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101.
Methyl ester from safflower seed oil of Turkish origin as a biofuel for diesel engines 总被引:1,自引:0,他引:1
The primary problems associated with the use of pure vegetable oils as fuels in compression ignition (Diesel) engines are
caused by high fuel viscosity. Transesterification of the oil with short-chain alcohols (such as methanol or ethanol) to corresponding
fatty esters is the most promising solution to the high-viscosity problem. In this work, the transesterification method was
applied to crude safflower seed oil of Turkish origin using methanol. The variables affecting the monoester yield, such as:
were investigated. In the presence of 1.0 wt% KOH as the reaction catalyst, 97.7% ester yield was achieved within 18 min at
a reaction temperature of 69 ± 1‡C using 1:7 vegetable oil-alcohol molar ratio. A significant improvement was observed in
viscosity and other physical properties with the ester product compared to the parent vegetable oil. ASTM fuel properties
of the methyl ester product were in accordance with those obtained for commercial Grade No.2-D diesel fuel. 相似文献
1. | Molar ratio of alcohol to vegetable oil; |
2. | Reaction temperature; and |
3. | Type and amount of alkali catalyst used |
102.
Avni R. Miralaï S. F. Prevot F. Morvan D. Amoroux J. Nickel H. 《Plasma Chemistry and Plasma Processing》1997,17(4):467-478
The diagnostics of the radio-frequency (induction mode) plasma expanded through a nozzle (PETN) at low pressures (100–1000 Pa) was performed by on-line optical emission spectroscopy (OES) and on line quadrupole mass spectrometry (QMS). The OES was used for evaluating the electronic, vibrational, and rotational temperatures (Te, Tv, and Tr) along the plasma reactor before and after the nozzle. The PETN gas mixtures analyzed were Ar+N2, Ar+CO, and Ar+O2with an addition of 1 vol.% N2to the last two gas mixtures. For the same conditions in the PETN the values of Te, Tv, and Tr were found to be different for the different gas mixtures and related to the depopulation of excited N
2
+
by oxygen atoms. Moreover the Ar+O2PETN aqueous solutions of lanthanum and manganese nitrates were nebulized for the deposition of LaMnO3perovskite. The QMS, in real time, measuring the mass species formed before and after the nozzle, explained the reasons in the different values of Te, Tv, and Tr for the three gas mixtures as well as for the formation of oxides in the PETN from the aqueous nitrate solutions. 相似文献
103.
The complexes of chromium(III), scandium(III) and yttrium(III) formed by 1-hydroxy-2-naphthoic acid (1,2-HNA: H2L) and 3-hydroxy-2-naphthoic acid (3,2-HNA: H2L) were investigated by potentiometry and spectroscopy at 25+/-0.1 degrees C and at an ionic strength of 0.1 M KNO3 in 50% ethanol-water (v/v) medium. The stoichiometries of these three M(III) complexes formed with these hydroxy-naphthoic acids and with hydroxo ion were defined and their formation constants were determined and compared. Thus, the removing capacities of these ligands could be examined by calculating the equilibrium concentration of Cr(III) that exists in the discharge water of various industries since Cr(III) ions are the main pollutants present during waste water treatment in our city, Bursa. 相似文献
104.
The possible application of native lipase ofNigella sativa seed in the esterification of fatty acids to glycerol was investigated, and the effect of process parameters and the enzyme
selectivity on the reaction were determined. For this aim, the esterification of oleic acid, sunflower oil fatty acids, and
coco oil fatty acids with glycerol were studied. 相似文献
105.
Acikbas Yaser Aksoy Mehmet Aksoy Merve Karaagac Damla Bastug Elif Kursunlu Ahmed Nuri Erdogan Matem Capan Rifat Ozmen Mustafa Ersoz Mustafa 《Journal of inclusion phenomena and macrocyclic chemistry》2021,100(1-2):39-54
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Pillar[n]arene is one of the most favorited supramolecular materials that possess a special chiral structure. The major property of... 相似文献
106.
