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High penetration of renewable energy is becoming an important development trend in new generation power system. However, frequent extreme weather events and fragile renewable energy sources pose a huge challenge to the power system resilience. As an important support technology of renewables, energy storage system is of great significance in improving the resilience of the power system. In this paper, a resilience enhancement method for power systems with high penetration of renewable energy based on underground energy storage systems (UESS) is proposed. Firstly, a resilience assessment model is established and the influence of extreme weather is quantified as the failure rate of power system components. Secondly, a bi-level optimization model for UESS operation and planning under extreme weather is built, and the life cycle of UESS is considered. Finally, taking the modified IEEE RTS-79 as an example, the optimal scheme for UESS configuration and operation is given, the investment and effectiveness of UESS is also analyzed. The results show that UESS can significantly enhance the power system resilience under extreme weather events.

Continuous monoculture can increase plant morbidity and reduce crop yields. However, the Ganoderma lucidum mushroom possesses unique nutrient acquisition methods and displays an altered response to the generation of reactive oxygen species (ROS). The effects of continuous cropping on G. lucidum remain unclear. Here, we investigated the effects of consecutive monoculture soil on the yield, bioactive components, antioxidant properties, nutrient metabolism, and enzyme activity of G. lucidum. The results showed no significant differences in terms of yield between the control check and treatment groups after 2 years. However, the content of polysaccharides and triterpenoids after 2 years of treatment and the content of total phenols and flavonoids after 3 years of treatment significantly increased. Moreover, the antioxidant activity (AOA) of the polysaccharides under consecutive monoculture soil treatments also significantly increased. These differences were caused by changes in nutrient metabolism and the activities of antioxidant and ligninolytic enzymes. Under continuous monoculture soil treatment, the content of reducing sugars, water-soluble sugars, free amino acids, and water-soluble proteins significantly increased. The activities of superoxide dismutase, manganese peroxidase, and lignin peroxidase increased with the time of continuous monoculture, while the activities of peroxidase, catalase, and laccase decreased. The increase in ligninolytic enzymes was postulated to mediate the ROS scavenging ability of G. lucidum. In conclusion, continuous cropping soil could increase the levels of bioactive components and AOAs of G. lucidum.

Three-inch InGaAs epilayers are grown by solid source molecular beam epitaxy using the manipulator equipped with dual-zone heaters. The effects of the substrate temperature on the uniformity of material surface morphology, indium composition, photoluminescence, electronic mobility, and background doping are investigated. As the temperature of the outer heater in the range of 625 °C to 655 °C, no dim area is observed on the edge of the material surface. At the same time, the indium composition fluctuation of the high-resolution X-ray diffraction and the photoluminescence wavelength fluctuation are less than ±0.1% for the epilayers grown at the optimum substrate temperatures.

Ganoderma lucidum exhibits pronounced anti-inflammatory effects, polysaccharides and triterpenoids are regarded as major constituents displaying the anti-inflammatory activities, whether sterols contribute to this activity remains unclear. Herein Ganoderma lucidum sterols (GLS) were innovatively isolated by a single-step procedure, the profile of GLS was characterized by HPLC-ELSD and shown similar to that of sterols separated by a traditional method, but much higher in content. Furthermore, GLS inhibited inflammation in macrophages by significantly attenuating LPS-induced cell polarization as well as releases and mRNA expressions of pro-inflammatory mediators NO, TNF-α, IL-1β and IL-6. Moreover, the anti-inflammatory activity of GLS was mediated by MAPK and NF-κB pathways, GLS suppressed MAPK pathways by blocking phosphorylation of p38 but not ERK and JNK, which is complementary with inhibitory effects of Ganoderma polysaccharides and triterpenes on JNK and ERK, indicating Ganoderma sterols may exert synergistic anti-inflammatory effect with polysaccharides and triterpenes. GLS also inhibited NF-κB pathways by restraining phosphorylation and degradation of IκB-α and blocking phosphorylation of NF-κB p65. Molecular docking confirmed that sterols of GLS were directly bound to active sites of p38 and p65 to suppress their activation. Therefore, our findings suggest GLS as natural and safe anti-inflammatory agents to prevent and treat inflammatory diseases.

