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371.
Manju Sebastian V. Arun P.P. Robinson Annu Anna Varghese Rani Abraham E. Suresh K.K. Mohammed Yusuff 《Polyhedron》2010
Five new transition metal complexes [MnL(OAc)]·H2O (1), [FeLCl2] (2), [NiL2]·H2O (3), [CuLCl] (4) and [ZnL2]·2H2O (5) have been synthesized using a tridentate Schiff base ligand, HL (quinoxaline-2-carboxalidine-2-amino-5-methylphenol) and the complexes have been characterized by physicochemical and spectroscopic techniques. The spectral analyses reveal an octahedral geometry for 3, square pyramidal structure for 2 and square planar structure for 4. Analytical and physicochemical data indicate tetrahedral structure for 1 and octahedral structure for 5. The crystallographic study reveals that [NiL2]·H2O shows distorted octahedral geometry with a cis arrangement of N4O2 donor set of the bis Schiff base and exhibits a two-dimensional polymeric structure parallel to [0 1 0] plane. The complexes were screened for catalytic phenol hydroxylation reaction. Coordinatively unsaturated manganese(II), iron(III) and copper(II) complexes were found to be active catalysts. The poor catalytic activity of the nickel(II) complex is due to coordinatively saturated octahedral nature of the complex. Maximum conversion of phenol was observed for the copper(II) complex and the major product was catechol. 相似文献
372.
Nur Hanisah Mustafa Mahendran Sekar Shivkanya Fuloria M. Yasmin Begum Siew Hua Gan Nur Najihah Izzati Mat Rani Subban Ravi Kumarappan Chidambaram Vetriselvan Subramaniyan Kathiresan V. Sathasivam Srikanth Jeyabalan Subasini Uthirapathy Sivasankaran Ponnusankar Pei Teng Lum Vijay Bhalla Neeraj Kumar Fuloria 《Molecules (Basel, Switzerland)》2022,27(6)
Sarsasapogenin is a natural steroidal sapogenin molecule obtained mainly from Anemarrhena asphodeloides Bunge. Among the various phytosteroids present, sarsasapogenin has emerged as a promising molecule due to the fact of its diverse pharmacological activities. In this review, the chemistry, biosynthesis and pharmacological potentials of sarsasapogenin are summarised. Between 1996 and the present, the relevant literature regarding sarsasapogenin was obtained from scientific databases including PubMed, ScienceDirect, Scopus, and Google Scholar. Overall, sarsasapogenin is a potent molecule with anti-inflammatory, anticancer, antidiabetic, anti-osteoclastogenic and neuroprotective activities. It is also a potential molecule in the treatment for precocious puberty. This review also discusses the metabolism, pharmacokinetics and possible structural modifications as well as obstacles and opportunities for sarsasapogenin to become a drug molecule in the near future. More comprehensive preclinical studies, clinical trials, drug delivery, formulations of effective doses in pharmacokinetics studies, evaluation of adverse effects and potential synergistic effects with other drugs need to be thoroughly investigated to make sarsasapogenin a potential molecule for future drug development. 相似文献
373.
Geethanjali Thayumanavan Srikanth Jeyabalan Shivkanya Fuloria Mahendran Sekar Monica Ravi Logesh Kumar Selvaraj Logeshwari Bala Kumarappan Chidambaram Siew Hua Gan Nur Najihah Izzati Mat Rani M. Yasmin Begum Vetriselvan Subramaniyan Kathiresan V. Sathasivam Dhanalekshmi U. Meenakshi Neeraj Kumar Fuloria 《Molecules (Basel, Switzerland)》2022,27(8)
Bisphenol A (BPA), a well-known xenoestrogen, is commonly utilised in the production of polycarbonate plastics. Based on the existing evidence, BPA is known to induce neurotoxicity and behavioural issues. Flavonoids such as silibinin and naringenin have been shown to have biological activity against a variety of illnesses. The current research evaluates the neuropharmacological effects of silibinin and naringenin in a zebrafish model against neurotoxicity and oxidative stress caused by Bisphenol A. In this study, a novel tank diving test (NTDT) and light–dark preference test (LDPT) were used in neurobehavioural investigations. The experimental protocol was planned to last 21 days. The neuroprotective effects of silibinin (10 μM) and naringenin (10 μM) in zebrafish (Danio rerio) induced by BPA (17.52 μM) were investigated. In the brine shrimp lethality assay, the 50% fatal concentrations (LC50) were 34.10 μg/mL (silibinin) and 91.33 μg/mL (naringenin) compared to the standard potassium dichromate (13.15 μg/mL). The acute toxicity investigation found no mortality or visible abnormalities in the silibinin- and naringenin-treated groups (LC50 > 100 mg/L). The altered scototaxis behaviour in LDPT caused by BPA was reversed by co-supplementation with silibinin and naringenin, as shown by decreases in the number of transitions to the light zone and the duration spent in the light zone. Our findings point to BPA’s neurotoxic potential in causing altered scototaxis and bottom-dwelling behaviour in zebrafish, as well as the usage of silibinin and naringenin as potential neuroprotectants. 相似文献
374.
