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21.
Kirralee J. Burke Dr. Liam J. Stephens Dr. Melissa V. Werrett Prof. Philip C. Andrews 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(34):7657-7671
A series of homoleptic and heteroleptic bismuth(III) flavonolate complexes derived from six flavonols of varying substitution have been synthesised and structurally characterised. The complexes were evaluated for antibacterial activity towards several problematic Gram-positive (Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE)) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. The cell viability of COS-7 (monkey kidney) cells treated with the bismuth flavonolates was also studied to determine the effect of the complexes on mammalian cells. The heteroleptic complexes [BiPh(L)2] (in which L=flavonolate) showed good antibacterial activity towards all of the bacteria but reduced COS-7 cell viability in a concentration-dependent manner. The homoleptic complexes [Bi(L)3] exhibited activity towards the Gram-positive bacteria and showed low toxicity towards the mammalian cell line. Bismuth uptake studies in VRE and COS-7 cells treated with the bismuth flavonolate complexes indicated that Bi accumulation is influenced by both the substitution of the flavonolate ligands and the degree of substitution at the bismuth centre. 相似文献
22.
Liam J. R. McGeachie Cameron L. Carpenter-Warren David B. Cordes Michael Bühl Steven J. Gray Guoxiong Hua Alexandra M. Z. Slawin J. Derek Woollins 《无机化学与普通化学杂志》2020,646(22):1795-1798
An improved route to d-block and main group NSO complexes is presented including the synthesis of the first antimony(V) complexes, (Ar3Sb(NSO)2), and copper examples [CuBipy(PPh3)NSO]. The structures of eight complexes are reported. The observed variation in M–N–S bond angles is due to the combination of orbital overlap (ligand-to-metal bonding) and the degree of ionicity of the bonding. 相似文献
23.
A Carbene‐Rich but Carbonyl‐Poor [Ir6(IMe)8(CO)2H14]2+ Polyhydride Cluster as a Deactivation Product from Catalytic Glycerol Dehydrogenation 下载免费PDF全文
Jesús Campos Liam S. Sharninghausen Prof. Robert H. Crabtree Dr. David Balcells 《Angewandte Chemie (International ed. in English)》2014,53(47):12808-12811
The title cluster, a deactivation product in the catalytic dehydrogenation of glycerol, was characterized by XRD, DFT calculations, HRMS, FTIR spectroscopy, and NMR spectroscopy. Experimental/computational studies located the 14 H ligands, and all 1H and 13C{1H} NMR resonances were assigned. The structure contains an unprecedented Ir6H14 core with two CO and eight IMe ligands. 相似文献
24.
Spencer LP Gdula RL Hayton TW Scott BL Boncella JM 《Chemical communications (Cambridge, England)》2008,(40):4986-4988
The bis(imido) uranium(VI)-C(5)H(5) and -C(5)Me(5) complexes (C(5)H(5))(2)U(N(t)Bu)(2), (C(5)Me(5))(2)U(N(t)Bu)(2), (C(5)H(5))U(N(t)Bu)(2)(I)(dmpe), and (C(5)H(5))(2)U(N(t)Bu)(2)(dmpe) can be synthesized from reactions between U(N(t)Bu)(2)(I)(2)(L)(x) (L=THF, x=2; L=dmpe, x=1) and Na(C(5)R(5)) (R=H, Me); these complexes represent the first structurally characterized C(5)H(5)-compounds of uranium(VI) and they further highlight the differences between UO(2)(2+) and the bis(imido) fragment. 相似文献
25.
The formation of 2,3-disubstituted thiazolidin-4-ones from s-α'-aminomercaptoacetic acid derivatives
John Tierney 《Journal of heterocyclic chemistry》1989,26(4):997-1001
Variously substituted N-benzylidineanilines rapidly react with thioglycolic acid to generate S-α'-aminomercaptoacetic acid derivatives. The latter subsequently cyclize to the corresponding 2,3-diarylthiazolidin-4-ones. Kinetics for the first order cyclization reaction in the solvents toluene, carbon tetrachloride and nitrobenzene have been obtained over the temperature range 333 K to 383 K and are in accord with a neutral, but geometrically complex transition state. 相似文献
26.
