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991.
The synthesis of 4-substituted indazole derivatives by palladium-mediated cross-coupling reactions was described. Suzuki, Heck, Sonogashira and Stille cross-coupling reactions were used to introduce aryl, vinyl and alkynyl substituents in 4-position of indazole derivatives. The selectivity of bis-Suzuki reactions of 3,4-diiodo- and 3-bromo-4-iodoindazoles was investigated. 相似文献
992.
Mitra Ghassemzadeh Masoomeh Tabatabaee Mostafa M. Pooramini Majid M. Heravi Abbas Eslami Bernhard Neumüller 《无机化学与普通化学杂志》2006,632(5):786-792
The reaction of 4‐amino‐6‐methyl‐1,2,4‐triazin‐thione‐5‐one (H2AMTTO, 1 ) with 4‐chlorobenzaldhyde led to the corresponding iminic compound {(4‐[(4‐chloro‐benzylidene)‐amino]‐6‐methyl‐3‐thioxo[1,2,4]‐triazin‐3,4‐dihydro(2H)‐5‐one), CAMTTO ( 2 ). Treatment of 2 with copper(I) chloride in chloroform gave the dimeric complex [{(CAMTTO)2CuCl}2]·2CHCl3 ( 3 ). Treatment of 2 with copper(I) chloride and silver(I) nitrate in the presence of the co‐ligand triphenylphophane gave the complexes [(CAMTTO)CuCl(PPh3)2] ( 4 ) and [(CAMTTO)Ag(PPh3)2]NO3·2CHCl3 ( 5 ). All compounds have been characterized by elemental analyses, 1H NMR spectroscopy, IR spectroscopy, and partly by mass spectrometry and X‐ray diffraction studies. In addition 4 and 5 have been characterized by 31P{1H} NMR spectroscopy. Crystal data for 2 at ?80 °C: monoclinic, space group P21/c, a = 1370.3(1), b = 767.8(1), c = 1268.7(1) pm, β = 107.12(1)°, Z = 4, R1 = 0.0379; for 3 at ?80 °C: monoclinic, space group P21/c, a = 1442.6(2), b = 878.8(1), c = 2558.7(3) pm, β = 95.31(1)°, Z = 2, R1 = 0.0746; for 4 at ?80 °C: triclinic, space group , a = 1287.9(1), b = 1291.7(1), c = 1359.5(1) pm, α = 90.44(1)°, β = 94.81(1)°, γ = 107.54(1)°, Z = 2, R1 = 0.0359 and for 5 at ?80 °C: triclinic, space group , a = 1060.5(1), b = 1578.2(2), c = 1689.6(2) pm, α = 87.70(1)°, β = 86.66(1)°, γ = 76.84(1)°, Z = 2, R1 = 0.0487. 相似文献
993.
A study was carried out comparing silica fume (SF) and dealuminated kaolin (DK) as pozzolanic materials in blended cements. Ten, 20 or 30 wt% of SF or DK were substituted for Portland cement. The kinetics of hydration up to 45 h were studied using isothermal conduction calorimetry. Blends containing pozzolanic materials usually have decreased heats of hydration compared to pure cement during the period of C3S hydration, i.e. during the main hydration peak. Depending on the chemical composition and the activity of the pozzolan, the reaction taking place with the lime typically contributes to the heat output after the main hydration peak.The pozzolanic activity of DK is the principal factor and heat evolution increases with respect to pure PC mortar, during the first 15 h. The presence of hydrated silica (silanol groups) in DK increases the pozzolanic activity especially before and during induction period. The acidic silanol sites are capable of a fast acid-base reaction with the alkalis and with any Ca(OH)2 present in cement during the induction period. 相似文献
994.
