A method of partitioning the energy in a mixed population of active and photoinactivated Photosystem II (PS II) complexes based on chlorophyll fluorescence measurements is presented. There are four energy fluxes, each with its quantum efficiency: a flux associated with photochemical electron flow in active PS II reaction centres (JPS II), thermal dissipation in photoinactivated, non-functional PS IIs (JNF), light-regulated thermal dissipation in active PS IIs (JNPQ) and a combined flux of fluorescence and constitutive, light-independent thermal dissipation (Jf,D). The four quantum efficiencies add up to 1.0, without the need to introduce an 'excess' term E, which in other studies has been claimed to be linearly correlated with the rate coefficient of photoinactivation of PS II (kpi). We examined the correlation of kpi with various fluxes, and found that the combined flux (JNPQ + Jf,D= Jpi) is as well correlated with kpi as is E. This combined flux arises from Fs/Fm ', the ratio of steady-state to maximum fluorescence during illumination, which represents the quantum efficiency of combined non-photochemical dissipation pathways in active PS IIs. Since Fs/Fm ' or its equivalent, Jpi, is a likely source of events leading to photoinactivation of PS II, we conclude that Fs/Fm ' is a simple predictor of kpi.
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http://dx.doi.org/10.1007/s11120-004-6430-4 | DOI Listing |
Langmuir
January 2025
Guangdong Provincial Key Laboratory of Thermal Management Engineering & Materials, National-Local Joint Engineering Laboratory of Functional Carbon Materials, Shenzhen 518055, China.
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View Article and Find Full Text PDFNanotechnology
January 2025
Electronic Sci.&Eng., Xi'an Jiaotong University, 28 Xianning West Road,Beilin District, Xi 'an, Shaanxi Province, China, Xi'an, 710049, CHINA.
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View Article and Find Full Text PDFActa Bioeng Biomech
June 2024
4Department of Pediatric Dentistry and Preclinical Dentistry, Wroclaw Medical University, Wrocław, Poland.
: Caries or iatrogenic thermal trauma of the teeth have a significant impact on the dental pulp structure connected with stimulation of angiogenesis and lymphangiogenesis. Therefore, the aim of the study was to identify the difference in the rate of heat dissipation by vessels present in the dental pulp. : Freshly extracted healthy ( = 10) and carious ( = 14) molars and premolars were cut on a diamond saw and subjected to active thermographic examination and then subjected to lymphoscintigraphy and X-ray examination.
View Article and Find Full Text PDFJ Mol Model
January 2025
School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou, 450001, People's Republic of China.
Context: SiGe nanotubes (SiGeNTs) hold significant promise for applications in nanosolar cells, optoelectronic systems, and interconnects, where thermal conductivity is critical to performance. This study investigates the effects of length, diameter, temperature, and axial strain on the thermal conductivity of armchair and zigzag SiGeNTs through molecular dynamics simulations. Results indicate that thermal conductivity increases with sample length due to ballistic heat transport and decreases with temperature as phonon scattering intensifies.
View Article and Find Full Text PDFACS Nano
January 2025
Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, P. R. China.
Along with the development of miniaturization, integration, and high power of electronic chips in the 5G and artificial intelligence era and their urgent need for technologies enabled to solve high heat flux dissipation in limited space, investigating bioinspired extreme superwettability surfaces with high-efficiency condensation heat transfer (CHT) performance has attracted great interest in academic and industrial communities. Compared with filmwise condensation of flat hydrophilic surfaces featured with continuous liquid films, dropwise condensation of flat hydrophobic surfaces is a more efficient type of energy transport way. However, discrete condensate drops can only shed off the hydrophobic flat surfaces under gravity until their sizes reach the capillary length of liquid, e.
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