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51.
用高分辨电子能量损失谱(HREELS)和热脱附谱(TDS)研究了\r\n乙酸在SmOx/Rh(100)模型表面上的吸附与分解.结果表明:低温下\r\n吸附乙酸时,SmOx的加入明显促进了乙酸分子中O-H键的断裂,从而有\r\n利于乙酸根的形成;升高表面温度,SmOx的存在促进了乙酸根中C-C键\r\n的断裂,有利于乙酸根的进一步分解.120K时,乙酸在SmOx/Rh(100\r\n)上主要以乙酸根的形式存在.225K时,乙酸根即可发生以生成CO为主\r\n的脱羧反应.在417和477K观察到受表面脱羧反应控制的CO2和H2的脱附\r\n峰.对反应的机理进行了讨论. 相似文献
52.
本文对传输网路管理(监控)中的传输监控网与电信管理网(TMN)的关系;准同步数字系统(PDH)与同步数字系统(SDH)的监迭管理以及传输监控网与电话管理网的关系进行了分析探讨。 相似文献
53.
Shuxian Zhou Chenghong Hu Weifeng Xu Xiaohui Mo Panliang Zhang Yu Liu Kewen Tang 《应用有机金属化学》2020,34(4):e5541
In this paper, zeolitic imidazolate framework-8 modified by the ethanediamine (NH2-ZIF-8) was employed for adsorbing Au (III) and Ag(I) from aqueous solutions. The adsorption capacities of NH2-ZIF-8 towards Au (III) and Ag(I) were found to be significantly affected by the pH values of the solution. The adsorption kinetics studies show that NH2-ZIF-8 presents a fast adsorption property towards metals, attaining 93% of adsorption equilibrium uptake for Au (III) within the first 30 min. This phenomenon can be ascribed to the coordination interaction between the amino group and Au (III). The thermodynamic data suggest that the adsorption of NH2-ZIF-8 towards Au (III) is endothermic process, while that for Ag(I) is exothermic. The maximum adsorption capacities of NH2-ZIF-8 toward Au (III) and Ag(I) can be achieved to 357 mg·g−1 and 222.25 mg·g−1, respectively. The metal ions interference results show that Cu (II) and Ni (II) hardly have no interference on Au (III) adsorption in e-waste containing 1500 mg·l−1 Cu (II),100 mg·l−1 Ni (II) and 10 mg·l−1 Au (III); while for Ag(I), Cd (II) and Zn (II) have little interference on Ag(I) adsorption in the hybrid solutions containing Ag(I), Ni (II), Cd (II) and Zn (II) with equal concentration (50 mg·l−1), but Ni (II) interference most. The XPS study shows that partial Au (III) was reduced to Au(I), and that Ag(I) was completely reduced to Ag(0) during the adsorption process. The abundant of active sites of NH2-ZIF-8 containing C=N, N-H, and Zn-OH groups play a key role in the adsorption of Au (III) and Ag(I). In addition, electrostatic interaction can be responsible for the adsorption of Au (III) by NH2-ZIF-8. The regeneration experiments results show that the adsorption capacities of NH2-ZIF-8 towards Au (III) and Ag(I) can maintain after three cycles. This work provides a reliable method to improve the adsorption kinetics for metal ions. 相似文献
54.
Huang Mengting Xu Cunying Wang Xiang Liu Hai Wang Shuxian Ren Xiangyu Hua Yixin Zhang Qibo Li Yan 《Journal of Solid State Electrochemistry》2020,24(5):1175-1184
Journal of Solid State Electrochemistry - The effect of Cu(I) ions on the electrodeposition of zinc from ChCl-urea-ZnO deep eutectic solvent (DES) was investigated through electrochemical... 相似文献
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56.
Jinghua Chen Jia Lin Xi Zhang Shuxian Cai Dongzhi Wu Chunyan Li Sheng Yang Jing Zhang 《Analytica chimica acta》2014
Non-invasive early diagnosis of breast cancer is the most effective way to improve the survival rate and increase more chances of breast-conserving. In this paper, we developed a label-free fluorescent biosensor based on nuclease assisted target recycling and Thioflavin T-induced quadruplex formation for short DNA species of c-erbB-2 detection in saliva. By employing the strategy, the sensor can detect as low as 20 fM target DNA with high discrimination ability even against single-base mismatch sequence. To the best of our knowledge, the proposed sensor is the first attempt to apply Thioflavin T that possesses outstanding structural selectivity for G-quadruplex in DNA amplification techniques, which may represent a promising path toward direct breast cancer detection in saliva at the point of care. 相似文献
57.
Minliang Liu Yuhu Zhang Xiaohong Zhou Yingxiang Guo Zhong Liu Xiangguo Lei Jianjun He Yong Zheng Wanju Luo Lihua Zhu Shuxian Wen 《中国科学G辑(英文版)》2003,46(3):330-336
High-spin states in141Nd have been studied using in-beam γ-ray spectroscopic techniques via the130Te(16O, 5nγ)141Nd reaction. The level scheme of141Nd has been extended up to an excitation energy of 7614.5 keV including 12 new γ rays deexciting 15 new levels. According
to particle-vibrator coupling and semi-empirical shell model calculations, the level structure of141Nd can be well interpreted by coupling an h11/2 neutron-hole to the respective excited states in142Nd core. 相似文献
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59.
解大系统稳定性的积分方程法 总被引:4,自引:0,他引:4
本文通过分解积分方程组,并建立积分方程法比较原理,化大系统为低维系统,进而讨论了带时滞的时变大系统的稳定性,给出了新的结果,这一方法也可以用来讨论其它类型大系统的稳定性问题. 相似文献
60.
Graphene‐Fe3O4 as a magnetic solid‐phase extraction sorbent coupled to capillary electrophoresis for the determination of sulfonamides in milk
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Zhaoqian Li Yazhen Li Mengyu Qi Shuxian Zhong Weiping Wang Ai‐Jun Wang Jianrong Chen 《Journal of separation science》2016,39(19):3818-3826
Graphene‐Fe3O4 nanoparticles were prepared using one‐step solvothermal method and characterized by X‐ray diffraction, FTIR spectroscopy, scanning electron microscopy, and vibrating sample magnetometry. The results demonstrated that Fe3O4 nanoparticles were homogeneously anchored on graphene nanosheets. The as‐synthesized graphene‐Fe3O4 nanoparticles were employed as sorbent for magnetic solid‐phase extraction of sulfonamides in milk prior to capillary electrophoresis analysis. The optimal capillary electrophoresis conditions were as follows: 60 mmol/L Na2HPO4 containing 2 mmol/L ethylenediaminetetraacetic acid disodium salt and 24% v/v methanol as running buffer, separation voltage of 14 kV, and detection wavelength of 270 nm. The parameters affecting extraction efficiency including desorption solution, the amount of graphene‐Fe3O4 nanoparticles, extraction time, and sample pH were investigated in detail. Under the optimal conditions, good linearity (5–200 μg/L) with correlation coefficients ≥0.9910 was obtained. The limits of detection were 0.89–2.31 μg/L. The relative standard deviations for intraday and interday analyses were 4.9–8.5 and 4.0–9.0%, respectively. The proposed method was successfully applied to the analysis of sulfonamides in milk samples with recoveries ranging from 62.7 to 104.8% and relative standard deviations less than 10.2%. 相似文献