Ghoshal D Maji TK Mostafa G Sain S Lu TH Ribas J Zangrando E Chaudhuri NR 《Dalton transactions (Cambridge, England : 2003)》2004,(11):1687-1695
Four succinato-bridged complexes of copper(II) have been synthesized. Complex 1, [Cu(2)(mu-OH(2))(2)L(bpy)(2)(NO(3))(2)](n) and 2, [Cu(2)(mu-OH(2))(2)L(phen)(2)(NO(3))(2)](n)(bpy = 2,2[prime or minute]-bipyridine; phen = 1,10-phenanthroline and LH(2)= succinic acid) exhibit 1D coordination polymer structures where both the nitrate ions are directly linked to the copper(ii) producing synthons in a 2D sheet. A novel 2D grid-like network, ([Cu(4)L(2)(bpy)(4)(H(2)O)(2)](ClO(4))(4)(H(2)O))n3, is obtained upon changing the nitrate by perchlorate anion in complex 1, where the channels are occupied by the anions. On changing the nitrate by tetrafluoroborate anion in complex 2, a novel octanuclear complex, [Cu(8)L(4)(phen)(12)](BF(4))(8).8H(2)O 4, is isolated. The coligand bpy and phen in these complexes show face-to-face (in 1,2,3,4) or edge-to-face (in 4 )pi-pi interactions forming the multidimensional supramolecular architectures. Interestingly, the appearance of edge-to-face pi-pi interactions in complex facilitates the formation of discrete octanuclear entities. Variable-temperature (300-2 K) magnetic measurements of complexes have been done. Complexes 1 and 2 show very weak antiferromagnetic (OOC-CH(2)-CH(2)-COO) and ferromagnetic coupling (mu-H(2)O). Complex 3 also shows antiferromagnetic (syn-syn mu-OCO), and ferromagnetic coupling (mu-O of the -COO group). Complex 4 with two types (syn-syn and syn-anti) of binding modes of the carboxylate group shows strong antiferromagnetic interaction. 相似文献
995.
New triiodomercurate-modified carbon paste electrode for the potentiometric determination of mercury
A new tetrazolium-triiodomercurate-modified carbon paste electrode has been described for the sensitive and selective determination of mercury. The electrode shows a stable, near-Nernstian response for 1×10−3 to 6×10−6 M [HgI3]− at 25 °C over the pH range of 4.0-9.0, with an anionic slope of 55.5±0.4 mV. The lower detection limit is 4×10−6 M with a fast response time of 30-50 s. Selectivity coefficients of a number of interfering anions and iodo complexes of some metal ions have been estimated. The interference from many of the investigated ions is negligible. The determination of 1-200 μg/ml of mercury in aqueous solutions shows an average recovery of 98.5% and a mean relative standard deviation of 1.6% at 50.0 μg/ml. The direct determination of mercury in spiked wastewater, metal amalgams and dental alloy gave results that compare favorably with those obtained by the cold vapor atomic absorption spectrometric method. Potentiometric titration of mercury and phenylmercury acetate with standard potassium iodide has been monitored using the developed triiodomercurate-carbon paste electrode (CPE) as an end point indicator electrode. 相似文献
996.
Mostafa Mimouni Sébastien Perrier Yvon Pointud Jean Juillard 《Journal of solution chemistry》1993,22(9):769-785
Interactions of ionophore monensin with heavy metal monovalent cations, Ag+, Tl+, Hg
2
2+
, were studied in methanol and in various biphasic waterorganic solvent systems to supplement previous data on alkali-metal cations. The species formed were identified and the corresponding formation constants determined. Enthalpies of formation were also obtained in methanol for Ag+ and Tl+ from calorimetric measurements. The results for monovalent cations in general are discussed in terms of cation size and solvation, and structure of the ionophore anion. 相似文献
997.
Mona S. Alsaeedi Bandar A. Babgi Magda H. Abdellattif Abdesslem Jedidi Mark G. Humphrey Mostafa A. Hussien 《Molecules (Basel, Switzerland)》2021,26(1)
Ruthenium(II) arene complexes of the general formula [RuCl(η6-p-cymene)(diamine)]PF6 (diamine = 1,2-diaminobenzene (1), 2,3-diaminonaphthalene (2), 9,10-diaminophenanthrene (3), 2,3-diaminophenazine (4), and 1,2-diaminoanthraquinone (5) were synthesized. Chloro/aqua exchange was evaluated experimentally for complexes 1 and 2. The exchange process was investigated theoretically for all complexes, revealing relatively fast exchange with no significant influence from the polycyclic aromatic diamines. The calf thymus DNA (CT-DNA) binding of the complexes increased dramatically upon extending the aromatic component of the diamines, as evaluated by changes in absorption spectra upon titration with different concentrations of CT-DNA. An intercalation binding mode was established for the complexes using the increase in the relative viscosity of the CT-DNA following addition of complexes 1 and 2. Theoretical studies showed strong preference for replacement of water by guanine for all the complexes, and relatively strong Ru–Nguanine bonds. The plane of the aromatic systems can assume angles that support non-classical interactions with the DNA and covalent binding, leading to higher binding affinities. The ruthenium arenes illustrated in this study have promising anticancer activities, with the half maximal inhibitory concentration (IC50) values comparable to or better than cisplatin against three cell lines. 相似文献
998.
