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101.
Concentrations of polycyclic aromatic hydrocarbons have been determined in sediments, mussels and crustacea in the vicinity of a former gasworks site by Shoreham Harbour, UK. Very high concentrations of PAH were found in the substrate, an ash-like material deposited on the former gasworks site, which exhibited a profile consistent with the major source of contamination being coal or coke tar produced during the period of gas production at the site. Elevated PAH concentrations were also found in mussels both from the beach below the former gasworks site, and from sites further to the east in Portslade and Hove. The significance of these concentrations were assessed using an approach which involved the calculation of benzo[a]pyrene equivalent conoentrations (BaPEs), summing concentrations of individual PAH on the basis of their comparative potency as carcinogens. BaPE ranged from values of, or close to, zero for crustacea, to 336 microg kg(-1) wet weight in mussels from Southwick Beach. The contaminated mussels are not exploited commercially but may be taken by casual gatherers, and notices have been posted to warn potential consumers. 相似文献
102.
福建沿海养殖贝类体石油烃总量水平的分布特征 总被引:9,自引:1,他引:8
对福建沿海6种主要养殖贝类体石油烃总量水平的分布特征进行了探讨.结果表明:福建沿海6种养殖贝类体石油烃总量水平范围在2.57 mg/kg.wet~61.5 mg/kg.wet之间,总平均10.5 mg/kg.wet其受测样品石油烃总量水平的频率分布,含量在5.00mg/kg~15.0mg/kg范围的样品占81.3%;其石油烃污染指数范围在0.2~4.0之间,总平均0.7,总体属轻度污染.福建沿海6种养殖贝类体石油烃总量水平的种间分布,缢蛏〉僧帽牡蛎〉翡翠贻贝〉太平洋牡蛎〉泥蚶〉菲律宾蛤子.其石油烃总量水平的空间分布,由闽南海区向闽中海区和闽东海区呈明显递减之势;其石油烃总量水平的时空分布,在2002-2004年间总体呈微弱上升之势,但缢蛏和僧帽牡蛎体石油烃含量的年际升幅比其它4种养殖贝类体的升幅大且较明显. 相似文献
103.
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105.
Determination of thermal maturity and organic matter type by principal components analysis of the distributions of polycyclic aromatic compounds 总被引:1,自引:0,他引:1
The thermal maturity and organofacies sensitivity of polycyclic aromatic compound (PAC) distributions was explored by examination of the aromatic fractions of solvent extracts from a diverse set of 53 shales, coals and kerogen macerals which have undergone either natural or artificial maturation and which represent all three principal sedimentary organic matter (OM) types. Systematic changes with maturation were observed in the following groups of isomers: tri- and tetramethylnaphthalenes, methyl- and dimethylphenanthrenes, methyl- and dimethyldibenzothiophenes, methylpyrenes, and methylchrysenes. The maturity differences were quantified by mathematical ratios of the relative concentrations of the more thermally stable isomers to the less stable, on the basis of theoretical considerations and empirical observations. The PAC maturity parameters, unlike those derived from saturated biomarker stereoisomers, are typically effective across the entire oil generation window. To compensate for the effects of OM type on the maturity parameters, they were combined using principal components analysis. The resulting first principal component was in good agreement with independent indicators of maturity. The relative distributions of C0–C3 alkylphenanthrenes, dibenzothiophene, methyldibenzothiophenes and methyldibenzofurans were evaluated by a separate principal components analysis. The results permitted an independent grouping of the samples by OM type and suggested additional, simple molecular ratios that allow graphical recognition of OM type, including the ratio of dibenzothiophenes to dibenzofurans and a ratio using C2-alkylphenanthrene isomers. 相似文献
106.
