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排序方式: 共有256条查询结果,搜索用时 281 毫秒
101.
Dr. Guixiang Li Dr. Yalei Hu Prof. Dr. Meng Li Ying Tang Zuhong Zhang Dr. Artem Musiienko Qing Cao Fatima Akhundova Jinzhao Li Karunanantharajah Prashanthan Dr. Fengjiu Yang Patryk Janasik Augustine N. S. Appiah Sergei Trofimov Nikolaos Livakas Shengnan Zuo Luyan Wu Luyao Wang Dr. Yuqian Yang Dr. Benjamin Agyei-Tuffour Dr. Rowan W. MacQueen Dr. Boris Naydenov Dr. Thomas Unold Prof. Dr. Eva Unger Dr. Ece Aktas Prof. Dr. Siegfried Eigler Prof. Dr. Antonio Abate 《Angewandte Chemie (International ed. in English)》2023,62(39):e202307395
Stability issues could prevent lead halide perovskite solar cells (PSCs) from commercialization despite it having a comparable power conversion efficiency (PCE) to silicon solar cells. Overcoming drawbacks affecting their long-term stability is gaining incremental importance. Excess lead iodide (PbI2) causes perovskite degradation, although it aids in crystal growth and defect passivation. Herein, we synthesized functionalized oxo-graphene nanosheets (Dec-oxoG NSs) to effectively manage the excess PbI2. Dec-oxoG NSs provide anchoring sites to bind the excess PbI2 and passivate perovskite grain boundaries, thereby reducing charge recombination loss and significantly boosting the extraction of free electrons. The inclusion of Dec-oxoG NSs leads to a PCE of 23.7 % in inverted (p-i-n) PSCs. The devices retain 93.8 % of their initial efficiency after 1,000 hours of tracking at maximum power points under continuous one-sun illumination and exhibit high stability under thermal and ambient conditions. 相似文献
102.
A method is described for the simultaneous determination of two short-chained amides, acrylamide and acetamide (classified by the International Agency for Research on Cancer as probable and possible human carcinogens, respectively), in total particulate matter using gas chromatography-on-column injection and mass spectrometric detection. Sample preparation is kept to a minimum, and the proposed analytical procedure proves to be fast, sensitive, and precise. Validation studies show good linearity with a regression coefficient of r2=.000 for both compounds. Quantitation limits are 32 ng/mL for acrylamide and 70 ng/mL for acetamide. In the particulate phase of mainstream smoke from the University of Kentucky Reference Cigarette 2R4F, 2.3 microg/cig acrylamide and 4.7 microg/cig acetamide are found; no acetamide and only .0074 microg/cig acrylamide is found in the gas phase. Possible mechanisms of formation in cigarette smoke are discussed. 相似文献
103.
Joerg Harloff 《Journal of organometallic chemistry》2008,693(7):1283-1291
The reaction pathway for the formation of the trimethylsiloxysilyllithium compounds (Me3SiO)RR′SiLi (2a: R = Et, 2b: R = iPr, 2c: R = 2,4,6-Me3C6H2 (Mes); 2a-c: R′ = Ph; 2d: R = R′ = Mes) starting from the conversion of the corresponding trimethylsiloxychlorosilanes (Me3SiO)RR′SiCl (1a-d) in the presence of excess lithium in a mixture of THF/diethyl ether/n-pentane at −110 °C was investigated.The trimethylsiloxychlorosilanes (Me3SiO)RPhSiCl (1a: R = Et, 1b: R = iPr, 1c: R = Mes) react with lithium to give initially the trimethylsiloxysilyllithium compounds (Me3SiO)RPhSiLi (2a-c). These siloxysilyllithiums 2 couple partially with more trimethylsiloxychlorosilanes 1 to produce the siloxydisilanes (Me3SiO)RPhSi-SiPhR(OSiMe3) (Ia-c), and they undergo bimolecular self-condensation affording the trimethylsiloxydisilanyllithium compounds (Me3SiO)RPhSi-RPhSiLi (3a-c). The siloxydisilanes I are cleaved by excess of lithium to give the trimethylsiloxysilyllithiums (Me3SiO)RPhSiLi (2). In the case of the two trimethylsiloxydisilanyllithiums (Me3SiO)RPhSi-RPhSiLi (3a: R = Et, 3b: R = iPr) a reaction with more trimethylsiloxychlorosilanes (Me3SiO)RPhSiCl (1a, 1b) takes place under formation of siloxytrisilanes (Me3SiO)RPhSi-RPhSi-SiPhR(OSiMe3) (IIa: R = Et, IIb: R = iPr) which are cleaved by lithium to yield the trimethylsiloxysilyllithiums (Me3SiO)RPhSiLi (2a, 2b) and the trimethylsiloxydisilanyllithiums (Me3SiO)RPhSi-RPhSiLi (3a, 3b). The dimesityl-trimethylsiloxy-silyllithium (Me3SiO)Mes2SiLi (2d) was obtained directly by reaction of the trimethylsiloxychlorosilane (Me3SiO)Mes2SiCl (1d) and lithium without formation of the siloxydisilane intermediate. Both silyllithium compounds 2 and 3 were trapped with HMe2SiCl giving the products (Me3SiO)RR′Si-SiMe2H and (Me3SiO)RPhSi-RPhSi-SiMe2H. 相似文献
104.
