H/C原子比均需要进行恢复。本文建立的Ⅰ、Ⅱ、Ⅲ型干酪根恢复动力学可用于计算开放体系热演化过程中残留干酪根或有机碳总量,在一定程度上弥补了以往着重考虑生出烃类演化的不足之处。 相似文献
598.
Xiangcan Jin Shengrui Wang Haichao Zhao Xiaoning Zhou Fengchang Wu 《Environmental Geology》2008,56(2):391-398
The effect of organic matter on the sorption of dissolved organic matter (DOM) on lake sediments is critical to understanding
the fate and transport of contaminants at the sediment–water interface in lake ecosystems. Results indicate that DOM sorption
on sediment is largely due to ligand exchange between the DOM and hydroxyl groups, and the amount of DOC sorbed is a linear
function of added DOC. With increasing organic matter content the sediment has lower binding strength, higher releasing ability
for DOM, and the higher amount of DOM sorbed by sediment naturally. There was no clear difference before and after the sediment
was treated with H2O2, but the constant b implied that after the sediments were treated DOC release was promoted. Organic matter in the sediment tends to impede the
sorption of DOC and results in a remarkable decrease in DOC sorption rates. 相似文献
599.
Victor W. Truesdale 《Aquatic Geochemistry》2008,14(4):359-379
The cubic equation recently derived for the increase in concentration of a solute with time, as the solid dissolves in batch
according to the shrinking sphere model at high under-saturation, is extended to dissolutions of mixtures of differently sized
particles. This problem needs to be solved if batch dissolutions are to play their part in the proposed amelioration of global
warming and associated climate change by accelerated ‘re-burial’ of excess CO2 in ocean sediment. The upgraded model was tested using sodium chloride dissolved in 50% aqueous propanone, whence the model
fitted two separate runs with 500 and 212 μm, and 212 and 38 μm, diameter crystals, respectively. The key to simulating dissolution
in this way lies in the dissolutions being independent of each other. It is further shown that although this condition was
implicit in the recent derivation of the cubic equation, it was not recognised at the time. The work should be applicable
to any batch dissolution of mixed particles at high under-saturation, and hence, may find use in many industrial and laboratory
dissolutions. Simulations show how agglomerated mixtures can yield a straight line on the plot of ln(1 − C/C
T) versus time, as was reported to occur recently with sodium chloride taken ‘straight from the bottle’. It is shown that this
probably explains why exponential dissolutions may have seemed appropriate to the dissolution of biogenic silica in earlier
literature. This study suggests that a new round of biogenic silica dissolutions, but with sieved samples, would be worthwhile,
with the likelihood that shrinking sphere behaviour might well be found to characterise the kinetics. The opportunity is taken
to investigate a number of aspects of the shrinking sphere model not generally discussed before, e.g. the graph for the change
in surface area with time. The limitations of using cubic salt crystals with the shrinking sphere model are discussed. 相似文献
600.