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Inside Cover: Seeding Molecular Rotators on a Passivated Silicon Surface (ChemPhysChem 2/2014) 下载免费PDF全文
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Dr. Oliver Guillermet Dr. Ather Mahmood Dr. Jianshu Yang Dr. Jorge Echeverria Judicael Jeannoutot Dr. Sebastien Gauthier Dr. Christian Joachim Dr. Frederic Chérioux Prof. Dr. Frank Palmino 《Chemphyschem》2014,15(2):271-275
Thermally activated rotation of single molecules adsorbed on a silicon‐based surface between 77 and 150 K has been successfully achieved. This remarkable phenomenon relies on a nanoporous supramolecular network, which acts as a template to seed periodic molecule rotors on the surface. Thermal activation of rotation has been demonstrated by STM experiments and confirmed by theoretical calculations. 相似文献
3.
Ather Farooq Khan Muhammad Awais Abdul Samad Khan Sobia Tabassum Aqif Anwar Chaudhry Ihtesham Ur Rehman 《应用光谱学评论》2013,48(4):329-355
Abstract Raman spectroscopy of natural bones and hydroxyapatites is described. In addition, how Raman spectroscopy has proved crucial in providing baseline data for the modification of synthetic apatite powders that are routinely used now as bone replacement materials is explained. It is important to understand the chemical structural properties of natural bone. Bone consists of two primary components: an inorganic or mineral phase, which is mainly a carbonated form of a nanoscale crystalline calcium phosphate, closely resembling hydroxyapatite, and an organic phase, which is composed largely of type I collagen fibers. Other constituents of bone tissue include water and organic molecules such as glycosaminoglycans, glycoproteins, lipids, and peptides. Ions such as sodium, magnesium, fluoride, and citrate are also present, as well as hydrogenophosphate. Hence, the mineral phase in bone may be characterized essentially as nonstoichiometric substituted apatite. Such a distinction is important in the development of synthetic calcium phosphates for application as skeletal implants. An understanding of bone function and its interfacial relationship to an implant clearly depends on the associated structure and composition. Therefore, it is essential to fully understand the chemical composition of bone, and Raman spectroscopy is an excellent technique for such an analysis. 相似文献
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Farooq U Khan A Khan AF Khan SS Sarwar R Ahmad VU Waseem A 《Natural product communications》2012,7(2):149-150
Two new ballonigrin type lactone diterpenoids, named ballonigrin lactone A and B, have been isolated from the roots of Ballota limbata. Structure elucidation of the isolated compounds was based on spectroscopic {IR, 1H- and 3C-NMR, and 2D-NMR (HMQC, HMBC, COSY and NOESY} and EI-MS data. 相似文献
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Minjoong Yoon Roger M. Leblanc M. Ather Ali Peter H. Heinermann 《Photochemistry and photobiology》1988,48(4):549-552
Abstract— The photoacoustic spectra of porphyropsin in the creek chub (Semotilus atromaculatus) have been successfully measured on single retinae of small size (< 0.5 cm in diameter) at low temperatures. The relative intensities of the spectra, corresponding to the thermal release, are strong enough to be comparable to those for the big cattle retina. The photoacoustic spectrum of porphyropsin at – 167° C exhibits a principal maximum at 540 nm with a small shoulder near 580 nm. A sequence of porphyropsin bleaching resulted from thermal reaction has been clearly observed above -90° C. 相似文献
6.
Rubina Munir Noman Javid Muhammad Zia-ur-Rehman Muhammad Zaheer Rahila Huma Ayesha Roohi Muhammad Makshoof Athar 《Molecules (Basel, Switzerland)》2021,26(16)
In this article, a synthesis of N’-(benzylidene)-2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetohydrazides and their structural interpretation by NMR experiments is described in an attempt to explain the duplication of some peaks in their 1H- and 13C-NMR spectra. Twenty new 6-methyl-1H-pyrazolo[3,4-b]quinoline substituted N-acylhydrazones 6(a–t) were synthesized from 2-chloro-6-methylquinoline-3-carbaldehyde (1) in four steps. 2-Chloro-6-methylquinoline-3-carbaldehyde (1) afforded 6-methyl-1H-pyrazolo[3,4-b]quinoline (2), which upon N-alkylation yielded 2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetate (3). The hydrazinolysis of 3 followed by the condensation of resulting 2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetohydrazide (4) with aromatic aldehydes gave N-acylhydrazones 6(a–t). Structures of the synthesized compounds were established by readily available techniques such as FT-IR, NMR and mass spectral studies. The stereochemical behavior of 6(a–t) was studied in dimethyl sulfoxide-d6 solvent by means of 1H NMR and 13C NMR techniques at room temperature. NMR spectra revealed the presence of N’-(benzylidene)-2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetohydrazides as a mixture of two conformers, i.e., E(C=N)(N-N) synperiplanar and E(C=N)(N-N) antiperiplanar at room temperature in DMSO-d6. The ratio of both conformers was also calculated and E(C=N) (N-N) syn-periplanar conformer was established to be in higher percentage in equilibrium with the E(C=N) (N-N) anti-periplanar form. 相似文献
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Integration with weight functions is used in countless mathematical problems such as: approximation theory and spectral analysis, statistical analysis and the theory of distributions. The aim of this paper is to establish a new inequality using weight function which generalizes the inequalities of Barnett et al. in 2001 and Rafiq et al. in 2006. We also discuss some other interesting inequalities in special cases. Perturbed midpoint and trapezoid inequalities are also obtained. Some applications in numerical integration are also given. 相似文献
8.
Synthesis of 1‐(p‐Sulphophenyl)‐3‐methyl‐5‐pyrazolone Based Acid Dyes and Their Applications on Leather 下载免费PDF全文
Ghulam Hussain Nasir Abbas Makshoof Ather Misbah Ul Ain Khan Aamer Saeed Rashid Saleem Ghulam Shabir 《中国化学会会志》2016,63(8):645-652
A new series of pyrazolone based azo acid dyes (3a–g) has been synthesized starting from 1‐(p‐sul‐phophenyl)‐3‐methyl‐5‐pyrazolone (1). The synthetic methodology included the nitrosation of p‐sulphophenyl methyl pyrazolone followed by reduction, diazotization and coupling with Naphthol AS derivatives (2a–f), in alkaline medium to yield different acid dyes. Multichromic metal complexes of these dyes (5a–f, 6a–f and 7a–f) with 3d transition metals Chromium, Iron and Copper were also synthesized. The structures of all of newly synthesized compounds were confirmed by analytical data and spectroscopic techniques. The synthesized dyes were applied on leather to assess their light fastness, wash fastness and rubbing fastness and were shown to exhibit high values of 4–5 for majority of dyes. 相似文献
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Munawar A. Munawar Muhammad Azad Makshoof Athar Paul W. Groundwater 《Chemical Papers》2008,62(3):288-293
A series of 2-pyrazolines was prepared in a reaction of quinolinylchalcones with phenyl hydrazine under both conventional
and microwave-induced heating. Structures of the synthesized compounds were characterized by spectroscopic data and CHN analyses.
All prepared compounds were tested for antimicrobial activity against bacterial strains, viz. Staphylococcus aureus, Salmonella typhii, Escherichia coli, and Shigella dysentery. Almost all synthesized compounds have shown antimicrobial activity; however, compounds with a chloro group as a substituent
have been found to be more effective. 相似文献