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1.
2.
Ein elektronenreiches cyclisches (Alkyl)(amino)carben auf Au(111)-, Ag(111)- und Cu(111)-Oberflächen
Anne Bakker Dr. Matthias Freitag Elena Kolodzeiski Peter Bellotti Dr. Alexander Timmer Dr. Jindong Ren Bertram Schulze Lammers Daniel Moock Prof. Dr. Herbert W. Roesky Dr. Harry Mönig Dr. Saeed Amirjalayer Prof. Dr. Harald Fuchs Prof. Dr. Frank Glorius 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13745-13749
3.
Dr. Debabrata Maity Dr. Khaleel I. Assaf Wilhelm Sicking Dr. Christoph Hirschhäuser Prof. Dr. Werner M. Nau Prof. Dr. Carsten Schmuck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(57):13088-13093
A convenient supramolecular strategy for constructing a ratiometric fluorescent chemosensing ensemble, consisting of a macrocyclic host (cucurbit[8]uril CB[8]), and a pyrene-tagged amphiphilic peptide beacon (AP 1), is reported. AP 1 unfolds upon encapsulation of the pyrene termini into the hydrophobic CB[8] cavity. This changes pyrene excimer to monomer emission. Substrates with higher affinity for the CB[8] cavity can displace AP 1 from the ensemble. The released AP 1 folds again to form a pyrene excimer, which allows for the ratiometric fluorescence monitoring of the substrate. In this report, the ensemble capacity for ratiometric fluorescence monitoring of biological substrates, such as amino acid derivatives, specific peptides, and proteins, in aqueous media is demonstrated. 相似文献
4.
Theo Steininger Jait Dixit Philipp Frank Maksim Greiner Sebastian Hutschenreuter Jakob Knollmüller Reimar Leike Natalia Porqueres Daniel Pumpe Martin Reinecke Matev raml Csongor Varady Torsten Enßlin 《Annalen der Physik》2019,531(3)
NIFTy , “Numerical Information Field Theory,” is a software framework designed to ease the development and implementation of field inference algorithms. Field equations are formulated independently of the underlying spatial geometry allowing the user to focus on the algorithmic design. Under the hood, NIFTy ensures that the discretization of the implemented equations is consistent. This enables the user to prototype an algorithm rapidly in 1D and then apply it to high‐dimensional real‐world problems. This paper introduces NIFTy 3, a major upgrade to the original NIFTy framework. NIFTy 3 allows the user to run inference algorithms on massively parallel high performance computing clusters without changing the implementation of the field equations. It supports n‐dimensional Cartesian spaces, spherical spaces, power spaces, and product spaces as well as transforms to their harmonic counterparts. Furthermore, NIFTy 3 is able to handle non‐scalar fields, such as vector or tensor fields. The functionality and performance of the software package is demonstrated with example code, which implements a mock inference inspired by a real‐world algorithm from the realm of information field theory. NIFTy 3 is open‐source software available under the GNU General Public License v3 (GPL‐3) at https://gitlab.mpcdf.mpg.de/ift/NIFTy/tree/NIFTy_3 . 相似文献
5.
Xing Huang Detre Teschner Maria Dimitrakopoulou Alexey Fedorov Benjamin Frank Ralph Kraehnert Frank Rosowski Harry Kaiser Stephan Schunk Christiane Kuretschka Robert Schlgl Marc‐Georg Willinger Annette Trunschke 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(26):8801-8805
The direct conversion of syngas to ethanol, typically using promoted Rh catalysts, is a cornerstone reaction in CO2 utilization and hydrogen storage technologies. A rational catalyst development requires a detailed structural understanding of the activated catalyst and the role of promoters in driving chemoselectivity. Herein, we report a comprehensive atomic‐scale study of metal–promoter interactions in silica‐supported Rh, Rh–Mn, and Rh–Mn–Fe catalysts by aberration‐corrected (AC) TEM. While the catalytic reaction leads to the formation of a Rh carbide phase in the Rh–Mn/SiO2 catalyst, the addition of Fe results in the formation of bimetallic Rh–Fe alloys, which further improves the selectivity and prevents the carbide formation. In all promoted catalysts, Mn is present as an oxide decorating the metal particles. Based on the atomic insight obtained, structural and electronic modifications induced by promoters are revealed and a basis for refined theoretical models is provided. 相似文献
6.
Queueing Systems - In this paper, we use importance sampling simulation to estimate the probability that the number of customers in a d-node GI|GI|1 tandem queue reaches some high level N in a busy... 相似文献
7.
