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21.
Solubilities of ribidium tetraphenylborate in water,methanol,ethanol,1-propanol,1-butanol,l-pentanol,1-hexanol and 1-octanol at 288.15,298.15,308.15,318.15,328.15 K have been determined by spectrophotometry.The standard Gibbs energy of transfer of ribidium tetraphenylborate from water to straight-chain n-alkanols and the primary medium effect of rubidium tetraphenylborate from 288.15 to 328.15 K have been calculated.Furthermore,the contribution of microscopic interactions to the standard Gibbs energy of transfer of rubidium tetraphenylborate is calculated and discussed. 相似文献
22.
Yousry M. Issa Mahmoud S. Rizk Adel F. Shoukry Ehab M. Atia 《Mikrochimica acta》1998,129(3-4):195-200
The construction and general performance characteristics of two PVC membrane sensors responsive to the amprolium (AmpH2+) cation are described. These sensors are based on the ion-associates amprolium-tetraphenylborate (AmpH-TPB) and amprolium-reineckate (AmpH-Rk). The electrodes exhibit near-Nernstian response for the doubly charged amprolium cation over the concentration ranges 0.1–100 and 0.01–100 mM for AmpH-TPB and AmpH-Rk, respectively. The pH does not affect electrode performance within the range 7.0–11.0. No interferences are caused by many inorganic cations, sugars and amino acids. The isothermal coefficients are found to be 0.0001306 and 0.0010438 V/ °C for AmpH-TPB and AmpH-Rk, respectively. Potentiometric titration and standard addition methods were used to determine amprolium in pure solutions and in veterinary soluble powder, with high accuracy and precision. 相似文献
23.
In this paper, the adsorption characteristics of sodium tetraphenylborate(NaBPh4) on activated carbon at 298.2,303.2,308.2,313..2 and 323.2 K was studied.The results show that the adsorption isotherm of NaBPh4 on activated carbon at different temperatures could be described using Langrnuir equation. Furthermore, the standard Gibbs energy, enthalpy, entropy and hydrophobic interaction Gibbs energy for the adsorption of NaBPh4 on activated carbon were studied, and the result shows that the hydrophobic interaction of BPh4^- ion plays the most important role for the transfer of NaBPh4 from water to activated carbon surface. 相似文献
24.
Palladium–quaternary phosphonium phase transfer catalyst brush assembly as reusable and environmentally benign catalyst for coupling of aryl halides and sodium tetraphenylborate in neat water 下载免费PDF全文
A first example of simultaneous covalent anchoring of a palladate anion–phosphonium cation matrix on the surface of silica nanoparticles and application in the Suzuki coupling reaction of a variety of different haloarenes and sodium tetraphenylborate in neat aqueous media without the addition of any organic co‐solvent are described. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
25.
Solubilities of bis(biphenyl)chromium(I) tetraphenylborate were measured in 25, solubilities of tetraphenylarsonium tetraphenylborate in nine and solubilities of bis(biphenyl)chromium(0) in seven nonaqueous solvents. Linear dependences of the pKs-values for these compounds as well as the pKs values for tetraphenylstibonium tetraphenylborate, tetraphenylmethane and tetraphenylgermane were observed. The relations between the pKs-values of the above mentioned compounds and solvent parameters as well as solvent structure are discussed. 相似文献
26.
27.
A series of sulfonium tetraphenylborates can be readily prepared by the metathesis of sulfonium halides with sodium tetraphenylborates. After heating at 120–150 °C, the sulfonium tetraphenylborates can smoothly undergo the cross-couplings between the tetraphenylborate anions and the sulfonium cations in the absence of a metal catalyst. For carbonylmethyl-, benzyl-, and allylsulfoniums, the corresponding carbonylmethyl–phenyl, benzyl–phenyl, and allyl–phenyl cross-coupling products can be obtained in 22–76% yields. An interionic electron-transfer mechanism for this cross-coupling reaction is proposed. 相似文献
28.
T. M. Polyanskaya E. A. Ilinchik V. V. Volkov M. K. Drozdova O. P. Yureva G. V. Romanenko 《Journal of Structural Chemistry》2008,49(3):494-503
A novel compound of {[(C6H5)NH]2C=NH(C6H5)}[B(C6H5)4]·C2H5OH is prepared and examined by single crystal X-ray diffraction. Crystal data: C45H44BN3O, M = 653.64, monoclinic, space group P21/c, unit cell parameters: a = 24.375(2) Å, b = 17.5829(15) Å, c = 18.090(1) Å, β = 105.277(2)°, V = 7479.0(11) Å3, Z = 8, d
calc = 1.161 g/cm3, T = 293 K, R
1 = 0.064. The structure contains two crystallographically independent cations, two anions, and two solvate ethanol molecules.
Three types of interactions occur between them: interionic N-H(N)⋯π and N(H)⋯π⋯H(C), π-delocalized system of Ph rings of the
anions, and interaction of ions with ethanol molecules N-H⋯O-H(O)⋯π. The compound is characterized by IR and luminescence
spectra. At room temperature, the emission intensity grows with time of exposure to UV irradiation.
Original Russian Text Copyright ? 2008 by T. M. Polyanskaya, E. A. Il’inchik, V. V. Volkov, M. K. Drozdova, O. P. Yur’eva,
and G. V. Romanenko
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 3, pp. 512–521, May–June, 2008. 相似文献
29.
《Analytical letters》2012,45(9):1653-1664
Abstract The calibration response of a diquat bis(tetra-4-chlorophenylborate) (DQT. 2T4C1PB) based ISE for DQT was stable for 55 days. The ISE calibration slope and minimum detectable activity a(min) of DQT were in the ranges (S.D. in parentheses) 30(0.6) to 28(1.7) mV/log a (DQT) and 4(3) × 10?9M to 3(0.2) × 10?6M, respectively. The times for 100% response were 3 s at 1 mM and 25 s at 1 μM and the ISE was useable at pH 2 to 12 and over a sample temperature range of 2 to 50[ddot]C. Samples (2.54–244 μM DQT) could be determined using the standard addition method with about a ?5% error and a precision of 7 to 8%. For comparison, DQT was also determined by titration with sodium tetraphenylborate (NaTPB) using DQT. 2TPB and TBA. TPB ISEs as TPB sensors. The errors were in the range of 12 to 20% for DQT analysis in deionized water, sodium chloride solution or simulated serum. 相似文献
30.
Solubilities of tetraphenylarsonium tetraphenylborate(Ph4AsB-Ph4) in water,methanol,ethanol, 1-propanol,1-butanol,1-pentanol,1-hexanol and 1-octanol at T=293.2,298.2,303.2 and 308.2 K have been determined by spectrophotometry,The standard transfer Gibbs energy (△trG^0w→s) and entropy (△trS^0w→s) of Ph4AsBPh4 from water to the n-alkanols at temerature from 293.2 K to 308.2 K have been obtained.Fur-thermore,the contribution of microscopic interaction to the standard Gibbs energy of transfer for Ph4AsBPh4 was calculated and discussed,The results show that the effect of hydrophobic inderaction of Ph4AsBPh4 on its transfer process is the most im-portant factor .According to the thermodynamical principle,the transfer process of Ph4AsBPh4 from water to the n-alkanols is the entropy dominanted. 相似文献