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41.
Let $$f : A \rightarrow B$$ be a ring homomorphism and J be an ideal of B. In this paper, we give a characterization of zero divisors of the amalgamation which is a generalization of Maimani’s and Yassemi’s work (see Maimani and Yassemi in J Pure Appl Algebra 212(1):168–174, 2008). Furthermore, we investigate the transfer of Prüfer domain concept to commutative rings with zero divisors in the amalgamation of A with B along J with respect to f (denoted by $$A\bowtie ^fJ),$$ introduced and studied by D’Anna et al. (Commutative algebra and its applications, Walter de Gruyter, Berlin, 2009, J Pure Appl Algebra 214:1633–1641, 2010). Our results recover well known results on duplications. The main applications constist in the construction of new original classes of Prüfer rings that are not Gaussian and Prüfer rings with weak global dimension strictly greater than 1. 相似文献
42.
Abdou Tchoukoua Ingrid Konga Simo Shota Uesugi Misa Ohno Ken-ichi Kimura 《Natural product research》2018,32(8):924-932
Two new triterpene saponins, albidosides H (1) and I (2), along with the three known saponins were isolated from the barks of Acacia albida. Their structures were elucidated on the basis of extensive 1D- and 2D-NMR studies and mass spectrometry. Albidosides H (1) and I (2) were assayed for their cytotoxicity against HeLa and HL60 cells using MTT method. 相似文献
43.
Boisselier E Diallo AK Salmon L Ruiz J Astruc D 《Chemical communications (Cambridge, England)》2008,(39):4819-4821
Gold nanoparticles (AuNPs) are synthesized and stabilized by new "clicked" dendrimers of generations zero to two (G(0)-G(2)) containing tri- and tetra-ethyleneglycol tethers; they are either encapsulated by G(1) (81 tethers) and G(2) (243 tethers) or stabilized without encapsulation by G(0) (27 tethers). 相似文献
44.
Pyrazolo[4,3‐d]pyrimidines, pyrazolo[4,3‐d]triazolino[4,3‐a]pyrimidines, 3‐(2‐thiazolyl)thiophenes, thiazolo[3,2‐a]pyridine and pyrazolo[1,5‐a]pyrimidines were synthesized from 2‐[4‐(3‐oxobenzo[f]‐2H‐chromen‐2‐yl)‐1,3‐thiazol‐2‐yl]ethanenitrile. The newly synthesized compounds were elucidated by elemental analysis, spectral data, chemical transformation and alternative synthesis route whenever possible. 相似文献
45.
Ahmed A. Mohamed Hanan E. Abdou Andrew Mayer John P. Fackler Jr. 《Journal of Cluster Science》2008,19(4):551-559
Abstract Attempts to remove the halide atoms from [Au2(hpp)2Cl2], 1, Hhpp = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine, with Ag(I) benzoate lead to the formation of the Au(I)–Ag(I) product, [(PhCOO)2Au4(hpp)4Ag2(PhCOO)4], 2. This material is stable to air and light at room temperature and shows a UV–vis spectrum in THF with absorbances at 575,
440, 345, and 273 nm. The mixed metal product crystallizes as green crystals in the monoclinic space group P21/n. The Au–Au distances of 2.4473(19) ? are the shortest gold–gold distances reported to date. The gold···silver distance is
3.344(3) ? and the silver···silver distance is 2.771(6) ?. This latter distance is short compared with the Ag···Ag distance
of 2.902(3) ? in the eight-membered silver benzoate dimer starting material. The Au(II) hpp and Ag(I) benzoate components
are linked by carboxylate groups and two gold-silver interactions. This result stands in structural contrast to terminal carboxylate
products observed with Au(II) ylides and amidinates wherein the carboxylate is not bridging to another metal atom.
Index Abstract Three equivalents of silver benzoate react with [Au2(hpp)2Cl2], 1, Hhpp = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine, to form the gold(II)-silver(I) product, 2, [(PhCOO)2Au4(hpp)4Ag2(PhCOO)4]. The gold–gold distance of 2.4473(19) ? is the shortest gold–gold distance reported to date. The gold–silver distance is
3.344(3) ? and the silver–silver distance is 2.771(6) ?.
Dedicated to the memory of F. Albert Cotton (1930–2007). 相似文献
46.
47.
