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31.
氯代甲苯双电荷离子的单分子解离反应研究 总被引:1,自引:0,他引:1
研究了在70 eV电子轰击电离条件下,氯代甲苯及氯化苄产生的双电荷离子[C_7H_7Cl]~(2+)、[C_7H_6Cl]~(2+·)和[C_7H_5Cl]~(2+)为母体的两种类型单分子解离反应.主要讨论了亚稳双电荷离子的异构化反应、失H解高的“偶电子规则”以及单分子电荷分离过渡态的结构. 相似文献
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新型尿素吸附剂研究—褐藻酸Cu(Ⅱ)络合物吸附脲分子研究 总被引:1,自引:0,他引:1
首次利用褐藻酸Cu(Ⅱ)络合物配位吸附尿素分子,系统研究了影响尿素吸附的各种因素,并用红外光谱,紫外可见光谱分析手段对尿素吸附机制作了初步探讨,结果表明,褐藻酸Cu(Ⅱ)络合物在模拟人体生理介质下可络合吸附近60mg/g的吸附容量,其中尿素吸附液浓度为130.0mg/dl,介质为磷酸氢二钠和磷酸二氢钠的缓冲液(pH=7.0),温度为37℃。 相似文献
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36.
大孔树脂孔结构的表征 总被引:2,自引:0,他引:2
本文论述了大孔离子交按树脂和吸附树脂孔结构的测试方法,并阐述了各种测试方法所存在的问题。 相似文献
37.
使用2,6-二苯基-4-(2,4,6-三苯基-1-吡啶鎓)苯氧内盐染料(Reichardt's Dye)研究锂离子电池中非水电解质溶剂碳酸酯的极性,并测量极性经验参数ET(30)碳酸乙烯酯为48.6,碳酸丙烯酯为46.1,2,3-碳酸丁烯酯为45.7,碳酸二甲酯为39.0,碳酸甲乙酯为37.3,碳酸二乙酯为37.0.LiClO4加入到碳酸酯溶剂中,显色剂受到离子的盐效应影响,表现为溶液体系的ET(30)值增加,极性增大.由于溶液中粒子间的相互作用不同,环碳酸酯与链状碳酸酯极性变化趋势不同.极性大的溶剂易形成Ar-O-…solvent…Li+结构,起到缓冲作用,抑制了显色剂的酚氧基与Li+直接作用. 相似文献
38.
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
39.
某些离解能、电子亲合能等的G2计算与评价 总被引:1,自引:1,他引:1
PoPle及其合作者创立的Gaussian再简称GZ)理论[‘-’],以其相对可靠的化学精度和相应较小的计算量已经引起了实验和理论化学家们的广泛关注问.p。ple等人在他们的GZ文章中强调了GZ的理论计算结果在研究离解能等化学问题中与精确实验数据之间的偏差普遍不大于全8.狄J规厂‘.我们近期的研究表明*’1,*2和优(*则在计算一般化学反应能量中,绝大多数情况下,分别都能保证结果与实验偏差在全8.4和士13kJ·mol‘以内.近年来,已有大量的研究工作表明,GZ的理论结果已广泛用于未知实验数据的预测、已有实验数据的评价和修正等… 相似文献
40.
Solvation interaction and ion association in solutions of lithium perchlorate/4-methoxymethyl-ethylene carbonate (MEC) have been studied by using Infrared and Raman spectra as a function of concentration of lithium perchlorate. The splitting of ring deformation band and ring ether asymmetric stretching band, and the change of carbonyl stretching band suggest that there should be a strong interaction between Li^+ and the solvent molecules, and the site of solvation should be the oxygen atom of carbonyl group. The apparent solvation number of Li^+ was calculated by using band fitting technique. The solvation number was decreased from 3.3 to 1.1 with increasing the concentration of LiClO4/MEC solutions. On the other hand, the band fitting for the ClO4^- band revealed the presence of contact ion pair, and free ClO4^- anion in the concentrated solutions. 相似文献