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91.
An hydroxyl substituted hexa(phenoxy)cyclotriphosphazene (3) is reacted with silicon phthalocyanine (4), SiPc(Cl)2, to give an axially-disubstituted phenoxycyclotriphosphazenyl silicon phthalocyanine (5). In this study, an axially phosphazene substituted phthalocyanine complex synthesized at the first time. Newly synthesized silicon phthalocyanine complex has been fully characterized by elemental analysis, ESI mass spectrometry, FT-IR, 1H, 13C and 31P NMR spectroscopy. Photophysical (fluorescence quantum yield and lifetime) and photochemical (singlet oxygen generation and photodegradation quantum yield) properties of complex 5 are reported in DMSO. The fluorescence quenching behaviour of this complex by 1,4-benzoquinone (BQ) is also reported in DMSO. 相似文献
92.
Gönül Yenilmez Çiftçi Hakan Dal Esra Tanrıverdi Eçik Tuncer Hökelek Adem Kılıç Elif Şenkuytu 《Polyhedron》2010
In this study, the crystal structures of the dispiroansa spermine derivatives of cyclotriphosphazene are characterised for the first time. The reaction of spiro-, gem-disubstituted cyclotriphosphazene derivatives, N3P3Cl4R2 [R = NHPh, (HN(CH2)3NH)0.5, (OCH2C(CH3)2CH2O)0.5], (1–3), with spermine (4), in aprotic solvents such as CH2Cl2 results in a series of dispirobino spermine derivatives of cyclotriphosphazene (5a, 6a, 7), namely spermine bridged compounds. Whereas, in protic solvents such as CHCl3 give, dispiroansa derivatives (8–10) namely tetracyclic cyclotriphosphazene. The new series of dispirobino and dispiroansa spermine derivatives of cyclotriphosphazene (5a, 6a, 7–10) have been characterised by elemental analysis, mass spectrometry, X-ray (for 5a, 8, 10) and 1H, 31P NMR spectroscopies. 相似文献
93.
Compton scattering method has been used as a possible tool in the study of the properties of soil for agricultural purposes. In this study, the soil water is determined by using Compton scattering method. The soil sample was collected from Erzurum and a 2 × 2 in. NaI (Tl) scintillation detector measured Compton scattered radiation from the soil sample. The radioactive source used in the experiment was a 133Ba. The soil samples were irrigated by adding known quantities of water and a standard curve was constructed with the amount of water added versus Compton scattering intensity. It was observed that Compton scattering method in measurement of the soil water has advantages such as practical, inexpensive, non‐destructive and fast analysis. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
94.
Crystal structure prediction from first principles is still one of the most challenging and interesting issue in condensed matter science. we explored the potential energy surface of NaBH4 by a combined ab-initio approach, based on global structure optimizations and quantum chemistry. In particular, we used simulated annealing (SA) and density functional theory (DFT) calculations. The methodology enabled the identification of several local minima, of which the global minimum corresponded to the tetragonal ground-state structure (P42/nmc), and the prediction of higher energy stable structures, among them a monoclinic (Pm) one was identified to be 22.75 kJ/mol above the ground-state at T=298 K. In between, orthorhombic and cubic structures were recovered, in particular those with Pnma and symmetries. 相似文献
95.
Mesut Gorur Faruk Yilmaz Adem Kilic Ali Demirci Yusuf Ozdemir Arif Kosemen Sait Eren San 《Journal of polymer science. Part A, Polymer chemistry》2010,48(16):3668-3682
Hexa‐armed and thiophene (Thi) end‐capped poly(ε‐caprolactone) star polymer (N3P3‐(PCL‐Thi)6), containing cyclotriphosphazene core, was prepared in a four‐step reaction sequence. Ring‐opening polymerization (ROP) and “click chemistry” techniques were employed in the first and final steps, respectively. Hexa‐armed PCL star polymer (N3P3‐(PCL‐OH)6) was successfully synthesized via ROP of ε‐caprolactone (ε‐CL) by using hekzakis(p‐(hydroxymethyl)phenoxy) cyclotriphosphazene as the multisite initiator and tin(II) 2‐ethylhexanoate (Sn(Oct2)) as the catalyst in bulk at 115 °C. Further modifications of the N3P3‐(PCL‐OH)6 were accomplished by derivatization of the hydroxyl‐functional chain ends. The obtained N3P3‐(PCL‐OH)6 was then reacted with 2‐bromo‐2‐methylpropanoyl bromide, and this led to a star polymer with bromide end groups, N3P3‐(PCL‐Br)6. In the third step, N3P3‐(PCL‐Br)6 was azidified with sodium azide (NaN3) in DMF affording N3P3‐(PCL‐N3)6. Conversion of the azide chain end groups into Thi was quantitatively accomplished via the “click reaction” between N3P3‐(PCL‐N3)6 and prop‐2‐yn‐1‐yl 3‐thienyl acetate in the final step. Subsequently, the star polymer with six Thi chain ends (N3P3‐(PCL‐Thi)6) was employed in electrochemical copolymerization with both pyrrole and Thi. Electrochromic properties and electrochromic device application of N3P3‐(PCL‐Thi)6/PThi were also investigated. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3668–3682, 2010 相似文献
96.
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98.
In this paper we prove that a finite group G with Cohen-Macaulay mod p cohomology will have non-trivial undetectable elements in if and only if G is a p-group such that every element of order p in G is central. Applications and examples are also provided.
Received: April 18, 1996 相似文献
99.
Exact solutions of nonlinear time fractional partial differential equations by sub‐equation method 下载免费PDF全文
Ahmet Bekir Esin Aksoy Adem C. Cevikel 《Mathematical Methods in the Applied Sciences》2015,38(13):2779-2784
In this article, the sub‐equation method is presented for finding the exact solutions of a nonlinear fractional partial differential equations. For this, the fractional complex transformation method has been used to convert fractional‐order partial differential equation to ordinary differential equation. The fractional derivatives are described in Jumarie's the modified Riemann–Liouville sense. We apply to this method for the nonlinear time fractional differential equations. With the aid of symbolic computation, a variety of exact solutions for them are obtained. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
100.
The term ionone is derived from “iona” (Greek for violet) which refers to the violet scent and “ketone” due to its structure. Ionones can either be chemically synthesized or endogenously produced via asymmetric cleavage of β-carotene by β-carotene oxygenase 2 (BCO2). We recently proposed a possible metabolic pathway for the conversion of α-and β-pinene into α-and β-ionone. The differences between BCO1 and BCO2 suggest a unique physiological role of BCO2; implying that β-ionone (one of BCO2 products) is involved in a prospective biological function. This review focuses on the effects of ionones and the postulated mechanisms or signaling cascades involved mediating these effects. β-Ionone, whether of an endogenous or exogenous origin possesses a range of pharmacological effects including anticancer, chemopreventive, cancer promoting, melanogenesis, anti-inflammatory and antimicrobial actions. β-Ionone mediates these effects via activation of olfactory receptor (OR51E2) and regulation of the activity or expression of cell cycle regulatory proteins, pro-apoptotic and anti-apoptotic proteins, HMG-CoA reductase and pro-inflammatory mediators. α-Ionone and β-ionone derivatives exhibit anti-inflammatory, antimicrobial and anticancer effects, however the corresponding structure activity relationships are still inconclusive. Overall, data demonstrates that ionone is a promising scaffold for cancer, inflammation and infectious disease research and thus is more than simply a violet’s fragrance. 相似文献