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排序方式: 共有159条查询结果,搜索用时 203 毫秒
151.
152.
Ion Pairing,H‐bonding,and π‐π Interactions in Cobalt(II) Compound Containing Guanidinium Counter Ion
Shabnam Sheshmani Hossein Aghabozorg Fahimeh Mohammad Panah Robabeh Alizadeh Guido Kickelbick Bahar Nakhjavan Abolghasem Moghimi Farshid Ramezanipour Hamid Reza Aghabozorg 《无机化学与普通化学杂志》2006,632(3):469-474
A novel proton transfer compound, (GH)2(phendc), ( 1 ), was synthesized from the reaction of 1,10‐phenanthroline‐2,9‐dicarboxylic acid, phendcH2, and guanidine hydrochloride, (GH)(Cl), (G: guanidine). The characterization was performed using IR, 1H and 13C NMR spectroscopy. The cobalt(II) compounds were synthesized using proton transfer compounds containing guanidinium counter ion. These proton transfer compounds are (GH)2(phendc), and (GH)2(pydc) (pydcH2: 2,6‐pyridinedicarboxylic acid). The chemical formulae and space groups are (GH)2[Co(phendc)2]·4H2O, (2) , and (GH)2[Co(H2O)6][Co(pydc)2]2, P21/n (3) . Non‐covalent interactions such as ionpairing, hydrogen bonding and π‐π stacking are discussed. 相似文献
153.
Preparation of perchloric acid supported on alumina and its primary application as a solid supported heterogeneous catalyst to the synthesis of α-(α-amidobenzyl)-β-naphthols by a one-pot, three-component condensation of benzaldehydes, β-naphthol and acetamide or benzamide under thermal solvent-free conditions were described. The present methodology offers several advantages such as simple procedure, shorter reaction time, and excellent yields. 相似文献
154.
Nahideh Gharehaghaji Mohammad Ali Oghabian Saeed Sarkar Fahimeh Darki 《Journal of magnetism and magnetic materials》2009,321(10):1563-1565
In this study, the volume of susceptibility artifact was evaluated in T1 and T2-weighted spin echo (SE) and gradient echo (GRE) images at various parameters using registration and subtraction methods. In order to state an important misinterpretation problem in lymphography, it was demonstrated that a lymph node size may be enlarged approximately 10 times when a T2*-weighted GRE protocol is used. To overcome this problem a technical consideration using multisequence (GRE and SE) paradigm was suggested to ensure both lymph node detection and metastasis identification in lymphatic system. The paradigm was also extended by post-processing manipulation of the SE images using a registration and subtraction approach for detection of lymphatic lesions. 相似文献
155.
Tahernejad-Javazmi Fahimeh Shabani-Nooshabadi Mehdi Karimi-Maleh Hassan Naeimi Hossein 《Research on Chemical Intermediates》2018,44(9):5389-5401
Research on Chemical Intermediates - Hydrazine and 4-chlorophenol are two major water pollutants, and determination of them is very important for human health. A new hydroquinone derivative, i.e.... 相似文献
156.
Fahimeh Baroughi Bonab Rainer E. Burkard Elisabeth Gassner 《Mathematical Methods of Operations Research》2011,73(2):263-280
The inverse p-median problem with variable edge lengths on graphs is to modify the edge lengths at minimum total cost with respect to given
modification bounds such that a prespecified set of p vertices becomes a p-median with respect to the new edge lengths. The problem is shown to be strongly NP{\mathcal{NP}}-hard on general graphs and weakly NP{\mathcal{NP}}-hard on series-parallel graphs. Therefore, the special case on a tree is considered: It is shown that the inverse 2-median
problem with variable edge lengths on trees is solvable in polynomial time. For the special case of a star graph we suggest
a linear time algorithm. 相似文献
157.
158.
Rastegari Arezoo Safavi Maliheh Vafadarnejad Fahimeh Najafi Zahra Hariri Roshanak Bukhari Syed Nasir Abbas Iraji Aida Edraki Najmeh Firuzi Omidreza Saeedi Mina Mahdavi Mohammad Akbarzadeh Tahmineh 《Molecular diversity》2022,26(1):409-428
Molecular Diversity - Alzheimer’s disease (AD) is now ranked as the third leading cause of death after heart disease and cancer. There is no definite cure for AD due to the multi-factorial... 相似文献
159.
Gholivand Khodayar Roshanian Zahra Rahimzadeh Dashtaki Maryam Hosseini Zahra Ebrahimi Valmoozi Ali Asghar Sharifi Mahboobeh Mohammadpanah Fahimeh Rajabi Maryam Ghadamyari Mohammad Farshadian Sedigheh Hasan Sajedi Reza Khajeh Khosro Akbari Neda 《Molecular diversity》2022,26(1):97-112
Molecular Diversity - Synthesizing new chemical compounds and studying their biological applications have been important issues in scientific research. In this investigation, we synthesized and... 相似文献