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Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III–V semiconductor technologies. In this CPV⁺ scheme (“+” denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV⁺ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.

Emerging classes ofconcentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV+ scheme (\"+\" denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV+ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.

Nickel-doped titanium dioxide (NIT) with different nickel contents (0.1–1.0 wt%) was prepared via the sol–gel method, combined with mechanical ball milling. X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV–Vis diffuse reflectance spectroscopy (DRS) were employed to characterize the crystalline structure, morphological characteristics, and optical properties of the samples. The photocatalytic activity was evaluated through the photocatalytic degradation of methylene blue (MB) under visible light and nitric oxide (NO) under simulated sunlight. The XRD results show that all the catalysts retain the anatase phase, confirming that nickel doping does not alter the crystalline structure of TiO2. NIT catalysts exhibited a plate-like morphology due to the ball milling treatment of the precursors. The DRS analysis revealed that nickel modification induced a redshift in the absorption edge of TiO2 and enhanced the visible-light absorption. The photocatalytic tests demonstrated that 0.5 wt% NIT and 0.7 wt% NIT exhibited the highest photocatalytic activity for MB degradation, achieving degradation rates of 93.1% and 91.4% after 60 min, respectively. Moreover, 0.7 wt% NIT showed the optimal NO conversion efficiency of 45.4% after 30 min. The improved photocatalytic performance of the sample is attributed to enhanced visible-light absorption, reduced charge recombination, and a high specific surface area. This study provides a facile strategy for synthesizing Ni-doped TiO2 nanoplates based on the sol–gel method, which is scalable in regard to the industrial production of efficient photocatalysts.

Ecosystem light use efficiency (LUE) is a key factor of production models for gross primary production (GPP) predictions. Previous studies revealed that ecosystem LUE could be significantly enhanced by an increase on diffuse radiation. Under large spatial heterogeneity and increasing annual diffuse radiation in China, eddy covariance flux data at 6 sites across different ecosystems from 2003 to 2007 were used to investigate the impacts of diffuse radiation indicated by the cloudiness index (CI) on ecosystem LUE in grassland and forest ecosystems. Our results showed that the ecosystem LUE at the six sites was significantly correlated with the cloudiness variation (0.24 ≤ R(2) ≤ 0.85), especially at the Changbaishan temperate forest ecosystem (R(2) = 0.85). Meanwhile, the CI values appeared more frequently between 0.8 and 1.0 in two subtropical forest ecosystems (Qianyanzhou and Dinghushan) and were much larger than those in temperate ecosystems. Besides, cloudiness thresholds which were favorable for enhancing ecosystem carbon sequestration existed at the three forest sites, respectively. Our research confirmed that the ecosystem LUE at the six sites in China was positively responsive to the diffuse radiation, and the cloudiness index could be used as an environmental regulator for LUE modeling in regional GPP prediction.

Very long chain fatty acids, which accumulate in plasma and tissues in X-linked adrenoleukodystrophy (ALD), neonatal ALD, and the Zellweger cerebrohepatorenal syndrome, are degraded by the peroxisomal β -oxidation pathway, consisting of acyl-CoA oxidase, the bifunctional enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase, and β -ketothiolase. A marked deficiency of all three enzyme proteins was reported in livers from patients with the Zellweger syndrome, a disorder in which peroxisomes are decreased or absent. Peroxisomes are not as markedly decreased in neonatal ALD and appear normal in X-linked ALD. Immunoblot analysis of the peroxisomal β -oxidation enzymes revealed an almost complete lack of the bifunctional enzyme in neonatal ALD liver, similar to the finding in Zellweger tissue. In contrast, acyl-CoA oxidase and β -ketothiolase were present in neonatal ALD liver, although the thiolase appeared to be in precursor form (2-3 kDa larger than the mature enzyme) in neonatal ALD. Unlike either neonatal ALD or Zellweger syndrome, all three peroxisomal β -oxidation enzymes were present in X-linked ALD liver. Despite the absence in neonatal ALD liver of bifunctional enzyme protein, its mRNA was detected by RNA blot analysis in fibroblasts from these patients. These observations suggest that lack of bifunctional enzyme protein in neonatal ALD results from either abnormal translation of the mRNA or degradation of the enzyme prior to its entry into peroxisomes.