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分别以Y沸石、活性碳和二氧化硅-壳聚糖(SiO2-CS)为载体、利用浸渍法制备了一系列负载型七水三氯化铈-碘化钠(CeCl3·7H2O-NaI)催化剂,考察了它们在叔丁基苯基醚的脱保护反应中的催化性能。 结果表明,SiO2-CS为载体的催化剂呈现出良好的催化性能和较高的稳定性。 另外,在中性条件下,SiO2-CS负载CeCl3·7H2O-NaI催化剂在叔丁基醚及1,3-二硫缩醛脱保护反应中呈现出较高的催化活性,从而避免使用强酸和强碱。 相似文献
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采用水热法制备了一种新型稀土配位聚合物[Dy(3-PA)3(H2O)]n(3-PA=3-吡啶丙烯酸)(1),并通过X射线单晶衍射结构分析、元素分析、红外光谱、热重分析对配合物1进行了结构表征.结构分析表明,标题配合物属于三斜晶系,Pī空间群,晶胞参数为:a=0.617 16(5)nm,b=1.270 45(11)nm,c=1.564 03(13)nm,α=111.557 0(10)°,β=90.307 0(10)°,γ=95.342 0(10)°,V=1.134 54(16)nm3,Z=2.金属离子Dy(III)通过配体3-AP羧基的桥联作用,链接成为一维双螺旋链状配位聚合物. 相似文献
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A novel turn-on rhodamine B-based fluorescent chemosensor (RBCS) was designed and synthesized by reacting N-(rhodamine B)lactam-1,2-ethylenediamine and carbon disulfide. Upon addition of Fe3+ in EtOH/H2O solution (2:1, v/v, HEPES buffer, 0.6?mM, pH 7.20), the RBCS displayed a significant fluorescence enhancement at 582?nm and a dramatic color change from colorless to pink, which can be detected by the naked eye. Significantly, the RBCS exhibited a highly selective and sensitive ability toward Fe3+. The detection limit of the probe was 2.05?×?10?7?M. Job's plot indicated the formation of 1:1 complex between the RBCS and Fe3+. Moreover, the practical use of the RBCS is demonstrated by its application in the detection of Fe3+ in HeLa cells. 相似文献
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Xing Li Zhi-Qin Sun Hong-Hong Chang Wen-Long Wei 《中国化学快报》2014,25(8):1174-1178
FeX3(X = Cl, Br) were found to be very effective reagents and powerful catalysts for regioselective ring openings of a variety of N-tosylaziridines with them to afford the corresponding b-haloamines in good to excellent yields with high regioselectivity under mild conditions. At the same time, 13 new compounds were obtained firstly. Moreover, the b-bromoamine prepared could be transferred into b-nitroamine with NaNO2 in moderate yield. 相似文献
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利用电喷雾质谱(ESI-MS)和紫外-可见吸收光谱(UV-Vis)分析,研究了CrCl3·6H2O 浓度为0.1~0.6 mol·L-1的水溶液和[1ChCl∶2EG]/CrCl3·6H2O ILs中,Cr(Ⅲ)配合物的存在形式。研究结果表明,在含有CrCl3·6H2O的溶液中,Cr(Ⅲ)与Cl-和H2O形成[Cr(H2O)nCl6-n]n-3配合物,其配合物的优势物种受CrCl3·6H2O浓度的影响。水溶液中Cr(Ⅲ) 的优势配合物为[Cr(H2O)6]3+与[Cr(H2O)5Cl]2+,并随CrCl3·6H2O浓度增加,水溶液的UV-Vis吸收光谱峰红移,[Cr(H2O)5Cl]2+的相对含量增加。而[1ChCl∶2EG]/CrCl3·6H2O ILs中的优势配合物为[Cr(H2O)2Cl4]-和[Cr(H2O)3Cl3],且随CrCl3·6H2O 浓度增加,溶液的颜色从浅橙红色逐渐变为深绿色,溶液的UV-Vis吸收光谱峰蓝移,[Cr(H2O)3Cl3]的相对量增加。说明CrCl3·6H2O的浓度变化,将影响配体Cl-和H2O与Cr(Ⅲ)配位结合的配位数,从而影响配合物优势物种的相对量。 相似文献
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The effects of pH,contact time and natural organic ligands on radionuclide Eu(Ⅲ) adsorption and mechanism on titanate nanotubes(TNTs) are studied by a combination of batch and extended X-ray absorption fine structure(EXAFS) techniques.Macroscopic measurements show that the adsorption is ionic strength dependent at pH < 6.0,but ionic strength independent at pH > 6.0.The presence of humic acid(HA) /fulvic acid(FA) increases Eu(Ⅲ) adsorption on TNTs at low pH,but reduces Eu(Ⅲ) adsorption at high pH.The results of EXAFS analysis indicate that Eu(Ⅲ) adsorption on TNTs is dominated by outer-sphere surface complexation at pH < 6.0,whereas by inner-sphere surface complexation at pH > 6.0.At pH < 6.0,Eu(Ⅲ) consists of ~ 9 O atoms at REu?O ≈ 2.40 in the first coordination sphere,and a decrease in NEu-O with increasing pH indicates the introduction of more asymmetry in the first sphere of adsorbed Eu(Ⅲ).At long contact time or high pH values,the Eu(Ⅲ) consists of ~2 Eu at REu-Eu ≈ 3.60 and ~ 1 Ti at REu-Ti ≈ 4.40 ,indicating the formation of inner-sphere surface complexation,surface precipitation or surface polymers.Surface adsorbed HA/FA on TNTs modifies the species of adsorbed Eu(Ⅲ) as well as the local atomic structures of adsorbed Eu(Ⅲ) on HA/FA-TNT hybrids.Adsorbed Eu(Ⅲ) on HA/FA-TNT hybrids forms both ligand-bridging ternary surface complexes(Eu-HA/FA-TNTs) as well as surface complexes in which Eu(Ⅲ) remains directly bound to TNT surface hydroxyl groups(i.e.,binary Eu-TNTs or Eu-bridging ternary surface complexes(HA/FA-Eu-TNTs)).The findings in this work are important to describe Eu(Ⅲ) interaction with nanomaterials at molecular level and will help to improve the understanding of Eu(Ⅲ) physicochemical behavior in the natural environment. 相似文献
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