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61.
Yuen Cheong Tse Dr. Robert Hein Edward J. Mitchell Zongyao Zhang Prof. Paul D. Beer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(58):14550-14559
Anion receptors employing two distinct sensory mechanisms are rare. Herein, we report the first examples of halogen-bonding porphyrin BODIPY [2]rotaxanes capable of both fluorescent and redox electrochemical sensing of anions. 1H NMR, UV/visible and electrochemical studies revealed rotaxane axle triazole group coordination to the zinc(II) metalloporphyrin-containing macrocycle component, serves to preorganise the rotaxane binding cavity and dramatically enhances anion binding affinities. Mechanically bonded, integrated-axle BODIPY and macrocycle strapped metalloporphyrin motifs enable the anion recognition event to be sensed by the significant quenching of the BODIPY fluorophore and cathodic perturbations of the metalloporphyrin P/P+. redox couple. 相似文献
62.
Characterization of multiple fragmentation pathways initiated by collision‐induced dissociation of multifunctional anions formed by deprotonation of 2‐nitrobenzenesulfonylglycine 下载免费PDF全文
Tara E. Tovstiga Elizabeth A. L. Gillis J. Stuart Grossert Robert L. White 《Journal of mass spectrometry : JMS》2014,49(2):168-177
The correlation of anion structure with the fragmentation behavior of deprotonated nitrobenzenesulfonylamino acids was investigated using tandem mass spectrometry, isotopic labeling and computational methods. Four distinct fragmentation pathways resulting from the collision‐induced dissociation (CID) of deprotonated 2‐nitrobenzenesulfonylglycine (NsGly) were characterized. The unusual loss of the aryl nitro substituent as HONO was the lowest energy process. Subsequent successive losses of CO, HCN and SO2 indicated that an ortho cyclization reaction had accompanied loss of HONO. Other pathways involving rearrangement of the ionized sulfonamide group, dual bond cleavage and intramolecular nucleophilic displacement were proposed to account for the formation of phenoxide, arylsulfinate and arylsulfonamide product ions at higher collision energies. The four distinct fragmentation pathways were consistent with precursor–product relationships established by CID experiments, isotopic labeling results and the formation of analogous product ions from 2,4‐dinitrobenzenesulfonylglycine and the Ns derivatives of alanine and 2‐aminoisobutyric acid. The computations confirmed a low barrier for ortho cyclization with loss of HONO and feasible energetics for each reaction step in the four pathways. Computations also indicated that three of the fragmentation pathways started from NsGly ionized at the carboxyl group. Overall, the pathways identified for the fragmentation of the NsGly anion differed from processes reported for anions containing a single functional group, demonstrating the importance of functional group interactions in the fragmentation pathways of multifunctional anions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
63.
Dr. Nicholas H. Evans Prof. Paul D. Beer 《Angewandte Chemie (International ed. in English)》2014,53(44):11716-11754
Since the start of this millennium, remarkable progress in the binding and sensing of anions has been taking place, driven in part by discoveries in the use of hydrogen bonding, as well as the previously under‐exploited anion–π interactions and halogen bonding. However, anion supramolecular chemistry has developed substantially beyond anion recognition, and now encompasses a diverse range of disciplines. Dramatic advance has been made in the anion‐templated synthesis of macrocycles and interlocked molecular architectures, while the study of transmembrane anion transporters has flourished from almost nothing into a rapidly maturing field of research. The supramolecular chemistry of anions has also found real practical use in a variety of applications such as catalysis, ion extraction, and the use of anions as stimuli for responsive chemical systems. 相似文献
64.
A Flexible Solution to Anion Transport: Powerful Anionophores Based on a Cyclohexane Scaffold 下载免费PDF全文
James A. Cooper Steven T. G. Street Prof. Anthony P. Davis 《Angewandte Chemie (International ed. in English)》2014,53(22):5609-5613
Transmembrane anion carriers (anionophores) have potential for biological activity, including the treatment of channelopathies such as cystic fibrosis. A new family of anionophores has been synthesized, in which three thiourea groups are mounted on a cyclohexane‐based scaffold. Though conceptually related to earlier polycyclic systems, these molecules are simpler and far more accessible. Preorganization is somewhat reduced compared to earlier systems, and anion affinities are correspondingly lower. However, transport activities set new records. This surprising performance suggests a role for controlled flexibility in the design of transmembrane anion carriers. 相似文献
65.
