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91.
Mohammad Reza Ganjali Hamid Khoshsafar Farnoush Faridbod Ali Shirzadmehr Mehran Javanbakht Parviz Norouzi 《Electroanalysis》2009,21(19):2175-2178
Room temperature ionic liquids (RTILs), 1‐n‐butyl‐3‐methylimidazolium tetrafluoroborate, [bmim]BF4, and multiwalled carbon nanotubes (MWCNTs) were used for improvement of a praseodymium carbon paste ion selective sensor response. [bmim]BF4 can be a better binder than mineral oils. MWCNTs have a good conductivity which helps the transduction of the signal in carbon paste electrode. The characteristics of these electrodes as potentiometric sensors were evaluated and compared with PVC membrane sensor. The results indicate that potentiometric sensor constructed with ionic liquid shows an increase in performance in terms of Nernstian slope, selectivity, response time, and response stability compared to Pr(III) PVC membrane sensor. 相似文献
92.
Silvia Zamponi Anna M. Kijak André J. Sommer Roberto Marassi Pawel J. Kulesza James A. Cox 《Journal of Solid State Electrochemistry》2002,6(8):528-533
The inclusion of a generation-4 polyamidoamine (G4-PAMAM) dendrimer in a silica sol-gel yielded a solid electrolyte that
was used to encapsulate Prussian Blue (PB), iron(III) hexacyanoferrate(II), and cobalt hexacyanoferrate. The PB was synthesized
in the doped silica by sequential immersion of a monolith in 0.1 M K4Fe(CN)6, water, and 0.1 M FeCl3. Inclusion of G4-PAMAM resulted in a nanoporous anion-exchange material with a capacity of 10.1 mmol g–1, which is about four times greater than the capacity of silica alone. Relative to its G0 counterpart, the G4-PAMAM doped
silica increased the rate of formation of PB by a factor of ca. 20. The solid state voltammetry of PB in the doped silica
had the usual features for this compound. At 0.1 V vs. a Ag quasi-reference electrode, a reversible reduction was seen; the
relationship between current and scan rate was that for a surface-confined redox couple. The quasi-reversible oxidation of
PB was observed at 0.85 V. Inclusion of G4-PAMAM increased the lifetime of silica as a solid electrolyte from a few days to
at least three months. Raman microprobe mapping analysis demonstrated that PB was homogeneously distributed across the entire
width (ca. 1 mm) of the G4-doped monolith with 20-h immersions.
Electronic Publication 相似文献
93.
94.
《Electroanalysis》2005,17(4):319-326
Thallium hexacyanoferrate films have been prepared from various aqueous electrolyte solutions using consecutive cyclic voltammetry. The cyclic voltammograms recorded the direct deposition of thallium hexacyanoferrate films from the mixing of Tl3+ and [Fe(CN)6]3? ions from solutions of seven cations: Li+, Na+, K+, Rb+, Cs+, H+, and Tl+. An electrochemical quartz crystal microbalance (EQCM) and cyclic voltammetry were used to study the in situ growth of the thallium hexacyanoferrate films. The thallium hexacyanoferrate film shows a single redox couple with a formal potential between +0.6 V and +1.2 V, and shows a cation effect (H+, Li+, Na+, K+, Rb+, Cs+, and Tl+). A mixed film and a two‐layered modified electrodes composed of a thallium hexacyanoferrate film with cobalt(II) hexacyanoferrate film were prepared. 相似文献
95.
A Praseodymium Salt of Dichloroacetic Acid: [Pr(HCl2C—COO)3(H2O)3]2(HCl2C—COOH)(H2O)2 The new dichloroacetate of praseodymium, [Pr(HCl2C—COO)3(H2O)3]2(HCl2C—COOH)(H2O)2, crystallizes from the solution of ?Pr6O11”? in dichloroacetic acid. The crystal structure (monoclinic, P21/n, Z = 4, a = 1598.4(2), b = 1600.8(2), c = 1650.8(2) pm, β = 105.57(1)°) contains dimeric building units of the composition [Pr2(HCl2C—COO)6(H2O)6] which are connected to chains. An additional dichloroacetic acid molecule and two crystal water molecules are included between these chains. 相似文献
96.