105.
Dr. Roland Frach Patrick Kibies Saraphina Böttcher Tim Pongratz Steven Strohfeldt Simon Kurrmann Dr. Joerg Koehler Martin Hofmann Prof. Dr. Werner Kremer Prof. Dr. Hans Robert Kalbitzer Prof. Dr. Oliver Reiser Prof. Dr. Dominik Horinek Prof. Dr. Stefan M. Kast 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(39):11887-11887
106.
107.
Robin Hoeher Thomas Raidt Maik Rose Frank Katzenberg Joerg C. Tiller 《Journal of Polymer Science.Polymer Physics》2013,51(13):1033-1040
Shape memory polymers (SMPs) are an important class of smart materials. So far the focus of such polymers was to find suited triggers for various application fields. Thus, the potential of most of these macromolecular networks regarding their maximally storable strain capability was not explored. In this study, the polyethylenes HDPE, LDPE, and ethylene‐1‐octene (EOC) were systematically investigated with respect to their strain storage potential. To achieve maximum strains, the polymers were chemically cross‐linked in such a way that they are at the borderline between thermoplastics and elastomers. All investigated polymers showed higher strain storage than literature reported systems and exhibited excellent shape memory parameters. The highest stored strain was found for networks of EOC with fully recoverable 1400%. Interestingly, this value could not be enlarged by using EOCs with higher molecular weight, which is probably due to increasing content of entanglements as confirmed by Mooney‐Rivlin. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 , 51, 1033–1040 相似文献
108.
Mark S. Bannon Aida López Ruiz Karen Corrotea Reyes Miriam Marquez Zahra Wallizadeh Mohammad Savarmand Connor A. LaPres Joerg Lahann Kathleen McEnnis 《Particle & Particle Systems Characterization》2021,38(6):2100016
A successful drug delivery system must overcome complex biological barriers. For particles injected into the blood, one of the first and most critical barriers pertains to blood stability to circulate through the human body. To effectively design drug delivery vehicles, interactions between the particles and blood, as well as the aggregation behavior, must be understood. This work presents a method to analyze particle size and aggregation in blood plasma using a commercially available nanoparticle tracking analysis (NTA) system. As a model system, fluorescently labeled polystyrene nanoparticles are incubated in goat blood plasma and analyzed using NTA. The particles incubated in plasma are found to have a protein corona that is larger than what has been observed by dynamic light scattering (DLS) in diluted plasma. Particles that are decorated with a PEG layer are also found to have large protein coronas in undiluted plasma. Because NTA is based on a unique visualization method, large multicomponent aggregates could be observed and quantified in a manner not feasible with other techniques. PEGylation of the particles is found to decrease the multicomponent aggregation from 1000 ± 200 particles for unmodified to 200 ± 30 particles for 1K PEGylated per 1 × 105 total particles. 相似文献
109.
110.
Resonant regeneration in the sub-quantum regime – A demonstration of fractional quantum interference
Light shining through wall experiments (in the optical as well as in the microwave regime) are a powerful tool to search for light particles coupled very weakly to photons such as axions or extra hidden sector photons. Resonant regeneration, where a resonant cavity is employed to enhance the regeneration rate of photons, is one of the most promising techniques to improve the sensitivity of the next generation of experiments. However, doubts have been voiced if such methods work at very low regeneration rates where on average the cavity contains less than one photon. In this Letter we report on a demonstration experiment using a microwave cavity driven with extremely low power, to show that resonant amplification works also in this regime. In accordance with standard quantum mechanics this is a demonstration that interference also works at the level of less than one quantum. As an additional benefit this experiment shows that thermal photons inside the cavity cause no adverse effects. 相似文献