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151.
Izabela Janowska Keitaro Nakatani Marcin Walak 《Journal of organometallic chemistry》2006,691(3):323-330
Second-order nonlinear optical chromophores incorporating the ferrocenyl group as an electron donor and 3-dicyanomethylidene-1-indanone and 1,3-bis(dicyanomethylidene)indane acceptor groups, connected by a conjugated polyenic bridge of varied length (2[n] and 3[n], respectively) have been synthesized. The electronic absorption spectra of these compounds display in the visible region bands attributable to π-π* and metal-to ligand charge transfer (MLCT) transitions. The energies of these transitions are close to those reported earlier for ferrocenyl D-π-A chromophores with the strongest acceptor groups, e.g., with the 3-dicyanomethylidene-2,3-dihydrobenzothiophene-1,1-dioxide group (1[n]) [V. Alain, M. Blanchard-Desce, C.-T. Chen, S.R. Marder, A. Fort, M. Barzoukas, Synt. Met. 81 (1996) 133]. The solid-state structure of 2[3], determined by X-ray diffraction shows a significant reduction of the bond length alternation (BLA), 0.05 Å, suggesting high first hyperpolarizability. However, a centrosymmetrical packing of molecules of this compound in the crystal excludes its second harmonic generation ability. The μβ values of 2[n] and 3[n], determined by the EFISH technique at 1907 nm are high and increase with the increasing length of the conjugated π-bridge. The highest value of μβ (8720 × 10−48 esu) was determined for 3[4], which is close to that reported for 1[4] (11 200 × 10−48 esu), the highest value found for a ferrocenyl D-π-A chromophore until now. 相似文献
152.
153.
This paper presents the problem of control of anti-aircraft missile launcher mounted on a moving carrier-vehicle. Direct excitations on the vehicle from the road cause adverse vibrations of the launcher. In order to increase the precision of the guiding system in the conditions of self-propelled movement of the setup on a bumpy road, the adaptive control algorithm was proposed. Some research results of computer simulation are presented in a graphical form. 相似文献
154.
Izabela Wiater Katarzyna Madej Andrzej Parczewski Maria Kała 《Mikrochimica acta》1998,129(1-2):121-126
The TLC separation of twelve drugs from three pharmaceutical groups: phenothiazines and tri and tetracyclic antidepressants is presented. Three kinds of eluents and two types of solid phases (RP 18 and Silica gel 60) were used. The composition of mobile phases was optimized by the Simplex method. In the basic optimization criterion the differences betweenR
f values of the spots corresponding to individual drugs were taken into account. An auxiliary criterion was based on the colour of the spots, which were developed with appropriate reagents. The experimental data obtained during optimization were interpreted using a matrix presentation. In the optimal conditions the differences between positions of the spots enable identification of ten of the examined drugs, but two remained unresolved.Parts of this paper were presented at the 33rd International Congress on Forensic Toxicology, August 27–31, 1995, Thessaloniki, Greece, and the Vth Polish Conference on Analytical Chemistry, September 3–8, 1995, Gdansk 相似文献
155.
Mariusz Kaleta Włodzimierz Ogryczak Eugeniusz Toczyłowski Izabela Żółtowska 《Annals of Operations Research》2003,121(1-4):79-104
As an active participant of a competitive energy market, the generator (the energy supplier) challenges new management decisions being exposed to the financial risk environment. There is a strong need for the decision support models and tools for energy market participants. This paper shows that the stochastic short-term planning model can be effectively used as a key analytical tool within the decision support process for relatively small energy suppliers (price-takers). A self-scheduling method for the thermal units on the energy market is addressed. A schedule acquired for given preferences can be used as a desired pattern for bidding process. The uncertainty of the market prices is modeled by a set of possible scenarios with assigned probabilities. Several risk criteria are introduced leading to a multiple criteria optimization problem. The risk criteria are well appealing and easily computable (by means of linear programming) but they meet the formal risk aversion standards. The aspiration/reservation based interactive analysis applied to the multiple criteria problem allows us to find an efficient solution (generation scheme) well adjusted to the generator preferences (risk attitude). 相似文献
156.
