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41.
42.
Paul Barbic Leo Binder Susanne Voß Ferdinand Hofer Werner Grogger 《Monatshefte für Chemie / Chemical Monthly》2001,132(4):465-472
Summary. Thin-film electrodes allow the manufacturing of flat batteries of variable design. Their electric performance is better than
that of customary cells because of a larger contact area between anode and cathode and better utilization of the electrochemically
active materials. Bipolar thin-film electrodes for the rechargeable alkaline zinc/manganese dioxide system were assembled
using graphite-filled plastics (high-density polyethylene and polyisobutylene). In a different approach, extremely thin electrodes
were obtained using 25 μm thick foils made of non-conductive micro-porous polypropylene. The electroactive materials were
electrolytically deposited into the pores of the previously metallized foil, providing the required conductive connection
through the plastic matrix by themselves. Cycle behavior, cumulated capacities, and energies of batteries with up to two bipolar
units were measured. At this early stage of development, batteries based on graphite-filled polymer foils showed better results
with regard to storage capacity per unit area and to cycle life. Prototypes based on micro-porous polypropylene suffered from
the relatively small fraction of pore volume available for the deposition of active material (about 38%) and from current
collector corrosion.
Received May 30, 2000. Accepted December 18, 2000 相似文献
43.
44.
Ideals and filters in D-posets are defined. Therole of idempotent elements and atoms in the theory ofideals and filters is studied. 相似文献
45.
Dr. Ferdinand v. Arlt 《Monatshefte für Chemie / Chemical Monthly》1901,22(2):144-150
Ohne Zusammenfassung 相似文献
46.
Ferdinand Ihringer 《Journal of Algebraic Combinatorics》2017,46(2):263-274
We describe a general construction of strongly regular graphs from the collinearity graph of a finite classical polar spaces of rank at least 3 over a finite field of order q. We show that these graphs are non-isomorphic to the collinearity graphs and have the same parameters. For most of these parameters, the collinearity graphs were the only known examples, and so many of our examples are new. 相似文献
47.
Nuss G Saischek G Harum BN Volpe M Belaj F Mösch-Zanetti NC 《Inorganic chemistry》2011,50(24):12632-12640
Reaction of potassium tris(mercapto-tert-butylpyridazinyl)borate K[Tn(tBu)] with copper(II) chloride in dichloromethane at room temperature led to the diamagnetic copper boratrane compound [Cu{B(Pn(tBu))(3)}Cl] (Pn = pyridazine-3-thionyl) (1) under activation of the B-H bond and formation of a Cu-B dative bond. In contrast to this, stirring of the same ligand with copper(I) chloride in tetrahydrofuran (THF) gave the dimeric compound [Cu{Tn(tBu)}](2) (2) where one copper atom is coordinated by two sulfur atoms and one hydrogen atom of one ligand and one sulfur of the other ligand. Hereby, no activation of the B-H bond occurred but a 3-center-2-electron B-H···Cu bond is formed. The reaction of copper(II) chloride with K[Tn(tBu)] in water gave the same product 2, but a formal reduction of the metal center from Cu(II) to Cu(I) occurred. When adding tricyclohexyl phosphine to the reaction mixture of K[Tn(R)] (R = tBu, Me) and copper(I) chloride in MeOH, the distorted tetrahedral Cu complexes [Cu{Tn(R)}(PCy(3))] (R = tBu 3, Me 4) were formed. Compound 4 is exhibiting an "inverted" κ(3)-H,S,S, coordination mode. The copper boratrane 1 was further investigated by density functional theory (DFT) calculations for a better understanding of the M→B interaction involving the d(8) electron configuration of Cu. 相似文献
48.
Haas W Rath T Pein A Rattenberger J Trimmel G Hofer F 《Chemical communications (Cambridge, England)》2011,47(7):2050-2052
Cu(2)ZnSnSe(4) nanoparticles have high potential to be used as ink for printable solar cells. Using transmission electron microscopy we show that these nanoparticles exhibit a broad range of chemical heterogeneity. These results are contrary to the interpretation of previous experimental work and will have considerable impact on the development of these nanoparticles. 相似文献
49.
Ma Z Rissner F Wang L Heimel G Li Q Shuai Z Zojer E 《Physical chemistry chemical physics : PCCP》2011,13(20):9747-9760
Density functional theory calculations are used to investigate the electronic structure of pyridine-based self-assembled monolayers (SAMs) on an Au(111) surface. We find that, when using pyridine docking groups, the bonding-induced charge rearrangements are frequently found to extend well onto the molecular backbone. This is in contrast to previous observations for the chemisorption of other SAMs, e.g., organic thiolates on gold, and can be explained by a pinning of the lowest unoccupied states of the SAM at the metal Fermi-level. The details of the pinning process, especially the parts of the molecules most affected by the charge rearrangements, strongly depend on the length of the molecular backbone and the tail-group substituent. We also mention methodological shortcomings of conventional density functional theory that can impact the quantitative details regarding the circumstances under which pinning occurs and highlight a number of peculiarities associated with bond dipoles that arise from Fermi-level pinning. 相似文献
50.
Martin Fink Guy Desaulniers Markus Frey Ferdinand Kiermaier Rainer Kolisch François Soumis 《European Journal of Operational Research》2019,272(2):699-711
Synchronization of workers and vehicles plays a major role in many industries such as logistics, healthcare or airport ground handling. In this paper, we focus on operational ground handling planning and model it as an archetype of vehicle routing problems with multiple synchronization constraints, coined as “abstract vehicle routing problem with worker and vehicle synchronization” (AVRPWVS). The AVRPWVS deals with routing workers to ground handling jobs such as unloading baggage or refuelling an aircraft, while meeting each job’s time window. Moreover, each job can be performed by a variable number of workers. As airports span vast distances and due to security regulations, workers use vehicles to travel between locations. Furthermore, each vehicle, moved by a driver, can carry several workers. We propose two mathematical multi-commodity flow formulations based on time-space networks to efficiently model five synchronization types including movement and load synchronization. Moreover, we develop a branch-and-price heuristic that employs both conventional variable branching and a novel variable fixing strategy. We demonstrate that the procedure achieves results close to the optimal solution in short time when compared to the two integer models. 相似文献