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Using acetonitrile or DMF as cosolvent, both perfluoroalkyl iodides such as Cl(CF2)nI (n = 4,6,8, la—lc ), CF3 (CF2)n I (n = 5,6,7, ld—lf ), I (CF2)n O (CF2) SO3 Na(n = 2,4,6, lg—li ) and perfluoroalkyl bromides such as Cl (CF2)n Br (n = 4,6, 3a—3b ) and C7F15 Br (3e) reacted with Rongalite in aqueous solution to give the corresponding sulfinates Cl (CF2)n SO2 Na (n = 4,6,8, 2a—2c ), CF3-(CF2)nSO2Na (n = 5,6,7, 2d—2f ) and NaO2S(CF2)nO(CF2)2SO3Na (n = 2,4,6, 2g—2i ) in moderate yields. 1 H-perfluoroalkanes were formed as the main products when other solvents such as ethanol. iso-propanol, 1,4-dioxane and morpholine were used. 相似文献
83.
Yu-Jun Zhu Zhong-Liang Lei Da-Kang Huang Bo Lian Zhen-Jiang Liu Xiao-Jun Hu Jin-Tao Liu 《Tetrahedron letters》2018,59(33):3184-3187
A novel decarboxylative difluoromethylation reaction of PhSO2CF2COOK with aldehydes under metal- and ligand-free conditions has been developed. The reaction is very mild and tolerates a wide range of aldehydes (both enolizable and non-enolizable aldehydes), providing a facile and efficient method for the synthesis of structurally diverse difluoromethylated carbinols in moderate to excellent yields. 相似文献
84.
Lin-Dong Liu Zhong-Liang Lei Hong Wang Ming Bian Zhen-Jiang Liu Jin-Tao Liu Xiao-Jun Hu 《Tetrahedron》2018,74(34):4515-4520
A metal-free inorganic base-mediated highly stereoselective hydroamination of arylalkynes with imidazoles has been developed, and the corresponding N-vinylimidazoles were obtained in good yields and with moderate to excellent stereoselectivities (up to 99:1). For the electron rich alkynes, the reaction system of CsOH·H2O/NMP/140?°C led to the predominant formation of E-addition products, while the reaction system of KOH/NMP/90?°C afforded the Z-isomers as the major product. The electron deficient alkynes furnished predominantly the E-addition products in both reaction systems. This study essentially provides a general and an efficient protocol for the synthesis of E-isomer of the N-vinylimidazoles. 相似文献
85.
ZHANG Jin-Tao NIE Jin SUN Si-Xun JI Guo-Zhen JIANG Xi-KuiShanghai Institute of Organic Chemistry Chinese Academy of Sciences Fenglin Lu Shanghai China 《中国化学》1994,12(2):179-182
The effect of temperature on the critical aggregate concentration (CAgC) has been investigated for the first time, by measurement of the hydrolytic rate constants of p-nitrophenyl dodecanoate (C12) and hexadecanoate (C16) at different temperatures in the 30:70 V/V (Φ=0.30) and 40:60 V/V (Φ= 0.40) dioxane (DX)-H2O systems. The CAgC values of C12 and C16 increase with the increase of the temperature, i.e., high temperatures disfavor aggregation. Activation energies for the hydrolysis of C12 in the monomeric and aggregated concentration domains have also been discussed. 相似文献
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本文采用实验测量和数值模拟结合的方法,对AC放电下He/CH4/O2混合气中激发态对甲烷裂解和低温氧化的动力学贡献进行研究。基于HP-Mech,增加反应物的放电机理以及激发态参与的化学反应及其驰豫反应,建立CH4低温氧化机理。采用化学反应动力学求解器CHEMKIN中的两段式Plasma-PSR模型模拟放电过程及化学反应过程。该动力学模型能较好地预测反应物的消耗和主要产物的生成,反应路径分析表明激发态物质CH4(v),O2(v),O2(a^1△g)等通过链式反应CH4(v)+OH→CH3+H2O,O2(v)+H→OH+O,O2(a^1△g)+H→OH+O促进活性自由基和产物的生成。 相似文献