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排序方式: 共有137条查询结果,搜索用时 296 毫秒
41.
Jang DS Min HY Kim MS Han AR Windono T Jeohn GH Kang SS Lee SK Seo EK 《Chemical & pharmaceutical bulletin》2005,53(7):829-831
A new humulene sesquiterpene, 5-hydroxyzerumbone (5-hydroxy-2E,6E,9E-humulatrien-8-one) (1) and a known compound, zerumboneoxide (2) were isolated from the rhizomes of Zingiber zerumbet (Zingiberaceae), and found to inhibit lipopolysaccharide-induced nitric oxide production in murine macrophage RAW 264.7 cells with IC50 values of 14.1 and 23.5 microM, respectively, by bioassay-guided fractionation (positive control: N(omega)-monomethyl-L-arginine, IC50=21.3 microM). The structure of 1 was determined by spectroscopic methods including 1D and 2D-NMR. 相似文献
42.
An extract of the fruits of Trichosanthes tricuspidata collected in North Vietnam was found cytotoxic in KB cells. A bioassay-guided fractionation led to the isolation of a series of cucurbitacins of which two are new: tricuspidatin and 2-O-glucocucurbitacin J. Their isolation and structure determination are described. 相似文献
43.
Tri Q. LeRobert M. Oliver III Joel T. ArcariMark J. Mitton-Fry 《Tetrahedron letters》2012,53(42):5660-5662
An efficient, two-operation synthesis of the trail ant pheromone (±)-monomorine is reported. The synthesis features an aqueous Claisen-Schmidt condensation followed by the stereocontrolled installation of the three resident stereocenters in a single operation. 相似文献
44.
Pham Thi Nhat Trinh Nguyen Huu An Pham Ngoc An Mai Dinh Tri Cao Van Du Phan Nhat Minh 《Natural product research》2018,32(14):1648-1652
A new benzofuran derivative, pumiloside (1), together with seven known flavonoid glycosides, afzelin (2), astragalin (3), quercitrin (4), isoquercitrin (5), kaempferol 3-O-rutinoside (6), rutin (7) and kaempferol 3-O-sophoroside (8) were isolated from the leaves of Ficus pumila. Their structures were established by spectroscopic data and comparison with the literature values. 相似文献
45.
Mathematical Notes - Let $$R$$ be a commutative Noetherian ring with identity and $$I,J$$ two ideals of $$R.$$ We introduce the concept of $$(I,J)$$ -coweakly Laskerian module and study the... 相似文献
46.
Edy Tri Baskoro 《Discrete Mathematics》2005,294(3):275-277
For graphs G and H, the Ramsey numberR(G,H) is the smallest positive integer n such that every graph F of order n contains G or the complement of F contains H. For the path Pn and the wheel Wm, it is proved that R(Pn,Wm)=2n-1 if m is even, m?4, and n?(m/2)(m-2), and R(Pn,Wm)=3n-2 if m is odd, m?5, and n?(m-1/2)(m-3). 相似文献
47.
Synthesis of Some Novel Norbornene‐Fused Pyridazines as Potent Inhibitors of Carbonic Anhydrase and Acetylcholinesterase
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Ramazan Kocak Esra Turan Akın Pınar Kalın Oktay Talaz Nurullah Saracoglu Arif Dastan Ilhami Gülcin Serdar Durdagi 《Journal of heterocyclic chemistry》2016,53(6):2049-2056
The reaction of benzocyclic norbornene derivatives with tetrazines provided the 1,3‐dihydropyridazine derivatives as a single product. The dihydropyridazine derivatives have been dehydrogenated with phenyliodine bis(trifluoroacetate) to yield the corresponding pyridazines in a high yield. Two stable diazines, primary product of corresponding 1,4‐dihydropyridazine, were also isolated. Structures were then determined by 1H‐NMR, and 13C‐NMR beside to elemental analyses. The novel pyridazine derivatives ( 8 , 9 ) efficiently inhibited the cytosolic human carbonic anhydrase isoenzymes I and II (hCA I and II). In addition, these novel pyridazine derivatives ( 8 , 9 ) were evaluated for their in vitro acetylcholinesterase inhibitory activity. Ligand–receptor interactions are tested using molecular docking simulations. Obtained docking scores are in good agreement with in vitro results. 相似文献
48.
In this paper, we present analytical results for one-loop contributions to the decay processes \begin{document}$ H\rightarrow Z \nu_l\bar{\nu}_l $\end{document} ![]()
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(for \begin{document}$ l = e, \mu, \tau $\end{document} ![]()
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). The calculations are performed within the Standard Model framework in the 't Hooft-Veltman gauge. One-loop form factors are then written in terms of scalar one-loop functions in the standard notations of \begin{document}$ {\tt LoopTools}$\end{document} ![]()
![]()
. As a result, one-loop decay rates for the decay channels can be evaluated numerically by using the package. Furthermore, we analyze the signals of \begin{document}$ H\rightarrow Z \nu_l\bar{\nu}_l $\end{document} ![]()
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via the production processes \begin{document}$ e^-e^+ \rightarrow ZH^* \rightarrow Z (H^* \rightarrow Z \nu_l\bar{\nu}_l) $\end{document} ![]()
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, including the initial beam polarizations at future lepton colliders. The Standard Model backgrounds, such as the processes \begin{document}$ e^-e^+ \rightarrow \nu_l\bar{\nu}_l ZZ $\end{document} ![]()
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, are also examined in this study. Numerical results indicate that one-loop corrections make contributions of approximately 10% to the decay rates. These are sizeable contributions and should be taken into account at future colliders. We show that the signals \begin{document}$ H\rightarrow Z\nu_l\bar{\nu}_l $\end{document} ![]()
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are clearly visible at the center-of-mass energy \begin{document}$ \sqrt{s}=250 $\end{document} ![]()
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GeV and are difficult to probe in higher-energy regions owing to the dominant backgrounds. 相似文献
49.
50.
Md. Saiful Alam Agung Tri Wijayanta Koichi Nakaso Jun Fukai Koyo Norinaga Jun-ichiro Hayashi 《Combustion Theory and Modelling》2013,17(6):841-853
In the present paper, the authors study the primary reactions of coal volatiles and a detailed mechanism has been made for three different environments: thermal decomposition (pyrolysis), partial oxidation (O2) and O2/CO2 gasification in a plug flow reactor to analyze the combustion component. The computed results have similar trend for three different environments with the experimental data. A systematically reduced mechanism for O2/CO2 gasification has also been derived by examination of Rate of Production (ROP) analysis from the detailed mechanism (255 species and 1095 reactions). The reduced mechanism shows similar result and has been validated by comparing the calculated concentrations of H2, CH4, H2O, CO, CO2 and polycyclic aromatic hydrocarbon (PAH) with those of the detailed mechanism in a wide range of operating conditions. The authors also predicted the concentration profiles of H2, CO, CO2 and PAH at high temperature and high pressure. 相似文献