‘Pictorial relief’ is a surface in 3D ‘pictorial space’. It is perceived in single flat pictures and clearly has nothing to do with binocular stereopsis but with the interpretation of image structure in terms of relations in the external world. Ways to perform geometrical measurements in pictorial space are presented and a number of empirical results are reviewed. Applications to the theory of optical instruments aiding human vision are discussed.
{"title":"Pictorial relief","authors":"J. Koenderink","doi":"10.1098/rsta.1998.0211","DOIUrl":"https://doi.org/10.1098/rsta.1998.0211","url":null,"abstract":"‘Pictorial relief’ is a surface in 3D ‘pictorial space’. It is perceived in single flat pictures and clearly has nothing to do with binocular stereopsis but with the interpretation of image structure in terms of relations in the external world. Ways to perform geometrical measurements in pictorial space are presented and a number of empirical results are reviewed. Applications to the theory of optical instruments aiding human vision are discussed.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79509090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An electrode is an ideal catalyst in that the potential difference at the electrodesolution interface controls both the thermodynamics and the kinetics of the electrochemical reactions. However, the kinetics of electrode processes are relatively unselective. Greater selectivity can be achieved by the use of modified electrodes in which a redox catalyst is attached to the electrode surface. The kinetics of charge transfer in the modified layer are discussed in this paper. Another major problem is that the reactant must find the electrode. High conversions can be achieved by using a packed bed electrode. Results are presented showing how the performance of this type of electrode can be improved by using a graded bed rather than a uniform bed.
{"title":"Electrode kinetics","authors":"W. Albery","doi":"10.1098/rsta.1981.0162","DOIUrl":"https://doi.org/10.1098/rsta.1981.0162","url":null,"abstract":"An electrode is an ideal catalyst in that the potential difference at the electrodesolution interface controls both the thermodynamics and the kinetics of the electrochemical reactions. However, the kinetics of electrode processes are relatively unselective. Greater selectivity can be achieved by the use of modified electrodes in which a redox catalyst is attached to the electrode surface. The kinetics of charge transfer in the modified layer are discussed in this paper. Another major problem is that the reactant must find the electrode. High conversions can be achieved by using a packed bed electrode. Results are presented showing how the performance of this type of electrode can be improved by using a graded bed rather than a uniform bed.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1098/rsta.1981.0162","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72420822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Correction for ‘Recent studies of internal and surface nucleation in silicate glasses’ by E. D. Zanotto and V. M. Fokin (Phil. Trans. R. Soc. Lond. A 361, 2633–2647. (doi: 10.1098/rsta.2003.1261)). The first sentence of the abstract should read as follows: ‘Find the next term in the sequence 1, 1, 12, 620, 87 304.’
E. D. Zanotto和V. M. Fokin (Phil.)对“硅酸盐玻璃内部和表面成核的最新研究”的更正。反式。r . Soc。Lond。A 361, 2633-2647。(doi: 10.1098 / rsta.2003.1261))。摘要的第一句话应该是这样写的:“找出序列1、1、12、620、87、304中的下一项。”
{"title":"Correction for Strachan, How to count curves: from nineteenth-century problems to twenty-first-century solutions","authors":"I. Strachan","doi":"10.1098/RSTA.2004.2000","DOIUrl":"https://doi.org/10.1098/RSTA.2004.2000","url":null,"abstract":"Correction for ‘Recent studies of internal and surface nucleation in silicate glasses’ by E. D. Zanotto and V. M. Fokin (Phil. Trans. R. Soc. Lond. A 361, 2633–2647. (doi: 10.1098/rsta.2003.1261)). The first sentence of the abstract should read as follows: ‘Find the next term in the sequence 1, 1, 12, 620, 87 304.’","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82970315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Correction for ‘Near-field photonic forces’ by M. Nieto-Vesperinas, P. C. Chaumet and A. Rahmani (Phil. Trans. R. Soc. Lond. A 362, 719–737. (doi: 10.1098/rsta.2003.1343)). Figures 3 and 4 are reproduced in their correct form here.
{"title":"Correction for Nieto-Vesperinas et al., Near-field photonic forces","authors":"M. Nieto-Vesperinas, P. Chaumet, A. Rahmani","doi":"10.1098/RSTA.2004.2001","DOIUrl":"https://doi.org/10.1098/RSTA.2004.2001","url":null,"abstract":"Correction for ‘Near-field photonic forces’ by M. Nieto-Vesperinas, P. C. Chaumet and A. Rahmani (Phil. Trans. R. Soc. Lond. A 362, 719–737. (doi: 10.1098/rsta.2003.1343)). Figures 3 and 4 are reproduced in their correct form here.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73133575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Correction for ‘Recent studies of internal and surface nucleation in silicate glasses’ by E. D. Zanotto and V. M. Fokin (Phil. Trans. R. Soc. Lond. A 361, 591–613. (doi: 10.1098/rsta.2002.1150)). The following is the correct form of the first sentence of §3a.
