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41.
Zarife Sibel ahin Fatma Sevindi Hasan budak amil Ik 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(10):m314-m318
The title compounds, trans‐bis(trans‐cyclohexane‐1,2‐diamine)bis(6‐methyl‐2,2,4‐trioxo‐3,4‐dihydro‐1,2,3‐oxathiazin‐3‐ido)copper(II), [Cu(C4H4NO4S)2(C6H14N2)2], (I), and trans‐diaquabis(cyclohexane‐1,2‐diamine)zinc(II) 6‐methyl‐2,2,4‐trioxo‐3,4‐dihydro‐1,2,3‐oxathiazin‐3‐ide dihydrate, [Zn(C6H14N2)2(H2O)2](C4H4NO4S)2·2H2O, (II), are two‐dimensional hydrogen‐bonded supramolecular complexes. In (I), the CuII ion resides on a centre of symmetry in a neutral complex, in a tetragonally distorted octahedral coordination environment comprising four amine N atoms from cyclohexane‐1,2‐diamine ligands and two N atoms of two acesulfamate ligands. Intermolecular N—H...O and C—H...O hydrogen bonds produce R22(12) motif rings which lead to two‐dimensional polymeric networks. In contrast, the ZnII ion in (II) resides on a centre of symmetry in a complex dication with a less distorted octahedral coordination environment comprising four amine N atoms from cyclohexane‐1,2‐diamine ligands and two O atoms from aqua ligands. In (II), an extensive two‐dimensional network of N—H...O, O—H...O and C—H...O hydrogen bonds includes R21(6) and R44(16) motif rings. 相似文献
42.
In this paper we study the problem of optimization over an integer efficient set of a Multiple Objective Integer Linear Stochastic Programming problem. Once the problem is converted into a deterministic one by adapting the $2$ -levels recourse approach, a new pivoting technique is applied to generate an optimal efficient solution without having to enumerate all of them. This method combines both techniques, the L-shaped method and the combined method developed in Chaabane and Pirlot (J Ind Manag Optim 6:811–823, 2010). A detailed didactic example is given to illustrate different steps of our algorithm. 相似文献
43.
Urea dimethacrylates functionalized with bisphosphonate/bisphosphonic acid for improved dental materials 下载免费PDF全文
Melek Naz Guven Ece Akyol Fatma Demir Duman Havva Yagci Acar Ozlem Karahan Duygu Avci 《Journal of polymer science. Part A, Polymer chemistry》2017,55(19):3195-3204
Incorporation of bisphosphonate/bisphosphonic acid groups in dental monomer structures should increase interaction of these monomers with dental tissue as these groups have strong affinity for hydroxyapatite. Therefore, new urea dimethacrylates functionalized with bisphosphonate (1a, 1b) and bisphosphonic acid (2a, 2b) groups are synthesized and evaluated for dental applications. Monomers 1a and 1b are synthesized from 2‐isocyanatoethyl methacrylate (IEM) and two bisphosphonated amines (BPA1 and BPA2), prepared as reported elsewhere. Selective dealkylation of the bisphosphonate ester groups of 1a and 1b using trimethylsilyl bromide (TMSBr) gives monomers (2a and 2b) with bisphosphonic acid functionality. X‐ray diffractometer (XRD), Raman spectroscopy, and X‐ray photoelectron spectroscopy (XPS) analyses of monomer‐treated HAP particles show that 2a induces formation of stable monomer‐calcium salts, similar to 10‐methacryloyloxydecyl dihydrogen phosphate (MDP), with higher chemical interaction than 2b. The photopolymerization studies indicate good copolymerizability with commercial dental monomers. In vitro studies on NIH 3T3 mouse embryonic fibroblast cells have clearly shown that the tested monomers (1b and 2b) are not toxic according to the MTT standards. All these properties make these monomers suitable as biocompatible cross‐linkers/adhesives for dental applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3195–3204 相似文献
44.
45.
Utility of 4‐Benzylidene‐2‐phenyl‐5(4H)‐oxazolone in Synthesis of Triazine,Oxadiazole and Imidazole Derivatives of Anticipated Biological Activity 下载免费PDF全文
Ahmed S. A. Youssef Fatma A. El‐Mariah Fatma T. Abd‐Elmottaleb Heba E. Hashem 《Journal of heterocyclic chemistry》2015,52(5):1467-1473
Treatment of oxazolone 1 with hydrazine hydrate at room temperature gave the (Z)‐configurated isomer hydrazide (Z)‐ 3 (high yield). However, refluxing 1 with hydrazine hydrate yielded the (E)‐configurated isomer hydrazide (E)‐ 2 (low yield).The hydrazide derivative (Z)‐ 3 has been utilized as synthon for the synthesis of 1,2,4‐triazinone, imidazolone, and oxadiazole derivatives through appropriate routes. The thiosemicarbazide and semicarbazide derivatives are synthesized by different routes. The structures of the new compounds were established on the basis of IR, 1H‐NMR, mass spectral data, and elemental analysis. 相似文献
46.
