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51.
Murugan Muthtamilselvan 《Journal of Applied Analysis & Computation》2019,9(2):615-627
The aim of the study is to examine the stagnation point flow of a dusty Casson fluid over a stretching sheet with thermal radiation and buoyancy effects. The governing boundary layer equations are represented by a system of partial differential equation. After applying suitable similarity transformations, the resulting boundary layer equations are solved numerically using the Runge Kutta Fehlberg fourth-fifth order method (RKF-45 method). The behaviors of velocity, temperature and concentration profiles of fluid and dusty particles with respect to change in fluid particle interaction parameter, Casson paramter, Grashof number, radiation parameter, Prandtl number, number density, thermal equilibrium time, relaxation time, specific heat of fluid and dusty particles, ratio of diffusion coefficients, Schmidt number and Eckert number are analysed graphically and discussed. Our computed results interpret that velocity distribution decays for higher estimation of Casson parameter while temperature distribution shows increasing behavior for larger radiation parameter. 相似文献
52.
Ehsan Zeimaran Sara Pourshahrestani Nahrizul Adib Kadri Daniel Kong Seyed Farid Seyed Shirazi Sangeetha Vasudevaraj Naveen S. S. Murugan T. S. Kumaravel Babak Salamatinia 《Macromolecular bioscience》2019,19(10)
Stretchable self‐healing urethane‐based biomaterials have always been crucial for biomedical applications; however, the strength is the main constraint of utilization of these healable materials. Here, a series of novel, healable, elastomeric, supramolecular polyester urethane nanocomposites of poly(1,8‐octanediol citrate) and hexamethylene diisocyanate reinforced with cellulose nanocrystals (CNCs) are introduced. Nanocomposites with various amounts of CNCs from 10 to 50 wt% are prepared using solvent casting technique followed by the evaluation of their microstructural features, mechanical properties, healability, and biocompatibility. The synthesized nanocomposites indicate significantly higher tensile modulus (approximately 36–500‐fold) in comparison to the supramolecular polymer alone. Upon exposure to heat, the materials can reheal, but nevertheless when the amount of CNC is greater than 10 wt%, the self‐healing ability of nanocomposites is deteriorated. These materials are capable of rebonding ruptured parts and fully restoring their mechanical properties. In vitro cytotoxicity test of the nanocomposites using human dermal fibroblasts confirms their good cytocompatibility. The optimized structure, self‐healing attributes, and noncytotoxicity make these nanocomposites highly promising for tissue engineering and other biomedical applications. 相似文献
53.
R. Murugan V. Thangadurai W. Weppner 《Applied Physics A: Materials Science & Processing》2008,91(4):615-620
We report systematic studies on the transport properties by varying the lithium oxide content of the garnet-based solid electrolyte
Li5+xBaLa2Ta2O11.5+0.5x (x=0, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75, 2.00) for understanding the ionic conductivity dependence on the crystal lattice
parameter and carrier concentration. Powder X-ray diffraction data of Li5+xBaLa2Ta2O11.5+0.5x (x=0, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75, 2.00) indicate the existence of the garnet-like structure for any of the compositions.
The cubic lattice parameter was found to increase with increasing x and reaches a maximum at x=1.00, then decreases slightly
with a further increase in x. Impedance measurements obtained at 50 °C indicate a maximum of the grain-boundary resistance
(Rgb) contribution to the total resistance (Rb+Rgb) at x=0.0 and a considerable decrease with increase in lithium concentration. The total (bulk + grain-boundary) and bulk
ionic conductivity increase with increasing lithium content and reach a maximum at x=1.00 and then decrease slightly with
further increase in x. Among the investigated compounds, Li6BaLa2Ta2O12 exhibits the highest total (bulk + grain-boundary) and bulk ionic conductivity of 1.5×10-4 and 1.8×10-4 S/cm at 50 °C, respectively. The results obtained in the present investigation of the Li5+xBaLa2Ta2O11.5+0.5x (x=0–2) series clearly revealed that the lithium content plays a major role in decreasing the grain boundary resistance contribution
to the total resistance and also in increasing the ionic conductivity of the garnet-like compound.
PACS 66.10.Ed; 82.45.Gj; 82.47.Aa 相似文献
54.