Souad Rakass Hicham Oudghiri Hassani Ahmed Mohmoud Fethi Kooli Mostafa Abboudi Eman Assirey Fahd Al Wadaani 《Molecules (Basel, Switzerland)》2021,26(5)
Removing methylene blue (MB) dye from aqueous solutions was examined by the use of nickel molybdate (α-NiMoO4) as an adsorbent produced by an uncomplicated, rapid, and cost-effective method. Different results were produced by varying different parameters such as the pH, the adsorbent dose, the temperature, the contact time, and the initial dye concentration. Adsorbent dose and pH had a major removal effect on MB. Interestingly, a lower amount of adsorbent dose caused greater MB removal. The amount of removal gained was efficient and reached a 99% level with an initial methylene blue solution concentration of ≤160 ppm at pH 11. The kinetic studies indicated that the pseudo-second-order kinetic model relates very well with that of the obtained experimental results. The thermodynamic studies showed that removing the MB dye was favorable, spontaneous, and endothermic. Impressively, the highest quantity of removal amount of MB dye was 16,863 mg/g, as shown by the Langmuir model. The thermal regeneration tests revealed that the efficiency of removing MB (11,608 mg/g) was retained following three continuous rounds of recycled adsorbents. Adsorption of MB onto α-NiMoO4 nanoparticles and its regeneration were confirmed by Fourier transform infrared spectroscopy (FTIR) analysis and scanning electron microscopy (SEM) analysis. The results indicated that α-NiMoO4 nanosorbent is an outstanding and strong candidate that can be used for removing the maximum capacity of MB dye in wastewater. 相似文献
999.
Mostafa M. Amini Amirreza Azadmeher S.W. Ng 《Journal of organometallic chemistry》2007,692(18):3922-3930
The di- and triorganotin(IV) derivatives of anthracenecarboxylic acid, Ph2MeSnOC(O)C14H9 (2), Me3SnOC(O)C14H9 (3), Me2Sn[OC(O)C14H9]2 · CH3OH (4) Ph3SnOC(O)C14H9 · CH3OH (5), Ph2EtSnOC(O)C14H9 (6), Ph2Sn[OC(O)(C14H9)]2 (7) and PhMe2SnOC(O)C14H9 (8) were synthesized by the reaction of Ph2MeSnI, Me3SnCl, Me2SnCl2, Ph3SnCl, Ph2EtSnI, Ph2SnCl2, and PhMe2SnI with 9-anthracenecarboxylic acid, respectively, with the aid of potassium iso-propoxide. All complexes were characterized by elemental analysis, mass spectrometry, IR, 1H, 13C and 119Sn NMR spectroscopes. The molecular structures of complexes 2, 3 and 4 were determined by single crystal X-ray analysis. The X-ray structures reveal that complex 2 and 3 adopt a polymeric trans-C3SnO2 trigonal bipyamidal configuration with the oxygen atoms occupying axial positions. Complex 4 adopts a monomeric structure with two carboxylates coordinated to tin in a monodentate form from axial and equatorial positions, and with the coordination number raised to five as the methanol occupies the apical position of the trigonal bipyramid. 相似文献
1000.
Brahim Bennani Bouchra Filali Baba Najib Ben Larbi Abdelatif Boukir Abdelali Kerbal Mostafa Mimouni Taibi Ben Hadda Bartosz Trzaskowski Abraham F. Jalbout 《Journal of heterocyclic chemistry》2007,44(3):711-716