Recent trends in artificial photosynthetic system

Solar energy is the most abundant and clean energy on the earth, and developing equipment or devices with high-efficiency solar energy conversion is an effective way to alleviate the energy crisis. The majority of redox enzymes require a coenzyme to provide the hydrogen source needed for the reaction process, and the most commonly used coenzyme is nicotinamide adenine dinucleotide (NADH). However, NADH is expensive and easily decomposed, which greatly limits its application of artificial photosynthetic systems. We review recent progress in the construction of artificial photosynthetic systems that mimic natural photosynthesis

The protoliths to the sillimanite gneisses from the Larsemann Hills and geological implication in their formation

The source rock from which the sillimanite gneisses derive mainly was the biotite plagioclase gneiss in the Larsemann Hills. It is the deformation-metamorphism process under special pressure and temperature condition, not the original rock compositions, that controls the presence of sillimanite. To a great degree, the sillimanite gneiss was the mixture of the detaining materials of the migrating felsic melt from the bt-plagioclase gneiss that underwent partial melting and the relics when the melt was removed. In sillimanitization the original rock had been changed substantially in chemical composition. The related metamorphism process severely deviated from the isochemical series, the process was of, therefore, an open system. In addition, the Al2O3 contents of the original rock was an important, but not critical factor for the formation of sillimanite, i. e. , the sillimanite-bearing rock need not be of aluminum rich in composition, and vise contrarily, the aluminum rock may not produce sillimanite. The authors of the present paper postulate that the source rock from which the aluminum rich rock derives need not be of aluminum rich, but sillimanitization is generally the Al2O3 increasing process. The aluminum rich sediments such as clay or shale need not correspond directly to sillimanite-rich gneisses. No argillaceous rock present equals to sillimanite-rich gneiss in chemical composition. The protoliths to the sillimanite gneisses from the Larsemann Hills, east Antarctica, and their adjacent area may be pelite, shale greywacke, sub-greywacke, quartz sandstone and quartz-tourmalinite. If correct, the conclusion will be of significant implication for the determination of the sillimanite gneiss formation process and the reconstruction of the protolith setting

Characterising the asphalt concrete fracture performance from X-ray CT Imaging and finite element modelling

© 2018 Informa UK Limited, trading as Taylor & Francis Group. Crack distress causes asphalt pavement failure under repeated traffic loading. The objective of this study is to investigate the fracture properties of asphalt concrete through three dimensional (3D) numerical simulation using finite element method (FEM). The parameters and datum utilised for finite element models were captured from a grey matrix, which can be converted from digital images scanned by an X-ray computed tomography (CT) apparatus. Afterwards, the uniaxial compression test was simulated using FEM and was also conducted in laboratory to study the stress distribution and to evaluate the degree of damage during the loading process. Eighteen cylindrical asphalt concrete specimens were prepared with three different types of gradations: asphalt concrete, stone matrix asphalt and open-graded friction course. The uniaxial compression test was carried out on these specimens. Before and after each step, the specimens were scanned using X-ray CT to analyse the crack growth behaviour inside the asphalt concrete and to investigate the effect of gradation on the fracture characteristics. The degree of fracture can be evaluated by data analysis from the grey intensity histogram. The evaluation on asphalt concrete crack properties based on FEM with X-ray CT imaging was found to be practicable and reproducible. Additionally, the gradation was found to be an influential factor affecting the crack propagation of asphalt concrete

The Mode of Promotion Industrial Targeted Poverty Alleviation through Land Circulation in Western Mountainous Region of China—A Case Study of Luquan Yi and Miao Autonomous County in Yunnan Province

In the industrial targeted poverty alleviation, land circulation is a key process. Based on the national strategy of targeted poverty alleviation, this paper combined the industrial development of targeted poverty alleviation with land circulation. According to the field survey on the current situation of land circulation and promotion of the industrial poverty alleviation in the typical project area of Zhongping Village in Zhongping Town and Jiaowuying Village in Jiulong Town in Luquan Yi and Miao Autonomous County in Yunnan Province, it summarized and analyzed the organization and operation mechanism, basic practices and main results of the land circulation and promotion of industrial poverty alleviation model in the typical project area of the county. It also summarized the innovation and successful experience of the model, and then came up with measures to further promote the implementation of the model, so as to provide necessary reference for the implementation of land circulation and industrial targeted poverty alleviation for the poverty-stricken counties in Yunnan Province and similar provinces (cities, regions)

Correlate aggregate angularity characteristics to the skid resistance of asphalt pavement based on image analysis technology

The impact of aggregate morphological characteristics plays a key role in the skid resistance of road surface due to driving safety and cost benefits. The 2nd generation of the Aggregate Imaging Measurement System (AIMS II) and X-ray Computed Tomography (CT) were utilized to evaluate the shape of particles and capture the change in their morphological characteristics. The Los Angeles Abrasion (LAA) Test was also conducted in this paper to investigate the influence of variations in aggregate angularity on the resistant performance of asphalt mixtures. Before and after 100, 300, 500, and 1000 rotations of LAA polishing process, 48 particles from each different size were adopted and measured using AIMS II and XCT to obtain the value of their morphological properties. The parameter gradient angularity (GA) with AIMS II and three-dimensional angularity (3DA) with XCT of aggregate surface area were proposed from these tests. Analysis of Variance (ANOVA) was employed to compare these two image analysis systems. Conventional experiments including the sand patch test and British pendulum test, were applied using the prepared aggregates to establish a correlation between the morphological properties of grains and the parameters related to the skid resistance of asphalt mixtures. It was found that the resistance performance of asphalt mixtures can be well described with a function using the value of morphological properties through regression analysis. The efficacy of the X-ray CT analyzing system was verified to evaluate the performance of asphalt mixture pavement precisely. The changes in morphological characteristics of particles are the main causes for degradation in the skid resistance of asphalt pavement

