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111.
Dr. Rafaela Gladysz Dr. Johannes Vrijdag Dr. Dries Van Rompaey Prof. Dr. Anne-Marie Lambeir Prof. Dr. Koen Augustyns Prof. Dr. Hans De Winter Prof. Dr. Pieter Van der Veken 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(53):12380-12393
Target-guided synthesis (TGS) has emerged as a promising strategy in drug discovery. Although reported examples of TGS generally involve two-component reactions, there is a strong case for developing target-guided versions of three-component reactions (3CRs) because of their potential to deliver highly diversified druglike molecules. To this end, the Groebke–Blackburn–Bienaymé reaction was selected as a model 3CR. We recently reported a series of druglike urokinase inhibitors, and these serve as reference compounds in the present study. Due to the limited number of literature reports on target-guided 3CRs, multiple experimental parameters were optimized here. Most challenging was the formation of imine intermediates under near-physiological conditions. This aspect was addressed by exploring chemical imine stabilization strategies. Notably, imines are also crucial intermediates of other 3CRs. Such systematic studies are strongly required for further development of the TGS domain but are largely absent in the literature. Hence, this work is intended as a reference for future multicomponent-based TGS studies. 相似文献
112.
113.
It is shown that the current-voltage relation of AgGaS surface barriers can be described within the diffusion theory for Schottky barriers, corrected for the image-force lowering of the barrierheight. The barrier lowering is independently determined from photo-response measurements which yield an image-force dielectric constant of 5.0. 相似文献
114.
Analyzing powers for these charge symmetric reactions were measured at low energies where symmetry breaking effects due to the Coulomb interaction should be enhanced. Differences in the magnitudes exist and must be explained if charge symmetry holds; a simple energy shift, proposed earlier, is not adequate for this purpose. 相似文献
115.
Jari Kyngäs Kimmo Nurmi Nico Kyngäs George Lilley Thea Salter Dries Goossens 《The Journal of the Operational Research Society》2017,68(8):973-982
Generating a schedule for a professional sports league is an extremely demanding task. Good schedules have many benefits for the league, such as higher attendance and TV viewership, lower costs and increased fairness. The Australian Football League is particularly interesting because of an unusual competition format integrating a single round-robin tournament with additional games. Furthermore, several teams have multiple home venues and some venues are shared by multiple teams. This paper presents a 3-phase process to schedule the Australian Football League. The resulting solution outperforms the official schedule with respect to minimizing and balancing travel distance and breaks, while satisfying more requirements. 相似文献
116.
Vande Velde CM Collas A De Borger R Blockhuys F 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(3):912-919
(E,E)-1-[2-(4-Nitrophenyl)ethenyl]-4-[2-(2,4-dimethoxyphenyl)ethenyl]benzene was characterised by X-ray diffraction and shown to be dynamically disordered at room temperature. The structure was re-determined over a range of temperatures to infer the thermodynamic parameters related to this disorder. A phase transition of third order according to the Ehrenfest classification scheme was discovered. To the best of our knowledge, this is the first experimentally observed phase transition of formal third order. It can be explained by the involvement of long-range lattice vibrations. 相似文献
117.