Two macrocyclic zinc(II) complexes {[ZnL(VO3)2]·0.33H2O}n(1) and [ZnL(H2O)2][Ni(CN)4](2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [ZnL](ClO4)2 with NH4VO3 and K2[Ni(CN)4], respectively, and structurally characterized by elemental analysis, IR, XRPD, TG and X-ray diffraction. Single-crystal X-ray diffraction analyses indicated that the Zn(II) atom lies on an inversion center and is octahedrally coordinated by four nitrogen atoms of the tetradentate macrocyclic ligand in the equatorial plane and two oxygen atoms of [VO4] tetrahedra in the axial positions in 1, and two oxygen atoms of two water molecules in 2. Complex 1 shows a three-dimensional structure, which is constructed by the links of [VO3]nn- chains with [ZnL]2+, forming one-dimensional channels occupied by guest water molecules. The monomers of [ZnL(H2O)2]2+ and [Ni(CN)4]2- are connected through the intermolecular hydrogen bonds to form a two-dimensional sheet in complex 2. 相似文献
66.
67.
Dr. Pu Bai Dr. Zhuoya Dong Dr. Shuang Wang Dr. Xiangyu Wang Dr. Yue Li Dr. Yunzheng Wang Prof. Dr. Yanhang Ma Prof. Dr. Wenfu Yan Prof. Dr. Xiaodong Zou Prof. Dr. Jihong Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19707-19712
Cationic framework materials, especially pure inorganic cationic frameworks that can efficiently and selectively capture harmful heavy metal oxyanions from aqueous solution are highly desired yet scarcely reported. Herein, we report the discovery of a 2D cationic aluminum oxyhydroxide, JU-111, which sets a new benchmark for heavy metal oxyanion sorbents, especially for CrVI. Its structure was solved based on 3D electron diffraction tomography data. JU-111 shows fast sorption kinetics (ca. 20 min), high capture capacity (105.4 mg g−1), and broad working pH range (3–10) toward CrVI oxyanions. Unlike layered double hydroxides (LDHs), which are poorly selective in the presence of CO32−, JU-111 retains excellent selectivity for CrVI even under a large excess of CO32−. These superior features coupled with the ultra-low cost and environmentally benign nature make JU-111 a promising candidate for toxic metal oxyanion remediation as well as other potential applications. 相似文献
68.
Toshikatsu Sata Koji Matsusaki 《Journal of polymer science. Part A, Polymer chemistry》1996,34(11):2123-2133
Various anion exchange membranes containing the 4,4′-bipyridine moiety as anion exchange groups were prepared from membranous copolymers of chloromethylstyrene and divinylbenzene and membranes of chloromethylated polysulfone and 4,4′-bipyridine. After evaluating the electrochemical properties of the obtained anion exchange membranes, the effect of membrane species on the generation of a photovoltage was examined by irradiation using a xenon lamp. The membranes swelled with ethylene glycol were clamped between two ITO electrodes and sealed by adhesive. The generated photovoltage and photocurrent from about a 120 μm thick membrane were about 80 mV and 400 nA, respectively, in a 200K Ω load resistance, though dependent of membrane species. The voltage decreased with increasing crosslinking by the divinylbenzene in the copolymer membranes. The effect of counter ion species on the voltage was examined and a chloride ion form of membrane showed the highest photovoltage. The membranes with different thicknesses, which were prepared from polysulfone derivatives, were evaluated and the voltage decreased with decreasing thickness. Even a porous membrane from polysulfone derivatives showed a photovoltage though a porous membrane in which a methyl viologen ethylene glycol solution had been impregnated did not have a stable voltage. Also, the anion exchange membrane containing the benzyl trimethylammonium moiety, which is the conventional anion exchange groups, did not show a high and stable photovoltage upon photoirradiation. © 1996 John Wiley & Sons, Inc. 相似文献
69.
Alkaline stable anion exchange membranes based on the cross-linked poly(arylene ether sulfone) grafted with dual quaternary piperidine (XPAES-DP) units were synthesized. The chemical structure of the synthesized PAES-DP was validated using 1H-NMR and FT-IR spectroscopy. The physicochemical, thermal, and mechanical properties of XPAES-DP membranes were compared with those of two linear PAES based membranes grafted with single piperidine (PAES-P) unit and conventional trimethyl amine (PAES-TM). XPAES-DP membrane showed the ionic conductivity of 0.021 S cm−1 at 40 °C which was much higher than that of PAES-P and PAES-TM because of the possession of more quaternary ammonium groups in the cross-linked structure. This cross-linked structure of the XPAES-DP membrane resulted in a higher tensile strength of 18.11 MPa than that of PAES-P, 17.09 MPa. In addition, as the XPAES-DP membrane shows consistency in the ionic conductivity even after 96 h in 3 M KOH solution with a minor change, its chemical stability was assured for the application of anion exchange membrane fuel cell. The single-cell assembled with XPAES-DP membrane displayed a power density of 109 mWcm−2 at 80 °C under 100% relative humidity. 相似文献
70.
对基于(C—H)+…X-氢键类型的阴离子识别以及识别过程所引起的光化学传感和电化学传感的研究进展进行了评述. 相似文献