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1.
Multimedia Tools and Applications - Neurodegenerative disease defined about death of some brain parts. This disease is the dangerous disease to cure with devastating results. In addition to the...  相似文献   
2.
We discuss the thermoelectric properties of Na x CoO2 using the electronic structure, as determined in first principles calculations, and Boltzmann kinetic transport theory. The Fermi energy lies near the top of a manifold of Co t 2g bands. These t 2g bands are separated by a large gap from the higher-lying e g states. Although the large crystal-field splitting implies substantial Co–O hybridization, the bands are narrow. Application of standard Boltzmann transport theory to such a narrow band structure yields high thermopowers in accord with experimental observations, even for high metallic carrier densities. The high thermopowers observed for Na x CoO2 can therefore be explained by standard band theory and do not rely on low dimensionality or correlation effects specific to Co. We also present results for the cubic spinel structure ZnRh2O4. Like Na x CoO2, this compound has very narrow valence bands. We find that if it could be doped with mobile carriers, it would also have a high thermopower, comparable with that of Na x CoO2.  相似文献   
3.
Fermentation-derived ammonium lactate was converted into ethyl lactate by decomposition in various organic solvents followed by esterification with ethanol over Amberlyst catalyst. The ammonium lactate was decomposed more efficiently in an organic solvent with high boiling point, where the produced lactic acid was stabilized well as a monomer without oligomerization. However, only the nonreactive phosphate-type solvent such as triethyl phosphate and tributyl phosphate showed a notable ethyl lactate yield in the subsequent esterification reaction compared with dimethyl sulfoxide and N-methyl pyrolidine. The lactic acid yield in ammonium lactate decomposition and the subsequent ethyl lactate yield were also highly dependent on solvent ratio to ammonium lactate, temperature and pressure in ammonium lactate decomposition reaction. The amino acid impurity contained in the fermented ammonium lactate as well as the unreacted ammonium lactate reduced the acid strength of Amberlyst-36, which resulted in the final ethyl lactate yield.  相似文献   
4.
Titanium has the ability to withstand extremely high seawater velocities with negligible corrosion. The inherent passive nature of the metal favours the attachment of bio-organisms more. In this paper the biofouling characteristics and the influence of macrofouling on grade 2 titanium have been investigated in the Palk Bay waters of Mandapam (India) over a period of a year.This work comprises both field exposure as well as laboratory studies. The deposits on titanium were analyzed with the XRD technique. Green algae such as Cladophorapsis zoolengeri, Cheatomorpha area, Chlorodesmis hillibrandii, Enteromorpha intestinalis, Cladophora species and red algae species of Hypnea valentiae, and animals such as bryozoans and barnacles 4 mm in size were identified on the titanium metal surface. The effect of macrofouling on corrosion of titanium was investigated by both impedance and polarization techniques. Titanium experienced negligible corrosion in seawater exposure with an appreciable fouling load of 0.4527 kg.m−2y−1.  相似文献   
5.
6.
MoO3/SiO2 composite with varying amounts of MoO3 loading (1–20 wt.%) were prepared by sol–gel method and calcined at 500 °C. These catalysts were employed for the liquid phase condensation of anisole with paraformaldehyde. All the catalysts were characterized by N2 sorption, XRD, and NH3-TPD. The activities of synthesized MoO3/SiO2 catalysts were compared with p-toluene sulfonic acid (p-TSA), the most frequently used catalyst for the condensation reactions, and with a supported metal oxide (WO x /ZrO2). Under the similar reaction conditions, synthesized 10 wt.% MoO3/SiO2 catalyst calcined at 500 °C was found to be the most active in the condensation of anisole with paraformaldehyde.  相似文献   
7.
