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101.
New formulations capable to enhance piroxicam (PRX) water solubility and at the same time to control and adjust its release have been developed. For this purpose, two methods have been used and combined to achieve this goal, namely complexation and microencapsulation by O/W emulsion solvent evaporation. In order to modify the drug release, first, microparticles composed of pure PRX and ethylcellulose (EC) or mixtures of EC and hydroxypropylmethylcellulose (HPMC) were prepared, and then, other micropaticles containing the β-cyclodextrin/piroxicam (β-CD/PRX) complex obtained by the solvent evaporation technique and EC or a mixture of EC and HPMC were produced and tested. These formulations were characterized by FT-IR, XRD, optical microscopy, and SEM methods. Drug dissolution tests were carried out in acidic media at pH = 1.2 and 37°C. Depending on the microparticles composition, their size (d10) ranged between 49 μ.m and 121 μ.m and PRXloaded varied from 10.8 % to 27.7 %. The effect of complexation and HPMC polymer on the drug release was investigated; the results demonstrated that the Higuchi’s release constant significantly increased when using the EC/HPMC mixture as a matrix with pure PRX or only EC as a matrix with the β-CD/PRX complex. The results are remarkably promising since the combination of these processes provided new SD-CR formulations of piroxicam which enabled simultaneous enhancement and control of its release from the carriers. 相似文献
102.
Kıvanç Ersoy 《Archiv der Mathematik》2016,106(5):401-407
In this paper, we prove that a finite group with a splitting automorphism of odd order is solvable. By using this result, we prove that a locally finite group with a splitting automorphism of odd order is locally solvable. 相似文献
103.
Mawardi Bahri 《Advances in Applied Clifford Algebras》2016,26(2):513-527
This paper proposes a new uncertainty principle for the two-sided quaternion Fourier transform. This uncertainty principle describes that the spread of a quaternion-valued function and its two-sided quaternion Fourier transform (QFT) are inversely proportional. We obtain a tighter lower bound about the product of the spread of quaternion signal in the QFT domain. As a consequence, we show that the quaternionic Gabor filters minimize the uncertainty. 相似文献
104.
O. Ersoy 《BIT Numerical Mathematics》1985,25(3):541-556
The trigonometric functions sin(2n/N) and cos(2n/N) are transformed into a new set of basis functions using Möbius inversion of certain types of series. The new basis functions are number theoretic series. They are used to represent the real discrete Fourier transform (RDFT) in terms of 2 matrices of factorization. The first matrix, with elements 1, -1 and 0 is obtained by replacing cos(2k/N) and sin(2k/N) by (k/N + 1/4) and (k/N), where (x) is the bipolar rectangular wave function. The second matrix is block-diagonal where each block is a circular correlation and consists of the new basis functions. Some applications of the new representation are discussed. 相似文献
105.
Waste plastics are non-degradable constituents that can stay in the environment for centuries. Their large land space consumption is unsafe to humans and animals. Concomitantly, the continuous engineering of plastics, which causes depletion of petroleum, poses another problem since they are petroleum-based materials. Therefore, energy recovering trough pyrolysis is an innovative and sustainable solution since it can be practiced without liberating toxic gases into the atmosphere. The most commonly used plastics, such as HDPE, LDPE (high- and low-density polyethylene), PP (polypropylene), PS (polystyrene), and, to some extent, PC (polycarbonate), PVC (polyvinyl chloride), and PET (polyethylene terephthalate), are used for fuel oil recovery through this process. The oils which are generated from the wastes showed caloric values almost comparable with conventional fuels. The main aim of the present review is to highlight and summarize the trends of thermal and catalytic pyrolysis of waste plastic into valuable fuel products through manipulating the operational parameters that influence the quality or quantity of the recovered results. The properties and product distribution of the pyrolytic fuels and the depolymerization reaction mechanisms of each plastic and their byproduct composition are also discussed. 相似文献
106.