Synthesis of New Pyrazoles via Cycloaddition Reactions of Nitrilimines with 2‐Cyclopentenone Derivatives 下载免费PDF全文
Fatma A. El‐Samahy 《Journal of heterocyclic chemistry》2015,52(2):597-602
Compounds 1,3,6,6a‐tetraphenyl‐1,6a‐dihydrocyclopenta[c]pyrazol‐4(3aH)‐ones ( 3 ), 1,3,3a,4‐tetraphenyl‐1,3a‐dihydrocyclopenta[c]pyrazol‐6‐ols ( 4 ) and 6‐hydroxy‐1,3,6,6a‐tetraphenyl‐1,5,6,6a‐tetrahydrocyclopenta[c]pyrazole‐4(aH)‐one ( 5 ) were synthesized by reaction of 3,4‐diphenyl‐4‐hydroxy‐2‐cyclopentenone ( 2a ) with nitrilimines, generated in situ by the action of triethylamine on the corresponding hydrazonyl chlorides 1 . 相似文献
47.
Trietazine was selectively separated from aqueous solution containing the competitor molecule cyanazine, which is similar in size and shape to the template molecule. Structural features of the molecularly imprinted column were figured out by SEM. The influence of the mobile‐phase composition, applied electrical field, and pH of the mobile phase on the recognition of trietazine by the imprinted monolithic polymer has been evaluated, and the imprint effect in the trietazine‐imprinted monolithic polymer was demonstrated by an imprinting factor. The optimized monolithic column resulted in separation of trietazine from a structurally related competitor molecule, cyanazine. In addition, fast separation was obtained within 6 min by applying higher electrical field, with the electrophoretic mobility of 2.97 × 10?8 m2V?1s?1 at pH 11.0. 相似文献
48.
In this study, radiocesium sorption on ceramic clay was investigated as a function of particle size and initial 137Cs concentration using a batch method. Ceramic clay samples taken from the Sö?üt(?nisar) clay deposit were composed of kaolinite, dickite and quartz. The equilibrium time and the liquid–solid ratio were determined as 60 min and 250 mL g?1, respectively. The distribution coefficients (K d) for variable liquid–solid ratio and the percentage adsorption (P Ad) were calculated. The values of K d and P Ad ranged from 483 to 3165 mL g?1 and 34–93%, respectively. The K d and P Ad values increased with increasing particle size, but decreased with increasing initial concentration. The sorption data were interpreted in terms of a Langmuir isotherm. The results indicated that the Sö?üt(?nhisar) ceramic clay has good sorption capacity for cesium. 相似文献
49.
Gönül Yenilmez Çiftçi Elif ?enkuytuEsra Tanr?verdi Eçik Adem K?l?çFatma Yuksel 《Polyhedron》2011,30(13):2227-2236
New 1,3-propanediaminocyclotriphosphazene derivatives (7-17) were synthesized from the reactions of spiro-1,3-propanediaminocyclotriphosphazene, N3P3Cl4[NH(CH2)3NH] (1) with the cyclopropanemethylamine (2), cyclohexylamine (3), pyrrolidine (4) cyclohexanol (5), cyclopropylmethanol (6). The structures of the novel compounds (7-17) were characterized by elemental analysis, mass spectrometry, 1H and 31P NMR spectroscopy. The molecular structures of 8, 12 and 13 were determined by X-ray crystallography. The structures of all these three compounds are in the monoclinic crystal system; compounds 8 and 12 have the P21/c space group while compound 13 has the P21/n space group. The ring conformation of the cyclotriphosphazene and other external rings were investigated based on the X-ray crystal structures. 相似文献
50.
In the last few years, researchers have an intense interest in the evolutionarily conserved signaling pathways which have crucial roles during embryonic development. The most intriguing factor of this interest is that malfunctioning of these signaling pathways (Hedgehog, Notch, Wnt etc.) leads to several human diseases, especially to cancer. This study deals with the β-catenin dependent branch of Wnt signaling and the Hedgehog signaling pathways which offer potential targeting points for cancer drug development. The identification of all proteins functioning in these signaling networks is crucial for the efforts of preventing tumor formation. Here, through integration of protein-protein interaction data and Gene Ontology annotations, Wnt/β-catenin and Hedgehog signaling networks consisting of proteins that have statistically high probability of being biologically related to these signaling pathways were reconstructed in Drosophila melanogaster. Next, by the structural network analyses, the crucial components functioning in these pathways were identified. The proteins Arm, Frizzled receptors (Fz and Fz2), Arr, Apc, Axn, Ci and Ptc were detected as the key proteins in these networks. Futhermore, the hub protein Mer having tumor suppressor function may be proposed as a putative drug target for cancer and deserves further investigation via experimental methods. Finally, the crosstalk analysis between the reconstructed networks reveals that these two signaling networks crosstalk to each other. 相似文献