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981.
Abdul Ghani Zuleen Delina Fasya Ab Rashid Ahmad Hazri Shaari Khozirah Chik Zamri 《Applied biochemistry and biotechnology》2019,189(2):690-708
Applied Biochemistry and Biotechnology - The present studies are to evaluate the ability of PB to induce weight loss and urine metabolite profile of Piper betle L. (PB) leaf extracts using... 相似文献
982.
Abdul‐Majid Wazwaz 《Mathematical Methods in the Applied Sciences》2012,35(7):845-856
In this paper, we present a reliable study on extensions of the Bratu problem with boundary conditions. The work rests mainly on Adomian decomposition method and Padé approximants. The study shows a variety of approximations, one for each extension. The work highlights the effect of the extensions on the structure of the approximate solutions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
983.
Akbar Ali Muhammad Khalid Saba Abid Javed Iqbal Muhammad Nawaz Tahir Abdul Rauf Raza Julio Zukerman-Schpector Marcio Weber Paixão 《应用有机金属化学》2020,34(3):e5399
The pyridine-based halogenated hydrazone derivatives (E)-N′-benzylidene-2-[(6″-chloroazin-2″-yl)oxy]acetohydrazide ( 6a ), (E)-N′-(3′-chlorobenzylidene)-2-[(6″-chloroazin-2″-yl)oxy]acetohydrazide ( 6b ) and (E)-N′-(3′-bromobenzylidene)-2-[(6″-chloroazin-2″-yl)oxy]acetohydrazide ( 6c ) have been obtained using 6-chloro-2-hydroxypyridine. The structure of the products ( 6a – c ) has been verified using X-ray crystallography and spectroscopic approaches. A single-crystal X-ray diffraction (SC-XRD) investigation showed that the structures are stabilized by intermolecular attractive forces. Additionally, density functional theory (DFT) has been adopted to explore the structural properties, vibrational spectra, noncovalent interactions and frontier molecular orbitals using the B3LYP/6-311 + G(d,p) level. The nonlinear optical properties of the title compounds were calculated using the CAM-B3LYP/6-311 + G(d,p) level. Frequency analysis confirmed the stability of the molecules, and an excellent correlation was observed between the DFT- and SC-XRD-based structural parameters. The SC-XRD analysis confirmed that the dimers of 6a , 6b and 6c are linked by hydrogen-bonding interactions. Natural bond orbital (NBO) analysis also reconfirmed the strength of intermolecular hydrogen-bonding and hyperconjugative interactions. NBO investigation was also utilized to analyze the atomic charges. Moreover, Fourier transform infrared and natural population analyses endorsed that there are significant N&bond;H⋅⋅⋅O&dbond;C hydrogen-bonding linkages in dimeric structures of the compounds. The hydrogen-bonding network and different sorts of hyperconjugative interactions are the main reasons for the stability of the products in the solid state. The highest occupied and lowest unoccupied molecular orbital energies and first-order nonlinear optical properties of these molecules are reported. The quantum chemical parameters were derived using frontier molecular orbital energies. 相似文献
984.
985.
Chloride and sulfate ions ingress behaviors in concrete are more complex and complicated processes than can be described by Fick's law of diffusion. A new approach based on two-dimensional correlation mapping (2D-CM) and particle-induced X-ray emission (PIXE) spectra was successfully applied to describe their transportation process. The use of hybrid 2D correlation enabled a fast comparison of ions ingress, whereas multiple perturbation correlation spectroscopy enabled the study of compositional factor affecting the ingress process. It was shown that by rearranging the same data in different ways, different techniques of 2D-CM could be applied and new information could be derived. The 2D-CM findings were in line with the classical PIXE analysis and consistent with the underlying physics of the experiments, which suggested that it will be a powerful and fast data analysis tool for PIXE spectra. 相似文献
986.
Dinh Hung Mac Abdul Sattar Srivari Chandrasekhar Jhillu Singh Yadav René Grée 《Tetrahedron》2012,68(43):8863-8868
A new versatile synthesis of 3-piperidones is described, starting from amino acids. It uses, as a key step, an iron carbonyl-mediated intramolecular tandem isomerization–aldolisation reaction. These new heterocycles appear as useful scaffolds for the total synthesis of various types of bioactive molecules. 相似文献
987.
988.
Alharbi F. F. Nisa Mehar Un Hassan Hassan Mohamed Ahmed Manzoor Sumaira Ahmad Zahoor Abid Abdul Ghafoor Aman Salma Ashiq Muhammad Naeem El-Nasser Karam S. Taha Taha Abdel Mohaymen 《Journal of Solid State Electrochemistry》2022,26(10):2171-2182
Journal of Solid State Electrochemistry - Metal sulfide and oxides have drawn interest as economical substitutes to noble metal catalysts due to their ability for oxygen evolution reaction (OER)... 相似文献
989.
Khan Ihtisham Wali Naeem Abdul Farooq Muhammad Mahmood Tahira Saeed Tooba Parveen Fouzia Malik Tabassum 《Catalysis Surveys from Asia》2022,26(3):144-160
Catalysis Surveys from Asia - The over-consumption of petroleum fuel due to the progressive increase in population, transportation, industrialization, modernization as well as improvement in the... 相似文献
990.
Basit Muhammad Abdul Tariq Zeeshan Zahid Saira Khan Sheheryar Siddiqui Farrukh Arsalan Khan Muhammad Farooq Ali Gohar Park Tae Joo 《Journal of Cluster Science》2022,33(6):2443-2454
Journal of Cluster Science - Successive ionic layer adsorption and reaction (SILAR) process has been diversely used for deposition of various metal chalcogenides. SnS is one of them. Owing to the... 相似文献