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81.
Florian Grimm Jasmin Rehman Dr. Stefan Stoldt Dr. Taukeer A. Khan Dr. Jan Gero Schlötel Dr. Shamil Nizamov Dr. Michael John Dr. Vladimir N. Belov Prof. Dr. Stefan W. Hell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(19):6070-6076
Formylation of 2,6-dichloro-5-R-nicotinic acids at C-4 followed by condensation with 3-hydroxy-N,N-dimethylaniline gave analogs of the popular TAMRA fluorescent dye with a 2,6-dichloro-5-R-nicotinic acid residues (R=H, F). The following reaction with thioglycolic acid is selective, involves only one chlorine atom at the carbon between pyridine nitrogen and the carboxylic acid group and affords new rhodamine dyes absorbing at 564/ 573 nm and emitting at 584/ 597 nm (R=H/ F, in aq. PBS). Conjugates of the dyes with “small molecules” provided specific labeling (covalent and non-covalent) of organelles as well as of components of the cytoskeleton in living cells and were combined with fluorescent probes prepared from 610CP and SiR dyes and applied in two-color STED microscopy with a 775 nm STED laser. 相似文献
82.
Jasmin Raissy 《Journal of Geometric Analysis》2010,20(2):472-524
Let f be a germ of biholomorphism of ℂ
n
, fixing the origin. We show that if the germ commutes with a torus action, then we get information on the germs that can
be conjugated to f, and furthermore on the existence of a holomorphic linearization or of a holomorphic normalization of f. We find out in a complete and computable manner what kind of structure a torus action must have in order to get a Poincaré-Dulac
holomorphic normalization, studying the possible torsion phenomena. In particular, we link the eigenvalues of df
O
to the weight matrix of the action. The link and the structure we found are more complicated than what one would expect;
a detailed study was needed to completely understand the relations between torus actions, holomorphic Poincaré-Dulac normalizations,
and torsion phenomena. We end the article giving an example of techniques that can be used to construct torus actions. 相似文献
83.
84.
Jie Jian Dr. Roel Hammink Prof. Dr. Christine J. McKenzie Prof. Dr. F. Matthias Bickelhaupt Prof. Dr. Jordi Poater Prof. Dr. Jasmin Mecinović 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(9):e202104044
Boronic acids are Lewis acids that exist in equilibrium with boronate forms in aqueous solution. Here we experimentally and computationally investigated the Lewis acidity of 2,6-diarylphenylboronic acids; specially designed phenylboronic acids that possess two flanking aromatic rings with tunable aromatic character. Hammett analysis of 2,6-diarylphenylboronic acids reveals that their Lewis acidity remains unchanged upon the introduction of EWG/EDG at the distant para position of the flanking aromatic rings. Structural and computational studies demonstrate that polar-π interactions and solvation effects contribute to the stabilization of boronic acids and boronate forms by aromatic rings. Our physical-organic chemistry work highlights that boronic acids and boronates can be stabilized by aromatic systems, leading to an important molecular knowledge for rational design and development of boronic acid-based catalysts and inhibitors of biomedically important proteins. 相似文献
85.
Pit Boden Patrick Di Martino-Fumo Jasmin M. Busch Florian R. Rehak Sophie Steiger Dr. Olaf Fuhr Dr. Martin Nieger Daniel Volz Prof. Willem Klopper Prof. Stefan Bräse Prof. Markus Gerhards 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(17):5439-5452
To develop new and flexible CuI containing luminescent substances, we extend our previous investigations on two metal-centered species to four metal-centered complexes. These complexes could be a basis for designing new organic light-emitting diode (OLED) relevant species. Both the synthesis and in-depth spectroscopic analysis, combined with high-level theoretical calculations are presented on a series of tetranuclear CuI complexes with a halide containing Cu4X4 core (X=iodide, bromide or chloride) and two 2-(diphenylphosphino)pyridine bridging ligands with a methyl group in para (4-Me) or ortho (6-Me) position of the pyridine ring. The structure of the electronic ground state is characterized by X-ray diffraction, NMR, and IR spectroscopy with the support of theoretical calculations. In contrast to the para system, the complexes with ortho-substituted bridging ligands show a remarkable and reversible temperature-dependent dual phosphorescence. Here, we combine for the first time the luminescence thermochromism with time-resolved FTIR spectroscopy. Thus, we receive experimental data on the structures of the two triplet states involved in the luminescence thermochromism. The transient IR spectra of the underlying triplet metal/halide-to-ligand charge transfer (3M /XLCT) and cluster-centered (3CC) states were obtained and interpreted by comparison with calculated vibrational spectra. The systematic and significant dependence of the bridging halides was analyzed. 相似文献
86.
