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Journal of Radioanalytical and Nuclear Chemistry - A numerical radiation transport methodology for predicting gamma emission tomographs was developed utilizing the deterministic fuel burn-up...  相似文献   
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Ag is a promising catalyst for the production of carbon monoxide (CO) via the electrochemical reduction of carbon dioxide (CO2ER). Herein, we study the role of the formate (HCOO?) intermediate *OCHO, aiming to resolve the discrepancy between the theoretical understanding and experimental performance of Ag. We show that the first coupled proton‐electron transfer (CPET) step in the CO pathway competes with the Volmer step for formation of *H, whereas this Volmer step is a prerequisite for the formation of *OCHO. We show that *OCHO should form readily on the Ag surface owing to solvation and favorable binding strength. In situ surface‐enhanced Raman spectroscopy (SERS) experiments give preliminary evidence of the presence of O‐bound bidentate species on polycrystalline Ag during CO2ER which we attribute to *OCHO. Lateral adsorbate interactions in the presence of *OCHO have a significant influence on the surface coverage of *H, resulting in the inhibition of HCOO? and H2 production and a higher selectivity towards CO.  相似文献   
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Wearable sensing devices have transformed the hourly analysis of events such as body signals and environmental risks into real-time monitoring in minutes or seconds. Wearable sensors have facilitated the ability to obtain useful data by monitoring the physiological parameters and activities of an aided and a healthy individual. Wearable devices employ detectable biomarkers in the human body, such as in tears, saliva, interstitial fluid, sweat, and so on. These can deliver relevant information on human health, online activity monitoring, and therapeutic treatments. This section outlines the significance of sample types and associated biomarkers as indicators in the development and manufacturing of wearable biosensors. We have emphasized the most recent advances of wearables based on skin-like and textile, giving attention to personalized health monitoring to record signals of motion and physiological and body fluid investigation. Furthermore, this review categorizes wearable biosensors based on the sensing mechanism, electrochemical, optical, and mechanical. Additionally, the recent wearables related to the detection of the newly havoc-causing pandemic, COVID-19, and the future perspective for the development of much more advanced and potent wearable biosensors have been highlighted. The final section highlights unmet difficulties and gaps in wearable sensors in personalized therapy.  相似文献   
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Polyethylene glycol was found to be an inexpensive non-toxic and effective medium for one pot synthesis of high yields of decahydroacridine-1,8-diones in the presence of ceric ammonium nitrate as the catalyst. Moreover, the solvent can be recovered and reused.  相似文献   
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A pyrrole end-capped bipyridyl ligand incorporating a chiral handle exhibited high solid-state emission when compared to the achiral analogue 1b and to the racemic molecule 1c which allowed the design of a reusable fluorescent probe for the selective detection of Zn2+ under aqueous conditions.  相似文献   
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A series of 50 novel 7‐[2‐hydroxy‐3‐(1,2,3‐triazol‐1‐yl)propyloxy]‐3‐alkyl‐4‐methylcoumarins had been designed and synthesized in good to excellent yields via Cu(I)‐catalyzed 1,3‐dipolar cycloaddition reaction “click chemistry” of 7‐(3‐azido‐2‐hydroxypropyloxy)‐3‐alkyl‐4‐methylcoumarins with variety of acetylene derivatives. In turn, the precursor compound, that is, 7‐(3‐azido‐2‐hydroxypropyloxy)‐3‐alkyl‐4‐methylcoumarin, was synthesized by condensation of epichlorohydrin with 7‐hydroxy‐3‐alkyl‐4‐methylcoumarins followed by opening of the epoxide ring in the resulted 7‐epoxymethoxy‐3‐alkyl‐4‐methylcoumarins with sodium azide. All the synthesized compounds were unambiguously identified on the basis of their spectral data analyses (IR, 1H‐NMR, 13C‐NMR spectra, and HRMS).  相似文献   
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Room-temperature phosphorescence of metal and heavy atom-free organic molecules has emerged as an area of great potential in recent years. A rational design played a critical role in controlling the molecular ordering to impart efficient intersystem crossing and stabilize the triplet state to achieve room-temperature ultralong phosphorescence. However, in most cases, the strategies to strengthen phosphorescence efficiency have resulted in a reduced lifetime, and the available nearly degenerate singlet-triplet energy levels impart a natural competition between delayed fluorescence and phosphorescence, with the former one having the advantage. Herein, an organic helical assembly supports the exhibition of an ultralong phosphorescence lifetime. In contrary to other molecules, 3,6-phenylmethanone functionalized 9-hexylcarbazole exhibits a remarkable improvement in phosphorescence lifetime (>4.1 s) and quantum yield (11 %) owing to an efficient molecular packing in the crystal state. A right-handed helical molecular array act as a trap and exhibits triplet exciton migration to support the exceptionally longer phosphorescence lifetime.  相似文献   
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