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排序方式: 共有158条查询结果,搜索用时 15 毫秒
101.
Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Naghmeh Sadat Mirbagheri 《Journal of organometallic chemistry》2010,695(17):2014-1368
In the present work, highly efficient epoxidation of alkenes catalyzed by Mo(CO)6 supported on amines modified multi-wall carbon nanotubes, MWCNTs, is reported. The prepared catalysts were characterized by elemental analysis, scanning electron microscopy, FT-IR and diffuse reflectance UV-Vis spectroscopic methods. These new heterogenized catalysts, [Mo(CO)6@amines-MWCNT], were used as highly efficient catalysts for epoxidation of alkenes with tert-BuOOH. These robust catalysts could be reused several times without loss of their catalytic activities. 相似文献
102.
Rash Saleh Rahma Sadat Magda Kassem 《Mathematical Methods in the Applied Sciences》2020,43(4):1775-1787
We explored and specialized new Lie infinitesimals for the (3 + 1)-dimensional B-Kadomtsev-Petviashvii (BKP) using the commutation product, which results a system of nonlinear ODEs manually solved. Through two stages of Lie symmetry reduction, (3 + 1)-dimensional BKP equation is reduced to nonsolvable nonlinear ODEs using various combinations of optimal Lie vectors. Using the integration and Riccati equation methods, we investigate new analytical solutions for these ODEs. Back substituting to the original variables generates new solutions for BKP. Some selected solutions illustrated through three-dimensional plots. 相似文献
103.
Zahra Sadat Aghayan Alireza Alfi J. A. Tenreiro Machado 《Mathematical Methods in the Applied Sciences》2020,43(17):10332-10345
This article investigates the robust stability of fractional order neutral-type systems involving nonlinear perturbations and time varying delays in the presence of input saturation. Design criteria, expressed in terms of linear matrix inequalities, are derived with the aid of the Lyapunov Krasovskii functional for the state feedback controller. Based on the cone complementarity linearization method, an optimization problem is also formulated for finding the controller gains subject to maximizing the domain of attraction. The main results are confirmed by numerical simulations. 相似文献
104.
Elham Sadat Taheri Mohsen Jahanshahi Mohammad Taghi Hamed Mosavian 《Particle & Particle Systems Characterization》2012,29(3):211-222
Protein nanoparticles have been recognized as carriers to deliver low molecular‐weight drugs, anticancer drug, DNA, vaccines, oligonucleotides, peptides and etc. The purpose of this research was preparation of Egg Albumin (EA) nanoparticle with suitable size/size distribution and good surface properties for drug delivery application based on simple coacervation method along with optimization of the nanoparticles by employing Taguchi method. Several synthesis parameters were examined to characterize their impacts on nanoparticle size and topography. These variables were including temperature, EA concentration, desolvating agent volume, pH value and agitation speed. In addition, size and morphology of prepared nanoparticles were analyzed by photon correlation spectroscopy (PCS) as well as atomic force microscopy (AFM). As result of Taguchi analysis in this research, desolvating agent volume and pH were most influencing factors on particle size. The minimum size of nanoparticles (~51 nm) were obtained at Temperature 55 °C, 30 mg/ml EA concentration, desolvating agent volume 50 ml, agitation speed of 500 rpm and pH 4. The mechanistic of optimum conditions for preparing protein nanoparticles from Egg Albumin for the first time and their characterization as delivering nano system are discussed. 相似文献
105.
N. Sadeghzadeh M. Gandomkar R. Najafi M. Shafiei S. E. Sadat Ebrahimi A. Shafiee B. Larijani 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(1):181-187
A variety of human tumors like prostate and breast cancer express bombesin receptors. Due to this a new bombesin analogue
was labeled with 99mTc via HYNIC and tricine as a coligand and investigated further. Peptide was synthesized on a solid phase using Fmoc strategy.
Labeling with 99mTc was performed at 100 °C for 10 min and radiochemical analysis involved ITLC and HPLC methods. The stability of radiopeptide
was checked in the presence of human serum at 37 °C up to 24 h. Internalization was studied with the human GRP receptor cell
line PC-3. The biodistribution was studied in mice. Labeling yield of >98% was obtained corresponding to a specific activity
of ~80.9 GBq/μmol. Radiopeptide internalization into PC-3 cells was moderate and specific (10.7 ± 1.2% at 4 h). A high and
specific GRP receptor expressing mouse tumor and pancreas uptake (1.12 ± 0.08 and 1.04 ± 0.11% ID/g after 1 h respectively)
was also determined. 相似文献
106.
Seyedi Maryam Sadat Sohrabi Mahmoud Reza Motiee Fereshte Mortazavinik Saeid 《Research on Chemical Intermediates》2020,46(3):1645-1662
Research on Chemical Intermediates - A simple and fast method based on activated carbon@nanozerovalent iron–nickel (AC@nZVI/Ni) nanoadsorbent was developed for highly efficient removal of... 相似文献
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Vahideh Sadat Abedi 《The Journal of the Operational Research Society》2017,68(2):134-146
We consider the allocation of a limited marketing budget between multiple channels in order to promote sales at multiple markets. The channels differ in their type, level of targetability (or reach), and costliness. We incorporate the “threshold effect” from each market in our resource allocation which requires some positive advertising investment in each market before much sales impact can be observed from it. The increased number of channels in recent years with the advent of digital advertising, along with the added complexity created by the threshold effect, necessitates the development of new allocation approaches. In this paper, we formulate the firm’s resource allocation decision as a nonlinear and nonseparable knapsack problem. We develop a branch and cut solution method which is enhanced by a heuristic approach. A set of numerical experiments illustrate the performance of our methods and evaluate the usefulness of two rule-of-thumb strategies commonly used in practice. 相似文献