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21.
本项目由Open-Silicon,GLOBALFOUNDRI ES和Amkor三家公司合作完成。两颗28nm的ARM处理器芯片,通过2.5D硅转接板实现集成。芯片的高性能集成通常由晶体管制程提高来实现,应用2.5D技术的Si P正成为传统芯片系统集成的有效替代。Open-Silicon负责芯片和硅转接板的设计,重点在于性能优化和成本降低。GLOBALFOUNDRI ES采用28nm超低能耗芯片工艺制造处理器芯片,而用65nm技术制造2.5D硅转接板。包括功耗优化和功能界面有效管理等概念得到验证。硅基板的高密度布线提供大量平行I/O,以实现高性能存储,并保持较低功耗。所开发的EDA设计参考流程可以用于优化2.5D设计。本文展示了如何将大颗芯片重新设计成较小的几颗芯片,通过2.5D硅转接板实现Si P系统集成,以降低成本,提高良率,增加设计灵活性和重复使用性,并减少开发风险。  相似文献   
22.
The spherical mesoporous MCM-41 coated with a novel Ca2MoO5:Eu3+ phosphor layer was prepared for the first time. The obtained Ca2MoO5:Eu3+-MCM-41 was characterized via XRD and FT-IR. The crystal system of the Ca2MoO5 phase was determined to be orthorhombic, and its space group was found to be Ima2 (46), and its cell parameters were a = 16.175, b = 5.1514, c = 5.6977 A°; α = β = γ = 90°. The particle dimensions of MCM-41 and Ca2MoO5:Eu3+-MCM-41 nanoparticles were determined to be 260 nm and 229 nm via scanning electron microscopy analysis. Bortezomib was loaded into the Ca2MoO5:Eu3+-MCM-41 nanoparticles under scCO2 at 200 bars and 40 °C. The results of the TG analysis showed that the amount of drug-loaded to MCM-41 and Ca2MoO5:Eu3+-MCM-41 nanoparticles were determined to be 14.02% and 3.02%, respectively. The BET analysis showed that while the specific surface area and pore volume of MCM-41 and Ca2MoO5:Eu3+ before Bortezomib (BTZ) loading were 1,506 m2/g and 267 m2/g, respectively, after drug loading these values were found to decrease to 488 m2/g and 7.883 m2/g. It was determined that BTZ was released from the nanoparticles in a sustained manner over 66 h. The R2 value, which was calculated to be 0.9739, indicated that the release kinetic of BTZ followed the Korsmeyer–Peppas model.  相似文献   
23.
Carbene transfer to appropriate substrates is a highly versatile tool for the construction of carbon frameworks with increased functional and structural complexity. In this study, some novel cyclopropane derivatives were synthesized via carbenoid reactions and their further reactivities were investigated. (1E)‐Buta‐1,3‐dien‐1‐yl acetate was reacted with four different diazocarbonyl compounds, ethyl diazoacetate, dimethyl diazomalonate, 1‐diazo‐1‐phenylpropan‐2‐one, and methyl (3E)‐2‐diazo‐4‐phenylbut‐3‐enoate, in the presence of two catalysts. All synthesized substituted cyclopropanes were obtained chemoselectively with respect to less‐hindered C?C bonds. Under the applied conditions, while cyclopropanes 7a and 7d underwent further reactions, cyclopropanes 7b and 7c were stable enough. Cyclopropanes 7a and an additional equivalent of ethyl diazoacetate yielded polyfunctionalized cyclohexenes. Cyclopropanes from methyl (3E)‐2‐diazo‐4‐phenylbut‐3‐enoate yielded polyfunctionalyzed cycloheptadiene isomers by Cope rearrangement.  相似文献   
24.
