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991.
Jian Bin LUO Qiang WANG Hong TAN Jie Hua LI Yin Ping ZHONG College of Polymer Science Engineering Sichuan University Chengdu College of Chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu Key Laboratory of Bio-resources Eco-environment 《中国化学快报》2006,(11)
In order to resolve the increasing resistance phenomena of the Gram-negative bacteria against single chain quaternary ammonium salts (QAS), lysine with a pedant fluorinated bis-ammonium salts was synthesized and its antimicrobial properties were evaluated in this work. The novel fluorinated bis-ammonium salts shows similar activity with conventional single chain quaternary ammonium salts against Gram-positive bacteria but stronger activity against Gram-negative bacteria and yeast compared with the single chained counterpart. 相似文献
992.
The capacity of solubilization of the five physiological bile salts: cholate, deoxicholate, hiocholate, quenodeoxicholate and taurocholate were assayed on two low aqueous soluble antimicotic agents: griseofulvin and ketoconazole. The fluorescence emission of these antimicotic agents was used as tool to study their solubilization in bile salts micelle. Griseofulvin enhanced its fluorescence and shifted to the blue in the presence of bile salts micelles. The shift was dependent of the polarizability of the micelle zone where the antimicotic is located. Cholate and deoxicholate showed a good solubilization capacity for griseofulvin: 321 mol and 394 mol surfactant per mol of antimicotic, respectively. These values decreased in the presence of NaCl in agreement with a compactness of the micelle due to an electrostatic repulsion decreasing between the bile salts monomer negatively charged. The imidazole and piperazine rings present in the ketoconazole molecule give to this the capacity of fluorescence emission with two vibronic bands at 364 nm and 382 nm, respectively. The solubilization in cholate micelle induced an increase in the band at 382 nm, while deoxicholate induced the opposite effect, suggesting a strong intercation between the polar groups of ketoconazole molecule (imidazole and piperazine rings) and the OH of these bile salts. The solubilization capacities were 47 mol and 117 mol surfactant per ketoconazole mol for cholate and deoxicholate, respectively. The other bile salts assayed did not show any appreciable solubilization capacity. Ketoconazole and griseofulvin solubilized in micelles of cholate and deoxicholate were stable during the thermal recycling treatment for over 100 days. 相似文献
993.
K. Mohan Reddy N. Lingaiah P. S. Sai Prasad I. Suryanarayana 《Journal of solution chemistry》2006,35(3):407-423
Using a potentiometric mass titrationmethod, the pKa values of 12-molybdophosphoric acid (MPA) and 12-tungstophosphoric acid (TPA) were determined in aqueous solution and as
a solid suspension in acetonitrile. The results were compared with the earlier reported values obtained using other methods
like calorimetry and adsorption (Cal-ad). The acidity values in terms of pKa and the number of acid sites were determined for the ammonium salts of MPA and TPA, and ammonium salts incorporated with
vanadium and ammonium salts impregnated on a ZrO2 support. The effect of the amount of the salt or acid in the suspension of acetonitrile on the potentiometric titration behavior
was also studied and it was found that 0.1 g of the substance gives a good neutralization jump in the titration curve. 相似文献
994.
G. T. Sukhanov A. G. Sukhanova Yu. V. Ilyasova 《Chemistry of Heterocyclic Compounds》2006,42(9):1197-1199
The reaction of 3-nitro-5-R-1,2,4-triazoles with diethyl sulfate gives 1-ethyl-3-R-5-nitro-, 4-ethyl-3-nitro-5-R-1,2,4-triazoles,
1,4-diethyl-, 1,4-diethyl-3-methyl-1,2,4-triazol-5-ones, and 1,4-diethyl-3-nitro-5-R-1,2,4-triazolium salts. When compared
with the use of dimethyl sulfate as alkylating agent the ethylation products have a markedly increased fraction of triazolones
(up to 30–37%) and a somewhat lowered yield of nitrotriazolium salts (up to 6–10%). The reaction time is increased by an order.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1378–1381, September, 2006. 相似文献
995.
S. V. Korenev E. V. Makotchenko P. E. Plyusnin I. A. Baidina Yu. V. Shubin 《Russian Chemical Bulletin》2006,55(3):429-434
Double complex salts [Au(C4H13N3)Cl][MCl6]·nH2O (M = Ir, Pt; n = 0–2) were synthesized. According to X-ray diffraction data, compounds with n = 1.5 are isostructural; the crystal structure is composed of the complex cations [Au(dien)Cl]2+ (dien is diethylenetriamine), the complex anions [MCl6]2−, and water molecules of crystallization. Thermolysis of the double complex salts under hydrogen and helium was studied. The
formation of nonequilibrium solid solutions based on Ir in the Au-Ir system and based on Pt in the Au-Pt system was demonstrated.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 416–421, March, 2006. 相似文献
996.