Jyoti Mehta Kumar Utkarsh Shivkanya Fuloria Tejpal Singh Mahendran Sekar Deeksha Salaria Rajan Rolta M. Yasmin Begum Siew Hua Gan Nur Najihah Izzati Mat Rani Kumarappan Chidambaram Vetriselvan Subramaniyan Kathiresan V. Sathasivam Pei Teng Lum Subasini Uthirapathy Olatomide A. Fadare Oladoja Awofisayo Neeraj Kumar Fuloria 《Molecules (Basel, Switzerland)》2022,27(15)
Urinary tract infections (UTIs) are becoming more common, requiring extensive protection from antimicrobials. The global expansion of multi-drug resistance uropathogens in the past decade emphasizes the necessity of newer antibiotic treatments and prevention strategies for UTIs. Medicinal plants have wide therapeutic applications in both the prevention and management of many ailments. Bacopa monnieri is a medicinal plant that is found in the warmer and wetlands regions of the world. It has been used in Ayurvedic systems for centuries. The present study aimed to investigate the antibacterial potential of the extract of B. monnieri leaves and its bioactive molecules against UTIs that are caused by Klebsiella pneumoniae and Proteus mirabilis. This in vitro experimental study was conducted by an agar well diffusion method to evaluate the antimicrobial effect of 80% methanol, 96% ethanol, and aqueous extracts of B. monnieri leaves on uropathogens. Then, further screening of their phytochemicals was carried out using standard methods. To validate the bioactive molecules and the microbe interactions, AutoDock Vina software was used for molecular docking with the Klebsiella pneumoniae fosfomycin resistance protein (5WEW) and the Zn-dependent receptor-binding domain of Proteus mirabilis MR/P fimbrial adhesin MrpH (6Y4F). Toxicity prediction and drug likeness were predicted using ProTox-II and Molinspiration, respectively. A molecular dynamics (MD) simulation was carried out to study the protein ligand complexes. The methanolic leaves extract of B. monnieri revealed a 22.3 mm ± 0.6 mm to 25.0 mm ± 0.5 mm inhibition zone, while ethanolic extract seemed to produce 19.3 mm ± 0.8 mm to 23.0 mm ± 0.4 mm inhibition zones against K. pneumoniae with the use of increasing concentrations. In the case of P. mirabilis activity, the methanolic extracts showed a 21.0 mm ± 0.8 mm to 24.0 mm ± 0.6 mm zone of inhibition and the ethanol extract produced a 17.0 mm ± 0.9 mm to 23.0 mm ± 0.7 mm inhibition zone with increasing concentrations. Carbohydrates, flavonoids, saponin, phenolic, and terpenoid were common phytoconstituents identified in B. monnieri extracts. Oroxindin showed the best interactions with the binding energies with 5WEW and 6Y4F, −7.5 kcal/mol and −7.4 kcal/mol, respectively. Oroxindin, a bioactive molecule, followed Lipinski’s rule of five and exhibited stability in the MD simulation. The overall results suggest that Oroxindin from B. monnieri can be a potent inhibitor for the effective killing of K. pneumoniae and P. mirabilis. Additionally, its safety has been established, indicating its potential for future drug discovery and development in the treatment for UTIs. 相似文献
375.
J. Daisy Vimala Rani S. Kamatchi A. Dhathathreyan 《Journal of colloid and interface science》2010,341(1):48-52
Stable lyophilisomes of fibrinogen at pH 7.5 have been prepared by the method of a rapid freezing–heating and annealing sequence. Reduction of the lyophilisomes of the nickel–fibrinogen complex coated on solid substrates and subsequent heating showed formation of nickel hydroxide and finally nickel oxide. Ultraviolet–visible spectroscopy has been used to monitor the thin films of pure fibrinogen microcapsules, as well as the subsequent nucleation and growth of nanoparticles within the supramolecular structure. Transmission electron microscopy showed initially a thread-like structure which disappeared on continued heating, resulting in nanoparticles ranging from 10 to 50 nm. Particle-size distribution of product was analyzed by using X-ray diffraction (XRD), transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED), and Brunauer–Emmett–Teller (BET) N2 adsorption. The results suggest that the NiO particles have a body-centered cubic structure and are well dispersed. The particle-size distribution ranges from 10 to 50 nm with an average particle size about 28 nm, and the specific surface area is 34 m2/g. Magnetic study carried out on the prepared nanoparticles showed a ferromagnetic behavior. 相似文献
376.