Tyrosine sulfation is a posttranslational modification involved in the synthesis, secretion, and biological activity of proteins and peptides. Our previous studies have demonstrated that the enzyme activity was induced by ethanol. In the present work, the induction was studied in detail. Initial experiments were conducted to examine the time course of tyrosylprotein sulfotransferase (TPST) induction in rats pair-fed liquid diets containing either ethanol or carbohydrate substitute (controls). Marked elevation of TPST activity (3-fold) was measured on day 10 in the liver and gastric mucosa of ethanol-fed rats. Ethanol-mediated enhancement was also noticed by Western-blot analysis with anti-TPST antibody in both the liver and gastric mucosa on days 5 and 10. We then determined the steady-state TPST protein turnover in ethanol-fed and control animals that were given 35S-methionine after 10 days of pair-feeding with liquid diet. The rates of TPST synthesis assessed by measuring initial rates of incorporation of 35S-methionine into TPST was increased in the liver and gastric mucosa of animals fed with ethanol. Monophasic exponential decay curves showed that TPST protein half-lives for liver (control: 34 hr, ethanol: 32 hr) and gastric mucosa (control: 52 hr, ethanol: 48 hr) did not differ between control and ethanol groups. Our overall results indicate that the in vivo induction of TPST by ethanol involves increased enzyme synthesis rather than decreased enzyme degradation.  相似文献   
8.

In recent years, telecommunication is progressed due to the development of Long-Term Evolution (LTE) standards. This LTE network provides high-speed wireless communication for mobile devices and satisfies the requirements of customers from multi-cells. However, due to the congestion of mobile devices, each cell in the network may get overloaded. So, load balancing is the main challenge to the LTE network for reducing congestion or load in the cell. For load balancing, the optimal cell selection method is presented in this paper. Initially, the load factor of each cell is estimated. Then the load factor is compared with the predefined threshold load value. After the comparison, the heavy loaded cell handover the users to the optimal cell or cell with minimum load. This optimal cell is selected with the Opposition Based Artificial Flora (OAF) algorithm. Simulation results show that the proposed approach decreases 6% of the call blocking ratio (CBR) and 14% of Call Dropping Ratio (CDR) than the previous approaches.

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9.
Epoxy-polyamide coatings are used to protect metallic substrates in corrosive atmosphere. Thermal stability of the coating can be improved by the addition of inorganic cross-linking agent. Epoxy resin is incorporated with small percentage of silicone resin and cured with two types of hardeners such as polyamide and butyl titanate. The physical properties, heat resistance properties and electrochemical impedance behaviour of these coatings on steel in 0.5 M NaCl solution have been studied. The result implies that the heat resistant character of the titanate-cured coating is increased from 260 to 370 °C. The impedance study has shown that the coating resistance exerted by both the systems is in the range of 105 Ω cm2 after 6 days of immersion in 0.5 M NaCl. FTIR and Raman spectroscopy analysis confirm the presence of titanate linkage in the cured polymer coating. Thermal stability data indicate that the epoxy silicone resin cured with titanate hardener possesses higher thermal stability than that cured by polyamide hardener.  相似文献   
10.
We report the electropolymerization of 2-amino-1,3,4-thiadiazole (ATD) on glassy carbon (GC) and indium tin oxide (ITO) electrodes in 0.10 M H2SO4. The electropolymerized ATD (p-ATD) film was characterized by cyclic voltammetry, attenuated total reflectance (ATR)-FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The AFM image showed that the p-ATD formed a spherical-like structure with a thickness of 25 nm. XPS of the p-ATD film showed binding energies at 398.7, 400.3 and 401.3 eV in the N 1s region corresponding to –N, –NH– and –N+H–, respectively, and at 285.5 and 287.0 eV in the C 1s region corresponding to C–N and CN, respectively. The appearance of binding energies at 285.5 and 287.0 eV confirmed that the p-ATD film proceeded via C–N and CN linkages and not via C–C or CC linkages. The p-ATD film deposited on the GC electrode was successfully used for the determination of ascorbic acid (AA) at physiological pH. The amperometric current was increased linearly from 7.5 × 10−8 to 2.0 × 10−5, and the detection limit was found to be 0.28 nM (S/N = 3).  相似文献   
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