研究表明,现代松粉热模拟实验释放水的产出分两个阶段,两类水,第一阶段,400℃以前释放水为松粉内部以水分子形式存在的结合水,呈弱酸性(pH=6),为第一类水,第二阶段,400℃以上温度释放水为松粉内部和高岭石内部结构水(-OH),呈弱碱性(pH=9),为第二类水,现代松粉热模拟实验产出气体量随温度升主呈逐渐上升趋势,450℃以后上升梯度突然增大,所产气体分为两大类:I类为无机气体,由N2、H2和CO2气体组成,以CO2相对丰度最主为特征。CO2气主要来自有机酸的脱羧反应和离子太氧与有机质氧化还原反应产出CO2。H2气主要来自孢粉和烃,C4~C6异构饱和烃及丙烯、丁烯不饱和烃等分子物标志物,其中以甲烷相对丰度最高为特征,气态有机烃来自孢粉内有机物的热降解产物,松粉 拟实验中丰富的气态有机烃和无机气体的检测出,为研 相似文献
107.
高温气相色谱与石油分析 总被引:6,自引:0,他引:6
气相色谱最高柱温主要受柱系统技术水平的限制。使用耐高温如400℃以上的固定相,改善配套部件的某些性能,可以将传统气相色谱的柱温提高到325℃以上。高温气相色谱的应用将为高分子量烃类研究提供重要的分离鉴定手段。综合国内外研究动态论述了高温气相色谱在原油的模拟蒸馏、高蜡原油分析及石蜡产品表征等几方面的研究现状和发展方向。 相似文献
108.
A study was conducted to examine the OH-initiated degradation products of the four title compounds in the presence of sub-part-per-million levels of NOx. The oxidation was conducted in a dynamic reactor to minimize the conversion of the aromatic compounds. The experiments were designed to represent reaction pathways that occur in the atmosphere at ambient NO2 concentrations. A wide range of ring-retaining and ring-cleavage products having widely varying yields were measured during the study. For m-xylene, the major primary products observed (with molar yields) were methyl glyoxal (0.40), 4-oxo-2-pentenal (0.12), glyoxal (0.079), and m-tolualdehyde (0.049). For p-xylene, the major primary products were p-tolualdehyde (0.103), 2,5-dimethylphenol (0.13), cis-3-hexene-2,5-dione (0.176), trans-3-hexene-2,5-dione (0.045), 2-methyl-butenedial (0.071), glyoxal (0.394), and methylglyoxal (0.217). Several other reaction products were measured at yields less than 3%. The primary products for OH + 1,2,4-trimethylbenzene were found as follows: methylglyoxal (0.44), glyoxal (0.066), cis-3-hexene-2,5-dione (0.13), trans-3-hexene-2,5-dione (0.031), biacetyl (0.114), 3-methyl-3-hexene-2,5-dione (0.079), and 2-methyl-butenedial (0.045). Six other (ring retaining) products were measured at yields less than 3%. The primary products for OH + 1,3,5-trimethylbenzene were methylglyoxal (0.90), 3-methyl-5-methylidene-5(2H)-furanone (0.1), 3,5-dimethyl-3(2H)-2-furanone (0.1), 3,5-dimethyl-5(2H)-2-furanone biacetyl (0.08), and 2-methyl-4-oxo-2- pentenal (0.05). Three other products were detected at molar yields less than 5%. In some cases, the yields for the ring fragmentation products could only be based on calibrations from surrogate compounds. Yields for several of the unsaturated dicarbonyl compounds have not been reported previously while yields for methylglyoxal, glyoxal, and biacetyl are largely consistent with previous reports. Some of the primary furanone products are the identical to those reported as secondary products in aromatic systems. 相似文献
109.
有关煤成烃的基本认识 总被引:7,自引:0,他引:7
在煤化作用过程中,煤岩组分产出气相和液相物质的同时,固相煤岩组分本身也遭受改造。现今的固相煤岩组分与已产出的气相和液捐物质都是它们共有“前身”演化的“产物”,所以只根据固相煤岩组分的生烃潜能作为评价油气资源的依据还不够理想。煤在短时间高温条件下的热演化,与煤在漫长地质时期、低温条件下自然煤化作用过程中的热化有本质差异,用热解实验方法研究煤成烃尚存在一定问题。煤层内的气处在吸附一解吸和运移的动态平衡状态,决定煤层含气的主导因素是煤层的储气和运移条件,生烃潜能不起主导作用。 相似文献
110.