Güngör N  Ozyürek M  Güçlü K  Cekiç SD  Apak R 《Talanta》2011,83(5):1650-1658
Thiol-type compounds are an important class of strong antioxidants and main determinants of total antioxidant capacity (TAC) of cellular homogenates. The TAC of thiol mixtures and the corresponding TEAC (trolox equivalent antioxidant capacity) values of individual thiols were determined by the CUPRAC (CUPric Reducing Antioxidant Capacity) method, and the results were compared with those found by reference assays for method validation. Synthetic mixtures of thiols were prepared, and the expected and found TAC values (in mM trolox (TR) equivalents) of these mixtures showed a good agreement. The technique of standard additions was performed for thiol mixtures and human serum, and the absorbance results confirmed that apparent chemical deviations from Beer's law were absent in the system. The CUPRAC results were compared with those of reference methods, namely 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)/persulphate and Ferric Reducing Antioxidant Power (FRAP). As being a most important thiol (-SH) peptide at in vivo conditions, glutathione (GSH) showed a TEAC value of 0.57 in the CUPRAC method, as opposed to the corresponding value (1.51) in the ABTS/persulphate method. The ABTS/persulphate result was not in accordance with the reversible 1-e oxidation of GSH to the corresponding disulfide that is expected to occur under physiological conditions. FRAP did not give consistent results, and even at relatively high concentrations of GSH, the TEACFRAP value was only 0.07. The thiol-type antioxidant-bearing pharmaceuticals of Brunac eye drop, Trom and Mentopin effervescent tablets containing N-acetyl-l-cysteine (NAC) were assayed with HPLC for comparison, and the obtained results for NAC were in accordance with those found with CUPRAC.  相似文献   
25.
The Blume-Capel model in the presence of external magnetic field H has been simulated using a cellular automaton algorithm improved from the Creutz cellular automaton in three-dimension lattice. The field critical exponent 5 is estimated using the power law relations and the finite size scaling functions for the magnetization and the susceptibility in the range -0.1≤ h = H/J ≤0. The estimated value of the field critical exponent 5 is in good agreement with the universal value (δ = 5) in three dimensions. The simulations are carried out on a simple cubic lattice under periodic boundary conditions.  相似文献   
26.
In this study, a method of analysis is presented for investigating the effects of elastic foundation and fluid on the dynamic response characteristics (natural frequencies and associated mode shapes) of rectangular Kirchhoff plates. For the interaction of the Kirchhoff plate–Pasternak foundation, a mixed-type finite element formulation is employed by using the Gâteaux differential. The plate finite element adopted in this study is quadrilateral and isoparametric having four corner nodes, and at each node four degrees of freedom are present (one transverse displacement, two bending moments and one torsional moment). Therefore, a total number of 16 degrees-of-freedom are assigned to each element. A consistent mass formulation is used for the eigenvalue solution in the mixed finite element analysis. The plate structure considered is assumed clamped or simply supported along its edges and resting on a Pasternak foundation. Furthermore, the plate is fully or partially in contact with fresh water on its one side. For the calculation of the fluid–structure interaction effects (generalized fluid–structure interaction forces), a boundary element method is adopted together with the method of images in order to impose an appropriate boundary condition on the fluid's free surface. It is assumed that the fluid is ideal, i.e., inviscid, incompressible, and its motion is irrotational. It is also assumed that the plate–elastic foundation system vibrates in its in vacuo eigenmodes when it is in contact with fluid, and that each mode gives rise to a corresponding surface pressure distribution on the wetted surface of the structure. At the fluid–structure interface, continuity considerations require that the normal velocity of the fluid is equal to that of the structure. The normal velocities on the wetted surface of the structure are expressed in terms of the modal structural displacements, obtained from the finite element analysis. By using the boundary integral equation method the fluid pressure is eliminated from the problem, and the fluid–structure interaction forces are calculated in terms of the generalized hydrodynamic added mass coefficients (due to the inertial effect of fluid). To asses the influences of the elastic foundation and fluid on the dynamic behavior of the plate structure, the natural frequencies and associated mode shapes are presented. Furthermore, the influence of the submerging depth on the dynamic behavior is also investigated.  相似文献   
27.