A direct correlation pathway has been established between the material defects and dark currents of InGaAs photodetectors, which is significant for demonstrating the focal plane array with large scale and small pixels. The same photodetector chip was characterized by using emission microscopy and dark current-voltage measurements. The chips with defect emissions perfectly match with those chips showing large dark currents. The defect emissions were observed for the chips with large dark currents, while did not for the chips with low dark currents. The measurement result of the transmission electron microscope reveals that those material defects correlated with the device dark currents were mainly originated from the interface of the substrate and InP buffer layer. This work clarifies the direct correlation of defect types and device performances, which indicates the direction of improving the photodetector materials.

Offshore wind power is a rapidly growing area of electricity in China. In the present paper, interaction mechanisms between the caisson for wind turbines and saturated silt sand are investigated with laboratory tests based on two different installation methods, jacking installation and suction installation. For the jacking installation process, the results indicate that the soil pressures inner and outer the skirt of the caisson vary with a similar feature and the magnitudes of the two are nearly balanced. The tip resistance plays a key role in the total jacking installation resistance. This paper examines the predictive performance of qc method and API approach for jacking installation resistance. It is demonstrated that the qc method provides better predictions. The resistance coefficients are recommended. For the case of suction installation, however, the changes of soil pressures inner and outer the skirt are contrasting. Specifically, the inner pressure and tip resistance fall dramatically, but the outer pressure increases when suction is applied. Seepage effect is found to be an important mechanism for the installation of suction caisson. The reduction ratios of the inner friction and tip resistance follow a power-function with the normalized suction. Based on the test results, a prediction method for the required suction has been developed and evaluated.

High-quality InP is grown by solid source molecular beam epitaxy using white phosphorus source in a three-zone valved cracker cell. The growth temperature, growth rate and substrate desorption process have been adjusted to optimize the structural, electrical and optical properties. The photon and carrier scattering dynamics are investigated by temperature-dependent photoluminescence and electron Hall mobility. The 5-μm-thick sample presents stronger photoluminescence, solo carrier recombination scheme and inferior impurity scattering comparing to the 1-μm-thick sample. The high electron mobility of 137000 cm2/V·s at 77 K has been achieved for the 5-μm-thick InP layer.

Three Schiff bases dissolved in chloroform were investigated to determine their nonlinear optical properties using D4σ Z-scan technique employing 10 ps pulses of Nd:YAG laser at 355 nm. It was found that the highest value of the nonlinear refractive index was obtained for Schiff base with 2-(2-pyridyl)ethylamine. Whereas, a negative nonlinear refractive index was extracted for symmetrical Schiff base with cyclohexanediamine with NO2 group. In addition, the Schiff base thin films were investigated using AFM and SEM/EDX measurements to check their quality and homogeneity, which is necessary in the production of photonic devices.

In this work, we report preliminary results obtained for methacrylic polymers incorporating azobenzene side-group as nonlinear optical (NLO) active molecule. The trans-cis isomerization properties are discussed. The third-order non-resonant nonlinear refractive index (n2) and nonlinear absorption coefficient (β) are measured using the Z-scan technique at 1064 nm in the picosecond regime. The influence of different electron-acceptor groups in azobenzene moieties on the nonlinear properties is investigated.

Taken as an example the Upper Permian reef section on the carbonate platform margin at Ziyun, Guizhou, the paper discusses the missing time of a hiatus surface, an important problem in chemical sequence stratigraphy, with the concept of cosmic chemistry. Then the paper proposes a series of new concepts for chemical sequence stratigraphy, including the condensation surface, relative compaction factor and time missing factor. Finally a quantitative curve of Late Permian relative sea–level change in the Ziyun area is presented with time coordinates.

Tabu search and scatter search (TS & SS) algorithm is proposed to solve vehicle routing problem (VRP) in this paper. Considering the quality of solution and the dispersity of solution in the solution process, dynamic tabu mechanism of algorithm is embedded in the scatter search algorithm, what's more, combination is achieved and new solution is generated through the exchange of both sides of the structure-solution mechanism in reference set, the selection strategy of edge partly comes from RefSet1 and RefSet2, another part is from RefSet1, so as to ensure the diversity and high quality of solution; simulation experiment proves the feasibility and effectiveness of the algorithm.

