General strategies for nanoparticle dispersion     

Mackay ME  Tuteja A  Duxbury PM  Hawker CJ  Van Horn B  Guan Z  Chen G  Krishnan RS 《Science (New York, N.Y.)》2006,311(5768):1740-1743

Traditionally the dispersion of particles in polymeric materials has proven difficult and frequently results in phase separation and agglomeration. We show that thermodynamically stable dispersion of nanoparticles into a polymeric liquid is enhanced for systems where the radius of gyration of the linear polymer is greater than the radius of the nanoparticle. Dispersed nanoparticles swell the linear polymer chains, resulting in a polymer radius of gyration that grows with the nanoparticle volume fraction. It is proposed that this entropically unfavorable process is offset by an enthalpy gain due to an increase in molecular contacts at dispersed nanoparticle surfaces as compared with the surfaces of phase-separated nanoparticles. Even when the dispersed state is thermodynamically stable, it may be inaccessible unless the correct processing strategy is adopted, which is particularly important for the case of fullerene dispersion into linear polymers.  相似文献   

Thermodynamic Characterisation of Seed Deterioration during Storage under Accelerated Ageing Conditions     

P. Krishnan  Shantha Nagarajan  A.V. Moharir 《Biosystems Engineering》2004,89(4):425-433

  相似文献   

Influence of Two Extension Procedures on the Ubiquitous Microflora and the Biological Quality of Frozen Bovine Semen     

O Gérard  IJR Visser  HB Jansen 《Reproduction in domestic animals》1995,30(5):289-294

  相似文献   

Vitreous degeneration and associated ocular abnormalities in the dog     

Harathi Krishnan  Kathryn Diehl  Darko Stefanovski  Gustavo D. Aguirre 《Veterinary ophthalmology》2020,23(2):219-224

  相似文献   

Proteomic analysis of high protein soybean (Glycine max) accessions demonstrates the contribution of novel glycinin subunits     

Krishnan HB  Nelson RL 《Journal of agricultural and food chemistry》2011,59(6):2432-2439

Limited biochemical information is available on soybean accessions that have seed protein content greater than 45% of the seed dry weight. SDS-PAGE analysis of seed proteins from nine soybean accessions revealed significantly higher amount of seed storage proteins in these accessions when compared with that of soybean cultivar Williams 82. High-resolution two-dimensional gel electrophoretic analysis of seed proteins revealed significant differences among several seed storage protein components in these accessions. A total of 51 protein spots were identified using peptide mass fingerprinting (MALDI-TOF MS). The contribution of these proteins to the overall protein content of the accessions was quantified using Delta2D image analysis software. Results showed that among the majority of the nine accessions, the largest difference in higher protein quantity was within the seed 11S storage globulins. The high protein trait from PI407788A was successfully transferred to an experimental line, LG99-469, demonstrating that this trait was transferable and robust.  相似文献   

Colloidal nanocrystal shape and size control: the case of cobalt   总被引：1，自引：0，他引：1  

Puntes VF  Krishnan KM  Alivisatos AP 《Science (New York, N.Y.)》2001,291(5511):2115-2117

We show that a relatively simple approach for controlling the colloidal synthesis of anisotropic cadmium selenide semiconductor nanorods can be extended to the size-controlled preparation of magnetic cobalt nanorods as well as spherically shaped nanocrystals. This approach helps define a minimum feature set needed to separately control the sizes and shapes of nanocrystals. The resulting cobalt nanocrystals produce interesting two- and three-dimensional superstructures, including ribbons of nanorods.  相似文献   

Estimation of Coenzyme I Through the Uptake of Oxygen     

Krishnan PS 《Science (New York, N.Y.)》1947,105(2724):295

  相似文献   

PCR in a Rayleigh-Bénard convection cell     

Krishnan M  Ugaz VM  Burns MA 《Science (New York, N.Y.)》2002,298(5594):793

  相似文献   

An assessment of the genetic integrity of ex situ germplasm collections of three endangered species of Coffea from Madagascar: implications for the management of field germplasm collections     

Sarada Krishnan  Tom A. Ranker  Aaron P. Davis  Jean Jacques Rakotomalala 《Genetic Resources and Crop Evolution》2013,60(3):1021-1036

Madagascar has 59 species of Coffea, of which 42 are listed as Critically Endangered, Endangered, or Vulnerable by criteria of the Red List Category system of the World Conservation Union. In an attempt to assess the conservation value of ex situ collections of Malagasy coffee species, a study was undertaken using the field genebank collections maintained at the Kianjavato Coffee Research Station. Three species were selected for this purpose, C. kianjavatensis, C. montis-sacri, and C. vatovavyensis, and for comparative purposes extant, in situ populations of the same species were studied. Parentage analyses of ex situ propagated offspring of C. kianjavatensis and C. montis-sacri were performed to assess if crossing with other Coffea species maintained in the field genebank is compromising the genetic integrity of the collection. For these three species, higher genetic diversity was observed in the ex situ populations compared to the in situ populations, highlighting the importance of preserving the plants currently in ex situ collections. Parentage analyses of seed-propagated offspring of C. kianjavatensis and C. montis-sacri revealed that cross contamination with pollen from other Coffea species in the ex situ field genebank is occurring. These results have significant implications for the conservation management of wild Coffea species and for the management of ex situ genebanks.  相似文献   

The role of carbon dioxide during the onset of Antarctic glaciation     

Pagani M  Huber M  Liu Z  Bohaty SM  Henderiks J  Sijp W  Krishnan S  DeConto RM 《Science (New York, N.Y.)》2011,334(6060):1261-1264

Earth's modern climate, characterized by polar ice sheets and large equator-to-pole temperature gradients, is rooted in environmental changes that promoted Antarctic glaciation ~33.7 million years ago. Onset of Antarctic glaciation reflects a critical tipping point for Earth's climate and provides a framework for investigating the role of atmospheric carbon dioxide (CO(2)) during major climatic change. Previously published records of alkenone-based CO(2) from high- and low-latitude ocean localities suggested that CO(2) increased during glaciation, in contradiction to theory. Here, we further investigate alkenone records and demonstrate that Antarctic and subantarctic data overestimate atmospheric CO(2) levels, biasing long-term trends. Our results show that CO(2) declined before and during Antarctic glaciation and support a substantial CO(2) decrease as the primary agent forcing Antarctic glaciation, consistent with model-derived CO(2) thresholds.  相似文献