Industrial Poverty Alleviation Model in Southwestern High-altitude Mountainous Areas of China —— A Case Study of Industrial Poverty Alleviation of Xueshan Township in Luquan County of Yunnan Province through Planting Codonopsis pilosula

Due to the severe restrictions of natural conditions and ecological environment, igh-altitude mountainous areas usually become the "hard bones" in the battle against poverty. Xueshan Township, Luquan Yi and Miao Autonomous County of Yunnan Province, located in the alpine valley of Jinsha River, is a major township with wide and deep poverty, and the incidence of poverty is up to 45.00%. In recent years, Xueshan Township has insisted on the battle against poverty, made effort to develop the Codonopsis pilosula industry, and successfully developed a road to poverty alleviation through C. pilosula industry, and formed a unique industrial poverty alleviation model by the end of 2018, the incidence of poverty dropped to 0.74%. Based on field survey and interview, this paper analyzes and summarizes the specific practices, main results, practical experience and promotion and application measures of the poverty alleviation model of C. pilosula planting industry in Xueshan Township, in the hope of providing certain reference for the targeted poverty alleviation in similar areas in Yunnan Province and other provinces of China

Effect of the oxygen-containing functional group on the adsorption of hydrocarbon oily collectors on coal surfaces

The oxygen-containing functional groups (OCFG) on the coal surface affect the adsorption effect of hydrocarbon oily collectors (HOC). An investigation of the interaction between the HOC and OCFG in the absence and presence of water is conducive to understanding the effect of OCFG type on the adsorption of HOC on the coal surface. In this paper, FTIR analysis was used to analyze the OCFG type of coal surface. The adsorption behavior of HOC on different OCFG surfaces was investigated using molecular dynamics simulation. The results indicated the presence of OCFG such as -OH, -COOH, -C=O, and -COCH3 on the coal surface. In conditions without water, the effect of OCFG on HOC adsorption capability follows the order -COOH > -C=O > -OH > -COCH3. In an aqueous solution, the effect of OCFG on HOC adsorption capability follows the order -C=O>-COCH3>-OH>-COOH. Moreover, the hydrophilicity of OCFG is the key factor that affects the adsorption effect of HOC. In other words, the adsorption effect of HOC on the coal surface in an aqueous solution does not depend on the strength of the interaction between the OCFG and HOC in the absence of water, but on the hydrophilicity of the OCFG. The -COOH and -OH on the coal surface are not conducive to the adsorption of HOC onto the coal surface. Masking the -COOH and -OH of the coal surface is beneficial in improving the coal flotation performance with HOC as a collector

Comparative Metabolomics Study Revealed Difference in Central Carbon Metabolism between Sika Deer and Red Deer Antler

The antler regeneration has been well studied for the past two decades and adopted in the regenerative medicine model for studying on developmental biology. Despite our growing knowledge of functional molecules regulating antler regeneration, we still do not know whether antler from different deer species possess the exact same mechanism or not. Our previous comparative study between sika deer and red deer suggests that the metabolic pathways between them are profoundly different based on protein level. Therefore, the metabolomic technology is used to identify and quantify the metabolites in antler samples, providing interesting insights into differential metabolite profile of antlers between sika deer and red deer. The distinct metabolic characteristics of sika deer compared to red deer provide an opportunity to explain why the red deer antler with a larger size. The enrichment analysis of differential metabolites showed that three pathways including glycine and serine metabolism, methionine metabolism, and pterine biosynthesis had a significant difference between two antler groups

Implications for Rodinia reconstructions for the initiation of Neoproterozoic subduction at ~860Ma on the western margin of the Yangtze Block: evidence from the Guandaoshan Pluton

Neoproterozoic igneous rocks are widespread along the western margin of the Yangtze Block, but their petrogenesis and tectonic setting is debated. The Guandaoshan pluton is located at the southwestern margin of the Yangtze Block and is mainly composed of diorite and subordinate gabbro, with quartz diorite in its margin. Hornblende is an ubiquitous mineral in different phases of the pluton. SHRIMP zircon U-Pb dating of quartz diorite, gabbroic diorite, and gabbro from the pluton yielded 206Pb/238U ages of 857 ± 7 Ma, 856 ± 6 Ma, and 856 ± 8 Ma, respectively. Guandaoshan pluton samples show a large range of SiO2 (47.02-67.66%), MgO (1.12-7.5%), Fe2O3T (2.8-12.22%) and CaO (2.95-11.88%), low rare earth element (REE) contents from 22 to 49 ppm, and enrichment of Sr, Ba and Rb and depletion of Nb, Zr and Ti with characteristics of island arc magma. They also exhibit low initial 87Sr/86Sr ratios from 0.7030-0.7033, and positive εNd(t) values from + 4.8 to + 5.2. These features suggest that the parental magma of the Guandaoshan pluton originated at a convergent plate boundary from a depleted mantle source modified by slab fluids, and underwent the fractional crystallization of amphibole and magnetite, without significant crustal assimilation, during the formation from gabbro-diorite to quartz diorite. Neoproterozoic magmas with age of 860-740 Ma are abundant on the western Yangtze Block, and there is a gap of magmatism in early Neoproterozoic (from about 1000 Ma to 870 Ma). Therefore, it can be deduced that the ~ 860 Ma Guandaoshan pluton and the contemporary magmatism represent initial subduction at the western margin of the Yangtze Block. Based on the Neoproterozoic paleomagnetic data, detrital zircon ages, magmas with low δ18O values in South China and our new data, we prefer that the South China Block was located at the margin of Rodinia in the Neoproterozoic, and not at the center of the supercontinent