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81.
82.
Thomas Billot Rainer Beckert Manfred Dring Jrg Wuckelt Peer Fehling Helmar Grls 《Journal of heterocyclic chemistry》2001,38(1):205-211
The synthesis of pyrido[2,1‐c]‐1,2,4‐triazines 6 , pyrido[1,2‐b]‐1,2,4‐triazines 7 and pyrido[1,2‐b]pyri‐dazines 8 respectively by cycloacylation of derivatives of pyridine with imidoylchlorides of type 2 is described. The heterocycles of type 6 as well as of type 7 can be ring‐transformed with dimethyl acetylenedicarboxylate. In contrast to pyrido[1,2‐a]pyrazines 1, a complex reaction including cleavage of the acetylene subunit takes place. Starting from compound 6a , the pyrrolo[2,3‐d]imidazole 11a could be isolated from a mixture of unidentified by‐products, whereas derivatives 7 gave nearly quantitatively the tricyclic products of type 12 . 相似文献
83.
84.
Bau S Schracke N Kränzle M Wu H Stähler PF Hoheisel JD Beier M Summerer D 《Analytical and bioanalytical chemistry》2009,393(1):171-175
We report a flexible method for selective capture of sequence fragments from complex, eukaryotic genome libraries for next-generation
sequencing based on hybridization to DNA microarrays. Using microfluidic array architecture and integrated hardware, the process
is amenable to complete automation and does not introduce amplification steps into the standard library preparation workflow,
thereby avoiding bias of sequence distribution and fragment lengths. We captured a discontiguous human genomic target region
of 185 kb using a tiling design with 50mer probes. Analysis by high-throughput sequencing using an Illumina/Solexa 1G Genome
Analyzer revealed 2150-fold enrichment with mean per base coverage between 4.6 and 107.5-fold for the individual target regions.
This method represents a flexible and cost-effective approach for large-scale resequencing of complex genomes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Stephan Bau and Nadine Schracke contributed equally to this work. 相似文献
85.
Via sol–gel processing metal–organic fibers were produced and dried up to 140 °C. For these gel fibers the influence of a
treatment in different atmospheres was investigated for the temperature range of 200–850 °C. The atmospheres were nitrogen,
water vapor, evaporated nitric and hydrochloric acid and evaporated hydrogen peroxide. In the presence of moisture and especially
with acidic moisture fibers were transformed almost completely to their oxide composition (82 mol% Al2O3·18 mol% Y2O3). In these inorganic amorphous structures considerable differences were observed on several structural levels. On the atomic
scale, the coordination of Al ions was investigated by 27Al MAS NMR and skeletal density by He-pycnometry. Porosity in the nm scale was characterized by N2-sorption. As a macroscopic effect of different treatment atmospheres, the longitudinal shrinkage was observed. For fibers
treated at 500 °C the relative shrinkage varied by 100% (comparing water vapor and nitrogen atmosphere). No simple correlation
between the release of organic constituents, the formation of porosity and the shrinkage could be found. These aspects were
controlled by the rigidity of the inorganic network against atomic reconstitution. The kind of atmosphere was found to be
an effective parameter to control various aspects of the xerogel structure. 相似文献
86.
87.
We show that, for negative generators of analytic semigroups, a bounded ‐calculus self‐improves to an ‐bounded ‐calculus in an appropriate scale of ‐spaces if the semigroup satisfies suitable generalized Gaussian estimates. As application of our result we obtain that large classes of differential operators have an ‐bounded ‐calculus. 相似文献
88.
Federica Mancini Dr. M. Yagiz Unver Dr. Walid A. M. Elgaher Dr. Varsha R. Jumde Alaa Alhayek Dr. Peer Lukat Dr. Jennifer Herrmann Dr. Martin D. Witte Dr. Matthias Köck Prof. Dr. Wulf Blankenfeldt Prof. Dr. Rolf Müller Prof. Dr. Anna K. H. Hirsch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(64):14585-14593
Kinetic target-guided synthesis represents an efficient hit-identification strategy, in which the protein assembles its own inhibitors from a pool of complementary building blocks via an irreversible reaction. Herein, we pioneered an in situ Ugi reaction for the identification of novel inhibitors of a model enzyme and binders for an important drug target, namely, the aspartic protease endothiapepsin and the bacterial β-sliding clamp DnaN, respectively. Highly sensitive mass-spectrometry methods enabled monitoring of the protein-templated reaction of four complementary reaction partners, which occurred in a background-free manner for endothiapepsin or with a clear amplification of two binders in the presence of DnaN. The Ugi products we identified show low micromolar activity on endothiapepsin or moderate affinity for the β-sliding clamp. We succeeded in expanding the portfolio of chemical reactions and biological targets and demonstrated the efficiency and sensitivity of this approach, which can find application on any drug target. 相似文献
89.
Falk Pabst Jen-Hui Chang Kati Finzel Miroslav Kohout Peer Schmidt Michael Ruck 《无机化学与普通化学杂志》2020,646(3):149-155
Black and irregularly shaped crystals of the bismuth-rich bromide Bi5Br4 were obtained as a by-product of the reaction of CsBr, Bi, and BiBr3. X-ray diffraction on a single-crystal revealed its orthorhombic structure with the space group Pmmn (no. 59) and lattice parameters a = 1800.0(2) pm, b = 1476.1(1) pm, and c = 924.5(2) pm at 296 K. The structure is composed of Bi82+ and Bi95+ polycations and bromidobismuthate(III) anions according to the structured formula Bi5Br4 = Bi20Br16 = Bi82+Bi95+[BiBr5]2–[Bi2Br11]5–. Bi5Br4 is the bismuth-richest among the bismuth subhalides containing isolated polycations. Extensive differential scanning calorimetry studies indicate that Bi5Br4 decomposes at 262 °C, i.e. one degree below the bismuth-rich eutectic at 263 °C. All attempts towards a rational synthesis yielded predominantly the neighboring phases BiBr and Bi6Br7. 相似文献
90.
C. Rathika Thaya Kumari P. Jayaprakash M. Nageshwari M. Peer Mohamed P. Sangeetha 《Molecular Crystals and Liquid Crystals》2017,658(1):186-197
A nonlinear optical material benzoyl valine (BV) was synthesized by the technique of slow evaporation process at room temperature. The single crystal X ray diffraction analysis evince that crystal corresponds to acentric space group P21 with monoclinic system. The diverse optical properties assured an elevated transparency in BV crystal. Photoluminescence profile revealed the suitability of crystal for fabricating violet lasers. The Laser damage threshold and the dielectric behavior of the grown crystal were analyzed to indicate its practical applications. The second and third order nonlinear optical measurements were studied to prove its potentiality in the domain of nonlinear optical applications. 相似文献