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71.
Kinetic energy released per unit mass relative to air and energy absorption buildup factors has been calculated for some potential bioactive compounds in the energy region of 0.015–15?MeV. The bioactive compounds of 1-aryl-3-dibenzylamino-propane-1-on hydrochloride type Mannich bases were used in this work. Aryl part was changed as C6H5 (1), 4-CH3C6H4 (2), C4H3S-2-yl (3), 4-FC6H4 (4), 4-BrC6H4 (5), 4-ClC6H4 (6), and 4-NO2C6H4 (7). The energy absorption buildup factors have been calculated for penetration depth of 40 mean free paths. It is observed that kinetic energy released per unit mass relative to air depends on the photon energy and chemical content of compounds. The compounds with least mean atomic number possess the maximum value of energy absorption buildup factors. Also, the energy absorption buildup factors are found the highest in intermediate energy, whereas the lowest in low as well as high energies. 相似文献
72.
Arif Sanli Ozlem Celebi Mehmet Eken Alev Oktay Sedat Aydin Emin Ayduran 《Journal of voice》2008,22(2):238-244
SUMMARY: Visualization of enlarged laryngeal lesions is the most important factor in choosing a surgical technique, especially for partial surgery. For this reason standard microlaryngoscopy, a computed tomography (CT) scan of the larynx, and 30 degrees telescopic microlaryngoscopy were compared during evaluation of the laryngeal ventricul and sub-glottic area. The histopatholgoical findings of the specimens collected under each modality were simultaneously compared. Comparison of the histopathological findings, which corresponded to inspection with the 30 degrees telescopic method, was more significant than with the use of standard microlaryngoscopy or the CT scan. The aim of the current study therefore was to determine the importance of the 30 degrees telescopic microlaryngoscopic method for the evaluation of the laryngeal ventricle and subglottic area. 相似文献
73.
Rabia Zeynep Uslu Kobak Duygu Akyüz Atıf Koca 《Journal of Solid State Electrochemistry》2016,20(5):1311-1321
Metallophthalocyanines (MPcs) (M = 2H+, Zn2+, Co2+, and Cu2+) bearing diethylaminophenoxy and chloro substituents at the peripheral positions (MPc-tdea-tCl) were coated on the working electrodes with the electropolymerization and tested as electrochromic materials. Altering the metal center of MPcs affected the redox activities of MPc-tdea-tCl films. All electropolymerized MPc-tdea-tCl films behaved as conductive and redox active films in different electrolyte systems. Electrochromic properties of MPc-tdea-tCl films were investigated via the voltammetric, in situ spectroelectrochemical, and in situ spectroelectrocolorimetric measurements. H 2 Pc-tdea-tCl film did not give any electrochromic response, while ZnPc-tdea-tCl and CuPc-tdea-tCl films behave as a reasonable electrochromic material. Distinctive color changes with short response times, high optical contrast, and better optical and coulombic stabilities were only observed with CoPc-tdea-tCl film. 相似文献
74.
Zeynep Gönül Dilara Altay Öztürk Fatümetüzzehra Küçükbay Suat Tekin Zehra Tekin Hasan Küçükbay 《Journal of heterocyclic chemistry》2023,60(1):86-95
In this study, 10 new indole-dipeptide conjugates were synthesized, and their anticancer activity was determined against on A2780 (ovarian cancer cell line) and MCF-7 (breast cancer cell line) cells. Among compounds, 5 and 10 showed better activity against A2780 cell lines than the standard drug docatexel at 0.1 and 1 μM concentrations, while only compound 5 showed better activity than docatexel, the MCF-7 cell line at 0.1 and 1 μM concentrations. The antioxidant potencies of the compounds were low in both the DPPH and iron reducing power methods tested when compared to standard antioxidants used in this work. 相似文献
75.
Zeynep Kurkcuoglu Panagiotis I. Koukos Nevia Citro Mikael E. Trellet J. P. G. L. M. Rodrigues Irina S. Moreira Jorge Roel-Touris Adrien S. J. Melquiond Cunliang Geng Jörg Schaarschmidt Li C. Xue Anna Vangone A. M. J. J. Bonvin 《Journal of computer-aided molecular design》2018,32(1):175-185
We present the performance of HADDOCK, our information-driven docking software, in the second edition of the D3R Grand Challenge. In this blind experiment, participants were requested to predict the structures and binding affinities of complexes between the Farnesoid X nuclear receptor and 102 different ligands. The models obtained in Stage1 with HADDOCK and ligand-specific protocol show an average ligand RMSD of 5.1 Å from the crystal structure. Only 6/35 targets were within 2.5 Å RMSD from the reference, which prompted us to investigate the limiting factors and revise our protocol for Stage2. The choice of the receptor conformation appeared to have the strongest influence on the results. Our Stage2 models were of higher quality (13 out of 35 were within 2.5 Å), with an average RMSD of 4.1 Å. The docking protocol was applied to all 102 ligands to generate poses for binding affinity prediction. We developed a modified version of our contact-based binding affinity predictor PRODIGY, using the number of interatomic contacts classified by their type and the intermolecular electrostatic energy. This simple structure-based binding affinity predictor shows a Kendall’s Tau correlation of 0.37 in ranking the ligands (7th best out of 77 methods, 5th/25 groups). Those results were obtained from the average prediction over the top10 poses, irrespective of their similarity/correctness, underscoring the robustness of our simple predictor. This results in an enrichment factor of 2.5 compared to a random predictor for ranking ligands within the top 25%, making it a promising approach to identify lead compounds in virtual screening. 相似文献
76.
