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81.
Nenov A Cordes T Herzog TT Zinth W de Vivie-Riedle R 《The journal of physical chemistry. A》2010,114(50):13016-13030
A combined experimental and theoretical investigation of photoinduced Z/E isomerizations is presented. Unsubstituted Hemithioindigo is selected as a representative minimal model to unravel the reaction mechanism in the presence of heteroatoms on an atomic level. Time-resolved spectroscopy reveals multiexponential reaction dynamics on the few picoseconds time scale, which are interpreted by quantum chemical calculations at the CASSCF/CASPT2 level of theory. Detailed insight into the processes governing the ultrafast decay from the first excited state, mediated by a number of conical intersections, is provided. Charge separation and charge balance recovery on the reaction pathway play the leading role and are controlled by the electron-donating or -withdrawing character of the heteroatoms. The electronic and geometric structures of the individual minimum energy conical intersections governing the reaction are rationalized, and an extended energetically low lying conical intersection seam is extracted. Comparison to the experimental results permits linking the observed time constants to molecular intermediates and pathways. An explanation is provided for the pronounced differences of Z → E and the E → Z photoreactions upon excitation to the first excited singlet state. 相似文献
82.
Different hydrates of calcium oxalate have been electrodeposited by electrogeneration of acid at the anode from an EDTA-stabilized calcium nitrate bath containing dissolved oxalate ions. The deposition is controlled by varying the bath pH, temperature, and current density. Formation of metastable CaC2O4·2H2O is favored at high current densities at ambient temperature, whereas the thermodynamically stable CaC2O4·H2O is formed at elevated bath temperatures. Both the polymorphs show oriented growth with respect to the substrate normal under different deposition conditions. 相似文献
83.
Vishnu J. Ram Vidyottama Dube Luc A. C. Pieters Arnold J. Vlietinck 《Journal of heterocyclic chemistry》1989,26(3):625-628
Various bis[4-aryl/alkyl-1, 2, 4-triazoline-5-thione-3-yl]alkanes ( 3 ) were prepared from base cyclization of bis thiosemicarbazide 2 and transformed into sulphides by reaction with different alkyl halides in alkaline medium. These compounds were further oxidised to sulphones 5 with acidic potassium permanganate. 1-Aryl-3-[4-(4-aryl/alkyl-1, 2, 4-triazoline-3-thione-5-yl)phenyl]thioureas ( 8 ) were prepared in two steps from p-aminophenylhydrazide ( 6 ) and aryl/alkylisothiocyanates. Alkylation of 8 with different alkyl halides yielded exclusively sulphides 9 . Some sulphides 12 and Mannich bases 13 from 5-(p-fluorophenyl)-1, 3, 4-oxadiazol-2-thione ( 11 ) were also prepared to evaluate their pesticidal activities. All the prepared compounds were screened for pesticidal activities but none of them exhibited any significant activity. 相似文献
84.
Interactive System for Similarity-Based Inspection and Assessment of the Well-Being of mHealth Users
Subash Prakash Vishnu Unnikrishnan Rüdiger Pryss Robin Kraft Johannes Schobel Ronny Hannemann Berthold Langguth Winfried Schlee Myra Spiliopoulou 《Entropy (Basel, Switzerland)》2021,23(12)
Recent digitization technologies empower mHealth users to conveniently record their Ecological Momentary Assessments (EMA) through web applications, smartphones, and wearable devices. These recordings can help clinicians understand how the users’ condition changes, but appropriate learning and visualization mechanisms are required for this purpose. We propose a web-based visual analytics tool, which processes clinical data as well as EMAs that were recorded through a mHealth application. The goals we pursue are (1) to predict the condition of the user in the near and the far future, while also identifying the clinical data that mostly contribute to EMA predictions, (2) to identify users with outlier EMA, and (3) to show to what extent the EMAs of a user are in line with or diverge from those users similar to him/her. We report our findings based on a pilot study on patient empowerment, involving tinnitus patients who recorded EMAs with the mHealth app TinnitusTips. To validate our method, we also derived synthetic data from the same pilot study. Based on this setting, results for different use cases are reported. 相似文献
85.
86.