The aim of this study is to discuss the tectonic position of Baoshan in Yunnan Province, China, during the Late Paleozoic by comparison of the sedimentary facies, fauna and palaeomagnetic data from the Baoshan region with those from the Yangtze region and southern Tibet. The sedimentary facies change suggests that in the Late Palaeozoic the Baoshan region underwent a similar geological history to southern Tibet, but different from that of the Yangtze region. The rugose corals and brachiopods as well as vertebrates of Baoshan are different from those of the Yangtze region during the Late Palaeozoic. An evident segregation seems to exist between them. The Late Paleozoic fauna of Baoshan shows certain similarities to southern Tibet. The Devonian and Late Carboniferous faunas, especially, are very similar to those in southern Tibet. This indicates that there was no evident segregation between them in the Late Palaeozoic. The palaeomagnetic data reveal that in the Late Palaeozoic the Yangtze region was close to the equator, while the Baoshan region and southern Tibet were situated in the middle latitudes. On the basis of the palaeontological, sedimentological and palaeomagnetic data, it is inferred that Baoshan and southern Tibet were situated in the same continental margin, and both regions were far from the Yangtze region during the Late Paleozoic. The Baoshan region may be considered as a massif within the Gondwana tectonic domain which includes southern Tibet, while the Yangtze region was located in another tectonic domain—the South Asian domain, with a wide ocean, the Tethys between them.

The newly introduced imaging Dark-field Z-scan (DFZ-scan) technique is applied here to demonstrate its ability to measure the optical third-order nonlinear (NL) index coefficient in the presence of nonlinear absorption (NLA). We present our experimental results for two compounds of Porphyrin molecules, known to have relatively high NLA in the picosecond regime, at 532[Formula: see text]nm, allowing to test both cases of positive and negative nonlinear refraction (NLR). Moreover, we show that, it is possible to increase the sensitivity of the method by introducing a circular aperture in the image plane. Also, limitations are discussed to process optically a pure NL refractive signal, not subject to the influence of the NLA one, at the output of the imaging setup.

In this paper, a problem is described and mathematical formulation is established on the basis of open vehicle routing problem with soft time windows. Meanwhile, an improved tabu search algorithm (TS) is proposed to optimize the OVRPSTW. in improved TS static, the initial solutions are obtained at random and then current one is selected from better solutions. Two paths are randomly selected on 2-opt to improve solution, ensuring the optimization between and inside the paths. Tabu list's length is expressed by linear Representation to conduct a dynamic tabu list. Thus, the length and the struction of tabu list change with search process diversifying the search path, to expand the scope of neighborhood search, and to improve global optimization. Simulation experiment proved the feasibility and effectiveness of tabu search algorithm.

In 1605 a destructive earthquake affected the northern region of Hainan Island and adjacent parts of the Chinese mainland. Based on a detailed analysis of contemporary chronicles, the authors present a revision of the effects of the earthquake, and show that a sequence of strong shocks throughout 1605 caused cumulative damage and relatively heavy loss of life in Qiongshan. The subsidence of large areas of coast round Puqian Bay and Dongzhai Port is shown to be due to a combination of liquefaction caused by the shock, the occurrence of a typhoon associated with flooding and exacerbated by a high surge tide, as well as a long-term process of active tectonic movement in the area; the subsidence was not caused by downthrow of the earth's crust during the shock. Topographical changes in the area, traced from historical maps, suggest that subsidence is continuing, but a survey of the long-term seismicity of Hainan Island indicates that it is not an area of exceptional seismic risk.