E. D. Zanotto和V. M. Fokin (Phil.)对“硅酸盐玻璃内部和表面成核的最新研究”的更正。反式。r . Soc。Lond。361, 591-613。(doi: 10.1098 / rsta.2002.1150))。下面是§3a第一句的正确形式。
{"title":"Correction for Zanotto and Fokin, Recent studies of internal and surface nucleation in silicate glasses","authors":"Edgar Dutra Zanotto, V. Fokin","doi":"10.1098/RSTA.2003.2000","DOIUrl":"https://doi.org/10.1098/RSTA.2003.2000","url":null,"abstract":"Correction for ‘Recent studies of internal and surface nucleation in silicate glasses’ by E. D. Zanotto and V. M. Fokin (Phil. Trans. R. Soc. Lond. A 361, 591–613. (doi: 10.1098/rsta.2002.1150)). The following is the correct form of the first sentence of §3a.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87733357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Keller, R. Tharmann, M. Dichtl, A. Bausch, E. Sackmann
This paper deals with correlations between the viscoelastic impedance of entangled actin networks and the slow conformational dynamics and diffusive motions of single filaments. The single filament dynamics is visualized and analysed by analysing the Brownian motion of attached colloidal beads, which enables independent measurements of characteristic viscoelastic response times such as the entanglement and reptation times. We further studied the frequency–dependent viscoelastic impedance of active actin–heavy–meromyosin II networks by magnetic–tweezers microrheometry to gain insight into the effect of such highly dynamic and force–generating crosslinkers (exhibiting bond lifetimes of less than 1 s) on the rheological properties. We show that at high frequencies (higher than 1 Hz) the viscoelastic loss modulus is slightly increased relative to the entangled network (associated with an increase in the energy dissipated during mechanical excitations), while at low frequencies the plateau of the impedance spectrum becomes more pronounced as a consequence of the cross–linking of the network and the suppression of the terminal regime. Our data provide evidence that the myosin motor protein may play a role as softener of the actin cortex, enabling the adaptive reduction of the yield stress of cells and thus facilitating cellular deformations.
{"title":"Slow filament dynamics and viscoelasticity in entangled and active actin networks","authors":"M. Keller, R. Tharmann, M. Dichtl, A. Bausch, E. Sackmann","doi":"10.1098/rsta.2002.1158","DOIUrl":"https://doi.org/10.1098/rsta.2002.1158","url":null,"abstract":"This paper deals with correlations between the viscoelastic impedance of entangled actin networks and the slow conformational dynamics and diffusive motions of single filaments. The single filament dynamics is visualized and analysed by analysing the Brownian motion of attached colloidal beads, which enables independent measurements of characteristic viscoelastic response times such as the entanglement and reptation times. We further studied the frequency–dependent viscoelastic impedance of active actin–heavy–meromyosin II networks by magnetic–tweezers microrheometry to gain insight into the effect of such highly dynamic and force–generating crosslinkers (exhibiting bond lifetimes of less than 1 s) on the rheological properties. We show that at high frequencies (higher than 1 Hz) the viscoelastic loss modulus is slightly increased relative to the entangled network (associated with an increase in the energy dissipated during mechanical excitations), while at low frequencies the plateau of the impedance spectrum becomes more pronounced as a consequence of the cross–linking of the network and the suppression of the terminal regime. Our data provide evidence that the myosin motor protein may play a role as softener of the actin cortex, enabling the adaptive reduction of the yield stress of cells and thus facilitating cellular deformations.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89049627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Herlach, D. Holland-Moritz, R. Willnecker, D. Herlach, K. Maier
Long–range magnetic order in metals and alloys is restricted to the solid state of matter, since the Curie temperatures of all known metallic materials are below their respective melting temperatures. This article reviews recent investigations on the maximum undercoolability of Co–based alloys, which show high relative Curie temperatures. Experiments on drops undercooled containerlessly by electromagnetic levitation show the onset of magnetic ordering when the temperature is approaching the Curie temperature. Studies of the nucleation behaviour propose a magnetic contribution to the activation energy to form crystal nuclei of critical size in deeply undercooled Co–rich melts.
{"title":"Magnetic ordering and crystal nucleation in undercooled Co–based melts","authors":"D. Herlach, D. Holland-Moritz, R. Willnecker, D. Herlach, K. Maier","doi":"10.1098/rsta.2002.1140","DOIUrl":"https://doi.org/10.1098/rsta.2002.1140","url":null,"abstract":"Long–range magnetic order in metals and alloys is restricted to the solid state of matter, since the Curie temperatures of all known metallic materials are below their respective melting temperatures. This article reviews recent investigations on the maximum undercoolability of Co–based alloys, which show high relative Curie temperatures. Experiments on drops undercooled containerlessly by electromagnetic levitation show the onset of magnetic ordering when the temperature is approaching the Curie temperature. Studies of the nucleation behaviour propose a magnetic contribution to the activation energy to form crystal nuclei of critical size in deeply undercooled Co–rich melts.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81305312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent progress in understanding the inoculation of aluminium melts is reviewed. Transmission electron microscopy of inoculant particles in a metallic glass reveals details of the mechanism of nucleation of aluminium grains. While such studies define some of the conditions under which inoculation is effective or not, they do not permit a prediction of grain size. Unusually for a nucleation–related phenomenon, quantitative prediction is possible. For potent inoculation such as is practised in aluminium alloys, grain initiation is limited by inoculant particle size, occurring first on the largest particles. Simple thermal models can then describe the dependence of grain refinement on alloy content and processing conditions, and enable consideration of inoculant design.