Anna Nme
kov‐Makrlíkov Frank‐Michael Matysik Tom Navrtil Jií Barek Vlastimil Vysko
il 《Electroanalysis》2019,31(2):303-308
Flow injection analysis with amperometric detection (FIA‐AD) at screen‐printed carbon electrodes (SPCEs) in optimum medium of Britton‐Robinson buffer (0.04 mol ? L?1, pH 2.0) was used for the determination of three tumor biomarkers (homovanillic acid (HVA), vanillylmandelic acid (VMA), and 5‐hydroxyindole‐3‐acetic acid (5‐HIAA)). Dependences of the peak current on the concentration of biomarkers were linear in the whole tested concentration range from 0.05 to 100 μmol ? L?1, with limits of detection (LODs) of 0.065 μmol ? L?1 for HVA, 0.053 μmol ? L?1 for VMA, and 0.033 μmol ? L?1 for 5‐HIAA (calculated from peak heights), and 0.024 μmol ? L?1 for HVA, 0.020 μmol ? L?1 for VMA, and 0.012 μmol ? L?1 for 5‐HIAA (calculated from peak areas), respectively. 相似文献
8.
The extraction of stoichiometric ternary K/Si/P, K/Ge/P, and K/Si/As solid mixtures with en/crypt‐222 afforded compounds with binary anions of the respective groups 14/15 elemental combination. Although the analysis of the products turned out to be extremely difficult owing to their intrinsically poor crystallinity and low solubility, we have evidence that one of them contains (SiP6H2)2– anions. Preliminary data from the two other compounds indicate the existence of the heavier Ge/P and Si/As variants as well. The combination of all analytical results, including X‐ray crystallography, energy‐dispersive X‐ray (EDX) spectroscopy, electrospray ionization mass spectrometry (ESI‐MS), and nuclear magnetic resonance (NMR) spectroscopy, point towards the named composition of the anions and their doubly protonated nature. By this, they represent the first binary Zintl anions of the Si/P and Si/As elemental combination and complement the recent endeavors to synthesize binary Zintl anions of the light(er) p‐block elements. We discuss our attempts to elucidate the clusters' identity and provide our results as the most probable interpretation of the data, additionally corroborated by quantum chemical analyses. 相似文献
9.
Four bis(dioxane) adducts of mixed‐metal trifluoroacetates, M[M′(O2CCF3)4(C4H8O2)2] (M = Na, K, Cs, M′ = In and M = Cs, M′ = Ga) were synthesized by reaction of alkali metal trifluoroacetate and group 13 element trifluoroacetate in 1,4‐dioxane and completely characterized including X‐ray structure determination. Geometric parameters, empirical bond valences and frequencies of the symmetric C=O stretching vibrations show that the moisture sensitive solids are composed of dimeric structural moieties with site symmetry 1 , containing alkali metal ions and bis(dioxane)tetrakis(trifluoroacetato)indate or ‐gallate ions. The dimeric units are further connected by weaker “intermolecular” dioxane interactions to neighboring alkali metal ions. Closer inspection of space group symmetry, unit cell parameters and atom sites allows to rationalize the compounds as members of two isotypic pairs that are further closely related due to the group‐subgroup relation of their monoclinc space groups to a common orthorhombic supergroup. 相似文献
10.
Phil Liebing Nicole Harmgarth Volker Lorenz Florian Zrner Liane Hilfert Sabine Busse Frank T. Edelmann 《无机化学与普通化学杂志》2019,645(4):440-446
A series of potentially useful lithium amidinates and guanidinates were prepared and fully characterized. Treatment of N,N′‐diisopropylcarbodiimide with phenyllithium in diethyl ether afforded the lithium amidinate [PhC(NiPr)2Li(OEt2)]2 ( 1 ). Similar treatment of N,N′‐diorganocarbodiimides R′–N=C=N–R′ [R′ = iPr, cyclohexyl (Cy)] with secondary lithium amides LiNR2 [R2 = Et2, iPr2, (CH2)4] followed by crystallization from THF or 1,4‐dioxane gave the lithium guanidinates [R2NC(NR′)2Li(S)]2 [ 2 : R = Et, R′ = iPr, S = THF; 3 : R2 = (CH2)4, R′ = iPr, S = THF; 4 : R = R′ = iPr, S = ½ 1,4‐dioxane; 5 : R2 = (CH2)4, R′ = Cy, S = 1,4‐dioxane] as crystalline solids. Reaction of N‐lithioaziridine with the corresponding carbodiimides afforded solvent‐deficient [{C2H4NC(NiPr2)2}2Li2(THF)]2 ( 6 ), and [C2H4NC(NEt)(NtBu)Li(THF)]2 ( 7 ). Crystal structure determination revealed the presence of common ladder‐type dimeric structures for 1 – 5 . Compound 6 exists as a dimer of two ladder‐type dimers in the crystal, and 7 exhibits an unusual dimeric structure comprising an eight‐membered C2N4Li2 ring. 相似文献