Frontispiece: Distinct Spacing Between Anionic Groups: An Essential Chemical Determinant for Achieving Thiophene‐Based Ligands to Distinguish β‐Amyloid or Tau Polymorphic Aggregates
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87.
Maria Sadia M. Rasul Jan Jasmin Shah 《International journal of environmental analytical chemistry》2013,93(14):1537-1556
In this work functionalised mesoporous silica spheres have been utilised for the simultaneous preconcentration of nickel and cobalt. The silica spheres (SiSPs) prepared by the sol-gel method were functionalised with sodium diethyldithiocarbamate (DDTC-SiSPs). They were characterised by SEM, TEM, XRD, FTIR, CHN and nitrogen adsorption. The adsorption efficiency of DDTC-SiSPs was examined by batch equilibrium technique. The DDTC-SiSPs showed 100% adsorption for Ni (II) and Co (II). The effect of changing variables such as pH, shaking time, sample volume, preconcentration factor, eluent type and volume were investigated so as to obtain maximum recovery with high selectivity over interfering ions. The maximum adsorption capacity was found to be 15.15 mg g?1 and 11.80 mg g?1 for Ni (II) and Co (II) respectively using DDTC-SiSPs. 100% recovery was achieved with 5 mL of 2 M HNO3. The maximum preconcentration factor was 400 and the 3σ limits of detection were 0.201 µg L?1 and 0.198 µg L?1 for Ni (II) and Co (II) respectively. Thermodynamic studies showed that adsorption of Ni (II) and Co (II) on DDTC-SiSPs is exothermic with enthalpy changes of –0.514 KJ mol?1 and –0.854 KJ mol?1 for Ni (II) and Co (II) respectively. The method was applied to the preconcentration and determination of Ni (II) and Co (II) from tap, river and sea water. 相似文献
88.
Lisa Milchram Anita Fischer Jasmin Huber Regina Soldo Daniela Sieghart Klemens Vierlinger Stephan Blüml Günter Steiner Andreas Weinhusel 《Molecules (Basel, Switzerland)》2022,27(4)
For the identification of antigenic protein biomarkers for rheumatoid arthritis (RA), we conducted IgG profiling on high density protein microarrays. Plasma IgG of 96 human samples (healthy controls, osteoarthritis, seropositive and seronegative RA, n = 24 each) and time-series plasma of a pristane-induced arthritis (PIA) rat model (n = 24 total) were probed on AIT’s 16k protein microarray. To investigate the analogy of underlying disease pathways, differential reactivity analysis was conducted. A total of n = 602 differentially reactive antigens (DIRAGs) at a significance cutoff of p < 0.05 were identified between seropositive and seronegative RA for the human samples. Correlation with the clinical disease activity index revealed an inverse correlation of antibodies against self-proteins found in pathways relevant for antigen presentation and immune regulation. The PIA model showed n = 1291 significant DIRAGs within acute disease. Significant DIRAGs for (I) seropositive, (II) seronegative and (III) PIA were subjected to the Reactome pathway browser which also revealed pathways relevant for antigen presentation and immune regulation; of these, seven overlapping pathways had high significance. We therefore conclude that the PIA model reflects the biological similarities of the disease pathogenesis. Our data show that protein array analysis can elucidate biological differences and pathways relevant in disease as well be a useful additional layer of omics information. 相似文献
89.
Tassilo M. F. Restle Jasmin V. Dums Dr. Gabriele Raudaschl-Sieber Prof. Dr. Thomas F. Fässler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(30):6812-6819
The lithium phosphidoaluminate Li9AlP4 represents a promising new compound with a high lithium ion mobility. This triggered the search for new members in the family of lithium phosphidotrielates, and the novel compounds Li3AlP2 and Li3GaP2, obtained directly from the elements via ball milling and subsequent annealing, are reported here. It was unexpectedly found through band structure calculations that Li3AlP2 and Li3GaP2 are direct band gap semiconductors with band gaps of 3.1 and 2.8 eV, respectively. Rietveld analyses reveal that both compounds crystallize isotypically in the orthorhombic space group Cmce (no. 64) with lattice parameters of a=11.5138(2), b=11.7634(2) and c=5.8202(1) Å for Li3AlP2, and a=11.5839(2), b=11.7809(2) and c=5.8129(2) Å for Li3GaP2. The crystal structures feature TrP4 (Tr=Al, Ga) corner- and edge-sharing tetrahedra, forming two-dimensional layers. The lithium atoms are located between and inside these layers. The crystal structures were confirmed by MAS-NMR spectroscopy. 相似文献
90.