De Bock L Vande Casteele SR Mulliez SM Boussery K Van Bocxlaer JF 《Journal of chromatography. A》2011,1218(6):793-801
For the determination of the in vitro cytochrome P450 activity in microsomes, a quantification method for the probe metabolites, formed during incubation, is required. Due to insufficient sensitivity of a previously developed high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for some of the metabolites, a fast and easy derivatization method with pyridine-3-sulfonyl chloride (PS) is described. Acetaminophen (CYP1A2), dextrorphan (CYP2D6), hydroxy-chlorzoxazone (CYP2E1) and hydroxy-mephenytoin (CYP2C19) can be derivatized because of the presence of a phenolic OH, whereas hydroxy-midazolam (CYP3A4) and hydroxy-tolbutamide (CYP2C9) remain unchanged. As PS improves the ionization efficiency in the positive electrospray ionization (ESI) mode, the sensitivity of the detection is improved significantly and meets requirements for the activity determination. Native negative electrospray type molecules, moreover, become positive ESI candidates. The direct derivatization in the aqueous incubation medium, without any other sample pre-treatment steps, such as evaporation or extraction, makes this procedure easy to perform. The method using 20s microwave irradiation was shown to equal a 10min reaction in a 60°C heating block, consequently simplifying and shortening the process. Collision induced fragmentation of the derivatives resulted in at least one native compound, rather than derivative, specific product ion, thereby improving the selectivity of the method in the multiple reaction monitoring mode. The HPLC-MS/MS method was validated, and was demonstrated to be sensitive, selective, precise and accurate. The absence of a relative matrix effect was established, notwithstanding that an absolute matrix effect was observed. The analysis of a sample after microsomal incubation, from which some of the metabolites could not be quantified using the method without derivatization, proved the usefulness of the method. 相似文献
118.
Koen Binnemans Dries Moors Tatjana N. Parac-Vogt Rik Van Deun Dirk Hinz-Hübner Gerd Meyer 《Liquid crystals》2013,40(9):1209-1216
Liquid crystalline complexes [Ln(LH)3Cl3] have been synthesized, where Ln is a trivalent lanthanide ion (Pr-Lu, except Pm) and where LH is the Schiff's base ligand N-octadecyl4-tetradecyloxysalicylaldimine. Although the ligand does not exhibit mesomorphism, the complexes do (SmA phase). The mesophase behaviour of these compounds has been investigated by polarizing optical microscopy, differential scanning calorimetry and high temperature X-ray diffraction. The lanthanide complexes have much higher melting and clearing points than comparable complexes with nitrate or dodecyl sulphate counterions. In addition, the transition temperatures are virtually independent of the type of lanthanide ion. This behaviour is opposite to that observed for similar complexes with nitrate counterions [Ln(LH)3(NO3)3]. The differences in temperature dependence can be related to structural differences. Whereas in the nitrate complexes the Schiff's base ligand binds in a zwitterionic form, two-dimensional 1H NMR correlation spectroscopy (COSY) of [Lu(LH)3Cl3] gives an indication that in the chloride complexes, besides coordination via the oxygen of molecules in the zwitterionic form, some of the Schiff's base ligands bind in a bidentate fashion (via the phenolic oxygen and the imine nitrogen). 相似文献
119.
Ronald G. Cavell Larry Vande Griend 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):89-92
Abstract Three new six-coordinate trifluoromethylfluorophosphorus carbamates F4-n(CF3)nPO2CN(CH3)2 (n = 1, 2, 3) have been prepared by reaction of trimethylsilylcarbamate with the appropriate fluorophosphorane. All products appear to be six-coordinate as indicated by characteristic high field 31P nmr chemical shifts and in some cases are fluxional. Two isomers are observed in the nmr spectra of the compound with n = 1. Only one structure is formed in the n = 2 and 3 cases. The crystal and molecular structure of F(CF3)3PO2CN(CH3)2 revealed a six-coordinate structure with the unique F in the plane containing the chelated carbamate. 相似文献
120.
Dries R. Goossens Jeroen Beliën Frits C. R. Spieksma 《Annals of Operations Research》2012,194(1):223-240
Recently, most clubs in the highest Belgian football division have become convinced that the format of their league should
be changed. Moreover, the TV station that broadcasts the league is pleading for a more attractive competition. However, the
clubs have not been able to agree on a new league format, mainly because they have conflicting interests. In this paper, we
compare the current league format, and three other formats that have been considered by the Royal Belgian Football Association.
We simulate the course of each of these league formats, based on historical match results. We assume that the attractiveness
of a format is determined by the importance of its games; our importance measure for a game is based on the number of teams
for which this game can be decisive to reach a given goal. Furthermore, we provide an overview of how each league format aligns
with the expectations and interests of each type of club. 相似文献