Muniyappan Boominathan Jeyavelraman Kiruthika Murugan Arunachalam 《Journal of polymer science. Part A, Polymer chemistry》2019,57(14):1508-1515
A pillar[5]arene pendant polymer (Poly‐P[5]A) is synthesized via ROMP using Grubb's first‐generation catalyst. GPC analysis of the polymer suggested ~30 pendant pillar[5]arene units in the polymer. Supramolecular polypseudorotaxane assembly is constructed by intermolecularly crosslinking pendant pillar[5]arene units using a bispyridinium guest via host–guest complexation. Formation of the polypseudorotaxane assembly is characterized by 1D/2D NMR techniques and DLS analysis. Moreover, anion‐responsiveness of the polypseudorotaxane assembly is demonstrated by 1H NMR spectroscopic analysis using chloride anion as external stimulus. Scanning electron microscopic analysis of the poly‐P[5]A showed breath‐figure assembly and upon crosslinking with G.2PF6 the polymer self‐assemble to give a supramolecular polymer network. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1508–1515 相似文献
55.
Murugan Subaramanian Vinod G. Landge Akash Mondal Virendrakumar Gupta Ekambaram Balaraman 《化学:亚洲杂志》2019,14(24):4557-4562
A molecularly defined NiII‐complex catalyzing the chemoselective acetalization of aldehydes with alcohols under neutral conditions is reported. The reaction is general, efficient and showed a wide substrate scope (including aliphatic aldehydes) as well as excellent functional group tolerance. Reusability of the present nickel catalyst is also demonstrated. 相似文献
56.
P. Laavanya K. Panchanatheswaran M. N. Arumugam S. Arunachalam 《Journal of chemical crystallography》1998,28(1):83-86
An octahedral geometry for the molecule of the title complex with very slight distortions around Co(III) is confirmed by single-crystal X-ray diffraction study. The molecular structure of the complex has been shown to contain two dodecylamine moieties in the trans orientations, two N-bonded dimethylglyoximato (DMG) groups and an uncoordinated nitrite ion. 相似文献
57.
Kadarkarai Murugan Jagannathan Madhavan Christina Mary Samidoss Chellasamy Panneerselvam Al Thabiani Aziz Arumugam Malathi Aruliah Rajasekar Amuthavalli Pandiyan Suresh Kumar Abdullah A. Alarfaj Akon Higuchi Giovanni Benelli 《Journal of Cluster Science》2018,29(2):337-344
Anopheles stephensi is a mosquito vector of malaria, which is still considered a relevant public health problem due to increasing outdoor transmission, growing resistance to insecticides used to target vectors, and antiplasmodial drugs as well. Thus, there is a vital need to explore novel sources of effective compounds. In this study, the hydrothermal method was used for the synthesis of bismuth oxyiodide (BiOI) nanoflakes. Furthermore, the toxicity of BiOI nanoflakes was evaluated for the first time on A. stephensi, as well as in vivo against the malaria parasite Plasmodium berghei. The synthesis of BiOI nanoflakes was confirmed by various characterization techniques, including X-ray diffraction, Fourier transform-infrared spectroscopy, field emission scanning electron microscopy and transmission electron microscopy (HR-TEM). LC50 of BiOI nanoflakes on A. stephensi were 2.263 ppm (larva I), 3.414 ppm (II), 4.956 ppm (III), 6.983 ppm (IV) and 8.605 ppm (pupae). In vivo antiplasmodial experiments conducted on P. berghei infecting albino mice showed 27.2% of chemosuppression after 4 days of treatment with 300 mg/kg/day of BiOI, a lower performance if compared to chloroquine. Overall, our results suggested that hydrothermal synthesis of BiOI nanoflakes may be considered to develop newer and safer tools for malaria vector control. 相似文献
58.
