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81.
Sahebeh Nikahd Reza Babadi Aghakhanpour S. Masoud Nabavizadeh Fatemeh Niroomand Hosseini S. Jafar Hoseini Arno Pfitzner Mozhgan Samandar Sangari 《应用有机金属化学》2019,33(11)
A new series of cycloplatinated (II) complexes with general formulas of [Pt (bhq)(N3)(P)] [bhq = deprotonated 7,8‐benzo[h]quinoline, P = triphenyl phosphine (PPh3) and methyldiphenyl phosphine], [Pt (bhq)(P^P)]N3 [P^P = 1,1‐bis (diphenylphosphino)methane (dppm) and 1,2‐bis (diphenylphosphino)ethane] and [Pt2(bhq)2(μ‐P^P)(N3)2] [P^P = dppm and 1,2‐bis (diphenylphosphino)acetylene] is reported in this investigation. A combination of azide (N3?) and phosphine (monodentate and bidentate) was used as ancillary ligands to study their influences on the chromophoric cyclometalated ligand. All complexes were characterized by nuclear magnetic resonance spectroscopy. To confirm the presence of the N3? ligand directly connected to the platinum center, complex [Pt (bhq)(N3)(PPh3)] was further characterized by single‐crystal X‐ray crystallography. The photophysical properties of the new products were studied by UV–Vis spectroscopy in CH2Cl2 and photoluminescence spectroscopy in solid state (298 or 77 K) and in solution (77 K). Using density functional theory calculations, it was proved that, in addition to intraligand charge‐transfer (ILCT) and metal‐to‐ligand charge‐transfer (MLCT) transitions, the L′LCT (L′ = N3, L = C^N) electronic transition has a remarkable contribution in low energy bands of the absorption spectra (for complexes [Pt (bhq)(N3)(P)] and [Pt2(bhq)2(μ‐P^P)(N3)2]). It is indicative of the determining role of the N3? ligand in electronic transitions of these complexes, specifically in the low energy region. In this regard, the photoluminescence studies indicated that the emissions in such complexes originate from a mixed 3ILCT/3MLCT (intramolecular) and also from aggregations (intermolecular). 相似文献
82.
In this work, using density functional theory, the kinetic effects of the substitution of a t‐butyl group and\or the incorporation of an oxygen atom, and both, at the aziridine ring moiety were investigated for N‐inversion in N‐phenylaziridine. Then, for N‐inversion in 3‐t‐butyl‐N‐phenyloxaziridine, the kinetic Hammett substituent effects were studied using the different para‐substituted groups on the N‐phenyl ring moiety. The natural bond orbital (NBO) study was the last case in this work. The calculations were performed in the gas phase and solution (in carbon tetrachloride and dichloromethane). The incorporation of an oxygen atom in the aziridine ring strongly weakens the N‐inversion process. In addition, while both t‐butyl substituent and solvent slightly reinforce the N‐inversion of N‐phenyloxaziridine, in N‐phenylaziridine, they decrease the N‐inversion rate to some extent. In both phases, more pronounced in solution and especially in dichloromethane, and in agreement with the NBO results, the electron‐withdrawing groups on para position of the N‐phenyl ring strongly increase the rate of N‐inversion of 3‐t‐butyl‐N‐phenyloxaziridine molecule. 相似文献
83.
Nano-Mg- [4-methoxy phenylsalicylaldiminemethylpyranopyrazole]Cl2 (nano-[Mg-4MSMP]Cl2) as a nano-Schiff base complex was prepared and fully characterized using some various techniques including fourier transform infrared spectroscopy (FT-IR), energy-dispersive x-ray spectroscopy (EDS), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), differential thermal gravimetric analysis (DTA), mass spectroscopy (MS) and scanning electron microscopy (SEM). Nano-[Mg-4MSMP]Cl2 was successfully used as an efficient catalyst for the preparation of some 1-(α-aminoalkyl) -2 -naphthols. 相似文献
84.
Tungstate supported mesoporous silica SBA‐15 with imidazolium framework as a hybrid nanocatalyst for selective oxidation of sulfides in the presence of hydrogen peroxide
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Alireza Sedrpoushan Fereshteh Hosseini‐Eshbala Farajollah Mohanazadeh Masoud Heydari 《应用有机金属化学》2018,32(2)
In this work, a new heterogeneous catalyst (SBA‐15/Im/WO42?) was prepared, and then its performance in the oxidation of organic sulfides was studied (using 30% H2O2 as green oxidant under neutral reaction conditions). This organic–inorganic hybrid mesoporous material was characterized by various techniques, such as FT‐IR, inductively coupled plasma, X‐ray powder diffraction, high‐resolution‐transmission electron microscopy, N2 adsorption–desorption and thermogravimetric analysis. The catalyst was also applied to the selective oxidation of various sulfides. The hybrid catalyst was easily recovered, and was very stable and retained good activity for at least five successive runs without any additional activation. Moreover, there was no remarkable decrease in the activity and selectivity of the catalyst. The products could be easily isolated by just removing the solvent after filtering the catalyst. The yields of the catalytic productions through this catalyst were in the range from 75% to 97%. 相似文献
85.