{"title":"Grain refinement of alloys by inoculation of melts","authors":"By A. L. Greer","doi":"10.1098/rsta.2002.1147","DOIUrl":"https://doi.org/10.1098/rsta.2002.1147","url":null,"abstract":"Recent progress in understanding the inoculation of aluminium melts is reviewed. Transmission electron microscopy of inoculant particles in a metallic glass reveals details of the mechanism of nucleation of aluminium grains. While such studies define some of the conditions under which inoculation is effective or not, they do not permit a prediction of grain size. Unusually for a nucleation–related phenomenon, quantitative prediction is possible. For potent inoculation such as is practised in aluminium alloys, grain initiation is limited by inoculant particle size, occurring first on the largest particles. Simple thermal models can then describe the dependence of grain refinement on alloy content and processing conditions, and enable consideration of inoculant design.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83365269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The classical theory of homogeneous nucleation is an interface–limited theory and does not strictly apply for transformations where long–range diffusion is dominant. A new approach that takes account of the coupled stochastic fluxes of interface attachment and long–range diffusion is presented. Steady–state nucleation rates can be orders of magnitude smaller and the induction times for time–dependent nucleation correspondingly larger than expected from the classical theory. In solute precipitation, the regions of the parent phase near subcritical precipitate clusters are enriched (rather than depleted) in solute. Oxygen precipitation in silicon is chosen to illustrate these features. Measured precipitate densities following multi–step anneals show better agreement with predictions from the coupled–flux model than with those from the classical theory. The kinetics of formation for small oxide clusters and the dependence of their population density on the initial oxygen concentration agree well with data for thermal donor defects.
{"title":"Diffusion–influenced nucleation: a case study of oxygen precipitation in silicon","authors":"K. Kelton","doi":"10.1098/rsta.2002.1138","DOIUrl":"https://doi.org/10.1098/rsta.2002.1138","url":null,"abstract":"The classical theory of homogeneous nucleation is an interface–limited theory and does not strictly apply for transformations where long–range diffusion is dominant. A new approach that takes account of the coupled stochastic fluxes of interface attachment and long–range diffusion is presented. Steady–state nucleation rates can be orders of magnitude smaller and the induction times for time–dependent nucleation correspondingly larger than expected from the classical theory. In solute precipitation, the regions of the parent phase near subcritical precipitate clusters are enriched (rather than depleted) in solute. Oxygen precipitation in silicon is chosen to illustrate these features. Measured precipitate densities following multi–step anneals show better agreement with predictions from the coupled–flux model than with those from the classical theory. The kinetics of formation for small oxide clusters and the dependence of their population density on the initial oxygen concentration agree well with data for thermal donor defects.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85756927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article reviews recent findings on internal and surface nucleation in silicate glasses. The internal homogeneous nucleation rates sharply decrease and the induction times increase with the Tg/TL ratio (Tg is the glass–transition temperature and TL is the liquidus temperature). Only systems that have Tg/TL < 0.58 display measurable internal nucleation rates on a laboratory time–scale. Numerous tests of the classical nucleation theory have demonstrated that the theory fails to describe nucleation rates in glasses quantitatively. Possible explanations for this failure are tested and discussed. Surface nucleation depends strongly on the surface quality, e.g. tips, cracks and scratches, elastic stresses, foreign particles and surrounding atmosphere. The mechanisms of surface nucleation are still not fully understood, but some of the key factors are now known and the surface–nucleation density can thus be controlled for the development of sintered glasses or glass ceramics.
{"title":"Recent studies of internal and surface nucleation in silicate glasses","authors":"Edgar Dutra Zanotto, V. Fokin","doi":"10.1098/rsta.2002.1150","DOIUrl":"https://doi.org/10.1098/rsta.2002.1150","url":null,"abstract":"This article reviews recent findings on internal and surface nucleation in silicate glasses. The internal homogeneous nucleation rates sharply decrease and the induction times increase with the Tg/TL ratio (Tg is the glass–transition temperature and TL is the liquidus temperature). Only systems that have Tg/TL < 0.58 display measurable internal nucleation rates on a laboratory time–scale. Numerous tests of the classical nucleation theory have demonstrated that the theory fails to describe nucleation rates in glasses quantitatively. Possible explanations for this failure are tested and discussed. Surface nucleation depends strongly on the surface quality, e.g. tips, cracks and scratches, elastic stresses, foreign particles and surrounding atmosphere. The mechanisms of surface nucleation are still not fully understood, but some of the key factors are now known and the surface–nucleation density can thus be controlled for the development of sintered glasses or glass ceramics.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80570761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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