排序方式: 共有61条查询结果,搜索用时 16 毫秒
31.
Shadie Hatamie Mohammad Mahdi Ahadian Azam Iraji zad Omid Akhavan Effat Jokar 《Journal of the Iranian Chemical Society》2018,15(2):351-357
This paper reports on a novel low-temperature method for preparing curcumin-reduced graphene oxide (Cur-rGO) from graphene oxide (GO) and investigates their cyclic voltammetry (CV) and photoluminescence (PL) properties. GO sheets were synthesized using modified Hummers’ method and then were chemically reduced using polyphenol curcumin into graphene sheets. Atomic force microscopy, transmission electron microscopy and x-ray photoelectron spectroscopy were used to confirm the formation of Cur-rGO and revealed their functionalization with polyphenol curcumin. The electrochemical and optical properties of the Cur-rGO sheets were investigated using CV and PL spectroscopy. According to the PL and CV characterization for the Cur-rGO sheets, charges and resonant energy were transferred from curcumin molecules to the GO sheets’ surfaces. This arises from the bonding of the fluorescence curcumin molecules to the Cur-rGO surfaces, through π–π stacking of their aromatic rings. It should be noted that curcumin molecules act as electron donors, suppressing the fluorescence of the GO sheets while improving their electrochemical activities. 相似文献
32.
Borghei Sina Dehghanian Changiz Yaghoubi Rouhollah Yari Saeed 《Research on Chemical Intermediates》2016,42(5):4551-4568
Research on Chemical Intermediates - A new imidazoline derivative, {[(benzimidazol-2-ylmethyl)imino]bis(methylene)} bis(phosphonicacid), named as BMIBMBPA, was synthesized as an environmentally... 相似文献
33.
Olivier JH Barberá J Bahaidarah E Harriman A Ziessel R 《Journal of the American Chemical Society》2012,134(14):6100-6103
Red- and blue-absorbing boron dipyrromethene dyes, bearing opposite electronic charges, associate in solution to form a 1:2 complex having a stability constant of ca. 10(17) M(-2). The complex can be dismantled by addition of a large excess of tetra-N-butylammonium cations. The same complex displays liquid crystalline properties on heating from rt to above 150 °C, as characterized by various experimental techniques. Highly efficient electronic energy transfer from the red to the blue dye occurs in both the initial complex and the subsequent mesomorphic state. 相似文献
34.
Mitra Ghassemzadeh Samira Bahemmat Masoomeh Mahmoodabadi Babak Rezaii-Rad Hassan Hosseini Monfared Effat Mottefakeri Bernhard Neumüller 《Polyhedron》2010
The reaction of AMTT (AMTT = 4-amino-3-methyl-1,2,4-triazol-5-thione, HL1) with palladium(II) chloride and triphenylphosphane as a co-ligand in acetonitrile afforded the mononuclear PdII-complex [(PPh3)Pd(HL1)Cl]Cl·2CH3CN (1). The complex [(PPh3)Pd(HL1)I]Cl·1/2H2O (2) was prepared via halogen exchange between 1 and sodium iodide in methanol/acetonitrile. The first binuclear palladium(II) complex containing singly deprotonated HL1, [(PPh3)2ClPd(L1)Pd(PPh3)Cl]Cl·1/3H2O·CH3OH (3), was prepared by the reaction of HL1 with palladium(II) chloride and triphenylphosphane in the presence of sodium acetate in methanol. 相似文献
35.
Effat Golpar-Raboky 《Linear and Multilinear Algebra》2013,61(12):1641-1659
We present an integer rank reduction formula for transforming the rows and columns of an integer matrix A. By repeatedly applying the formula to reduce rank, an extended integer rank reducing process is derived. The process provides a general finite iterative approach for constructing factorizations of A and A T under a common framework of a general decomposition V T AP?=?Ω. Then, we develop the integer Wedderburn rank reduction formula and its integer biconjugation process. Both the integer biconjugation process associated with the Wedderburn rank reduction process and the scaled extended integer Abaffy–Broyden–Spedicato (ABS) class of algorithms are shown to be in the integer rank reducing process. We also show that the integer biconjugation process can be derived from the scaled integer ABS class of algorithms applied to A or A T . Finally, we show that the integer biconjuagation process is a special case of our proposed ABS class of algorithms for computing the Smith normal form. 相似文献
36.
