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描述CCD器件在HL-1M多发弹丸加料实验中观测短暂消融云的应用结果,并介绍一种有特色的触发方式 用弹丸自身辐射的氢a 射线启动相机。实验证明:这种安排能取得大量照片,CCD成功地应用于弹丸消融过程观测, 图片处理分析后获得消融云形状、结构和辐射强度分布等。可以相信CCD诊断方法不但加深了弹丸加料的认识,也会促进军事工程相关瞬态高速过程的研究。 相似文献
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喷雾颗粒的浓度、粒径等多参数的同时测量是研究喷雾的关键. 对应用全场彩虹技术测量双组分液滴的浓度及粒径分布进行了研究. 基于改进的Nussenzweig理论,对液滴折射率和粒径分布采用无分布函数算法进行最优化求解, 然后通过折射率与浓度的关系反推液滴浓度.用模拟全场彩虹信号对该算法进行了验证, 该算法可准确反演具有单峰分布、双峰分布粒径特征的液滴群的折射率与粒径分布. 并对体积分数从0%到100%的乙醇溶液喷雾进行了实验测量, 结果表明,所测得折射率与理论值符合,粒径分布稳定.该技术在喷雾浓度测量方面具有广阔的应用前景.
关键词:
全场彩虹技术
折射率
粒径
组分 相似文献
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用相对论多组态 (HXR)方法 ,详细计算了类Ne氪离子 4d 2 p类Na 3l4l′双电子伴线波长和强度因子 ,并模拟了实验光谱 ,解释了最新利用激光气体靶产生的 0 .5 2 5~ 0 .5 5 5nm范围的氪X Ray光谱 ,计算结果与实验符合得相当好。此外 ,还讨论了组态相互作用对双电子伴线结构的影响。 相似文献
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Na[cyclo‐(P5tBu4)] ( 1 ) reacts with [FeBr2(CO)4] (2:1) to give the first homoleptic iron(II) complex [Fe{cyclo‐(P5tBu4)}2] ( 2 ) containing two tridentate cyclo‐(P5tBu4)– ligands. Thermolysis of 2 up to 500 °C produces a new phosphorus‐rich iron phosphide, calculated as FeP6 according to the mass change. 相似文献
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Aslhan SÜMER 《Turkish Journal of Chemistry》2020,44(4):1016
The physical and chemical properties of bimetallic nanoparticles can be optimized by tuning the particle composition. In this study, we identified CO adsorption and dissociation energetics on five Pt-Mo nanoparticles at different concentrations, the lowest energy Pt7, Pt6Mo, Pt5Mo2, Pt4Mo3, and Mo7 clusters. We have shown that the CO adsorption and dissociation energies and preferred CO adsorption sites are largely dependent on the composition of the nanoparticles. As the Mo concentration increases, the strength of the C-O internal bond in the adsorption complex decreases, as indicated by a decrease in the C-O stretching frequency. Also, more Mo sites in the nanoparticle become available for CO adsorption, and the preferred CO adsorption site switches from Pt to Mo. For these reasons, dissociation of CO is energetically favorable on Pt4Mo3 and Mo7. On both compositions, we have shown that the dissociation paths begin with CO adsorbed on a Mo site in a multifold configuration, in particular in a tilted configuration. These findings provide insight on the effects of the composition on the chemical and catalytical properties of Pt-Mo nanoparticles, thereby guiding future experiments on the synthesis of nanoparticles, especially those that may be suitable for various desired applications containing CO. 相似文献
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Ozmen UO Olgun G 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(3):641-645
Prophane sulfonic acid hydrazide (psh: CH(3)CH(2)CH(2)SO(2)NHNH(2)) derivatives as salicylaldehydeprophanesulfonylhydrazone (salpsh), 5-methylsalicylaldehydeprophanesulfonylhydrazone (5-msalpsh), 2-hydroxyacetophenoneprophanesulfonylhydrazone (afpsh), 5-methyl-2-hydroxyacetophenoneprophanesulfonylhydrazone (5-mafpsh) and their Ni(II) complexes have been synthesized. The structure of these compounds has been investigated by using elemental analysis, FTIR, (1)H NMR, LC/MS, UV-vis spectrophotometric method, magnetic susceptibility and conductivity measurements. The complexes were found to have general compositions [NiL2]. Square-planer structures are proposed for the Ni(II) complexes on the basis of magnetic evidence, electronic spectra and TGA data. Bacterial activities of sulfonyl hydrazone compounds were studied against gram-positive bacteria: Staphylococcus aureus, Bacillus subtilis, Bacillus magaterium and gram-negative bacteria: Salmonella enteritidis, Escherichia coli by using minimum inhibitory concentrations (MICs) method. 相似文献
10.
Nazl Turan Yücel Ümmühan Kandemir Ümide Demir
zkay
zgür Devrim Can 《Molecules (Basel, Switzerland)》2021,26(11)
Vortioxetine is a multimodal antidepressant drug that affects several brain neurochemicals and has the potential to induce various pharmacological effects on the central nervous system. Therefore, we investigated the centrally mediated analgesic efficacy of this drug and the mechanisms underlying this effect. Analgesic activity of vortioxetine (5, 10 and 20 mg/kg, p.o.) was examined by tail-clip, tail-immersion and hot-plate tests. Motor performance of animals was evaluated using Rota-rod device. Time course measurements (30–180 min) showed that vortioxetine (10 and 20 mg/kg) administrations significantly increased the response latency, percent maximum possible effect and area under the curve values in all of the nociceptive tests. These data pointed out the analgesic effect of vortioxetine on central pathways carrying acute thermal and mechanical nociceptive stimuli. Vortioxetine did not alter the motor coordination of mice indicating that the analgesic activity of this drug was specific. In mechanistic studies, pre-treatments with p-chlorophenylalanine (serotonin-synthesis inhibitor), NAN-190 (serotonin 5-HT1A receptor antagonist), α-methyl-para-tyrosine (catecholamine-synthesis inhibitor), phentolamine (non-selective α-adrenoceptor blocker), and naloxone (non-selective opioid receptor blocker) antagonised the vortioxetine-induced analgesia. Obtained findings indicated that vortioxetine-induced analgesia is mediated by 5-HT1A serotonergic, α-adrenergic and opioidergic receptors, and contributions of central serotonergic and catecholaminergic neurotransmissions are critical for this effect. 相似文献