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321.
322.
Rasekholghol Ariam Fazaeli Yousef Moradi Dehaghi Shahram Ashtari Parviz 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):599-608
Journal of Radioanalytical and Nuclear Chemistry - Radiolabeled fluorescent nanocomposite, 68Ga@CdTeQDs@SH-Propyl@MCM-41, was prepared. The prepared material was characterized using X-ray... 相似文献
323.
Ab initio (RHF/STO-3G) quantum chemical calculations using the self-consistent reaction field (SCRF) model were carried out to analyze
the effect of solvent polarity on the relative Gibbs free energies, the dipole moments, and the structural stability of peptide
macrocycles based on unsubstituted cyclo[Gly6] and its trisubstituted derivatives containing Me, NH2, or OH groups at the Cα atom. The macrocycles studied are stable in water at both room temperature and at body fever temperature,
which is important for the design of a stable nanovehicle for drug delivery in water. 相似文献
324.
Zahra Tajbakhsh Parviz Fattahi Javad Behnamian 《The Journal of the Operational Research Society》2014,65(10):1580-1592
This study is devoted to schedule a three-stage manufacturing system including machining, assembly and batch processing stages. The system is supposed to be capable of manufacturing a variation of products. At the first stage, the need for machining raw parts causes the manufacturer to deal with a flow shop scheduling problem. In the next stage, processed parts should be assembled together in order to form desired products. It is noteworthy that several operations are not allowed to be executed simultaneously on the same machine. Second stage should be considered as a single-assembly line or a single team of operators, and finally the manufacturing processing stage. The considered objectives are to minimize completion time of all products (makespan) and sum of the earliness and tardiness costs, simultaneously. First, the proposed scheduling problem is formulated into a mixed-integer mathematical model, and then owing to the NP-hardness of the concluded model a meta-heuristic approach is applied. A hybrid algorithm is modified to create a powerful method in searching the discrete solution space of this problem by taking advantage of superiorities of both Genetic Algorithm and Particle Swarm Optimization methods. Numerical experiments are designed to evaluate the performance of the proposed algorithm. 相似文献
325.
Marjan Motiei Luis Pleno de Gouveia Tom opík Robert Vícha David koda Jaroslav Císa Reza Khalili Eva Domincov Bergerov Luk Münster Haojie Fei Vladimír Sedlaík Petr Sha 《Molecules (Basel, Switzerland)》2021,26(7)
The alkaline milieu of chronic wounds severely impairs the therapeutic effect of antibiotics, such as rifampicin; as such, the development of new drugs, or the smart delivery of existing drugs, is required. Herein, two innovative polyelectrolyte nanoparticles (PENs), composed of an amphiphilic chitosan core and a polycationic shell, were synthesized at alkaline pH, and in vitro performances were assessed by 1H NMR, elemental analysis, FT-IR, XRD, DSC, DLS, SEM, TEM, UV/Vis spectrophotometry, and HPLC. According to the results, the nanostructures exhibited different morphologies but similar physicochemical properties and release profiles. It was also hypothesized that the simultaneous use of the nanosystem and an antioxidant could be therapeutically beneficial. Therefore, the simultaneous effects of ascorbic acid and PENs were evaluated on the release profile and degradation of rifampicin, in which the results confirmed their synergistic protective effect at pH 8.5, as opposed to pH 7.4. Overall, this study highlighted the benefits of nanoparticulate development in the presence of antioxidants, at alkaline pH, as an efficient approach for decreasing rifampicin degradation. 相似文献
326.