Liam Evans John Hedger Brian W. Skelton R. Thomas Williamson 《Tetrahedron letters》2010,51(41):5493-5496
Three new unusual sesquiterpenes (1-3) were isolated from the tropical rainforest basidiomycete, Marasmiellus troyanus and their structure elucidation was achieved by NMR spectroscopy, single-crystal X-ray structural analysis and a modified Mosher’s ester method to determine the absolute stereochemistry of compound 1. These unusual metabolites are probably derived from the caryophyllane class of sesquiterpenes and a possible biosynthetic route to these compounds is proposed. These small natural products represent the best possible features of chemical diversity, being chiral and exhibiting extensive functional group chemistry highlighting the value of natural products as a screening resource for therapeutics discovery programmes. 相似文献
27.
Stefan Hubert Liam Pettigrew Thorben Helmers Ulrich Mießner Frauke Groß Norbert Räbiger Antonio Delgado 《PAMM》2014,14(1):811-812
This study introduces the concept of computer modelling and simulation of complex bioprocesses and systems using an approach that combines the reference net formalism with machine learning and optimisation techniques. Reference nets are an extension of high level Petri Nets, which can be used as a central visualisation and modelling tool. The net-in-net paradigm used by reference nets makes it possible to model complex processes, such as those found in the food and beverage industry. A plugin/interface system based on the java programming language allows implementation of advanced mathematical modelling techniques at specific points in entire system simulations. Separate optimisation tools can also run and modify existing reference net models for fast solutions to efficiency problems. We present an example system that simulates a specific section of a beer brewery using the reference net formalism, which is optimised using a genetic algorithm. We show in detail how the different software packages can be combined for a simulation based optimisation approach. The optimisation technique specifically addresses the wastewater pollution load in regard to its chemical oxygen demand. A beer brewery was chosen as an example for this study due to the constantly increasing requirements to lower energy and water consumption in this industry. One possibility to lower the energy and water demands is to effectively treat wastewater produced by the brewery, which can introduce cost savings by providing recycled water and biogas. Most approaches to wastewater treatment are end-of-pipe solutions that do not consider the brewery as a whole. A brewery contains many processes that can be running concurrently and interacting with one another (e.g. brewing, clean-in-place and bottling) with each process producing varying amounts of wastewater with different pollution loads. Optimisation of the scheduling of the different processes with respect to the wastewater production will allow for more effective wastewater treatment, and therefore cost and energy savings. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
28.
Ben W. Joynson Dr. Graham R. Cumming Dr. Liam T. Ball 《Angewandte Chemie (International ed. in English)》2023,62(31):e202305081
We demonstrate that arylchlorodiazirines serve as photo-activated halocarbene precursors for the selective one-carbon ring expansion of N-substituted pyrroles and indoles to the corresponding pyridinium and quinolinium salts. Preliminary investigations indicate that the same strategy also enables the conversion of N-substituted pyrazoles to pyrimidinium salts. The N-substituent of the substrate plays an essential role in: (1) increasing substrate scope by preventing product degradation, (2) enhancing yields by suppressing co-product inhibition, and (3) activating the azinium products towards subsequent synthetic manipulations. This latter point is illustrated by subjecting the quinolinium salts to four complementary partial reductions, which provide concise access to ring-expanded products with different degrees of increased C(sp3) character. Thermal analysis of the diazirines by differential scanning calorimetry (DSC) provides detailed insight into their energetic properties, and highlights the safety benefits of photolyzing—rather than thermolyzing—these reagents. 相似文献
29.
Donald Craig V. Ranjit N. Munasinghe Jason P. Tierney Andrew J. P. White David J. Williams Christopher Williamson 《Tetrahedron》1999,55(52):2315-15044
Bicyclic ketooxetanes may be assembled using cation-mediated cyclisation reactions of thioglycosides possessing silyl enol ether-containing side-chains. 相似文献
30.
We report the synthesis and structural characterisation of three five co-ordinate indium(III) bis-chelate complexes of imidodiphosphinates with general formula InCl{N(PR2X)2}2, (R=Ph or Pri, X=S or Se), formed from the 1:2 reaction of indium(III) trichloride and the potassium or sodium salt of the ligand in methanol/THF. The complexes consist of discrete monomeric, molecules and show a trigonal–bipyramidal co-ordination pattern. These are the first examples of five co-ordinate complexes containing this type of ligand, in contrast to other indium(III) and main group element complexes of similar ligands in which only the six co-ordinate tris-chelates are known. 相似文献