Newab Hussain Giuseppe Marino Luigi Muglia Afrah A. N. Abdou 《Journal of Fixed Point Theory and Applications》2016,18(1):1-25
Let H be a Hilbert space, \({(W_n)_{n \in \mathbb{N}}}\) a suitable family of mappings, S a nonexpansive mapping and D a strongly monotone operator. We are interested in the strong convergence of the general schemein dependence of the coefficients \({(\alpha_{n})_{n \in \mathbb{N}}}\) and \({(\mu_{n})_{n \in \mathbb{N}}}\) .
相似文献
$$x_{n + 1} = \gamma x_{n} + (1 - \gamma)W_{n} (\alpha_{n}S_{x_{n}} + (1 - \alpha_{n})(I - \mu_{n}D)x_{n}),\quad \gamma \in [0, 1),$$
48.
A Convenient Synthesis of Some New 1,3,4‐Thiadiazoles,Thiazoles, Pyrazolo[1,5‐a]pyrimidines,Pyrazolo[5,1‐c]triazine,and Thieno[3,2‐d]pyrimidines Containing 5‐Bromobenzofuran Moiety 下载免费PDF全文
Abdou O. Abdelhamid Abdelgawad A. Fahmi Basma S. Baaiu 《Journal of heterocyclic chemistry》2016,53(4):1292-1303
1,3,4‐Thiadiazoles, pyrazolo[1,5‐a]pyrimidines, pyrazolo[5,1‐c]triazine, and thieno[3,2‐d]pyrimidines were synthesized from 1‐(5‐bromobenzofuran‐2‐yl)ethanone. The structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, chemical transformation, and alternative synthesis route whenever possible. 相似文献
49.
Useful Precursors for Synthesis of Some New Azolo[3,4‐d]pyridiazines,Azolo[1,5‐a]pyrimidines,Azolo[5,1‐c]triazines,Pyrazoles, and Benzo[b][l,4]diazepine 下载免费PDF全文
Abdou O. Abdelhamid Abdelgawad A. Fahmi Basma S. Baaiu 《Journal of heterocyclic chemistry》2016,53(6):1917-1927
Pyrazolo[3,4‐d]pyridazines, isoxazolo[3,4‐d]pyridazines, azolo[1,5‐a]pyrimidines, azolo[5,1‐c]triazines, pyrazoles, and benzo[b][l,4]diazepine were synthesized from the appropriate hydrazonoyl halides, hydroximoyl halides, heterocyclic amines, diazotized heterocyclic amines, arenediazonium chlorides, and o‐phenylenediamines with appropriate of sodium 3‐(5‐bromobenzofuran‐2‐yl)‐3‐oxoprop‐1‐en‐1‐olate or 1‐(5‐bromobenzofuran‐2‐yl)‐3‐(dimethylamino)prop‐2‐en‐1‐one. The newly synthesized compounds were elucidated by elemental analyses, spectral data, and alternative synthesis whenever possible. 相似文献
50.
Reem Ibrahim Al-Wabli Tamer Mostafa Mohamed Hafez Sakr Mohammed Abdou Khedr Adly Abdallah Selim Mohamed Abd El-Motaleb Abd El-Rahman Wafaa Abdou Zaghary 《Chemistry Central journal》2016,10(1):73
Background
One of the most popular techniques for cancer detection is the nuclear medicine technique. The present research focuses on Platelet-12-lipoxygenase (P-12-LOX) as a promising target for treating and radio-imaging tumor tissues. Curcumin was reported to inhibit this enzyme via binding to its active site.Results
A novel curcumin derivative was successfully synthesized and characterized with yield of 74%. It was radiolabeled with the diagnostic radioisotope technetium-99m with 84% radiochemical yield and in vitro stability up to 6 h. The biodistribution studies in tumor bearing mice confirmed the high affinity predicted by the docking results with a free binding energy value of (ΔG ?50.10 kcal/mol) and affinity (13.64 pki) showing high accumulation in solid tumor with target/non-target ratio >6.Conclusion
The newly synthesized curcumin derivative, as a result of a computational study on platelet-12 lipoxygenase, showed its excellent free binding energy (?G ?50.10 kcal/mol) and high affinity (13.64 pKi). It could be an excellent radio-imaging agent that targeting tumor cells via targeting of P-12-LOX.