Zeynep Mutlu Mayank Jain Sung Ho Yook Mukerrem Cakmak 《Journal of polymer science. Part A, Polymer chemistry》2021,59(18):2045-2056
Mechano-optical behavior and related structural evolution during uniaxial stretching of melt miscible poly (ethylene terephthalate) (PET)/poly (ether imide) (PEI) blends were studied near their glass transition temperature using an instrumented machine that measures true stress, true strain and spectral birefringence simultaneously. Stretching from amorphous state, two distinct stress-optical regimes were observed at temperatures between Tg and Tcc (cold crystallization). Near Tg, a typical photoelastic behavior persists until a critical temperature above which temperature independent initial stress optical behavior is observed. At those temperatures above Tg, where glassy behavior is observed, decreasing stretching rate was also found to eliminate this glassy photo elastic regime leading to the observation of a linear initial stress optical behavior that becomes temperature independent as expected from linear stress optical rule. Increasing PEI concentration in the blends suppresses crystallizability and increases temperature at which initial elastic region disappears giving way to pure liquid behavior where linear stress optical behavior is observed. This is attributed to the increase and broadening of the glass transition temperature with the addition of noncrystallizable PEI. In PET/PEI blends, the stress-optical coefficient (SOC), determined in a linear stress optical regime, was found to increase linearly with the increase in PEI concentration. 相似文献
77.
JPC – Journal of Planar Chromatography – Modern TLC - α-Cypermethrin is a synthetic pyrethroid insecticide used to control insects. In soil, α-cypermethrin biodegrades... 相似文献
78.
Zeynep anl Tuncay Krolu Bahadr
zgür Güler 《Mathematical Methods in the Applied Sciences》2019,42(16):5403-5415
In this paper, the normalizers of , for k = 2 or 3, in the groups Γk of modular group Γ are given by using the concept of Γk axes of the set of left cosets of , on which Γk acts transitively, in Γk. 相似文献
79.
Akgun Z Engelbrecht H Fan KH Barnes CL Cutler CS Jurisson SS Lever SZ 《Dalton transactions (Cambridge, England : 2003)》2010,39(42):10169-10178
(103)Rhodium(III) complexes derived from seven acyclic tetradentate N(2)S(2) ligands (one diaminedithiol and six diaminedithioether ligands) have been synthesized and characterized. Structural variations in the ligand include the length of carbon backbone between the coordinating atoms (222; 232; 323; 333), the presence or absence of gem-dimethyl groups α to sulfur, and the nature of the organic moiety on the sulfurs (hydrogen, p-methoxybenzyl and methyl). For each ligand, the formation of cis and/or trans dichloro isomeric complexes was assessed. Two complexes have been further characterized by single crystal X-ray diffraction. Preparation of the (103)Rhodium(III) complexes was conducted and overall radiochemical yields, in vitro stability and log D(7.4) values were measured. From these studies, the ligand with the 232 chain length, gem-dimethyl groups and the methyl thioether (L4) emerged as a preferred ligand for formation of rhodium complexes with trans geometry and highest radiochemical yields. 相似文献
80.
A simple and sensitive method has been developed and validated for the determination of aliskiren (ALS) in its dosage forms
and spiked plasma. The method was based on the reaction of the drug with dansyl chloride in the presence of bicarbonate solution
of pH 10.5 to give a highly fluorescent derivative which was measured at 501 nm with excitition at 378 nm in dichloromethane.
Different experimental parameters affecting the development of the method and stability were carefully studied and optimized.
The calibration curves were linear over the concentration ranges of 100–700 and 50–150 ng/mL for standard solution and plasma,
respectively. The limits of detection were 27.52 ng/mL in standard solution, 4.91 ng/mL in plasma. The developed method was
successfully applied to the analysis the drug in the commercial tablets and spiked plasma samples. The mean recovery of ALS
from tablets and plasma was 100.10 and 97.81%, respectively. A proposal of the reaction pathway was presented. 相似文献