Izabela M. Barszczewska-Rybarek 《International Journal of Polymer Analysis and Characterization》2013,18(2):93-104
In this work, the correlation between experimental and theoretical values of density (ρ) and glass transition temperature (T g ) of dimethacrylate polymer networks is elaborated. The developed methodologies are based on the additive principle of the known monomer chemical structures. The predicted values of ρ differed by a maximum of 1% from the experimental values. The methodology developed for T g prediction is based on the assumption that dimethacrylate structural units are treated as main chains between ?CH2C(CH3)? tri-functional volumeless cross-links. Three-quarters of the calculated T g values differed less than 20 K from the experimental ones. 相似文献
157.
Magorzata Szczesio Katarzyna Gobis Izabela Korona-Gowniak Ida Mazerant-Politowicz Dagmara Ziembicka Henryk Foks Marek Gwka Andrzej Olczak 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(7):673-680
Four new picolinohydrazonamide derivatives, namely, 6‐methyl‐N′‐(morpholine‐4‐carbonothioyl)picolinohydrazonamide, C12H17N5OS, 6‐chloro‐N′‐(morpholine‐4‐carbonothioyl)picolinohydrazonamide methanol monosolvate, C11H14ClN5OS·CH3OH, 6‐chloro‐N′‐(4‐phenylpiperazine‐1‐carbonothioyl)picolinohydrazonamide, C17H19ClN6S, and 6‐chloropicolinohydrazonamide, C6H7ClN4, have been synthesized and characterized by NMR spectroscopy and single‐crystal low‐temperature X‐ray diffraction. In addition, their antibacterial and anti‐yeast activities have been determined. The first three compounds adopt the zwitterionic form in the crystal structure regardless of the presence or absence of solvent molecules in the structure. They also adopt the same symmetry, i.e. P21/c (P21/n), unlike the fourth structure which is chiral and has the space group P212121. For all the studied cases, intermolecular N—H…O and N—H…N hydrogen bonds play an essential role in the formation of the structures. 相似文献
158.
“What Doesn’t Kill You Makes You Stronger”: Future Applications of Amyloid Aggregates in Biomedicine
Sherin Abdelrahman Mawadda Alghrably Joanna Izabela Lachowicz Abdul-Hamid Emwas Charlotte A. E. Hauser Mariusz Jaremko 《Molecules (Basel, Switzerland)》2020,25(22)
Amyloid proteins are linked to the pathogenesis of several diseases including Alzheimer’s disease, but at the same time a range of functional amyloids are physiologically important in humans. Although the disease pathogenies have been associated with protein aggregation, the mechanisms and factors that lead to protein aggregation are not completely understood. Paradoxically, unique characteristics of amyloids provide new opportunities for engineering innovative materials with biomedical applications. In this review, we discuss not only outstanding advances in biomedical applications of amyloid peptides, but also the mechanism of amyloid aggregation, factors affecting the process, and core sequences driving the aggregation. We aim with this review to provide a useful manual for those who engineer amyloids for innovative medicine solutions. 相似文献
159.
Izabela Czelu?niak 《Journal of organometallic chemistry》2011,696(18):3023-3028
The reactions of tin tetrachloride and four terminal alkynes (PhCCH, tBuCCH, nBuCCH, HOCH2CCH), norbornene, and norbornadiene in dichloromethane or chloroform solution lead to the formation of stannylation products, which were characterized by 1H, 13C and 119Sn NMR spectroscopy. Virtually complete α-regioselectivity was obtained in reaction of all four alkynes without any effect of the relative steric bulk of the substituent R at the triple bond of alkyne RCβCαH. The reaction of norbornene and norbornadiene with SnCl4 is stereoselective, giving an exo stannylation product. 相似文献
160.
Grząbka-Zasadzińska Aleksandra Ratajczak Izabela Król Katarzyna Woźniak Magdalena Borysiak Sławomir 《Cellulose (London, England)》2021,28(9):5745-5759
Cellulose - In this work, the influence of the supermolecular structure of cellulosic fillers in chitosan matrix on the process of adsorption of calcium, magnesium and iron metal ion was analyzed,... 相似文献