Abstract

Some new 3,4,5-trisubstituted 1,2,4-triazole derivatives were synthesized and studied for their antimicrobial activity. The lead compounds were obtained starting from 8-hydroxyquinoline and ethyl 2-chloroacetate. The obtained ester compound (1) first reacted with hydrazine hydrate (2) then with phenyl isothiocyanate (3). Ring closure by KOH led to 3-mercapto-1,2,4-triazole derivative (4). Lastly, it reacted with 2-chloro-N-(substituted (benzo)/thiazole)acetamide derivatives to obtain the final compounds (5a–j). The structural elucidation of the compounds was performed by 1H NMR and 13C NMR spectroscopy and high resolution mass spectrometry techniques and elemental analysis. The synthesized compounds were investigated for their antimicrobial activities against seven bacteria and four fungi. As a result of the activity studies, it was observed that compounds N-(6-nitrobenzothiazol-2-yl)-2-[[4-phenyl-5-((quinolin-8-yloxy)methyl)-4H-1,2,4-triazol-3-yl]thio]acetamide (5a) and N-(6-fluorobenzothiazol-2-yl)-2-[[4-phenyl-5-((quinolin-8-yloxy)methyl)-4H-1,2,4-triazol-3-yl]thio]acetamide (5d) were the most active molecules. Also, the antifungal activity of the compounds was found to be higher than their antibacterial activity although lower than the standard drug’s potential. Additionally, the physicochemical properties of the compounds were calculated which were evaluated to be at a suitable range for oral administration.  相似文献   
28.
ABSTRACT

The simple cubic spin-1 Ising model exhibits the ferromagnetic (F)–ferromagnetic (F) phase transition in the low temperature region for the interval 1.40 < d = D/J < 1.48 at k = K/J = –0.5. The degree of the F-F phase transition determines the special point on the (kBT/J, d) phase diagram. In this paper, the critical behavior of the F-F phase transition was investigated for different heating rates using the cellular automaton heating algorithm. The universality class and the type of F-F phase transition were analyzed using the finite-size scaling theory and the power law relations. The results show that the F-F phase transition may be the second order, the first order or the weak first order depending on the heating rate in the interval 1.40 < d < 1.48 for k = –0.5.  相似文献   
29.
Reactive oxygen species (ROS) may attack biological macromolecules giving rise to oxidative stress-originated diseases, so it is important to establish efficient methods to screen hydroxyl radical scavengers for antioxidant therapy. Since *OH is very short-lived, secondary products resulting from *OH attack to various probes are measured. As a low-cost measurement technique, we used a salicylate probe for detecting hydroxyl radicals generated from an equivalent mixture of Fe(II)+EDTA with hydrogen peroxide. The produced hydroxyl radicals attacked both the probe and the water-soluble antioxidants in 37 degrees C-incubated solutions for 2 h. The CUPRAC (cupric ion reducing antioxidant capacity) assay absorbance of the ethylacetate extract due to the reduction of Cu(II)-neocuproine reagent by the hydroxylated probe decreased in the presence of *OH scavengers, the difference being proportional to the scavenging ability of the tested compound. Attack by *OH radicals upon salicylate produced 2,3-dihydroxybenzoate, 2,4-dihydroxybenzoate, and 2,5-dihydroxybenzoate as major products. HPLC separation combined with CUPRAC spectrophotometry was used to identify and quantify hydroxylated salicylate derivatives in the presence of synthetic water-soluble antioxidants and green tea infusion. The developed spectrophotometric method for *OH detection was validated with HPLC, i.e., the concentrations of dihydroxybenzoates produced by radical attack from the probe were determined by HPLC, and the sum of (concentrationxabsorptivity) products of these components approximately agreed with the experimentally found CUPRAC absorbances, confirming the validity of Beer's law for the selected system. Statistical comparison of the results found with the proposed methodology and HPLC was made with two-way ANOVA (analysis of variance) test. Under optimal conditions, about 53% of the probe (salicylate) was converted into dihydroxybenzoate isomers in the absence of *OH scavengers, and these isomers were more specific markers of hydroxyl radicals than the non-specific malondialdehyde end-product of the TBARS test. Thus, the more costly and less speedy HPLC method could advantageously be substituted with the proposed spectrophotometric assay of *OH detection, which was also of much higher yield than the TBARS colorimetric assay.  相似文献   
30.
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