A. Usha Rani N. Sundaraganesan M. Kurt M. Cinar M. Karabacak 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(5):1523-1529
In this work, the vibrational spectral analysis was carried out by using FT-IR and FT-Raman spectroscopy in the range 400–4000 and 50–3500 cm?1 respectively, for the title molecule. The structural and spectroscopic data of the molecule in the ground state were calculated by using density functional method using 6-311++G(d,p) basis set. The vibrational frequencies were calculated and scaled values were compared with experimental FT-IR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The complete assignments of all the vibrational mode were performed on the basis of the total energy distributions (TED). 13C and 1H NMR chemical shifts results were given and are in agreement with the corresponding experimental values. The theoretically constructed FT-IR and FT-Raman spectra exactly coincides with experimental one. 相似文献
377.
Puri Usha Rani P. Muralidhar Reddy Kanne Shanker Vadde Ravinder 《Transition Metal Chemistry》2008,33(2):153-160
Organometallics of the type [Rh(COD)(L)Cl] (where, L = carboxyl/formyl/pyridyl tertiary phosphines) have been synthesized
by treating the precursor [Rh(COD)Cl]2 with substituted tertiary phosphines. [Rh(COD)(Ph2P-2-C6H4COO)] and [Rh(COD)(Ph2P-CH2COO)] were synthesized by halide abstraction from the precursor [Rh(COD)Cl]2 in the presence of AgPF6 in tetrahydrofuran by involving 2-carboxy phenyl/carboxy methyl group of tertiary phosphines in coordination as bidentate
ligands. Similarly, the cationic compounds of the type [Rh(COD)L2]PF6 were also synthesized by treating [Rh(COD)Cl]2 in the presence of AgPF6. All these compounds were characterized by elemental analysis, conductance measurements, IR, 1H, 13C, 31P NMR, mass, and electronic spectral studies. [Rh(COD)(Ph2-P-2-C6H4COOH)Cl] and [Rh(COD)(Ph2-P-2-C6H4COO)] were studied on the catalytic reduction reactions of 2-nitroanisole, 3-nitro anisole, 4-nitroanisole, 2-nitrobenzoicacid,
3-nitrobenzoicacid, 4-nitrobenzoicacid under mild conditions and [Rh(COD)(Ph2-P-2-C6H4COO)] was found to be more efficient than [Rh(COD)(Ph2-P-2-C6H4COOH)Cl].
This article is dedicated to Dr. D. R. M Walton, who successfully completed his tenure as Editor-in-Chief, Transition Metal
Chemistry. 相似文献
378.
Chandra S Raizada S Rani S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(2):720-724
Palladium(II) and platinum(II) complexes having the general composition [M(L)] X2 (where M=Pd(II) and Pt(II), L=3,4,12,13-tetraphenyl-2,5,11,14,19,20-hexaaza tricyclo [13.3.1.1.(6-10)] cosa-1(19), 2,4,6,8,10,(20),11,13,15,17-decaene (L1); 3,4,13,14-tetraphenyl-2,5,12,15-tetraaza tricyclo [11,0,0,(6-11)] cosa-1(16),2,4,7,9,6(11),12,14,17, 19-decaene (L2); 2,3,8,9-tetraphenyl-1,4,7,10-tetraaza cyclododeca-1,3,7,9-tetraene (L3) and X=Cl(-)) have been synthesized. The ligands were characterized on the basis of elemental analyses, IR, 1H NMR and EI mass spectral studies while that of the complexes were characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, and electronic spectral techniques. All the complexes were found to be diamagnetic. The structures consist of monomeric units in which the Pd(II) and Pt(II) atoms exhibit square planar geometry. 相似文献
379.
380.
In this paper, the effect of angle inclination at the interface of a viscous fluid and thermoelastic micropolar honeycomb solid due to inclined load is investigated. The inclined load is assumed to be a linear combination of normal load and tangential load. Laplace transform with respect to time variable and Fourier transform with respect to space variable are applied to solve the problem. Expressions of stresses, temperature distribution, and pressures in the transformed domain are obtained by introducing potential functions. The numerical inversion technique is used to obtain the solution in the physical domain. The frequency domain expressions for steady state are also obtained with appropriate change of variables. Graphic representations due to the response of different sources and changes of angle inclination are shown. Some particular cases are also discussed. 相似文献