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121.
新型两性氨基树脂复鞣剂的合成研究 总被引:5,自引:2,他引:3
以一氯乙酸、苯胺、尿素、双氰胺、三聚氰胺和甲醛为原料合成了适用于皮革复鞣的新型两性氨基树脂复鞣剂。进行了一系列优化实验,确定了最佳合成条件。通过红外光谱测定,证实了产品结构中某些基团的存在。 相似文献
122.
气相法合成N,N-二乙基苯胺 总被引:1,自引:0,他引:1
采用乙醚作烷基化试剂 ,在氧化铝催化剂上对气相法N ,N -二乙基苯胺的合成进行了研究。考察了反应温度、原料配比和空速等因素对反应的影响 ,确定了最佳工艺条件 :温度 3 10℃、空速 1 0h- 1 ,n(乙醚 ) /n(苯胺 ) =1 5。在此基础上 ,进行了 180 0h的稳定性试验和 10 0ml催化剂单管放大试验。结果表明 ,该催化剂稳定性良好 ,且小试与放大试验结果基本一致。 相似文献
123.
Copolymer nanofibrils composed of pyrrole and aniline had been prepared by synthesizing the desired polymer within the pores of microporous anodic aluminum oxide (AAO) template membrane. To analyze their structure and properties, FTIR spectra were taken and thermogravimetric analysis (TGA) was applied. Also, the copolymer nanofibrils were photographed under scanning electron microscopy (SEM) and transmission electron microscopy (TEM) for microstructure analysis, and the conductivities were obtained by the four‐probe method. The result of SEM and TEM revealed that the obtained copolymer nanofibrils had uniform and well‐aligned array, and their diameter and length can be controlled by changing the aspect ratios of the AAO membrane. The result of IR spectrometry and TGA indicated that both polypyrrole and polyaniline were involved in the copolymer. The obtained nanofibrils were identified to be copolymer rather than composite. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3002–3007, 2001 相似文献
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在自行研制的具有恒温加热进样系统的激光质谱仪上获得了260~285nm波段气相苯胺分子的共振增强多光子电离/飞行时间质谱(REMPI-TOFMS)。结合在266nm激发波长下得到的C6H7N^+、C5H6+、C4H3^+、C3H3^+、C2H4^+及H2CN^+离子的光强指数及不同激光能量下备离子信号强度的分支比,对分子离子及主要碎片离子的生成机理进行了探讨:在此波段范围内,苯胺分子首先吸收一个光子跃迁至。B2第一激发态,处于激发态的苯胺分子再吸收一个光子电离生成分子离子C6H7N+,分子离子进一步吸收光子解离为C5H6^+、H2CN^+、C6H^+,碎片离子C6H5^+继续吸收光子解离产生C4H3^+、C3H3^+、C2H4^+,并给出了可能的解离通道。 相似文献
127.
以苯胺废水处理站剩余污泥为菌源,经富集、扩大培养获得高含量的硝化菌菌液,并以自行研制的纤维颗粒为载体进行了挂膜试验,考察了pH、溶解氧(DO)和无机碳源等主要工艺条件对苯胺降解硝化过程的影响。结果显示,在15d内微生物开始在载体表面形成生物膜,30d后膜厚稳定在120~150μm。条件试验结果表明,pH为8.5时硝化效果最佳,氨氧化速率达到43.22mg/L·d;DO为3.0mg/L时满足苯胺降解菌及硝化菌代谢需要;添加无机碳源可有效促进硝化反应的进行,当NaHCO3添加量为300mg/L,可使硝化速率提高30.68%。由此证明了在三相生物流化床中通过条件优化可消除苯胺废水降解过程释放的富余氨氮。 相似文献
128.
Viktria Hajdu Gbor Murnszky Mikls Nagy Erika Kopcsik Ferenc Kristly Bla Fiser Bla Viskolcz Lszl Vanyorek 《International journal of molecular sciences》2022,23(12)
Aniline (AN) is one of the most important compounds in the chemical industry and is prepared by the catalytic hydrogenation of nitrobenzene (NB). The development of novel, multifunctional catalysts which are easily recoverable from the reaction mixture is, therefore, of paramount importance. Compared to conventional filtration, magnetic separation is favored because it is cheaper and more facile. For satisfying these requirements, we developed manganese ferrite (MnFe2O4)–supported, magnetically separable palladium catalysts with high catalytic activity in the hydrogenation of nitrobenzene to aniline. In addition to high NB conversion and AN yield, remarkable aniline selectivity (above 96 n/n%) was achieved. Surprisingly, the magnetic support alone also shows moderate catalytic activity even without noble metals, and thus, up to 94 n/n% nitrobenzene conversion, along with 47 n/n% aniline yield, are attainable. After adding palladium nanoparticles to the support, the combined catalytic activity of the two nanomaterials yielded a fast, efficient, and highly selective catalyst. During the test of the Pd/MnFe2O4 catalyst in NB hydrogenation, no by-products were detected, and consequently, above 96 n/n% aniline yield and 96 n/n% selectivity were achieved. The activity of the Pd/MnFe2O4 catalyst was not particularly sensitive to the hydrogenation temperature, and reuse tests indicate its applicability in at least four cycles without regeneration. The remarkable catalytic activity and other favorable properties can make our catalyst potentially applicable to both NB hydrogenation and other similar or slightly different reactions. 相似文献
129.
dm Prekob kos Szamosvlgyi Gbor Murnszky Jnos Lakatos Zoltn Knya Bla Fiser Bla Viskolcz Lszl Vanyorek 《International journal of molecular sciences》2022,23(12)
Carbon foam was synthesized by the carbonization of 4-nitroaniline. The reaction is an alternative of the well-known “carbon snake” (or sugar snake) demonstration experiment, which leads to the formation of nitrogen-doped carbon foils due to its nitrogen content. The synthesized carbon foils were grinded to achieve an efficient catalyst support. Palladium nanoparticles were deposited onto the surface of the support, which showed continuous distribution. The prepared Pd nanoparticle decorated carbon foils showed high catalytic activity in nitrobenzene hydrogenation. By applying the designed catalyst, total nitrobenzene conversion, a 99.1 n/n% aniline yield, and an exceptionally high selectivity (99.8 n/n%) were reached. Furthermore, the catalyst remained active during the reuse tests (four cycles) even without regeneration. 相似文献
130.