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991.
《Analytical letters》2012,45(15):2369-2379
Metalloenzymes that carry a pterin-based molybdenum cofactor in their center catalyze numerous reactions in the human body and play a crucial role in its metabolism. Specifically, these enzymes promote redox reactions and oxygen transport in the body. Their absence may cause many problems leading to disability or even death in early childhood. Therefore, model compounds need to be synthesized and analyzed to investigate the reactivity, redox potential, and geometry of these cofactors. This study focused on electrode processes and determined the redox potentials of the new bis-(4-mercapto-5-(p-tolyl)-3H-1,2-dithiole-3-thione)-dioxomolybdenum complex by cyclic voltammetry. The 4-mercapto-5-(p-tolyl)-3H-1,2-dithiole-3-thione ligand underwent irreversible oxidation and reduction at thiol and thione functional groups. The new dioxomolybdenum complex showed a quasi-reversible two-stage electrode process. 相似文献
992.
《Analytical letters》2012,45(6):427-438
Abstract Mercury(II) ion accelerates the complex formation reaction of manganese(II) with α, β, γ δ-tetraphenylporohinesulfonate (TPPS). Mercury(II) concentrations as low as 10?8 mol dm?3 can be determined from the decrease in absorbance at 413 nm (Λmax of TPPS) at a fixed time after the initiation of the reaction of rnanganese(II) with TPPS. Sandell's sensitivity calculated from the calibration curve at 30 min after the start of the reaction is 3.8 × 10?2 ng cm?2. After the separation of metallic mercury by distillation at room temperature, the method is highly selective and is free from interference of most substances usually encountered. 相似文献
993.
《Journal of Coordination Chemistry》2012,65(5):865-874
Ni(II) complexes with 5,5′-bis(4-halogenphenyl)diazo-dipyrromethane have been synthesized and characterized by X-ray crystallography. All the complexes have similar crystal structures in which Ni(II) is square-planar by coordinating to two pyrrole and two azo nitrogen atoms. The azo-pyrroles of the ligands can be converted to the hydrazone tautomer after complexing nickel. Moreover, the C–H?···?Ni interaction played an important role in directing self-assembly of the complexes. The UV-Vis spectra of the complexes showed great difference with the metal complexes of pyrrol-2-imine. 相似文献
994.
《Journal of Coordination Chemistry》2012,65(7):1266-1277
Two new rhenium(I) complexes chelated by a substituted 2,2′-bipyridine with general formula Re(CO)3LCl, where L?=?6?-(2″-methoxyphenyl)-2,2′-bipyridine (L1 ) and 6?-(4″-diphenylaminophenyl)-2,2′-bipyridine (L2 ), are synthesized and characterized by IR, NMR, and elemental analysis. Structure of 1 was determined by single-crystal X-ray crystallography, revealing that rhenium is six-coordinate octahedral. The electrochemical, photophysical, and thermal properties of the two rhenium(I) complexes were investigated. Electroluminescent devices were fabricated by doping 1 in polymer blend host of poly(vinylcarbazole) and 2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazole using simple solution spin-coating technique. The device exhibits a maximum current efficiency of 2.97?cd?A?1 and peak brightness in excess of 2390?cd?m?2. 相似文献
995.
《Journal of Coordination Chemistry》2012,65(13):2360-2369
Four new solid ternary complexes of lanthanide with 2,6-pyridine dicarboxylic acid and α-picolinic acid [Ln(DPA)(Lα)(H2O)] · 2H2O (Ln = La3+, Ce3+, Eu3+, or Gd3+; DPA = 2,6-pyridine dicarboxylic acid; HLα = α-picolinic acid) have been synthesized and characterized by elemental analysis, molar conductance, FT-IR, UV–Vis, and TG–DTA. The antibacterial activities indicate that all the complexes exhibit antibacterial ability against Escherichia coli and Staphylococcus aureus with broad antimicrobial spectra. The anticancer activity of the La complex against K562 tumor cell in vitro is measured using methyl thiazolyl tetrazolium (MTT) colorimetry and flow cytometry. The La complex can induce K562 tumor cell apoptosis, presenting the best apoptosis effect by acting on the S period after inducing K562 tumor cell for 72 h. 相似文献
996.
