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排序方式: 共有257条查询结果,搜索用时 15 毫秒
1.
Masoud Haveshki Mahboobeh Mohamadhasani 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(12):2165-2173
The notion of extended filter of a filter associated to a subset of Rl-monoids is defined and related properties are investigated. Rachunek and Salounova proved that positive implicative filters and Boolean filters in Rl-monoids coincide with a condition in Rachunek and Salounova (Acta Univ Palacki Olomuc Fac rer nat Math 48(1):93–107, 2009). In this paper, we prove that positive implicative filters and Boolean filters coincide without any condition and get some results on various types of filters. 相似文献
2.
We have estimated the turnover and relative pool sizes of nascent-VLDL-TG and VLDL-remnants-TG in anesthetized rats. [1-14C]Palmitoyl- and [2-3H]glyceryl-labeled “VLDL”-TG (including nascent VLDL-TG and VLDL-remnants-TG) were prepared by injecting labeled palmitate and glycerol into donor rats. Labeled serum from these rats was then injected intravenously into nembutalized male rats and serial blood samples taken for 30 min. Special care was taken to define any early components in the labeled “VLDL”-TG disappearance curves. In other experiments, the donors were rendered functionally hepatectomized 30 min after injection of3H-glycerol and the endogenous labeled VLDL-TG was allowed to circulate 30–60 min before collection of the TG-labeled VLDL-remnants-containing serum. The latter was injected into 4 recipient nembutalized rats and the remnant-TG-turnover measured by serial sampling as above. In two cases,14C-“VLDL” and3H-VLDL-remnants were injected as a single bolus into ether-anesthetized rats. Despite its complex composition, “VLDL”-TG in most cases disappeared in a single exponential fashion for 30 min with an average half-life of 5.9 min in nembutalized and 2.8 in ether-anesthetized rats. VLDL-remnants-TG showed a more complex behavior, but contained a major rapid component with a mean t1/2 of ca. 1.5 min in both groups. The data, analyzed by multicompartmental analysis, were fitted to a simple model in which turnover of a larger nascent VLDL-TG pool with formation of a more rapidly turning over smaller pool of VLDL-remnant-TG is the rate-limiting step in overall TG removal from the d<1.006 fraction of rat serum. The data are consistent with our theoretical prediction that under these conditions the kinetics of the VLDL-remnants cannot be resolved from analysis of the total composite “VLDL” (nascent plus remnant) pool. 相似文献
3.
Peer-to-peer (P2P) networks are beginning to form the infrastructure of future applications. Computers are organized in P2P overlay networks to facilitate search queries with reasonable cost. So, scalability is a major aim in design of P2P networks. In this paper, to obtain a high factor of scalability, we partition network search space using a consistent static shared upper ontology. We name our approach semantic partition tree (SPT). All resources and queries are annotated using the upper ontology and queries are semantically routed in the overlay network. Also, each node indexes addresses of other nodes that possess contents expressible by the concept it maintains. So, our approach can be conceived as an ontology-based distributed hash table (DHT). Also, we introduce a lookup service for the network which is very scalable and independent of the network size and just depends on depth of the ontology tree. Further, we introduce a broadcast algorithm on the network. We present worst case analysis of both lookup and broadcast algorithms and measure their performance using simulation. The results show that our scheme is highly scalable and can be used in real P2P applications. 相似文献
4.
Kh. R. Rostami 《Instruments and Experimental Techniques》2016,59(2):273-277
Based on two Hall transducers, a low-frequency magnetometer with a sensitivity of 2.5 × 10–3 G/Hz1/2 is designed. The dynamic range of the magnetometer at a frequency of 19 Hz varies from 2.5 × 10–3 to ±8 × 104 G. 相似文献
5.