Effat Souri Zahra Kargar Shahrooz Saremi Nazanin Shabani Ravari Farhad Alvandifara Massoud Amanloua 《中国化学会会志》2011,58(4):443-449
The aim of this study was to study the stress degradation of granisetron and analysis of the drug in the presence of its degradation products. Forced degradation studies were conducted on bulk sample using acidic, alkaline, oxidative, heat and photolytic conditions. Granisetron was relatively unstable under acidic, alkaline and oxidative conditions. Separation of granisetron and degradation products was achieved using a Nova‐Pak C8 column and acetonitrile‐KH2PO4 25 mM (75:25, v/v) as mobile phase with UV detection at 305 nm. The method was linear over the range of 0.2‐15 μg/mL granisetron (r2 > 0.999). The within‐day and between‐day precision values were also in the range of 0.5‐4%. The proposed method was successfully applied for quantitative determination of granisetron in tablets and in vitro dissolution studies. 相似文献
37.
Iman R. MafiChangiz Dehghanian 《Applied Surface Science》2011,257(20):8653-8658
The effects of the addition of three types of surfactants (cationic, anionic, non-ionic) at different concentrations in the plating bath on the deposition rate, PTFE content and surface morphology of electroless Ni-P/PTFE composite coatings were investigated. It was demonstrated that the cationic and non-ionic surfactants created a uniform distribution of PTFE particles in the coatings. The effects of the surfactant type and concentration on the corrosion properties of Ni-P/PTFE coatings were also studied. The corrosion resistance was increased by the incorporation of PTFE particles into the Ni-P matrix. The level of improvement depended largely on the type and concentration of the applied surfactants. 相似文献
38.
Ceramic oxide coatings (titania) were produced on Ti by micro-arc oxidation in different aluminate and carbonate based electrolytes. This process was conducted under constant pulsed DC voltage condition. The effect of KOH and NaF in aluminate based solution was also studied. The surface morphology, growth and phase composition of coatings were investigated using scanning electron microscope and X-ray diffraction. Corrosion behavior of the coatings was also examined by potentiodynamic polarization and electrochemical impedance spectroscopy. It was found that the sparking initiation voltage (spark voltage) had a significant effect on the form and properties of coatings. Coatings obtained from potassium aluminate based solution had a lower spark voltage, higher surface homogeneity and a better corrosion resistance than the carbonate based solution. Addition of NaF instead of KOH had improper effects on the homogeneity and adhesion of coatings which in turn caused a poor corrosion protection behavior of the oxide layer. AC impedance curves showed two time constants which is an indication of the coatings with an outer porous layer and an inner compact layer. 相似文献
39.
Mozhde Bagheri Hosseini Farzad Dehghanian Majid Salari 《European Journal of Operational Research》2019,272(2):655-673
This paper addresses a generalization of the capacitated location-routing problem (CLRP) arising in the design of a collection network for a company engaged in collecting used products from customer zones. The company offers customers a financial incentive per unit of used products. This incentive determines the quantity of used products which are returned by customers. Moreover, it is not necessary for the company to visit all customer zones or to collect all returns in each visited customer zone. The objective is to simultaneously find the location of collection centers, the routes of vehicles, the value of incentive offered and the amount of used products collected from customer zones, so as to maximize the company's overall profit. We develop two mixed integer linear programming formulations of the problem and a heuristic algorithm based on iterated local search. Extensive computational experiments on this problem demonstrate the effectiveness of the proposed algorithm. 相似文献
40.
The aim of this work is to discuss the growth characteristics and corrosion behavior of the prepared ceramic coatings on titanium by plasma electrolytic oxidation (PEO) technique in different electrolytes. PEO process was carried out on titanium under constant voltage regime using a pulse power supply. Three kinds of electrolytes, phosphate, silicate and borate based solutions, were used to evaluate the influence of electrolyte composition on the structure, surface morphology, phase composition and corrosion behavior of prepared ceramic oxide films (titania). The phase composition of the coatings was investigated by X-ray diffraction. Scanning electron microscopy was employed to evaluate the growth and surface morphology of coatings. Elements of coatings were investigated with energy dispersive spectrometer. Corrosion behavior of the coatings was also examined by potentiodynamic polarization and electrochemical impedance spectroscopy. The spark voltage of oxide films had a significant effect on the surface morphology, size and homogeneity of micro-pores, thickness and corrosion properties of coatings. 相似文献