Lithium garnet based free-standing solid polymer composite membrane for rechargeable lithium battery
Electrolytes with high lithium-ion conductivity, better mechanical strength and large electrochemical window are essential for the realization of high-energy density lithium batteries. Polymer electrolytes are gaining interest due to their inherent flexibility and nonflammability over conventional liquid electrolytes. In this work, lithium garnet composite polymer electrolyte membrane (GCPEM) consisting of large molecular weight (Wavg ~?5?×?106) polyethylene oxide (PEO) complexed with lithium perchlorate (LiClO4) and lithium garnet oxide Li6.28Al0.24La3Zr2O12 (Al-LLZO) is prepared by solution-casting method. Significant improvement in Li+ conductivity for Al-LLZO containing GCPEM is observed compared with the Al-LLZO free polymer membrane. Maximized room temperature (30 °C) Li+ conductivity of 4.40?×?10?4 S cm?1 and wide electrochemical window (4.5 V) is observed for PEO8/LiClO4?+?20 wt% Al-LLZO (GCPEM-20) membrane. The fabricated cell with LiCoO2 as cathode, metallic lithium as anode and GCPEM-20 as electrolyte membrane delivers an initial charge/discharge capacity of 146 mAh g?1/142 mAh g?1 at 25 °C with 0.06 C-rate. 相似文献
59.
Roos PH Venkatachalam A Manz A Waentig L Koehler CU Jakubowski N 《Analytical and bioanalytical chemistry》2008,392(6):1135-1147
Numerous structurally and enzymatically similar cytochromes P450 (CYPs) are involved in the metabolism of xenobiotics and
are present in different amounts and with different enzyme profiles in human tissues and cells. Analysis of their adaptively
regulated and individually variable patterns is a peculiar analytical challenge. We developed a laser ablation inductively
coupled plasma mass spectrometry (LA-ICP-MS) based method for concomitant detection and semiquantitative determination of
electrophoretically separated and blotted CYPs. The first results are given here for the two enzymes CYP1A1 and CYP2E1. Specific
monoclonal antibodies directed against the enzymes were differentially labelled with europium via a covalently linked chelator
and with iodine, respectively. Analysis of the modified antibodies shows that both europium and iodine are coupled to the
heavy and the light chains of the antibodies. Also, the antibodies maintained their antigen-binding properties after labelling
as demonstrated by LA-ICP-MS-analysed immunoblots. The method allowed us to detect specifically and concomitantly both CYP
enzymes in complex biological samples, i.e. microsomes of rat liver and minipig duodenum, which are characterized by different
levels and proportions of the two CYP enzymes. A strong CYP1A1 signal is found in liver microsomes of 3-methylcholanthrene-treated
rats, while it is (nearly) absent in liver microsomes of rats treated with isonocotinic acid hydrazide (isoniazid). The constitutively
expressed CYP2E1 is found in microsomes of both treatment groups. Duodenal microsomes of minipigs orally exposed to polycyclic
aromatic hydrocarbons show a clear CYP1A1 signal. Low levels of CYP2E1 can also be detected in these microsomes. The LA-ICP-MS
method allows concomitant determination of CYPs, thereby exhibiting sensitivity similar to that of conventional chemoluminescence
detection via peroxidase-labelled secondary antibodies. The latter method allows readout of a single CYP protein in a 1D separation.
Although the results presented here are only for labelling by use of the elements iodine and europium, the same strategy can
be applied also for other lanthanide elements in combination with chelating compounds, so LA-ICP-MS of western blots offers
a new capability to be applied for highly multiplexed CYP determinations via labelled antibodies. 相似文献
60.
Solvation shell structure of a 7-piperidino-5,9-methanobenzo[8] annulene (PMA) in water has been investigated in ambient conditions using both molecular dynamics (MD) and Car-Parrinello molecular dynamics (CPMD) calculations. From the MD calculations, we find that this molecule exists in three major conformational states out of which two are in twist-boat forms and one in chair form. Due to the limited time scale accessible in CPMD simulations, we have studied all the three conformational states separately using CPMD. The molecular geometry, electronic charge distribution and solvation structure for all three forms are investigated. The stability order of the chair and twist-boat conformations in water solvent has been reversed when compared to the gaseous phase results and in the case of polar aprotic solvents (J. Org. Chem., 1999, 61, 5979). From the radial distribution function, we find that the solvent density around the chair form is significantly lower, which has to be directly related to the smaller solvent accessible area for this conformation and this is in complete agreement with earlier reports. Among the findings are that the solvation shell structure around the nitrogen atom in the chair form of PMA is considerably different from the open conformational forms or the twist-boat forms. The dipole moment for the closed form is found to be significantly larger when compared to the twist-boat forms. 相似文献