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991.
A new type of modified bismaleimide resin was obtained by copolymerization between tris(allylphenoxy)triazine monomer (TAPT) and an aromatic diamine‐chain‐extension bismaleimide [e.g., 4,4′‐diaminodiphenylmethane (DADPM)‐chain‐extension 4,4′‐bismaleimidodiphenylmethane (BMDPM)]. The new three‐component‐polymer system had good processibility and mechanical properties. Better results were obtained when the weight ratio of TAPT to the DADPM‐chain‐extension BMDPM resin was 30%. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 475–480, 2004 相似文献
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994.
Yulian Jiang Jianchang Liu Shubin Tan Pingsong Ming 《International journal of systems science》2014,45(9):1869-1879
In this paper, a robust consensus algorithm is developed and sufficient conditions for convergence to consensus are proposed for a multi-agent system (MAS) with exogenous disturbances subject to partial information. By utilizing H∞ robust control, differential game theory and a design-based approach, the consensus problem of the MAS with exogenous bounded interference is resolved and the disturbances are restrained, simultaneously. Attention is focused on designing an H∞ robust controller (the robust consensus algorithm) based on minimisation of our proposed rational and individual cost functions according to goals of the MAS. Furthermore, sufficient conditions for convergence of the robust consensus algorithm are given. An example is employed to demonstrate that our results are effective and more capable to restrain exogenous disturbances than the existing literature. 相似文献
995.
离子交换法处理含Cr(Ⅵ)废水的研究 总被引:4,自引:2,他引:4
采用201×7强碱性阴离子交换树脂处理模拟含Cr(Ⅵ)废水,探讨了废水酸度、交换时间、浓度对Cr(Ⅵ)去除率的影响以及树脂再生所需的合适温度和再生剂浓度。结果表明,201×7强碱性阴离子交换树脂处理模拟含Cr(Ⅵ)废水,具有交换容量大、交换效果好、树脂再生条件较简单等优点。并对实际含铬废水进行了处理,废水中Cr(Ⅵ)的初始浓度为1 540 mg/L,处理量达52 BV(床体积)时,出水中Cr(Ⅵ)的浓度仍小于0.5 mg/L,达到国家排放标准。树脂交换容量约80 mg/g。用8%NaOH溶液,在50℃条件下进行再生效果较好,再生率大于95%,可实现树脂的重复使用。 相似文献
997.
Pristine and functionalized multiwalled carbon nanotubes (MWNTs) were used to fabricate polyamide 6 (PA6) composites through melt blending. The functionalized MWNTs were obtained by grafting 1,6‐hexamethylenediamine (HMD) onto the pristine MWNTs to improve their compatibility with PA6 matrix. The effect of MWNTs on the isothermal crystallization and melting behavior of PA6 was investigated by differential scanning calorimetry (DSC) and X‐ray diffraction (XRD). The Avrami and Lauritzen–Hoffmann equations are used to describe the isothermal crystallization kinetics. The values of the Avrami exponent found for neat PA6, the pristine MWNTs/PA6 and functionalized MWNTs/PA6 composite samples are about 4.0, 1.7, and 2.3, respectively. The activation energies are determined by the Arrhenius method, which is lower for the composites, ?320.52 KJ/mol for pristine MWNTs/PA6 and ?293.83 KJ/mol for functionalized MWNTs/PA6, than that for the neat PA6 (?284.71 KJ/mol). The following melting behavior reveals that all the isothermally crystallized samples exhibit triple melting endotherms at lower crystallization temperature and double melting endotherms at higher crystallization temperature. The multiple melting endotherms are mainly caused by the recrystallization of PA6 during heating. The resulting equilibrium melting temperature is lower for the composites than for neat PA6. In addition, polarizing microscopy (PLM) and small angle light scanning (SALS) were used to study the spherulite morphology. The results show that the MWNTs reduce the spherulite radius of PA6. This reduction is more significant for pristine MWNTs. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
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999.
Two chemically modified starch derivatives, crosslinked amino starch (CAS) and dithiocarbamates modified starch (DTCS), were prepared and used for the removal of Cu(II) from aqueous solutions. CAS was found to be effective for the adsorption of Cu(II), which tended to form a stable amine complex. Adsorption of Cu(II) onto DTCS was higher than that onto CAS. Experiments showed that the adsorption processes of Cu(II) on both CAS and DTCS were endothermic, and followed Freundlich isothermal adsorption. For both adsorbents, dynamic modeling of their adsorption showed that the first‐order reversible kinetic model described the adsorption process. The adsorption rate constants of CAS and DTCS were 1.578 and 10.32 h?1, respectively. From the results of the thermodynamic analysis, free energy ΔG, enthalpy ΔH, and entropy ΔS of the adsorption process were calculated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3881–3885, 2004 相似文献
1000.
用膨化硝酸铵、硫磺、木粉和柴油作原材料,通过建立工业炸药配方设计及最优化数学模型,得到新型膨化硝胺硫横工业炸药配方。通过几种工业炸药的理论参数和实际爆炸性能的比较,得出新型膨化硝铵硫磺工业炸药具有低的成本和优良的爆炸性能。 相似文献