Parviz Shahbazikhah John H. Kalivas Erik Andries Trevor O'Loughlin 《Journal of Chemometrics》2016,30(3):109-120
With projection based calibration approaches, such as partial least squares (PLS) and principal component regression (PCR), the calibration space is spanned by respective basis vectors (latent vectors). Up to rank k basis vectors are formed where k ≤ min(m,n) with m and n denoting the number of calibration samples and measured variables. The user needs to decide how many and which respective basis vectors (tuning parameters). To avoid the second issue, basis vectors are selected top‐down starting with the first and sequentially adding until model criteria are satisfied. Ridge regression (RR) avoids the issues by using the full set of basis vectors. Another approach is to select a subset from the total available. The presented work develops a process based on the L1 vector norm to select basis vectors. Specifically, the L1 norm is used to select singular value decomposition (SVD) basis set vectors for PCR (LPCR). Because PCR, PLS, RR, and others can be expressed as linear combination of the SVD basis vectors, the focus is on selection and comparison using the SVD basis set. Results based on respective tuning parameter selections and weights applied to the SVD basis vectors for LPCR, top‐down PCR, correlation PCR (CPCR), PLS, and RR are compared for calibration and calibration updating using spectroscopic data sets. The methods are found to predict equivalently. In particular, the L1 norm produces similar results to those obtained by the well‐studied CPCR process. Thus, the new method provides a different theoretical framework than CPCR for selecting basis vectors. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
327.
Khalil Farhadi Sepideh Banisaeid Arezu Jamali Hamid Zebhi Zahed Ghelichkhah Hedayat Khalili Robab Abbasi 《中国化学会会志》2015,62(12):1149-1154
Electrochemical polymerization of tyramine was achieved on copper electrode surface from tyramine in 0.3 M oxalic acid (pH=1.2) solution by using cyclic voltammetry technique. The formation of polytyramine nanoparicles (PTN) were characterized by cyclic voltammetry (CV), fourier transform infrared‐attenuated total reflectance (FTIR‐ATR) spectroscopy and scanning electron microscopy (SEM). The corrosion behavior of PTN coated copper was investigated by means of the change of open circuit potential with exposure time (Eocp t), electrochemical impedance spectroscopy (EIS) and anodic polarization curves in 3.5 % NaCl solutions at room temperature. The obtained results showed the shift of corrosion potential toward positive values for electropolymerized copper and a significant decrease in corrosion current and corrosion rate in comparison with bare copper, so that the PTNs coating could be used as an important protection against corrosion of copper. 相似文献
328.
The Design and Synthesis of Novel 2,3‐Dihydrobenzo[f]isoquinolin‐4(1H)‐ones via Sequential Ugi–Heck Reactions by Using an Efficient Heterogeneous Palladium Nanocatalyst 下载免费PDF全文
Mohammad Ali Rasouli Simin Miri Parviz Rashidi Ranjbar 《Journal of heterocyclic chemistry》2015,52(6):1864-1870
A facile and efficient synthesis of N‐alkyl‐2‐(1, 2 dihydro‐1‐methylene‐4‐oxobenzo[f] isoquinoline‐3(4H)‐yl)‐2‐phenylacetamides is performed by the consecutive, two‐step procedure that consists of Ugi and Heck reactions. The Heck reaction was performed both by homogenous and a designed heterogeneous catalyst. The heterogeneous catalyst is a coordinated palladium to 1, 10‐phenanthroline attached to chitosan@Fe3O4 magnetite nanoparticles, which was shown to be more efficient than the homogenous Pd(OAc)2/PPh3 catalyst with good to excellent yields. 相似文献
329.
330.
Mojtaba Amini Sajjad Bahadori Tekantappeh Bagher Eftekhari-Sis Parviz Gohari Derakhshandeh Kristof Van Hecke 《Journal of Coordination Chemistry》2017,70(9):1564-1572
A copper-containing polyoxovanadate nanocluster, [(C2H5)4N]4[V8Cu2O24]?2H2O (1), was synthesized through reaction between the Cu(NO3)2?3H2O and [(C2H5)4N]4VO3 in the molar ratio 1?:?4. Nanocluster 1 was characterized by IR, elemental analysis, XRD, SEM, TEM, and X-ray crystallography. The catalytic activity of 1 for the azide–alkyne cycloaddition of different terminal alkynes and organic azides generated in situ from sodium azide and different organic halides was tested. The protocol could afford the corresponding products in good to excellent yield at very low catalyst loadings (3.4 Mol%) under the optimized reaction conditions. 相似文献