Mohammad Hossein Keshavarz  Sahar Belyani  Seyyed Mohammad Reza Darbani  Masoud Kavosh Tehrani 《无机化学与普通化学杂志》2019,645(16):1057-1061

Laser Induced Breakdown Spectroscopy (LIBS) method is introduced as a novel approach in this work to study catalyst deactivation of V₂O₅/γ‐‐Al₂O₃ for gas‐phase dehydration of glycerol and producing acrolein. The LIBS results of V₂O₅/γ‐Al₂O₃ samples are compared with those data that are obtained by Inductively Coupled Plasma Optical Emission Spectrometry (ICP‐OES). Experimental data of LIBS data specify that line intensities of vanadium are decreased by deactivation of V₂O₅/γ‐Al₂O₃ catalyst. A comparison between the results of LIBS test as well as ICP‐OES analysis shows that the amount of vanadium is decreased in the catalyst. Moreover, coke formation changes the surface of the catalyst. The results of deactivation of V₂O₅/γ‐Al₂O₃ are also compared with Pd/C catalyst deactivation.  相似文献   

    

Seyyed Javad Sabounchei  Khadijeh Badpa  Mehdi Bayat  Roya Karamian  Fatemeh Ghasemlou  Robert W. Gable  Parviz Gohari Derakhshandeh  Kristof Van Hecke 《应用有机金属化学》2019,33(3)

The reaction of α‐keto‐stabilized diphosphine ylides [Ph₂P(CH₂)_nPPh₂═C(H)C(O)C₆H₄‐p‐CN] (n = 1 (Y¹); n = 2 (Y²)) with dibromo(1,5‐cyclooctadiene) palladium(II)/platinum(II) complexes, [Pd/PtBr₂(cod)], in equimolar ratio gave the new cyclometalated Pd(II) and Pt(II) complexes [Br₂Pd(κ²‐Y¹)] ( 1 ), [Br₂Pt(κ²‐Y¹)] ( 2 ), [Br₂Pd(κ²‐Y²)] ( 3 ) and [Br₂Pt(κ²‐Y²)] ( 4 ). These compounds were screened in a search for novel antibacterial agents and characterized successfully using Fourier transfer infrared and NMR (¹H, ¹³C and ³¹P) spectroscopic methods. Also, the structures of complexes 1 and 2 were characterized using X‐ray crystallography. The results showed that the P,C‐chelated complexes 1 and 2 have structures consisting of five‐membered rings, while 3 and 4 have six‐membered rings, formed by coordination of the ligand through the phosphine group and the ylidic carbon atom to the metal centre. Also, a theoretical study of the structures of complexes 1 – 4 was conducted at the BP86/def2‐SVP level of theory. The nature of metal–ligand bonds in the complexes was investigated using energy decomposition analyses (EDA) and extended transition state combined with natural orbitals for chemical valence analyses. The results of EDA confirmed that the main portions of ΔE_int, about 57–58%, in the complexes are allocated to ΔE_elstat.  相似文献   

    

Tracy E. Scott  Amin Khalili  Brandon Newton  Robert Warren  Daniel P. Browe  Joseph W. Freeman 《先进技术聚合物》2019,30(10):2604-2612

Hydrogels have been used for many applications in tissue engineering and regenerative medicine due to their versatile material properties and similarities to the native extracellular matrix. Poly (ethylene glycol) diacrylate (PEGDA) is an ionic electroactive polymer (EAP), a material that responds to an electric field with a change in size or shape while in an ionic solution, that may be used in the development of hydrogels. In this study, we have investigated a positively charged EAP that can bend without the need of external ions. PEGDA was modified with the positively charged molecule 2‐(methacryloyloxy)ethyl‐trimethylammonium chloride (MAETAC) to provide its own positive ions. This hydrogel was then characterized and optimized for bending and cellular biocompatibility with C2C12 mouse myoblast cells. Studies show that the polymer responds to an electric field and supports C2C12 viability.  相似文献   

    

Mostafaee  Amin  Sohraiee  Sevan 《Annals of Operations Research》2019,275(2):531-549