HKUST‐1‐Cu synthesized in the presence and absence of P‐123 trough solvotermal method. After characterization using some different microscopic and spectroscopic techniques such as XRD, FT‐IR, SEM, ICP, BET and TEM its catalytic activity was investigated in the oxidative coupling of benzyl alcohol, benzaldhyde, benzoic acid, styrene and phenyl acetylene with N,N‐dialkylformamides for the preparation of N,N‐dimethylformamides. Different derivatives of tertiary amides were synthesized in moderate to good yields in the presence of just ~0.28 mol% of this catalytic system. Reusability of the synthesized catalysts was examined and catalysts were reusable for 8 times without significant decrease in optimized conditions. 相似文献
86.
Ghasem Marandi Niloufar Akbarzadeh Torbati Reza Heydari Nourallah Hazeri Sayyed Mostafa Habibi-Khorassani Malek Taher Maghsoodlou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1450-1461
A series of diverse NH- and CH-acids are used for a one-pot synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds by trapping of the zwitterionic intermediate from the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates under solvent-free conditions. The structural geometry for one of the products was confirmed by single crystal X-ray diffraction analysis. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
87.
Nicholas A. D. Burke M. A. Jafar Mazumder Mark Hanna Harald D. H. Stöver 《Journal of polymer science. Part A, Polymer chemistry》2007,45(17):4129-4143
Polyelectrolyte complexes between poly(methacrylic acid, sodium salt) and poly(diallyldimethylammonium chloride) (PDADMAC) or poly[2‐(methacryloyloxyethyl)trimethylammonium chloride] (PMOETAC) form gels, liquid phases, or soluble complexes depending on charge ratio, total polymer loading, polymer molecular weight, and ionic strength. Increasing the ionic strength of the medium led most polyelectrolyte pairs to transition from gel through liquid complexes (complex coacervate) to soluble complexes. These transitions shift to higher ionic strengths for higher molecular weight polymers, as well as for PMOETAC compared to PDADMAC. The complex phases swelled with increasing polymer loading, ultimately merging with the supernatant phase at a critical polymer loading. The isolated liquid complex phases below and above this critical loading were temperature‐sensitive, showing cloud points followed by macroscopic phase separation upon heating. Incorporating 5 mol % lauryl methacrylate into the polyanion led to increased complex yield with PDADMAC, and increased resistance to ionic strength. In contrast, incorporating 30 mol % of oligo(ethylene glycol) methacrylate into the polyanion led to decreased complex yield, and to lower resistance to ionic strength. Two polyelectrolyte systems that produced liquid complexes were used to encapsulate hydrophobic oils, and in one case were used to demonstrate the feasibility of crosslinking the resulting capsule walls. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4129–4143, 2007 相似文献
88.
Peykani Pejman Hosseinzadeh Lotfi Farhad Sadjadi Seyed Jafar Ebrahimnejad Ali Mohammadi Emran 《Fuzzy Optimization and Decision Making》2022,21(2):197-261
Fuzzy Optimization and Decision Making - Fuzzy data envelopment analysis (FDEA) is one of the most applicable approaches for performance assessment of peer decision making units under ambiguity... 相似文献
89.
Nadi Mohammad Taghi Zafarani Jafar 《Journal of Optimization Theory and Applications》2022,193(1):158-179
Journal of Optimization Theory and Applications - We present the second-order point-based (necessary and sufficient) optimality conditions for nonlinear programming with continuously differentiable... 相似文献
90.
Mohammad Hosein Sayahi Seyyed Jafar Saghanezhad Saeed Bahadorikhalili Mohammad Mahdavi 《应用有机金属化学》2019,33(1)
A novel methodology is presented for the synthesis of 3‐substituted 2‐thioxo‐2,3‐dihydroquinazolin‐4(1H)‐one derivatives based on an efficient tandem multicomponent reaction using copper bromide as catalyst. This methodology is based on the multicomponent one‐pot reaction of methyl 2‐bromobenzoate, phenylisothiocyanate derivatives and sodium azide in the presence of copper bromide and l ‐proline under basic conditions. To show the generality of the method, various phenylisothiocyanates bearing electron‐donating or electron‐withdrawing functionalities were used and the desired products were obtained in high isolated yields. 相似文献