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1.
Dr. Raysa Khan Tareque Dr. Storm Hassell-Hart Dr. Tobias Krojer Dr. Anthony Bradley Dr. Srikannathasan Velupillai Dr. Romain Talon Dr. Michael Fairhead Dr. Iain J. Day Kamlesh Bala Dr. Robert Felix Dr. Paul D. Kemmitt Prof. Paul Brennan Prof. Frank von Delft Dr. Laura Díaz Sáez Prof. Kilian Huber Prof. John Spencer 《ChemMedChem》2020,15(24):2513-2520
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified. 相似文献
2.
Vedantham Ramachandran Reddy Edara Sreenivasa 《Multimedia Tools and Applications》2020,79(29-30):21487-21512
Multimedia Tools and Applications - Facial expression is the most common technique is used to convey the expressions of human beings. Due to different ethnicity and age, faces differ from one... 相似文献
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4.
Hwar-Ching Ku Bala Ramaswamy 《International journal for numerical methods in engineering》1995,38(4):667-683
A new multi-grid (two-grid) pseudospectral element method has been carried out for solution of incompressible flow in terms of primitive variable formulation. The main objective of the proposed method is to apply the multi-grid technique solving the incompressible flow problems associated with three commonly encountered multi-grid environments. In domain decomposition terminology, it includes (I) partially overlapped subdomains, each of which has same types of grids; (II) partially overlapped subdomains, each of which has different types of grids; (III) local adaptive subdomains fully overlapped with the original computational domain (composite grids). The approach for flow problems, complex geometry or not, is to first divide the computational domain into a number of subdomains with the inter-overlapping area (partially or fully overlapped). In categories I and II, the fine-grid or coarse-grid subdomains can be defined by their representation, while in category III the fine-grid or coarse-grid subdomains are defined as usual. Next, implement the Schwarz Alternating Procedure (SAP) to exchange the data among subdomains, where the coarse-grid correction is used to remove the high frequency error that occurs when the data interpolation from the fine-grid subdomain to the coarse-grid subdomain is conducted. The strategy behind the coarse-grid correction is to adopt the operator of the divergence of velocity field, which intrinsically links the pressure equation, into this process. The solution of each subdomain can be efficiently solved by the direct (or iterative) eigenfunction expansion technique or preconditioned method with the least storage requirement, i.e. O(N2) in 2-D. Numerical results of (i) driven cavity flow (Re = 100,400) with Cartesian grids (category I) in each subdomain, (ii) driven cavity flow (Re = 3200) with local adaptive grids (category III) in each subdomain, and (iii) flow over a cylinder (Re = 250) with ‘O’ grids in one subdomain and Cartesian grids in another (category II) will be presented in the paper to account for the versatility of the proposed multi-grid method. 相似文献
5.
P. Bala Srinivasan C. V. Krishnakumar N. Krishnaraj 《Journal of Materials Engineering and Performance》2002,11(5):509-515
Salt bath nitrocarburizing is a well-known thermochemical diffusion process for enhancing the tribological and corrosion properties
of ferrous components. The current work describes the role of a compound layer developed during nitrocarburizing, both in
the ferritic and austenitic regimes of Fe-N-C system, on the sliding wear behavior of a medium carbon steel. The wear behavior
of the nitrocarburized steel discs was assessed by the pin-on-disc tests (ASTM G 99-99) under different normal loads running
against a hardened SAE52100 pin. It was observed that the compound layer on the surface not only controlled the wear rate
but also resisted the adhesive wear/transfer of material from pin to disc, aside from providing low-friction coefficients. 相似文献
6.
Long-period fibre gratings in specially designed birefringent few-mode fibres are used to demonstrate spectrally flat polarisers with bandwidths of 10 nm and polarisation extinction levels of 20 dB. This is enabled by the special dispersive properties of few-mode fibres, yielding fibre polarisers with performance approaching that of bulk-optic devices. 相似文献
7.