The chemical oxidation of aniline with ammonium peroxydisulfate to form polyaniline (PANI) films has been studied in different aqueous acid mediums such as HCl, HNO3, and H2SO4. The yield and the growth rate of the PANI film deposition were measured using the quartz crystal microbalance (QCM) technique. The effect of different salts such as KCl, NaNO3, and K2SO4 and their concentration on the yield and the growth rate of the film formation are investigated. The yield of PANI film deposition depends on the acid used and the type of salts as well as their concentrations. When HCl and HNO3 were used as media, the addition of salts with the same anion has no effect. However, when H2SO4 was used as media, the addition of salts with the same anions as the medium enhances the yield of PANI film deposition. The UV–visible spectra of the produced PANI films in the absence and presence of the salts are also studied. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
997.
The reaction of alkynyldifluoroboranes RC≡CBF2 (R = (CH3)3C, CF3, (CF3)2CF) with organyliodine difluoride R′IF2 bearing electron‐withdrawing polyfluoroorganyl groups R′ = C6F5, (CF3)2CFCF=CF, C4F9, and CF3CH2 leads to the corresponding alkynyl(organyl)iodonium salts [(RC≡C)(R′)I][BF4]. This approach uses a widely applicable method as demonstrated for a representative series of polyfluorinated aryl‐, alkenyl‐, and alkyliodine difluorides. Generally, these syntheses proceed with good yields and deliver pure iodonium salts. The distinct electrophilic nature of their [(RC≡C)(R′)I]+ cations is deduced from multinuclear magnetic resonance data. Within the series of new iodonium salts [CF3C≡C(C4F9)I][BF4] is an intrinsic unstable one and decomposed forming CF3C≡CI and C4F10. 相似文献
998.
Huang H Zhou Z Song J Liang L Wang K Cao D Sun W Dong X Xue M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(48):13593-13602
Energetic salts based on dipicrylamine and its amino derivative were synthesized. All salts were fully characterized by multinuclear NMR spectroscopy ((1)H, (13)C), vibrational spectroscopy (IR), and elemental analysis. Ethylenediammonium di-DPA (DPA=dipicrylamine) and 1,3-diaminoguanidinium DPA were further confirmed by single-crystal X-ray diffraction. These salts exhibit reasonable physical properties, such as high densities (1.71-1.81 g cm(-3)), good thermal stabilities (T(d) =155-285 °C), and low solubilities in water. The impact sensitivity of 1-methyl-3,4,5-triamino-1,2,4-triazolium DPA is lower than that of 2,4,6-trinitrotoluene (TNT), and for some other energetic salts their impact sensitivities are comparable to that of TNT. Based on experimental densities and theoretical calculations carried out by using the Gaussian 03 suite of programs, all the salts have calculated detonation pressures (22.5-27.8 GPa) and velocities (7226-7917 m s(-1)) that exceed those of conventional TNT. The toxicities of these salts measured by luminescent bacteria toxicity tests are much lower than that of TNT, and two binary eutectic mixtures with melting points that fall between 70 and 100 °C were identified. 相似文献
999.
Kristian Radan 《Journal of fluorine chemistry》2011,132(10):767-771
The compounds, Cd(BF4)(TaF6) and Cd(BF4)(BiF6), have been synthesized and characterized by single-crystal X-ray diffraction and Raman spectroscopy. Both isostructural compounds crystallize in the monoclinic P21/c space group with a = 8.2700(6) Å, b = 9.3691(6) Å, c = 8.8896(7) Å, β = 94.196(3)°, V = 686.94(9) Å3 for Cd(BF4)(TaF6) and a = 8.3412(8) Å, b = 9.4062(8) Å, c = 8.9570(7) Å, β = 93.320(5)°, V = 701.58(11) Å3 for Cd(BF4)(BiF6). Eight fluorine atoms (4 BF4− + 4 AF6−) form a surrounding around the cadmium atom in the shape of distorted square antiprism. These compounds are not isostructural with mixed-anion analogues of Ca, Sr, Ba and Pb studied earlier. 相似文献
1000.
Met.(Cu,Ag)-TCNQ有机薄膜的EB CL像 总被引:1,自引:0,他引:1
自从1979年Potember等人首先发现了CuTCNQ有机薄膜具有受电流控制的电开关特性以来[1],有关CuTCNQ及AgTCNQ这些阴离子基过渡金属盐(以下简称为Met.(CU、Ag)-TCNQ)有机薄膜的光存储特性、光电开关特性,以及某些气教特性的研究结果便不断报导出来[2-4],引起人们极大的兴趣.作为很有前途的有机光电功能材料,至今对其电导及光电特性的机理研究仍显得十分薄弱,极大影响了它们进一步向实用器件方向的发展.由于CuTCNQ的晶体参数至今未见报导,我们依据CuTCNQ粉末X射线小角衍射谱对比AgTCNQ相应的粉末X射线衍射数据,… 相似文献