Yasemin Daşdemir Kurt Bahri Ülküseven Sadık Güner Yüksel Köseoğlu 《Transition Metal Chemistry》2007,32(4):494-500
The S-methyl thiosemicarbazone derivatives of 2-amino-5-chlorobenzophenone and 2-(2-hydroxybenzylidene)amino-5-chlorobenzophenone
(LI and LII) and their copper(II) and palladium(II) chelates were synthesized. The solid compounds, [Cu(LI)Cl]Cl · 2H2O, [Cu(LII)Cl]Cl · H2O, [Pd(LI)Cl]Cl, and [Pd(LII)Cl2], were characterized by elemental analysis, thermogravimetric measurements, electronic, i.r., 1H-n.m.r. and e.p.r. spectroscopy. The ligand behavior of the LI and LII explained by means of spectroscopic data. The experimental X-band e.p.r. spectra recorded from two different copper(II) ion
coordinated powder complexes have characteristic line shapes that exhibit the axial symmetry around the paramagnetic ions.
The theoretically well fitted spectra prove this case too. The absence of hyperfine signals has been attributed to the strong
covalency effects of copper electrons with neighbouring N atoms. Orbital energy levels for magnetic electrons were determined
from Spin Hamiltonian parameters. The anisotropic Lande splitting factors were specified in an order of
and this case indicates that the unpaired electrons are located mainly in the
orbital. 相似文献
107.
İrfan Kızılcıklı Songül Eğlence Ali Gelir Bahri Ülküseven 《Transition Metal Chemistry》2008,33(6):775-779
New dioxomolybdenum(VI) complexes were prepared by reacting S-methyl/allyl-4-phenyl-thiosemicarbazones of 2-hydroxy-1-naphthaldehyde (L
1
H2 and L
2
H2) and [MoO2(acac)2] in methyl, ethyl and propylalcohols. In the complexes the doubly deprotonated ligands are coordinated to molybdenum as tridentate
ONN-donors through phenolic-oxygen, azomethine- and thioamide-nitrogen. The solid complexes of general formula [MoO2L(ROH)] which contain an alcohol (ROH) as second ligand were characterized by physico-chemical and spectroscopic methods.
The fluorescence emission intensities of the compounds were recorded in chloroform, and the intensity changes were evaluated
depending on chelation and time. The structure of the S-allyl-4-phenyl-thiosemicarbazone complex has been determined by the
single crystal X-ray diffraction method.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
108.
Ibrahim Erol Derya Nimet Devrim Hakan Ciftci Bahri Ersoy I. Hakkı Cigerci 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(7):434-445
A new methacrylate monomer 2-(4-nitrophenyl)-2-oxoethyl-2-methacrylate (NFM) was synthesized and its radical copolymerization with glycidyl methacrylate (GMA) was studied in 1,4-dioxane solution at 65°C using 2,2′-azobisisobutyronitrile as an initiator. The synthesized monomer and copolymers were characterized by FTIR, 1H and 13C-NMR spectroscopy. The analysis of reactivity ratios revealed that NFM is less reactive than GMA, and copolymers formed are statistically in nature. Thermogravimetric analysis of the polymers reveals that the thermal stability of the copolymers increases with an increasing in the mole fraction of NFM in the copolymers. Glass transition temperatures of the copolymers decreased with an increasing of NFM molar fraction in copolymers. In addition, according to the results obtained from the contact angle and zeta potential measurements the hydrophobic character of the polymer decreases (it means surface free energy increases) and its zeta potential becomes more negative with increase of NFM ratio in the copolymer. Polymers with carbonyl functional groups have been particularly interesting because of their use as photoresists. 相似文献
109.
F. Golay M. Ersoy L. Yushchenko D. Sous 《International Journal of Computational Fluid Dynamics》2015,29(1):67-81
In this work, we present a fast and parallel finite volume scheme on unstructured meshes applied to complex fluid flow. The mathematical model is based on a three-dimensional compressible low Mach two-phase flows model, combined with a linearised ‘artificial pressure’ law. This hyperbolic system of conservation laws allows an explicit scheme, improved by a block-based adaptive mesh refinement scheme. Following a previous one-dimensional work, the useful numerical density of entropy production is used as mesh refinement criterion. Moreover, the computational time is preserved using a local time-stepping method. Finally, we show through several test cases the efficiency of the present scheme on two- and three-dimensional dam-break problems over an obstacle. 相似文献
110.
Let A be an f-algebra with unit and L,M be two f-modules on A. We define f-orthomorphisms from L into M and show that these operators coincide with the f-linear operators whenever M is topologically full with respect to A. We show that f-orthomorphisms enjoy many of the properties of orthomorphisms. 相似文献