In this paper, the suspicious units including anchor, terminal, and exterior units are investigated as important subsets of vertex units. Based on the concept of separating hyperplanes, an alternative definition of vertex units in data envelopment analysis is presented. Moreover, an advanced mathematical model for obtaining the separating hyperplane that splits up a vertex unit from the other units is proposed. Utilizing the core concept of separating hyperplanes, the special geometry of terminal units enables us to introduce a new definition for terminal units. Thus, some theorems have been proved which provide necessary and sufficient conditions for obtaining terminal units. We made use of the concept of supporting hyperplanes to provide a basic definition for exterior units and present a careful model for discovering exterior units. Also, based on the concept of supporting hyperplanes, different definitions of anchor units have been represented. Finally, the relationship between the sets of exterior, terminal and anchor units have been demonstrated in a theorem.

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Paul  Soumyadeep  Roy  Sumit  Ghosh  Pradyumna  Faghihi Zarandi  Mohammad Amin  Cender  Thomas  Pillai  Krishna M. 《Transport in Porous Media》2019,127(1):171-190

Transport in Porous Media - A methodology has been developed to create a pore network model (PNM) from the geometrical/topological information extracted from the micro-tomographic images of a...  相似文献   

    

Roozbeh Farhoudi  Mohammad Amin Mehrnia  Dong-Jin Lee 《Natural product research》2019,33(6):871-874

The present study was designed to evaluate the contents of different antioxidants compounds and their antioxidant activities in Jalopeno peppers (Capsicum annuum) cultivars (El Dorido, Grande, Tula, Sayula and El Rey) extracts. Free radical scavenging activity of Grande was recorded as high as 87% followed by El Dorido (83%). Results of reducing power (Fe³⁺ to Fe²⁺) showed that Grande (0.85%) and El Dorido (0.81%) fruit extract absorbance value were close to synthetic antioxidant BHT (0. 97%) obtained at100 μg/mL. The results showed that total phenolic content of El Dorido and Grande were significantly higher compared to other Jalapeno pepper. Results indicated strong and positive correlation between antioxidant activity and carotenoids content (r = 0.75), vitamin C (r = 0.78) and total capsaicinoids (r = 0.84), respectively. The results of the antioxidant activity assays showed that the El Dorido and Grande had strongest antioxidant activity compared to other peppers cultivars in this study.  相似文献   

    

Shiva Farzin  Abdollah Rahimi  Kamran Amiri  Abed Rostami  Amin Rostami 《应用有机金属化学》2018,32(9)

NiFe₂O₄ magnetic nanoparticles (MNPs) were synthesized, characterized and applied as an air‐stable, inexpensive and magnetically separable nanocatalyst for the synthesis of structurally diverse sulfides. Efficient methodologies were developed for the synthesis of unsymmetric diaryl sulfides via odourless and one‐pot reactions of triphenyltin chloride/S₈ or arylboronic acid/S₈ as thiolating agents with aryl halides or nitroarenes as starting materials in the presence of base (K₂CO₃ or NaOH) and NiFe₂O₄ MNPs as a catalyst in water or poly (ethylene glycol) as solvent at 80–110 °C. Free from ligand and the unpleasant smell of thiols and with the use of magnetically reusable nanocatalyst, green solvents and commercially available and cheap sulfur source and starting materials, these methods are more eco‐friendly and practical than available protocols for the synthesis of sulfides.  相似文献   

    

Seyyed Majid Jafarian Amiri  Mohsen Amiri 《代数通讯》2017,45(8):3396-3401

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Sk. Abdul Amin  Nilanjan Adhikari  Shovanlal Gayen  Tarun Jha 《Structural chemistry》2017,28(6):1663-1678

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Ali  Heba  Ismail  N.  Amin  M. S.  Mekewi  Mohamed 《Journal of Solid State Electrochemistry》2017,21(6):1605-1613

Journal of Solid State Electrochemistry - Efficient photoanodes are designed of vertically aligned anatase TiO2 nanotube arrays (anatase TNTAs) decorated with different shaped rutile TiO2...  相似文献