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911.
Neil Tarrant 《Ambix》2018,65(3):210-231
In the latter half of the sixteenth century the Roman Inquisition developed criteria to prosecute a series of operative arts, including various forms of divination and magic. Its officials had little interest in alchemy. During that period the Roman Inquisition tried few people for practising alchemy, and it was rarely discussed in official documents. Justifications for prosecuting alchemists did exist, however. In his influential handbook, Directorium inquisitorum, the fourteenth-century inquisitor Nicholas Eymerich had developed a clear rationale for the investigation and prosecution of alchemists as heretics. His position was endorsed in the 1570s by Francisco Peña in his commentary on Eymerich’s handbook. In this article I explore the reasons why alchemy held this ambiguous status. I argue that members of the Dominican Order developed two traditions of thinking about alchemy from Aquinas’s thought. The first, and closest to Aquinas’s own belief, held that alchemy was a natural art that posed no danger to the Christian faith. The second, developed by Eymerich from a selective reading of Aquinas’s writings, indicated specific circumstances in which alchemists could be investigated. The Roman Inquisition’s response to alchemy vacillated between the positions advocated by Aquinas and Eymerich. 相似文献
912.
913.
Neil D. Bowley Muriel Funck Dominic M. Laventine Scott J. Dalgarno 《Supramolecular chemistry》2014,26(3-4):229-232
A novel polar solvent-soluble tetra-functionalised cyano-footed calixarene forms a dimeric capsule, sealed via a hydrogen-bonding network between the two macrocycles, a single water molecule and a chloride anion, resulting in the encapsulation of a pyridinium guest, as shown in both solution and the solid state. 相似文献
914.
915.
Establishing the Coordination Chemistry of Antimony(V) Cations: Systematic Assessment of Ph4Sb(OTf) and Ph3Sb(OTf)2 as Lewis Acceptors
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Dr. Alasdair P. M. Robertson Saurabh S. Chitnis Dr. Hilary A. Jenkins Dr. Robert McDonald Dr. Michael J. Ferguson Prof. Neil Burford 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7902-7913
The coordination chemistry of the stiboranes Ph4Sb(OTf) ( 1 a , OTf = OSO2CF3) and Ph3Sb(OTf)2 ( 3 ) with Lewis bases has been investigated. The significant steric encumbrance of the Sb center in 1 a precludes interaction with most ligands, but the relatively low steric demands of 4‐methylpyridine‐N‐oxide (OPyrMe) and OPMe3 enabled the characterization of [Ph4Sb(OPyrMe)][OTf] ( 2 a ) and [Ph4Sb(OPMe3)][OTf] ( 2 b ), rare examples of structurally characterized complexes of stibonium acceptors. In contrast, 3 was found to engage a variety of Lewis bases, forming stable isolable complexes of the form [Ph3Sb(donor)2][OTf]2 [donor=OPMe3 ( 6 a ), OPCy3 ( 6 b , Cy=cyclohexyl), OPPh3 ( 6 c ), OPyrMe ( 6 d )], [Ph3Sb(dmap)2(OTf)][OTf] ( 6 e , dmap=4‐(dimethylamino)pyridine) and [Ph3Sb(donor)(OTf)][OTf] [donor=1,10‐phenanthroline ( 7 a ) or 2,2′‐bipy ( 7 b , bipy=bipyridine)]. These compounds exhibit significant structural diversity in the solid‐state, and undergo ligand exchange reactions in line with their assignment as coordination complexes. Compound 3 did not form stable complexes with phosphine donors, with reactions instead leading to redox processes yielding SbPh3 and products of phosphine oxidation. 相似文献
916.
Reaction of C5H4(SiMe3)2 with Mo(CO)6 yielded [(η5-C5H3(SiMe3)2)Mo(CO)3]2, which on addition of iodine gave [(η5-C5H3(SiMe3)2Mo(CO)3I]. Carbonyl displacement by a range of ligands: [L = P(OMe)3, P(OPri)3,P(O-o-tol)3, PMe3, PMe2Ph, PMePh2, PPh3, P(m-tol)3] gave the new complexes [(η5-C5H3(SiMe3)2 MO(CO)2(L)I]. For all the trans isomer was the dominant, if not exclusive, isomer formed in the reaction. An NOE spectral analysis of [(η5-C5H3(SiMe3)2)Mo(CO)2(L)I] L = PMe2Ph, P(OMe)3] revealed that the L group resided on the sterically uncongested side of the cyclopentadienyl ligand and that the ligand did not access the congested side of the molecule. Quantification of this phenomenon [L = P(OMe)3] was achieved by means of the vertex angle of overlap methodology. This methodology revealed a steric preference with the trans isomer (less congestion of CO than I with an SiMe3 group) being the more stable isomer for L = P(OMe)3. 相似文献
917.
918.
919.
Neil Hindman 《Journal of Combinatorial Theory, Series A》1982,33(2):147-157
The principal result is that if a question of Erdös about pairwise sums has a counterexample, then it has counterexamples with maximal density arbitrarily close to 1. In investigating this question, several results about translates of sets with positive-maximal density and with positive asymptotic-upper density are also derived. 相似文献
920.
Joy S. Finney Peter H. Bach Mary-Clare Bushell Neil M. Gregg David G. Taylor 《Magnetic resonance imaging》1990,8(6):713-721
Renal cortical and medullary spin-lattice (T1) relaxation times were measured at various time points over a period of 56 days following the administration of a single i.p. injection of 100 mg/kg 2-bromoethanamine hydrobromide (BEA), 200 mg/kg hexachloro-1,3-butadiene (HCBD) or 100 mg/kg puromycin aminonucleoside (PAN) to male Wistar rats. Administration of a single injection of HCBD caused a dramatic, immediate rise in the cortical T1 values above control values, and these levels remained elevated until, by Day 28 postinjection the levels were back to control values. Administration of BEA also caused an elevation in cortical T1 values, but in this case these values remained above control values for the rest of the study. The administration of PAN did not produce any significant increases in cortical T1 values until 14 days postinjection. The elevated T1 values remained above control values for the rest of the study. These increases observed in cortical T1 values appeared to be mirrored by decreases in medullary T1 values. Increases in cortical T1 values were accompanied by visual changes in the NMR images and enlargement of the kidneys. The histological findings were consistent with the NMR data, confirming that morphologically the tissues did show a full recovery by Day 28 in the HCBD-treated animals. This was not the case following injection of both BEA and PAN, where necrosis was not reversible and there was no recovery of the tissues. 相似文献