CUI Zhi-Hua WANG Si-Si WANG Xiu-Guang GAO Dong-Zhao SUN Ya-Qiu ZHANG Guo-Ying XU Yan-Yan 《结构化学》2012,31(6):769-776
Two one-dimensional cobalt(Ⅱ) compounds {[Co(Hbpma)(H2O)4 ] 2 ·3SO 4 ·4.5H2O} n1 and {[Co(Hbpma)(NCS) 3 (H2O)]·2.85H2O}n2 (bpma = N,N -bis(3-pyridylmethyl)amine) have been synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in triclinic, space group P1 with a = 15.8780(5), b = 16.2187(5), c = 16.4858(5) , α = 91.0420(10), β = 94.5190(10), γ = 101.4360(10)°, V = 4145.7(2) 3 , C 24 H 53 Co 2 N 6 O 24.50 S 3 , M r = 1031.76, Z = 4, D c = 1.653 g/cm 3 , μ(MoKα) = 1.046 mm -1 , F(000) = 2148, S = 1.017, the final R = 0.0269 and wR = 0.0644 for 13032 observed reflections (I > 2σ(I)). For complex 2, it belongs to triclinic, space group P1 with a = 9.3761(11), b = 10.5814(13), c = 11.2972(14) , α = 85.472(2), β = 88.058(2), γ = 76.203(2)°, V = 1085.0(2) 3 , C 15 H 21.70 CoN 6 O 3.85 S 3 , M r = 502.79, Z = 2, D c = 1.539 g/cm 3 , μ(MoKα) = 1.112 mm -1 , F(000) = 519, S = 1.070, the final R = 0.0358 and wR = 0.0899 for 3466 observed reflections (I > 2σ(I)). Two complexes 1 and 2 are both found to be one-dimensional coordination polymers bridged by the protonated bpma ligands, which are assembled into three-dimensional supramolecular structures through the hydrogen bonding interactions and π-π packing interactions. 相似文献
997.
998.
《应用有机金属化学》2017,31(11)
In the presence of iron pentacarbonyl, photochemical reaction between phenylisocyanate and ferrocenylacetylene results in ferrapyrrolinone complex [Fe2(CO)6(μ2‐η3‐FcC═C(H)C(O)NPh)] ( 1 ) and maleimide 3‐ferrocenyl‐1‐phenyl‐1H ‐pyrrole‐2,5‐dione ( 2 ). Under similar experimental conditions, ferrocenyl−/phenyl‐substituted butadiyne primarily shows the activation of only one C☰C bond and results in ferrapyrrolinone complexes [Fe2(CO)6(μ2‐η3‐FcC═C(C☰CR)C(O)NPh)] ( 3 , R = Fc; 3a , R = Ph), maleimides 3‐ferrocenyl‐1‐phenyl‐4‐(ferrocenylethynyl)‐1H –pyrrole‐2,5‐dione ( 5 ) and 3‐ferrocenyl‐1‐phenyl‐4‐(phenylethynyl)‐1H –pyrrole‐2,5‐dione ( 5a ) and [Fe2(CO)6(μ2‐η3‐FcC═C(R)C(O)NPh)] ( 4 ; R = 3‐ferrocenyl‐1‐phenyl‐1H ‐pyrrole‐2,5‐dione). Compound 4 consists of ferrapyrrolinone and a maleimide unit, formed by the activation of both C☰C bonds of diferrocenylbutadiyne. Activation of both C☰C bonds in a substituted butadiyne is a rare observation. Formation of the ferrapyrrolinone compounds is an advance over the earlier reported methods which generally use internal alkynes and involve prior synthesis of other clusters. 相似文献
999.
《应用有机金属化学》2017,31(11)
A series of new sterically modulated chlorocoumarin‐substituted (benz)imidazolium salts and their bis‐N‐heterocyclic carbene silver(I) complexes were prepared and characterized. The complexes were prepared in good yields following the in situ deprotonation method by treating azolium salts with silver(I) oxide in the dark. All the compounds were characterized using various spectroscopic and analytical methods. Additionally, one of the benzimidazolium salts was characterized using single‐crystal X‐ray diffraction technique. In this salt, intermolecular π–π stacking interactions operate between benzimidazole as well as coumarin heterocyclic systems with adjacent molecules. In the preliminary antibacterial studies, the silver complexes were found more active than the corresponding salts against a panel of bacterial strains. Interestingly, the complexes displayed improved antibacterial efficacy against Escherichia coli strain, comparable with that of the standard drug ampicillin. 相似文献
1000.
《应用有机金属化学》2017,31(6)
A series of half‐sandwich iridium complexes ( 1 – 4 ) with thiosemicarbazone ligands in two types of coordination modes were synthesized and characterized. The molecular structures of compounds 1 , 2 and 3 were determined using single‐crystal X‐ray diffraction analysis. The nature of the complexes was studied using density functional theory calculations. The stability of the complexes was investigated using UV–visible absorption spectroscopy. The compounds were further evaluated for their in vitro antiproliferative activities against HeLa, HepG2, CNE‐2, SGC‐7901, KB and HEK‐293 T cell lines. Compound 2 displays the highest antiproliferative activity among the other analogues and cisplatin. 相似文献