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在星载方位多通道SAR斜视模式下,方位斜视角度和运动目标的速度分别导致回波多普勒频谱发生2次混叠和通道失衡,影响运动目标方位多通道信号重建.针对该问题,该文提出一种适用于多通道斜视模式下的运动目标的重建方法.首先通过方位向去斜预处理消除了斜视导致的2次多普勒混叠,然后通过修正的多通道重建矩阵来解决目标速度导致的通道失衡.此外,该文还研究了通道冗余情况下的杂波抑制能力,分析了估计速度误差带来的残余相位误差,给出了一种星载方位多通道SAR斜视模式下的运动目标速度快速估计搜索方法.最后,通过点目标仿真验证了方法的有效性. 相似文献
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传统频谱扩展与压缩(SSC)盲移频干扰的阶数为整数,为了实现精确的位置干扰,需要调整不同的处理延时,在实际应用中存在一定的局限性.该文对整数阶盲移频技术进行了改进,提出了一种基于非整数阶SSC盲移频的LFM雷达干扰技术.该技术在干扰机处理延时不变的情况下,通过改变SSC盲移频的阶数来实现精确的位置干扰.该文推导了一种高效的非整数阶SSC盲移频干扰实现方法,同时通过Newman序列控制信号的初相来减小压制干扰信号的峰均比(PAPR).仿真结果表明,该文算法在指定干扰机处理延时的情况下,可以实现假目标欺骗干扰和相参密集压制干扰,能够有效对抗脉冲压缩体制雷达,具有较好的工程应用价值. 相似文献
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工业生产維生素甲中,乙酰化是采用乙炔鋰作試剂。其标准制备法是通乙炔入鋰的液体氨溶液。如果不慎溅出,氨蒸发后卽发生火光。假如使乙炔鋰与乙 相似文献
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A general method in considering the core electronic correlation energies has been proposed and introduced into the standard Gaussian-2 (G2)[7] theory by small post-Hartree-Fock calculations. In this paper an additional MP2(FC)/6-31G(d) calculation over the G2 procedures is employed and examined in modification in modification to the flaw of Frozen-Core (FC) approximation of G2 vai eq.:
ΔE(full)= E[MP2(full)/6-31G(d)]-E[MP2(FC)/6-31G(d)]
where the MP2(full)/6-31G(d) energy has been obtained in the molecular geometry optimizations. This energy, ΔE(full), is directly added into the total G2 energy of a molecule in facilitating the effect of core electronic correlations for each molecule in chemical reactions. It has been shown that the over-all average absolute deviation for the 125 reaction energies of the G2 test set (test set 1) is slightly reduced from 5.09 to 5.01 kJ, mol(-1) while for the 55 D0 values, which have been used for the derivation of the A coefficient of the empirical High-Level...更多-Correction (HLC), it is also reduced from 4.99 [for both G2 and G2(COMPLETE)[8]]to 4.77 kJ• mol(-1). In addition, larger errors (greater than ±8.4 kJ•mol(-1) for the D0 energies are improved, especially for the largest error of the D0 of SO2 This error is reduced from 21.3 to 15.4 kJ. mol(-1), in which the experimental geometry would further reduce it by 7.1kJ.mol(-1)[8]. Another improvement is the absolute value of the A coefficient in HLC being reduced from 4.81 for G2 to 4.34 milli-hartrees which is believed to be useful in isolating the relationship between the HLC and the FC approximation. Modifications to the original G2 from this work is denoted as G2(fu 1) and thus the G2 (fu 1) total energy for a molecule is
E[G2(fu 1)]= E[G2]+Δ E(full)h
with a new ΔE[HLC] =-0.19α- 4.34nβ milli-hartree. 相似文献
ΔE(full)= E[MP2(full)/6-31G(d)]-E[MP2(FC)/6-31G(d)]
where the MP2(full)/6-31G(d) energy has been obtained in the molecular geometry optimizations. This energy, ΔE(full), is directly added into the total G2 energy of a molecule in facilitating the effect of core electronic correlations for each molecule in chemical reactions. It has been shown that the over-all average absolute deviation for the 125 reaction energies of the G2 test set (test set 1) is slightly reduced from 5.09 to 5.01 kJ, mol(-1) while for the 55 D0 values, which have been used for the derivation of the A coefficient of the empirical High-Level...更多-Correction (HLC), it is also reduced from 4.99 [for both G2 and G2(COMPLETE)[8]]to 4.77 kJ• mol(-1). In addition, larger errors (greater than ±8.4 kJ•mol(-1) for the D0 energies are improved, especially for the largest error of the D0 of SO2 This error is reduced from 21.3 to 15.4 kJ. mol(-1), in which the experimental geometry would further reduce it by 7.1kJ.mol(-1)[8]. Another improvement is the absolute value of the A coefficient in HLC being reduced from 4.81 for G2 to 4.34 milli-hartrees which is believed to be useful in isolating the relationship between the HLC and the FC approximation. Modifications to the original G2 from this work is denoted as G2(fu 1) and thus the G2 (fu 1) total energy for a molecule is
E[G2(fu 1)]= E[G2]+Δ E(full)h
with a new ΔE[HLC] =-0.19α- 4.34nβ milli-hartree. 相似文献