Lakshmi Ramachandran Nanjangud C. Narendra Karthikeyan Ponnalagu 《Service Oriented Computing and Applications》2012,6(4):283-302
Cloud-based systems promise an on-demand service provisioning system along with a ??pay-as-you-use?? policy. In the case of multi-tenant systems this would mean dynamic creation of a tenant by integrating existing cloud-based services on the fly. Presently, dynamic creation of a tenant is handled by building the required components from scratch. Although multi-tenant systems help providers save cost by allocating multiple tenants to the same instance of an application, they incur huge reconfiguration costs. Cost and time spent on these reconfiguration activities can be reduced by re-constructing tenants from existing tenant configurations supported by service providers. Multi-tenant cloud-based systems also lack the facility of allowing clients to specify their requirements. Giving clients the flexibility to specify requirements helps them avoid spending an excessive amount of time and effort looking through a list of services, many of which might not be relevant to them. Moreover, dynamic provisioning in the cloud requires an integrated solution across the technology stack (software, platform and infrastructure) combining functional, non-functional and resource allocation requirements. Existing research works in the area of web service matching, although numerous, still fall short, since they usually consider each requirement type in isolation and cannot provide an integrated solution. To that end, in this paper we investigate the features needed for dynamic service provisioning on the cloud. We propose a novel User Interface-Tenant Selector-Customizer (UTC) model and approach, which enables cloud-based services to be systematically modeled and provisioned as variants of existing service tenants in the cloud. Our approach considers functional, non-functional and resource allocation requirements, which are explicitly specified by the client via the user interface component of the model. To the best of our knowledge, ours is the first such integrated approach. We illustrate our ideas using a realistic running example, and also present a proof-of-concept prototype built using IBM??s Rational Software Architect modeling tool. We also present experimental results demonstrating the applicability of our matching algorithm. Our results show significant reduction in matching time with the help of an elimination process that reduces the search space needed for performing matching. 相似文献
8.
V. S. Ramachandran 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1972,22(11):1125-1138
The hydration characteristics of 3CaO.SiO2 or β2CaO.SiO2 are studied by an addition of 0.0, 0.1, 0.5 or 1.0% triethanolamine. The amount of Ca(OH)2 found at 1, 3, 7 or 28 days was in the order C3S + 0% TEA > C3S +0.1% TEA > C3S + 0.5% TEA > C3S+1.0% TEA, irrespective of whether lime was estimated by X-ray, DTA, TGA or chemical analysis. The rate of hydration, in terms of the disappearance of 3CaO.SiO2, showed that hydration proceeded faster in the presence of TEA after 1 day. Additions of TEA increase the induction period, promote the formation of a C-S-H with higher CaO/SiO2 ratio, increase the formation of non-crystalline Ca(OH)2 and enhance the surface area of the hydrated silicate product. 相似文献
9.
Mass transfer across gas and liquid boundary layers into the core of drops with liquid phase first order chemical reaction has been analyzed for spherical drops in the Reynolds number range of 50 < Reg < 400. The realistic and computationally efficient simulation of this gas absorption system is applicable in a variety of engineering fields including gas-liquid mass transfer in drops and sprays. The present paper deals with the fluid mechanics and mass transfer with chemical reaction of a single drop. In computer experiments good predictive agreement has been achieved with measured data. The theoretical results were generalized to show the influence of three major system parameters: Peclet number Peg or Pel Damköhler number Da and the distribution coefficient at the gas-liquid interface, M, on mass transfer and to demonstrate the importance of coupled gas- and liquid-phase resistances to gas absorption under practical conditions. 相似文献
10.
Temperature programmed desorption (TPD) and reduction (TPR) studies were carried out on H2S and thiophene adsorbed on Mo/Al2O3 and CoMo/Al2O3 catalysts. Freshly sulfided and pyridine poisoned catalysts were run. For sulfided catalysts, the major products of desorption of thiophene were thiophene and butene, leaving a carbonaceous residue. Subsequent TPR in H2 effected complete removal of the residue with formation of H2S, thiophene and butene. The residue appeared to consist of an easily reactive thiophene polymer and a less-reactive, sulfur-containing coke. Runs on poisoned catalysts showed less adsorption but product profiles were similar, showing that the adsorption characteristics of the remaining sites were not significantly altered. 相似文献