Two epochs of Early Palaeozoic rugose coral diversification, Caradocian-Ashgillian and Middle Llandoverian-Early Wenlockian, are chosen for biogeographical analysis at the generic level, following an overall revised classification of the Rugosa (Wang et al., 1989a). World reconstruction maps are based on palaeomagnetic, palaeotectonic and palaeoblogeographic data, and were constructed through an autograph programme on an IBM PC-AT microcomputer. The Caradocian and Ashgillian rugose corals are in 16 families and 71 genera, including 15% Cystiphyllida, 40% Streptelasmatida and 44% Columnariida, in addition to the zaphrentoidid genus Protozaphrentis . Two biogeographical realms, the West Prototethyan and the East Prototethyan, may be discerned. The West Prototethyan Realm includes three provinces, the Siberian, the North American and the Kazakhstan-Hinganian. The East Prototethyan Realm also includes three provinces, the Southeast Asian (Yangtzean), the East Australian and the North European. The third area, the Gondwanan, is devoid of corals. In Middle and Late Llandoverian and Early Wenlockian, the rugose corals have 27 families and 130 genera, of which 26% are Cystiphyllida, 32% are Streptelasmatida and 41% are Columariida, in addition to the zaphrentoidid genus Duncanella . The West Prototethyan Realm contains three provinces, the Siberia-Mongolian, the North European and the North American. The East Prototethyan Realm consists of two provinces, the Southeast Asian (Yangtzean) and the Kazakhatan-Sinokorean, both bearing Ceriaster and Amplexoides .

The time span of the Proterozoic is taken as from 2600 to 600 Ma with subdivision boundaries at 1850 and 1050 Ma respectively, as 2600 Ma seems more appropriate for the initial Proterozoic in China, Siberia and parts of Gondwanaland, and 600 Ma is an inferred age of the Precambrian–Cambrian boundary based on recent study of the Yangtze Gorge section. The Proterozoic of China includes the Lower Proterozoic Wutaian and Hutuo-an, the Middle Proterozoic Changchengian and Jixianian and the Upper Proterozoic Qingbaikou-an and Sinian.Based mainly on tectono-sedimentary types and associations, seven stratigraphic super-regions are recognized in the Proterozoic of China and stratigraphic successions of various representative regions are shown in two tables, one for the Sinian and another for the Pre-Sinian Proterozoic. Palaeogeographic outline of the main super-regions and chronometric limit of the principal stratigraphic units are briefly discussed. Three types of stable Sinian successions are distinguished, the Yangtze type, the Quruktagh type and the Jiaoliao type, which are correlated mainly on the basis of tillite horizons and of sabelliditids and the Ediacara type of fossils. Semi-stable and mobile types of Sinian deposits in Southeast China are also briefly mentioned.The Proterozoic tectonic units of China and the nature of their boundaries are shown on a sketch map showing basement structures. Crustal sectors of continental nature are designated as continental tectonic domains, while broad and complicated crustal sectors of mainly transitional and partly oceanic nature may be called continental margin tectonic domains. The boundaries between these domains are usually the principal crustal consumption zones. On this basis, three continental domains, the North China, the South China and the Southern (Gondwana), and two continental margin domains, the Northern (Siberian–Mongolian) and the East China, are distinguished. Platforms, continental nuclei, massifs and uplifts are used to denote subdivisions within the tectonic domains. The development of aulacogens is an outstanding feature in the continental domains, especially in the Middle Proterozoic. Aulacogens may be classified into an intra-platform type and a platform margin type. Early Proterozoic aulacogens are usually brachy-axial and intermittent, and show conspicuous deformation at closure, much like a geosyncline. Thirteen aulacogens of different types are shown on the sketch map.The boundary nature of continental domains is analysed in terms of island arcs and marginal seas, and also of emplacement of granite rocks in border parts. The North China Domain was basically consolidated at around 1850 Ma and has a passive northern margin stretching from Nei Mongol to Central Tianshan, but the southern margin was active and was twice subducted by the Qinling marine realm at 1700 and 1000 Ma approximately. The Yangtze Platform was not completely consolidated until 1050 Ma BP but has a core older than 1850 Ma. A broad continental margin terrain had developed in the Jiangnan region and farther to the southeast in the Middle and Late Proterozoic. At least two island arc belts with interarc basins, an inner Fanjingshan and an outer Sibao, may be discerned in the Middle Proterozoic, and a Late Proterozoic island arc zone over 1000 km in length was developed along the southern margin of the Jiangnan Uplift, represented by the Banxi Group and equivalent strata. This kind of broad complicated continental margin tract which has a long development history may be called the open type or the West Pacific type.