Kowit Hengphasatporn Benyapa Kaewmalai Somruedee Jansongsaeng Vishnu Nayak Badavath Thanaphon Saelee Thamonwan Chokmahasarn Tanatorn Khotavivattana Yasuteru Shigeta Thanyada Rungrotmongkol Siwaporn Boonyasuppayakorn 《Molecules (Basel, Switzerland)》2021,26(22)
A flavonoid is a versatile core structure with various cellular, immunological, and pharmacological effects. Recently, flavones have shown anti-dengue activities by interfering with viral translation and replication. However, the molecular target is still elusive. Here we chemically modified apigenin by adding an alkyne moiety into the B-ring hydroxyl group. The alkyne serves as a chemical tag for the alkyne-azide cycloaddition reaction for subcellular visualization. The compound located at the perinuclear region at 1 and 6 h after infection. Interestingly, the compound signal started shifting to vesicle-like structures at 6 h and accumulated at 24 and 48 h after infection. Moreover, the compound treatment in dengue-infected cells showed that the compound restricted the viral protein inside the vesicles, especially at 48 h. As a result, the dengue envelope proteins spread throughout the cells. The alkyne-tagged apigenin showed a more potent efficacy at the EC50 of 2.36 ± 0.22, and 10.55 ± 3.37 µM, respectively, while the cytotoxicities were similar to the original apigenin at the CC50 of 70.34 ± 11.79, and 82.82 ± 11.68 µM, respectively. Molecular docking confirmed the apigenin binding to the previously reported target, ribosomal protein S9, at two binding sites. The network analysis, homopharma, and molecular docking revealed that the estrogen receptor 1 and viral NS1 were potential targets at the late infection stage. The interactions could attenuate dengue productivity by interfering with viral translation and suppressing the viral proteins from trafficking to the cell surface. 相似文献
87.
88.
Manisha Gurnani Prangya Rath Abhishek Chauhan Anuj Ranjan Arabinda Ghosh Rup Lal Nobendu Mukerjee Nada H. Aljarba Saad Alkahtani Vishnu D. Rajput Svetlana Sushkova Evgenya V. Prazdnova Tatiana Minkina Tanu Jindal 《Molecules (Basel, Switzerland)》2022,27(6)
Antibiotic resistance is one of the major growing concerns for public health. Conventional antibiotics act on a few predefined targets and, with time, several bacteria have developed resistance against a large number of antibiotics. The WHO has suggested that antibiotic resistance is at a crisis stage and identification of new antibiotics and targets could be the only approach to bridge the gap. Filamentous Temperature Sensitive-Mutant Z (Fts-Z) is one of the promising and less explored antibiotic targets. It is a highly conserved protein and plays a key role in bacterial cell division by introducing a cytokinetic Z-ring formation. In the present article, the potential of over 165 cyanobacterial compounds with reported antibiotic activity against the catalytic core domain in the Fts-Z protein of the Bacillus subtilis was studied. The identified cyanobacterial compounds were screened using the GLIDE module of Maestro v-2019-2 followed by 100-ns molecular dynamics (MD) simulation. Ranking of the potential compound was performed using dock score and MMGBSA based free energy. The study reported that the docking score of aphanorphine (−6.010 Kcalmol−1) and alpha-dimorphecolic acid (ADMA) (−6.574 Kcalmol−1) showed significant role with respect to the reported potential inhibitor PC190723 (−4.135 Kcalmol−1). A 100 ns MD simulation infers that Fts-Z ADMA complex has a stable conformation throughout the progress of the simulation. Both the compounds, i.e., ADMA and Aphanorphine, were further considered for In-vitro validation by performing anti-bacterial studies against B. subtilis by agar well diffusion method. The results obtained through In-vitro studies confirm that ADMA, a small molecule of cyanobacterial origin, is a potential compound with an antibacterial activity that may act by inhibiting the novel target Fts-Z and could be a great drug candidate for antibiotic development. 相似文献
89.
A plot of negative logarithm of the electrical conductance (K)vs reciprocal of the absolute temperature (T) shows the existence of the transition in the systems ‘Electrolyte-Sucrose-water’, ‘Electrolyte-Mannitol-water’, and ‘Electrolyte-Xylose-water’. A saturated solution of sucrose/mannitol/xylose containing a known amount of an electrolyte was prepared at a temperature of 50·0±0·05° C and the crystals were separated by centrifugation at the same temperature. The conductance of the centrifugate was measured in a tubular conductivity cell at different temperatures in the range between 30° C to 70° C. The plot of ?log10 Kvs 1/T showed a break at the saturation temperature, the point where two straight lines appeared to intersect. The transition can be explained on the basis of change in the water structure due to the presence of ‘structure-breaking’ and/or ‘structure-making’ ions. These sucrose, xylose, and mannitol molecules due to the presence of a number of hydrogen bonding sites contribute largely toward the build up of big structures in the supersaturated state. These structures crumble as the system undergoes the transition at the saturation temperature. Different electrolytes produced more or less similar effect. 相似文献
90.