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321.
Jolanta Kowalska Agata Marzec Ewa Domian Sabina Galus Agnieszka Ciurzyska Andrzej Lenart Hanna Kowalska 《Molecules (Basel, Switzerland)》2020,25(23)
The visible trend in the development of the snack market focuses on the use of innovative technologies such as low-temperature or hybrid processes that allow the preservation of native ingredients of raw plant materials. In addition, the high antioxidant potential of, for example, chokeberry fruit can be used to support technological processes and create new products. The aim of the study was to evaluate the possibility of using chokeberry juice concentrate as a component of an osmotic solution to enrich apple samples with natural bio-ingredients and obtain dried apples with increased content of ingredients with antioxidant properties; pro-healthy apple chips. The research material consisted of apples that underwent osmotic dehydration in solutions of sucrose or sucrose and chokeberry juice concentrate and then were dried by the freeze-drying or the hybrid method. The freeze-drying was more beneficial for maintaining the vitamin C content, while the use of the hybrid method resulted in the preservation of more polyphenolic compounds. The sensory evaluation indicated the need to modify the composition of the osmoactive solution. Due to the use of chokeberry juice concentrate, the content of vitamin C, polyphenols, and the antioxidant activity of dried apples was increased. 相似文献
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324.
This study demonstrates pattern generation on a highly durable and flat diamond-like-carbon (DLC) film with micro/nano-scale resolution using the Atomic Force Microscope (AFM). Parallel processing (masked lithography) and serial local probe processing (maskless lithography) have both been utilized to produce a range of structure shapes at different length scales. The AFM is operated in the electrical conductivity mode which induces oxidation on the DLC surface. The technique offers features with structure depths as small as 20 nm (serial processing) and pattern replication of many centimeters (parallel processing). Moreover parallel processed structures may be further modified via serial patterning using the same instrumentation. As a result, complex shapes can be produced with a depth being controlled by the DLC film thickness and/or by the bias voltage parameters. The patterned DLC structures can be used as a template for fabrication of 3 dimensional polymeric structures. 相似文献
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326.
Dr. Kirsten Schwing Dr. Holger Fricke Dr. Kristina Bartl Dr. Jolanta Polkowska Prof. Dr. Thomas Schrader Prof. Dr. Markus Gerhards 《Chemphyschem》2012,13(6):1576-1582
The functionality of bioactive molecules sensitively depends on their structure. For the investigation of intrinsic structural properties, molecular beam experiments combined with laser spectroscopy have proven to be a suitable tool. Herein we present an analysis of the two isolated tripeptide model systems Ac‐Phe‐Tyr(Me)‐NHMe and Boc‐Phe‐Tyr(Me)‐NHMe. For this purpose, mass‐selective combined IR/UV spectroscopy is applied to both substances in a molecular beam experiment. The comparison of the experimental data with DFT calculations, including different functionals as well as dispersion corrections, allows an assignment of both tripeptide models to β‐turns formed independently from the protection groups and supported by the interaction of the two aromatic chromophores. 相似文献
327.
This paper recalls some properties of a cyclic semigroup and examines cyclic subsemigroups in a finite ordered semigroup. We prove that a partially ordered cyclic semigroup has a spiral structure which leads to a separation of three classes of such semigroups. The cardinality of the order relation is also estimated. Some results concern semigroups with a lattice order. 相似文献
328.
Yurii S. Moroz El
bieta Gumienna‐Kontecka Igor O. Fritsky Nikolay M. Dudarenko Jolanta
witek‐Kozowska 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):m498-m500
The title compound, (C2H10N2)2[Ni(C2HN2O4)2]·2H2O, has an ionic structure containing a centrosymmetric complex 4− anion, charge‐balancing ethylenediaminium dications and solvent water molecules. The oxalohydroxamate unit is triply deprotonated and forms five‐membered chelate rings with the central Ni ion; the Ni ion lies on an inversion centre. The two hydroxamate O atoms in the complex anion are linked by short intramolecular hydrogen bonds. 相似文献
329.
Type II ceramides were separated according to the length of their fatty acid alkyl chain using two column system. The packing of the first column was non-polar adsorbent prepared by coating of macroporous spherical silica with cationized poly(vinyl alcohol) of low substitution degree. Commercial normal phase column Lichrosorb Si 60 was used as a second column in this system. Elution was performed in an isocratic mode using methanol:chloroform 50:50 (v/v) as an eluent.
相似文献330.
Jolanta Prywer 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,25(1):61-68
According to contemporary crystal growth theories, crystals are bound by low-index faces which are the most slowly growing.
However, high-index faces are observed in crystal habits more and more often. In this paper the growth of high-index faces
is analysed from a crystallographic perspective. It is shown that the crystallographic structure of a given crystal, expressed
by the trigonometric function of appropriate interfacial angles, influences to great degree the crystallisation process and
the morphology of crystals, in particular the behaviour of high-index faces. Additionally, it is concluded that at particular
crystallographic structure of a crystal, a given high-index face may exist in the habit and develop its size, although it
grows much faster than the neighbouring faces.
Received 31 July 2001 相似文献