This study investigated the effect of solubility of amphiphilic compounds of acidic crude oil in water on the surface and interfacial tension (IFT) with NaCl, MgCl2, CaCl2, and Na2SO4 salts. Accordingly, distilled water, along with the salts mentioned in zero ionic strength up to 2 mol were put in contact with crude oil to become saturated with amphiphilic compounds. The effects of these compounds were investigated on the properties of contact water by pH, total organic carbon (TOC), FTIR (Fourier transform infrared spectroscopy), water-air surface tension (ST), and water-n-decane IFT tests. The results showed that some of the organic components of crude oil, especially acidic and basic compounds, are present or soluble in water, which have a significant effect on reducing the surface and IFT. The IFT reduction of water-n-decane was greater than the water-air ST system. Also, the observations showed that for both NaCl and Na2SO4 salt water, with increasing ionic strength of water, there was an optimum salinity within the range of 0.1-0.25 mol/L for both salts with the amount of surface and IFT minimized at this point. In the other two salts, this point was delayed upon elevation of ionic strength and was observed at high salinity. In this case, divalent cations reduce tension rate compared to monovalent cations. Due to solubility of acidic and basic groups in water, pH of salt water illustrates an acidic trend. Results of the FTIR test confirmed solubility of these compounds as well. 相似文献
6.
7.
Farshid Hassanzadeh Sahar Maaleki Jaleh Varshosaz Ghadam Ali Khodarahmi Maryam Farzan Mahboubeh Rostami 《Iranian Polymer Journal》2016,25(11):967-976
A novel thermosensitive folic acid (FA)-targeted succinylated poly (ethylene-co-vinyl alcohol) (EVOH) (EVOHS-FA) nanocarrier was synthesized for the specific delivery of epirubicin (EPI) to MCF-7 breast cancer cell line. Three different ratios of synthesized EVOH-Suc were reacted with FA. The structure of the desired products (EVOHS40-FA, EVOHS60-FA and EVOHS80-FA) was confirmed by 1H NMR and FTIR techniques. Nanoparticles were obtained by nano-precipitation procedure using DMSO/H2O as solvent/anti-solvent. The particle size, zeta potential, entrapment efficacy and in vitro release profile of the final formulations in different temperatures were measured. The optimized nanoparticles had the particle size of 214 ± 8.5 nm, zeta potential of ?29.6 mV, PDI of 0.198 ± 0.04, and a high encapsulation efficiency that released the drug efficiently within 450 h at the temperature of 40 °C compared to 37 °C. The morphology of nanoparticles was studied by scanning electron microscopy. The in vitro cytotoxicity was evaluated using the MTT assay on MCF-7 cell lines in response to temperatures of 37 and 40 °C. The MTT assay indicated that the targeted nanoparticles carrying EPI were significantly more cytotoxic than the non-targeted nanoparticles and the free drug at 40 °C. 相似文献
8.
Shadpour Mallakpour Mohammad Zhiani Abdolvahid Barati Hussein Rostami 《International Journal of Hydrogen Energy》2013
The present investigation deals with the fabrication of new poly(vinyl alcohol)/titanium dioxide (PVA/TiO2) nanocomposites (NCs) with different titanium dioxide (TiO2) loading by using ultrasound irradiation. For the improvement of nanoparticles (NPs) dispersion and increasing possible interactions between NPs and PVA, the surface of TiO2 NPs was modified by γ-aminopropyltriethoxy silane. The as-prepared NCs were characterized by spectroscopic, thermogravimetric analysis and electron microscopy methods. The results demonstrate that NPs dispersed homogeneously within the PVA matrix on nanoscale, which could be assigned to the hydrogen and covalent bonds formed between PVA and NPs. The results indicated that heat stability of NCs was improved in the presence of modified TiO2 NPs. The mechanisms of surface modification and a possible mechanism of ultrasonic induced interaction between polymer and NPs have been analyzed. 相似文献
9.
Fatemi Seyyed Amirasad Ahmadi Morteza Rostami Jamal 《Bulletin of Engineering Geology and the Environment》2018,77(2):501-513
Bulletin of Engineering Geology and the Environment - In recent years, anumber of models and formulas have been proposed to estimate the penetration rate of hard rock tunnel boring machines (TBMs).... 相似文献
10.