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Magnus Fröhling Frank Schwaderer Hauke Bartusch Otto Rentz 《European Journal of Operational Research》2010
By-products accrue in all stages of industrial production networks. Legal requirements, shortening of primary resources and their increasing prices make their recycling more and more important. For the re-integration into the economic cycle the scope of common supply chain management is enlarged and so-called closed-loop supply chains with adapted and new planning tasks are developed. In process industries this requires a detailed modelling of the recycling processes. This is of special relevance for operational planning tasks in which an optimal usage of a given production system is envisaged. This contribution presents an integrated planning approach for a real-world case study from the zinc industry to achieve such an adequate process modelling. We consider the planning problem of a company that operates four metallurgical recycling plants and has to allocate residues from different sources to these recycling sites. The allocation determines the raw material mix used in the plants. This blending has an effect on the transportation costs and the costs and revenues of the individual technical processes in the recycling plants. Therefore in this problem transportation and recycling planning for multiple sites have to be regarded in an integrated way. The necessary detailed process modelling is achieved by the use of a flowsheet process simulation system to model each recycling plant individually. The models are used to derive linear input–output functions by multiple linear regression analyses. These are used in an integrated planning model to calculate the decision-relevant input and output flows that are dependent upon the allocation of the residues to the recycling sites. The model is embedded in a decision support system for the operational use. An example application and sensitivity analyses demonstrate and validate the approach and its potentials. The approach is transferable to other recycling processes as well as to other processes in process industries. 相似文献
115.
Tao Wei Oliver Martin Shangfeng Yang Frank Hauke Andreas Hirsch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(3):826-830
Two novel graphene‐fullerene hybrid structures, containing C60 and endohedral Sc3N@C80 bound to graphene, instead of the formerly used graphene oxide, were efficiently synthesized via a reductive activation/exfoliation approach starting from pristine graphite. The structures of these multifunctional hybrid systems were unambiguously characterized by statistical Raman spectroscopy, TG‐MS, TG‐GC‐MS, and LD‐TOF mass spectroscopy, confirming the covalent bonding of the respective C60/Sc3N@C80 moieties to the pristine graphene. Furthermore, assisted by temperature‐dependent Raman spectroscopy studies the corresponding defunctionalization processes were also investigated. Finally, the formation of a carbon allotrope hybrid material on the basis of C60/Sc3N@C80 moieties coupled to graphene could be visualized by HRTEM. 相似文献
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Stefan Wild Michael Fickert Aleksandra Mitrovic Vicent Lloret Christian Neiss Jos Alejandro Vidal‐Moya Miguel ngel Rivero‐Crespo Antonio Leyva‐Prez Katharina Werbach Herwig Peterlik Mathias Grabau Haiko Wittkmper Christian Papp Hans‐Peter Steinrück Thomas Pichler Andreas Grling Frank Hauke Gonzalo Abelln Andreas Hirsch 《Angewandte Chemie (International ed. in English)》2019,58(17):5763-5768
The chemical bulk reductive covalent functionalization of thin‐layer black phosphorus (BP) using BP intercalation compounds has been developed. Through effective reductive activation, covalent functionalization of the charged BP by reaction with organic alkyl halides is achieved. Functionalization was extensively demonstrated by means of several spectroscopic techniques and DFT calculations; the products showed higher functionalization degrees than those obtained by neutral routes. 相似文献
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Hartmut Schulz Hauke Reddmann Hanns-Dieter Amberger 《Journal of organometallic chemistry》1992,430(3):317-325
The composition of (C6Me6)TiAl2Cl8−xEtx complexes in (C6Me6)TiAl2Cl8 + n Et3Al (n = 0.5-6) systems was studied by UV-Vis spectroscopy and the X-ray crystal structure of one of them, (η6-C6Me6)Ti[(μ-Cl)2(AlClEt)]2 (IIa-2), has been determined. The complex crystallizes in the orthorhombic space group Pna21 with Z = 4 and lattice parameters a 15.634(3), b 11.355(2), c 14.417(2) Å. The ethyl groups of IIa-2 reside in outer positions of aluminate ligands farther away from the C6Me6 ligand. The other part of the complex does not differ remarkably from structures of other (arene)TiII complexes. Negligible activity of (C6Me6)TiAl2Cl8 towards the butadiene cyclotrimerization is considerably increased by addition of 2.5–3.0 equivalents of Et3Al. As follows from UV-Vis spectra, such systems contain mainly the (C6Me6)TiAl2Cl5Et3 complex. It is suggested that the introduction of three Et substituents destabilizes the Ti-(η6-C6Me6) bond so that the replacement of hexamethylbenzene by butadiene in the first step of a catalytic cycle becomes more feasible. 相似文献
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Let x ~ N(μ, Z), and let S = (Σ:μ). It is shown that if x′A1x is independent of x′Bx (x′A1x is distributed as a chi-square variable), then this property is inherited by every x′A2x for which S′A2S precedes S′A1S with respect to the range preordering (with respect to the rank subtractivity partial ordering). 相似文献
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A time-domain approach for the simulation of elastic waves in heterogeneous soil domains is presented. It is based on modelling both near and far field by the scaled boundary finite element method (SBFEM). The SBFEM facilitates the use of a structured mesh in the near field region without the need to circumvent hanging nodes. The quadtree mesh is obtained automatically from image data. Radiation damping in the far field is modelled accurately by means of a displacement unit-impulse-response-based formulation. An example analysis of wave radiation by an alluvial basin illustrates the potential of the proposed methodology. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献