Cs2(H3O)Pr(CH3COO)6 and Cs2Pr(CH3COO)5: Synthesis, Crystal Structures and Thermolysis. Analogous Acetates with Lanthanum through Terbium Single crystals of Cs2(H3O)Pr(CH3COO)6 are obtained as green plates from an acetic acid solution (≈50%) of Cs2CO3 and Pr(CH3COO)3 · 1,5 H2O. The crystal structure monoclinic, Cm, Z = 2, a = 1 540.4(4), b = 691.3(2), c = 1 221.5(4) pm, β = 104.60(5)°, Vm = 379.1(2) cm3/mol, R = 0.040, Rw = 0.035 was determined from four-circle-diffractometer data. The structure consists of monomeric Pr(CH3COO)3 units, in which Pr3+ is surrounded by nine oxygen atoms. These monomers are linked together to infinite layers parallel (001) by common acetate oxygen atoms with two ?molecules”? of Cs(CH3COO). Together with an additional acetate ion coordinated to one of the Cs+ ions the composition of the layers is [Cs2Pr(CH3COO)6]?. Between these layers H3O+ is located for electroneutrality. Thermal decomposition of Cs2(H3O)Pr(CH3COO)6 was examined with thermoanalytical methods (TG/DTA with coupled gas analysis), Guinier-Simon technique and IR spectroscopy: beginning at 70°C the compound looses water and acetic acid. It decomposes topotactically to Cs2Pr(CH3COO)5. At 270°C this acetate decomposes to Cs2CO3 and Pr2O2CO3 which emits CO2 at 600°C form ing Pr2O3or PrO2?x Single crystals of Cs2Pr(CH3COO)5 were obtained from Pr(CH3COO)3, in molten Cs(CH3COO) at about 200°C. The crystal structure tetragonal, P43, Z = 4, a = 1 174,5(2), c = 1 480,5(3) pm, Vm = pin,307,5(1) cm3/mol, R = 0,061, Rw= 0,031 again consists of Pr(CH3COO)3, monomers where Pr3+ has 9 oxygen ligands in its first coordination sphere. They are linked together by two ”molecules“ of cesium acetate to infinite chains along [00l] around the 4, screw axis. There are also acetate bridges between these chains. Isotypic compounds Cs2(H3O)M(CH3COO)6 and Cs2M(CH3COO)5, and Cs2M(CH3COO)5with M = La? Tb, were obtained from acetic acid solutions or thermal decomposition and were characterized by X-ray Guinier techniques. 相似文献
97.
Koksharova T. V. Ptashchenko A. A. Masleeva N. V. Fel'dman S. V. Pasternak N. N. Stukalov S. A. 《Theoretical and Experimental Chemistry》2002,38(4):263-267
The temperature dependence of the resistivity of tablets of hexacyanoferrate(II)–thiosemicarbazide complexes of chromium(III), manganese(II), iron(III), cobalt(III), nickel(II), copper(II), and zinc(II) was measured in the range 20-90 °C. A relationship between the conductivity of a substance and the rate constant for the catalytic decomposition of hydrogen peroxide is established. 相似文献
98.
The oxidation of Na4Fe(CN)6 complex by S2O anion was found to follow an outer‐sphere electron transfer mechanism. We firstly carried out the reaction at pH=1. The specific rate constants of the reaction, kox, are (8.1±0.07)×10?2 and (4.3±0.1)×10?2 mol?1·L·s?1 at μ=1.0 mol·L?1 NaClO4, T=298 K for pH=1 (0.1 mol·L?1 HCl04) and 8, respectively. The activation parameters, obtained by measuring the rate constants of oxidation 283–303 K, were ΔH≠=(69.0±5.6) kJ·mol?1, ΔS≠=(?0.34±0.041)×102 J·mol?1·K?1 at pH=l and ΔH≠=(41.3±5.5) kJ·mol?1, ΔS≠=(?1.27±0.33)×102 J·mol?1·K?1 at pH=8, respectively. The cyclic voltammetry of Fe(CN) shows that the oxidation is a one‐electron reversible redox process with E1/2 values of 0.55 and 0.46 V vs. normal hydrogen electrode at μ=1.0 mol·L?1 LiClO4, for pH=1 and pH=8 (Tris). respectively. The kinetic results were discussed on the basis of Marcus theory. 相似文献
99.
K. Rossmanith 《Monatshefte für Chemie / Chemical Monthly》1994,125(10):1027-1031
Summary Lanthanum ammonium nitrate of purity 97%, containing 34.1 kgRE
2O3, was crystallized fractionally and yielded 32.5 kg oxide of purity better than 99.9% (the larger part was 99.99% pure). Out of mixtures with 66% Pr there resulted praseodymium ammonium nitrate containing 13.45 kg oxide of purity better than 99.5%. The effective separation factors are discussed, showing a better efficiency of the ammonium than of the magnesium double nitrates for the separation of praseodymium and lanthanum. 相似文献
100.
研究了沉积在玻碳(GC)基体上的铁氰化镍(NiHCF)膜的电化学行为,详细分析了制备条件对膜的循环伏安(CV)行为的影响,结合能量色散X射线(EDX)分析技术,提出膜是可溶组分K2NiFe(CN)6和不可溶组分Ni2Fe(CN)6共存的混合态,精确控制沉积条件,可分别获得不同组分占优势的膜.在此基础上研究了两组分的电化学特征,初步探讨了不可溶组分的电化学反应机制,得到描述其电极反应的方程式为: 相似文献