O. Baykara M. İnceöz F. Külahcı M. Doğru E. Aksoy 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(1):59-63
222Rn concentrations along the seismic active area (some distinct in East Anatolian Active Fault System (EAFS), Turkey) were
determined by using passive and active (prompt) methods including CR-39 and Markus-10, respectively. It was observed that
the changing of 222Rn concentration along the fault lines, crossing the main East Anatolian Fault Line, has shown similar characteristics for
both methods. The mean 222Rn concentrations were found to be between 1.2 and 3.6 kBq·m−3 and, 2 and 70 kBq·m−3 by using passive and prompt methods, respectively. Nevertheless, some measured terrestrial gamma-radiation dose rate in the
same area has weak positive correlation to 222Rn concentration. Terrestrial gamma-dose rate at 1 m above the ground in the same sampling point, as for 222Rn concentration measurement were made, varied from 8.5 to 10.6 μR·h−1. 相似文献
107.
The crystal structure of N‐[(1Z)‐1‐(3‐methyl‐3‐phenylcyclobutyl)‐2‐thiomorpholin‐4‐ylethylidene] thiourea (C18H26N4S2) has been determined by X‐ray crystallographic techniques. The compound crystallizes in the orthorhombic space group Pbca, with unit cell parameters: a = 15.692(3), b = 20.803(8), c = 11.979(6)Å, Z = 8, V = 3911(7)Å3. The crystal structure was solved by direct methods and refined by full‐matrix least squares to a final R‐value of 0.084 for 1447 observed reflections [I > 2σ ( I ) ]. In the thiosemicarbazide moiety, the S = C bond length is 1.656(6), N‐C‐N angle is 115.6(5)°. The crystal structure is stabilized by the intermolecular N‐H...S hydrogen bonds. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
108.
Thrombus formation and blood coagulation is a major problem associated with blood contacting products such as catheters, vascular grafts, arteries, artificial hearts and heart valves. An intense research is being conducted towards the synthesis of new hemocompatible materials and modifications of surfaces with biological molecules. In this study, polyurethane (PU) films were synthesized in medical purity from diisocyanate and polyol without using any other ingredients and their surfaces were modified by covalent immobilization of heparin. Two types of heparin, unfractionated (UFH) and low molecular weight heparin (LMWH), were immobilized to investigate their effect on cell adhesion. The surface properties of the modified PUs were examined with ESCA, ATR-FTIR and AFM. ESCA results demonstrated sulfur peaks indicating the presence of heparin and AFM results showed the alteration of surface structure after coating with heparin. Cell adhesion studies were conducted with heparinized whole human blood. The surfaces of the UFH immobilized films resulted in lesser red blood cell adhesion in comparison to LMWH demonstrating strong anti-thrombogenic activity of the latter. 相似文献
109.
A. Aksoy 《中国物理C(英文版)》2015,39(6):067002-067002
The TAC(Turkish Accelerator Center) project aims to build an accelerator center in Turkey. The first stage of the project is to construct an Infra-Red Free Electron Laser(IR-FEL) facility. The second stage is to build a synchrotron radiation facility named TURKAY, which is a third generation synchrotron radiation light source that aims to achieve a high brilliance photon beam from a low emittance electron beam at 3 Ge V. The electron beam parameters are highly dependent on the magnetic lattice of the storage ring. In this paper a low emittance storage ring for TURKAY is proposed and the beam dynamic properties of the magnetic lattice are investigated. 相似文献
110.
Naim Hasani Teuta Selimi Altin Mele Veprim Thai Jeton Halili Avni Berisha Makfire Sadiku 《Molecules (Basel, Switzerland)》2022,27(6)
The interaction of methylene blue (MB) dye with natural coal (collected from coal landfills of the Kosovo Energy Corporation) in aqueous solutions was studied using adsorption, kinetics, and thermodynamic data, and Monte Carlo (MC) calculations. In a batch procedure, the effects of contact duration, initial MB concentration, pH, and solution temperature on the adsorption process were examined. The Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich (D–R) isotherms were used to examine the equilibrium adsorption data. The equilibrium data fit well to the Freundlich and Langmuir adsorption isotherm models; however, the Freundlich model suited the adsorption data to a slightly better extent than the Langmuir model. The kinetics experimental data was fitted using pseudo-first-order, first-order, pseudo-second-order, second-order, Elvoich equation, and diffusion models. The pseudo-second-order rate model manifested a superlative fit to the experimental data, while the adsorption of MB onto coal is regulated by both liquid film and intraparticle diffusions at the same time. Thermodynamic parameters, such as Gibbs free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were calculated. The adsorption of MB was confirmed to be spontaneous and endothermic. The theoretical results were in agreement with the experimental ones. 相似文献