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61.
本文介绍了在Windows环境下,用可视Basic研制的G-856质子磁力仪实测数据预处理程序。该程序具有读入数据、日变改正、梯度改正、高度改正、磁参数计算、误差计算、图形的显示与编辑、打印各种数据与图形的功能。最后,结合野外工作实例讨论了其优点。  相似文献   
62.
The celestial pole coordinates   总被引:2,自引:0,他引:2  
The coordinates of the Celestial Ephemeris Pole in the Celestial Reference System (CRS) can advantageously replace the classical precession and nutation parameters in the matrix transformation of vector components from the CRS to the Terrestrial Reference System (TRS). This paper shows that the new matrix transformation using these coordinates in place of the preceding parameters would be conceptually more simple, especially when associated with the use of the non-rotating origin on the instantaneous equator (Guinot 1979, Capitaine et al. 1986) and of a celestial reference frame as realized by positions of extragalactic sources. In such a representation, the artificial separation between precession and nutation is avoided and the practical computation of the matrix transformation only requires the knowledge of the two celestial direction cosines of the pole, instead of the large number of the quantities generally considered. The development of these coordinates is given as function of time so that their use is equivalent (when using the CRS defined by the mean pole and mean equinox of epoch J2000.0, the 1976 IAU System of Astronomical Constants and the 1980 IAU theory of nutation) to the one of the conventional series for the precession (Lieske et al. 1977) and nutation (Seidelmann 1982) parameters. Such a theoretical development should also be used in order to derive more directly the numerical coefficients of the celestial motion of the instantaneous equator from very precise observations such as VLBI.
Résumé Les coordonnées du Pôle Céleste des Ephémerides dans le Systeme de Référence Céleste (CRS) pourraient remplacer avantageusement les paramètres classiques de precession et de nutation dans la matrice de transformation entre le CRS et le Système de Référence Terrestre (TRS). Cet article montre que la nouvelle matrice de transformation utilisant ces coordonnées à la place des paramètres classiques serait ainsi conceptuellement plus simple, en particulier lorsque l'on utilise l'origine non-tournante sur l'équa-teur instantané (Guinot 1979, Capitaine et al. 1986), ainsi que le repère de référence céleste réalisé par les positions des radiosources extragalactiques. Une telle representation évite la séparation artificielle entre précession et nutation et le calcul de la matrice de transformation correspondante ne nécessite que la connaissance des deux cosinus directeurs du pole dans le repère céleste, au lieu du grand nombre de paramètres considérés généralement. Le dèveloppement de ces coordonnées en fonction du temps est donné de façon à ce que leur usage soit équivalent (lorsque l'on se rapporte au CRS défine par le pôle et l'équinoxe moyens de l'époque J2000.0, au Système de Constantes Astronomiques IAU-1976, ainsi qu'au modèle UAI-1980 de la nutation) à celui des séries conventionnelles de la precession (Lieske et al. 1977) et de la nutation (Seidelmann 1982). Un tel développement théorique devrait également être utilise pour déterminer plus directement les coefficients numériques du déplacement céleste de l'équateur instantané, à partir des observations très précises, comme par exemple, les observations VLBI.
  相似文献   
63.
回顾了1900年以来LAU采用天文常数系统的简况,以及一些天文常数之间的数学关系,并描述了以前每次改变天文常数系统的主要因为.介绍了1991年以来IAU在天文常数方面的工作:包括IAU天文常数工作组和天文常数最佳估计值的情况.叙述了IAU 2009年天文常数系统替代IAU 1976天文常数系统的因为:随着人类对太阳系的探测,获得新的天文常数测定值;1991年以来在相对论框架下BCRS和GCRS的使用;P03岁差模型和MHB2000章动模型的采用.比较了IAU2009和1976天文常数系统的差异.最后介绍中国在天文常数方面工作的情况和今后工作的建议.  相似文献   
64.
张体强  胡树国  韩桥 《岩矿测试》2014,33(6):775-781
超高纯气体在工业生产中有非常重要的地位,如半导体工业中电子气的质量直接影响半导体器件的性能,百万分之几的微量杂质气体便可导致集成电路中元件存储信息量的减少。越来越高的气体纯度要求对分析方法及仪器的灵敏度提出了很大的挑战。大气压电离质谱(APIMS)由于可以在大气压条件下对杂质进行电离,并伴随高效的电离方式,因此具有极高的灵敏度,成为超高纯气体杂质分析中极为有效的技术手段,特别适合检测10-9 mol/mol甚至10-12 mol/mol浓度量级的气体杂质。APIMS采用电晕放电及63Ni两种电离源,通常以电晕放电电离源为主,质量分析器常采用四极杆,同时为适应超高纯气体分析,APIMS配备了气体进样系统及可将标准气体稀释产生校正气体的稀释系统。APIMS对杂质检测的灵敏度与杂质的电离方式密切相关,电荷传递是杂质电离最主要的一种方式,适用于电离能相差较大的底气与杂质,常见的N2、Ar由于电离能较高,其中的大部分杂质均可依靠该方式测定;质子转移反应的应用通常与H2有关,常用于H2中杂质的测定,也可以通过添加H2的方法促进对Ar中N2杂质的检测;运用形成团簇离子的反应尽管较少,但亦有报道,通过监测团簇离子O2+·H2O,可提高O2中杂质H2O的检测灵敏度。依据不同的电离反应,可以设计对不同杂质的测定方式,实现对痕量、超痕量杂质的检测。APIMS检测灵敏度通常比电子轰击电离质谱(EI/MS)高104~106倍,因此目前依然是超高纯气体分析中不可替代的仪器方法,但在某些方面如对有腐蚀性电子特气的分析,方法灵敏度有待提高。  相似文献   
65.
