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61.
Conventional integral-imaging systems utilize lenslet arrays with fixed focal lengths and aperture sizes. We propose a time-multiplexed integral-imaging method that enhances both the depth of focus and the resolution of a three-dimensional image by displaying it with an array of lenslets with different focal lengths and aperture sizes. The nonuniform lenslet parameters (focal lengths and aperture sizes) for our method are calculated. Our theoretical analysis indicates that significant improvements in both depth of focus and resolution can be obtained with the proposed technique. 相似文献
62.
Three-dimensional-object recognition by use of single-exposure on-axis digital holography 总被引:6,自引:0,他引:6
On-axis phase-shifting digital holography requires recording of multiple holograms. We describe a novel real-time three-dimensional- (3-D-) object recognition system that uses single-exposure on-axis digital holography. In contrast to 3-D-object recognition by means of a conventional phase-shifting scheme that requires multiple exposures, our proposed method requires only a single digital hologram to be synthesized and used to recognize 3-D objects. A benefit of the proposed 3-D recognition method is enhanced practicality of digital holography for 3-D recognition in terms of its simplicity and greater robustness to external scene parameters such as moving targets and environmental noise factors. We show experimentally the utility of the single-exposure on-axis digital holography-based 3-D-object recognition method. 相似文献
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64.
Improved viewing resolution of three-dimensional integral imaging by use of nonstationary micro-optics 总被引:4,自引:0,他引:4
We propose the use of synchronously moving micro-optics (lenslet arrays) for image pickup and display in three-dimensional integral imaging to overcome the upper resolution limit imposed by the Nyquist sampling theorem. With the proposed technique, we show experimentally that the viewing resolution can be improved without reducing the three-dimensional viewing aspect of the reconstructed image. 相似文献
65.
Mojtaba Mahyari Seyyed Emad Hooshmand Heshmatollah Sepahvand Jaber Nasrollah Gavgani Seyed Ghorban Hosseini 《应用有机金属化学》2020,34(4):e5540
Biomimetic complexes such as porphyrins, phthalocyanines, and hemins show promising catalytic activities in redox processes. Donor-acceptor hybrids of these biomimetic macrocyclic complexes with graphene as one of the most critical allotropes of carbon are currently an outstanding scientific frontier. Notably, the composites that consist of these efficient and bio-inspiring complexes anchored on the surface of the graphene and their widespread applications have gained ever-increasing interest in the last decade, which expresses their efficiency in practice. Accordingly, this review covers the current status of biomimetic complexes-graphene composites with particular emphasis on significant signs of their synthesis and characterization also highlighted applications of these composites in academia and industrial redox processes such as oxidation of organic compounds, epoxidation, oxygen reduction reactions, CO2 reduction, and hydrogen evolution reactions. 相似文献
66.
Thermal Behavior of d‐Ribose Adsorbed on Silica: Effect of Inorganic Salt Coadsorption and Significance for Prebiotic Chemistry 下载免费PDF全文
Mariame Akouche Maguy Jaber Emilie‐Laure Zins Marie‐Christine Maurel Jean‐Francois Lambert Thomas Georgelin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15834-15846
Understanding ribose reactivity is a crucial step in the “RNA world” scenario because this molecule is a component of all extant nucleotides that make up RNA. In solution, ribose is unstable and susceptible to thermal destruction. We examined how ribose behaves upon thermal activation when adsorbed on silica, either alone or with the coadsorption of inorganic salts (MgCl2, CaCl2, SrCl2, CuCl2, FeCl2, FeCl3, ZnCl2). A combination of 13C NMR, in situ IR, and TGA analyses revealed a variety of phenomena. When adsorbed alone, ribose remains stable up to 150 °C, at which point ring opening is observed, together with minor oxidation to a lactone. All the metal salts studied showed specific interactions with ribose after dehydration, resulting in the formation of polydentate metal ion complexes. Anomeric equilibria were affected, generally favoring ribofuranoses. Zn2+ stabilized ribose up to higher temperatures than bare silica (180 to 200 °C). Most other cations had an adverse effect on ribose stability, with ring opening already upon drying at 70 °C. In addition, alkaline earth cations catalyzed the dehydration of ribose to furfural and, to variable degrees, its further decarbonylation to furan. Transition‐metal ions with open d‐shells took part in redox reactions with ribose, either as reagents or as catalysts. These results allow the likelihood of prebiotic chemistry scenarios to be evaluated, and may also be of interest for the valorization of biomass‐derived carbohydrates by heterogeneous catalysis. 相似文献
67.
Shuai Liu Yujie Wu Teng Lin Robert Abel Jonathan P. Redmann Christopher M. Summa Vivian R. Jaber Nathan M. Lim David L. Mobley 《Journal of computer-aided molecular design》2013,27(9):755-770
Alchemical free energy calculations hold increasing promise as an aid to drug discovery efforts. However, applications of these techniques in discovery projects have been relatively few, partly because of the difficulty of planning and setting up calculations. Here, we introduce lead optimization mapper, LOMAP, an automated algorithm to plan efficient relative free energy calculations between potential ligands within a substantial library of perhaps hundreds of compounds. In this approach, ligands are first grouped by structural similarity primarily based on the size of a (loosely defined) maximal common substructure, and then calculations are planned within and between sets of structurally related compounds. An emphasis is placed on ensuring that relative free energies can be obtained between any pair of compounds without combining the results of too many different relative free energy calculations (to avoid accumulation of error) and by providing some redundancy to allow for the possibility of error and consistency checking and provide some insight into when results can be expected to be unreliable. The algorithm is discussed in detail and a Python implementation, based on both Schrödinger’s and OpenEye’s APIs, has been made available freely under the BSD license. 相似文献
68.
Computational Management Science - Wright’s learning curve (WLC) assumes every unit of production has an acceptable level of quality, which is not the case in many production environments.... 相似文献
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70.
Consanguineous marriages have been practiced for hundreds of years in many parts of the world. The rate of congenital malformations among the offspring is 2.5 times higher than that among the offspring of unrelated parents, mainly due to the expression of autosomal-recessive disorders, and hospitalization for these reasons causes a major financial burden. An increase in sterility and in the rates of abortion, stillbirths, perinatal losses and neonatal deaths has been reported by some authors but not by others. It is generally accepted that the advantages of consanguinity outweigh the disadvantages; however, strategies for reducing the burden require a unique approach as discussed in this article. 相似文献