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Single crystal X-ray diffraction studies show that the extended structure of dipeptide Boc-beta-Ala-m-ABA-OMe (m-ABA: meta-aminobenzoic acid) self-assembles in the solid state by intermolecular hydrogen bonding to create an infinite parallel beta-sheet structure. In dipeptide Boc-gamma-Abu-m-ABA-OMe (gamma-Abu: gamma-aminobutyric acid), two such parallel beta-sheets are further cross-linked by intermolecular hydrogen bonding through m-aminobenzoic acid moieties. SEM (scanning electron microscopy) studies reveal that both the peptides and form amyloid-like fibrils in the solid state. The fibrils are also found to be stained readily by Congo red, a characteristic feature of the amyloid fiber whose accumulation causes several fatal diseases such as Alzheimer's, prion-protein etc. 相似文献
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A laser-induced forward transfer technique has been applied for the maskless patterning of amorphous V2O5 thin films. A sheet beam of a frequency doubled (SHG) Q-switched Nd:YAG laser was irradiated on a transparent glass substrate (donor), the rear surface of which was pre-coated with a vacuum-deposited V2O5 180 nm thick film was either in direct contact with a second glass substrate (receiver) or a 0.14 mm air-gap was maintained between the donor film and the receiving substrate. Clear, regular stripe pattern of the laser-induced transferred film was obtained on the receiver. The pattern was characterized using X-ray diffraction (XRD), optical absorption spectroscopy, scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), atomic force microscopy (AFM), etc. 相似文献
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Douglas N. Hales V. Sridharan Abirami Radhakrishnan Satya S. Chakravorty Samia M. Siha 《European Journal of Operational Research》2008
Although Information Technology (IT) solutions improve the collection and validation of operational data, Operations Managers must often rely on self-reported data from workers to make decisions. The problem with this data is that they are subject to intentional manipulation, thus reducing their suitability for decision-making. A method of identifying manipulated data, digital analysis, addresses this problem at low cost. In this paper, we demonstrate how one uses this method in real-world companies to validate self-reported data from line workers. The results of our study suggest that digital analysis estimates the accuracy of employee reported data in operations management, within limited contexts. These findings lead to improved operating performance by providing a tool for practitioners to exclude inaccurate information. 相似文献
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Krishna C. Majumdar Buddhadeb Chattopadhyay Santanu Chakravorty Nilasish Pal Randhir Kumar Sinha 《Tetrahedron letters》2008,49(50):7149-7152
The synthesis and characterization of a homologous series of Schiff bases consisting of an N-methyldiphenylamine moiety as the central core is reported, which exhibits smectic A phase and transitions from the partial bilayer SmAd phase to the bilayer SmA2 phase as the temperature is lowered. 相似文献
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Chakravorty H. van Mourik J. Coolen A.C.C. 《The European physical journal. E, Soft matter》2001,5(1):539-550
The European Physical Journal E - In this paper we analyse both the dynamics and the high density physics of the infinite dimensional lattice gas model for random heteropolymers recently introduced... 相似文献
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Animesh Roy Maximilian A. Silvestri Robert A. Hall Salvatore D. Lepore 《Tetrahedron letters》2017,58(1):106-108
In the attempt to synthesize substituted allenyl esters through a metathesis coupling of unsubstituted allenyl esters and alkenes using a variety of ruthenium catalysts, it was discovered that allenyl esters themselves cleanly arrested the activity of the catalysts. Further studies suggests possible utility of allene esters as general quenching agents for metathesis reactions. To explore this idea, several representative olefin metathesis reactions, including ring closing, were successfully terminated by the addition of simple allenyl esters for more convenient purification. 相似文献
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It is a well-known fact that the degree distribution (DD) of the nodes in a partition of a bipartite network influences the DD of its one-mode projection on that partition. However, there are no studies exploring the effect of the DD of the other partition on the one-mode projection. In this article, we show that the DD of the other partition, in fact, has a very strong influence on the DD of the one-mode projection. We establish this fact by deriving the exact or approximate closed-forms of the DD of the one-mode projection through the application of generating function formalism followed by the method of iterative convolution. The results are cross-validated through appropriate simulations. 相似文献
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