The experiments of the dissolution kinetics of fluorite were performed in aqueous HCl solutions over the temperature range of 25–100 °C using a flow-through experimental apparatus. With a constant input of aqueous HCl solution through the reactor, output concentrations of the dissolved species Ca, F, Cl vary with flow rate, as well as with the surface compositions. Measured output concentrations of dissolved species and the pH can be used to determine a rate law for fluorite dissolution. Fluorite dissolution rates are found to be pH dependent. Usually, dissolution rates of fluorite decreases with increasing dissolved Ca in the output solution at 25 and 100 °C. Dissolution rate can be expressed as
(1a)
where k is the rate constant and α is the order with respect to the hydrogen ion activity vs. the activity of dissolved Ca. The α was obtained from kinetic experiments. For the fluorite sample passed through 18–35 mesh, α =1.198 at 100 °C and k = 10−0.983, while fluorite dissolved in HCl–H2O solution at pH 2.57 of input solution. Adsorption of a proton and Cl−1onto the fluorite surface, surface cation exchange and the formation of the surface complex Ca(F, Cl)2 and/or (H2x, Ca1−x)(F, Cl)2 control dissolution rates. Investigation of the fluorite surface before and after dissolution by using X-ray photoelectron spectroscopy (XPS) indicate that surface modifications affect reaction rates.  相似文献   
66.
The new theory of Self Creation Cosmology has been shown to yield a concordant cosmological solution that does not require inflation, exotic non-baryonic Dark matter or unknown Dark Energy to fit observational constraints. In vacuo there is a conformal equivalence between this theory and canonical General Relativity and as a consequence an experimental degeneracy exists as the two theories predict identical results in the standard tests. However, there are three definitive experiments that are able to resolve this degeneracy and distinguish between the two theories. Here these standard tests and definitive experiments are described. One of the definitive predictions, that of the geodetic precession of a gyroscope, has just been measured on the Gravity Probe B satellite, which is at the present time of writing in the data processing stage. This is the first opportunity to falsify Self Creation Cosmology. The theory predicts a ‘frame-dragging’ result equal to GR but a geodetic precession of only 2/3 the GR value. When applied to the Gravity Probe B satellite, Self Creation Cosmology predicts an E–W gravitomagnetic/frame-dragging precession, equal to that of GR, of 40.9 milliarcsec/yr but a N–S gyroscope (geodetic + Thomas) precession of just 4.4096 arcsec/yr.  相似文献   
67.
There are two ways of expressing the precession of orbital plane of a binary pulsar system, given by Barker & O'Connell, Apostolatos et al. and Kidder, respectively. We point out that these two ways actually come from the same Lagrangian under different degrees of freedom. Damour & Schafer and Wex & Kopeikin applied Barker & O'Connell's orbital precession velocity in pulsar timing measurement. This paper applies Apostolatos et al.'s and Kidder's orbital precession velocity. We show that Damour & Schafer's treatment corresponds to negligible Spin-Orbit induced precession of periastron, while Wex & Kopeikin and this paper both found significant (but not equivalent) effects. The observational data of two typical binary pulsars, PSR J2051-0827 and PSR J1713+0747, apparently support a significant Spin-Orbit coupling effect. Specific binary pulsars with orbital plane nearly edge on could discriminate between Wex & Kopeikin and this paper: if the orbital period derivative of the double-pulsar system PSRs J0737-3039 A and B, with orbital inclination angle i = 87.7129 deg, is much larger than that of the gravitational radiation induced one, then the expression in this paper is supported, otherwise Wex & Kopeikin's is supported.  相似文献   
68.
1 IntroductionTheAuroralStationinAdventdalenwasbuiltin 1 978andhasworkedasanopticalsiteforground -basedobservationsofthedaysideandnightsideaurorainthepolarcap .Figure 1showsaphotographofthestationtogetherwithatypicalstormtypeaurora(Simmonsetal.1 996) .Thestatio…  相似文献   
69.
国际天文联合会(IAU)2006决议1推荐采用P03岁差模型代替IAU2000A岁差模型,该模型的岁差参数由用户选择。针对这一决议,绘制了表示岁差章动参数之间关系的天极图和分点图,讨论了与目前决议相一致的坐标转换规律,并对岁差章动参数的各种选择方案及其特点进行了详细研究。这不仅为新决议中P03岁差模型的推广应用提供了有力的支持,同时也进一步明确了各种岁差章动参数之间的关系及其在实用中应注意的问题。  相似文献   
70.
This study examined the UV/H2O2 decolorization efficiency under high UV photon flux (intensity normalized by photon energy) irradiation; the incident UV was ranging from 3.13 × 10?8 to 3.13 × 10?6 einstein cm?2 s?1. The experimental results showed that complete decolorization of 20 mg L?1 methylene blue (MB) can be achieved within 5 s and 99% decolorization of 1000 mg L?1 MB can be achieved in 180 s under the best condition of high UV intensity UV/H2O2 process. To the best of our knowledge, UV/H2O2 decolorization process in such a short time has not been reported. The electrical energy per order of the process was 16.21 kWh m?3 order?1 and it is relatively economical compared with other advanced oxidation processes. The kinetics of decolorization follows pseudo‐first order. There is a linear relationship between rate constant and UV intensity, which indicates that increasing UV intensity does not cause decline in light utilization efficiency. The experiment related to initial substrate concentration shows decolorization rate of different substrate concentration (20–1000 mg L?1) are closed to each other. Besides, optimal H2O2 concentration, comparative study with low photon flux light, decolorization of other types of dyes and TOC removal were also studied.  相似文献   
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