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Volatiles including water on the Moon has been one of the most interesting scientific objects for decades. In this study, we systematically introduced a concept for China's Chang'E−7 (CE-7) lunar polar exploration mission which consists of five elements, the orbiter, lander, rover, and leaper, and one relay satellite. The orbiter will provide a high-resolution image preparing for landing site selection. We also proposed three phases for in-situ investigation after landing. (1) The rover and leaper will jointly investigate the sunlit area; (2) the leaper will explore cold traps; and (3) the leaper will fly back to the sunlit area and continue an extended exploration mission. An experimental penetrator launched by the lander will penetrate permanently shadowed crater walls for water ice detection. Data will be transmitted to Earth through the relay satellite due to the limited Earth visibility. We also calculated the illumination rate within a 15 × 15 km area that partially covers the Shackleton crater at a high spatial resolution of 20 m/pixel during lunar southern summer. Specifically, we compared two potential landing sites with accumulated illumination at different altitude levels, slopes, and distances to the target. We found that one part of the Shackleton crater rim can be a primary landing site for CE-7's both sunlit areas and cold trap explorations. • We introduce a concept design of China's Chang'E−7 lunar polar exploration mission. • The mission element leaper is newly designed to explore water ice at cold traps. • We calculate illumination rates near the Moon's south pole during southern summer. • Engineering safety and scientific goals constrain polar landing site selection. [ABSTRACT FROM AUTHOR]

Research on animal health economics has emphasised the importance of accounting for the indirect economic effects of animal disease outbreaks. Although recent studies have advanced in this direction by assessing consumer and producer welfare losses due to asymmetric price adjustments, potential over-shifting effects along the supply chain and spill-overs to substitute markets have been under-examined. This study contributes to this field of research by assessing the direct and indirect effects of the African swine fever (ASF) outbreak on the pork market in China. We employ impulse response functions estimated by local projection to calculate the price adjustments for consumers and producers, as well as the cross-effect in other meat markets. The results show that the ASF outbreak led to increases in both farmgate and retail prices but the rise in retail prices exceeded the corresponding change in farmgate prices. Furthermore, beef and chicken prices also rose, demonstrating the spill-over impacts of the outbreak to other markets. Overall, the evidence illustrates that a disruption in one part of a food system can have significant ripple effects across other parts of the system. • Animal disease outbreaks constitute a significant and increasing threat to food systems. • Impulse response functions used to capture cross effects within and between systems. • The effect on consumers was twice than on producers, displaying an over shifting effect. • The price of other markets also increased, displaying spillover effects into the system. • A disruption in one part of the system can have important ripple effects in other parts. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Xuefengling lithium polymetallic deposit is a superlarge pegmatite deposit. • Micas and columbite-group minerals from the Xuefengling pegmatites magmatic-hydrothermal process similar with the Bailongshan pegmatites, they may have originated from the same parental magma chamber. • The Xuefengling pegmatites show lower degree of fractionation than the Bailongshan pegmatites. The Xuefengling rare metal pegmatite deposit is located in the West Kunlun orogenic belt, Northwest China. It is one part of the Bailongshan orefield, which is located 5 km southeast of the Bailongshan deposit, and it is composed of the Xuefengling, Xuepen, Longmenshan and Shuangya ore segments. The Xuefengling pegmatite and the Bailongshan pegmatite have similar zoning characteristics, and the pegmatite-hosted rare metal mineralization is approximately 206–213 Ma. On the basis of detailed observations and characterization of the textures and mineral assemblages of pegmatites in the Xuefengling deposit, four zones are identified: a quartz–spodumene (QS) zone, quartz–albite–muscovite (QAM) zone, quartz–albite–tourmaline (QAT) zone, and block albite–quartz pegmatite (BAQ) zone. We use the textures and major and trace element compositions of muscovite and columbite-group minerals from the Xuefengling pegmatite to illustrate both the existing state of rare elements and the origin of the Xuefengling pegmatite. Our results show that from Li-poor (QAM and QAT zones) to Li-rich pegmatites (QS zone), the K/Rb and K/Cs ratios of muscovite gradually decrease from 41.6 to 10.9 and 2276 to 208, respectively, and the Mn# values of columbite-group minerals increase from 0.35 to 0.49, which are similar to the progressive evolution trend identified in Bailongshan pegmatites. However, the lower K/Rb and K/Cs ratios of muscovite from the Xuefengling pegmatites than those from the Bailongshan pegmatites indicate that the Xuefengling pegmatites may have formed from the lower degrees of fractional crystallization of the same parental magma chamber, leading to the Bailongshan ore-field pegmatites gradually strengthening their evolution from east to west. [ABSTRACT FROM AUTHOR]

Concerns about reducing waste gas emissions and the trade-off with economic development dominate government policy worldwide. However, existing data envelopment analysis does little to permit understanding of how environmental efficiency can be improved by learning solutions. Digesting and following effective strategies from elsewhere is intuitive, but to date no evidence has been able to quantify how exactly the inputs and outputs of production are affected. Developing an improved slacks-based measure model, which incorporates learning effects as one part of undesirable outputs for the first time, we reappraise the performance of Chinese regional industrial production systems. Learning effects have significant impacts for three waste gases, especially for sulfur dioxide, advocating policy which gives managers and operatives access to best practice and empowers them to replicate this within their own firms. As well as reducing output there is strong potential to improve environmental efficiency, particularly in the developed eastern area of China. However, in the central and western regions of China it remains optimal to focus efforts on productivity and there caution on placing too much hope on learning activities is cautioned against. We also find that the proposed approach accompanied with traditional data envelopment analysis model can effectively identify the regional inefficiency whether sourced from learning activities, other production activities, or the both. [ABSTRACT FROM AUTHOR]

Since the housing marketization reform, China's real estate industry has rapidly developed and commercial housing prices have risen sharply. The main reason for this is the speculative demand for housing, which breaks the equilibrium of supply and demand, leading to housing prices deviating from their basic value. The housing market in China is not isolated by province, since speculative behavior in one part of the country can affect other regions. This paper analyzes the spatial relevance in housing prices among different provinces in China by calculating Moran's I index and by measuring the speculation degree through spatial autoregressive model (SAR), a spatial economic model combined with a spatial weight matrix. For commercial housing speculation degree measurement and comparison, 31 provinces in China were chosen along with the following variables: housing prices, personal disposable income, one-year personal housing mortgage rates, housing prices growing rates, the rent, amount of residential investment, and the construction areas of houses. The results show that China's housing prices have a clear interaction among the selected cities, and that housing speculation behavior also influences each other in space. Although there are speculation activities in China, from a global perspective the degree of speculation, which varies from region to region, is still just within internationally acceptable limits. Although there are some regions with high degrees of housing speculation, the speculation is not yet China-wide. [ABSTRACT FROM AUTHOR]

Continental shale is abundant with unconventional oil and gas and has considerable potential for exploitation. However, due to differences in the deposition environment, continental shale presents unique characteristics in terms of mineralogy and mechanical properties compared to marine shale. Furthermore, the mechanical influence of fracturing fluid immersion must be considered because of the dual effects on the productive shale system caused by fracturing fluids remaining in the formation. In this study, tri-axial compression tests were performed on Jurassic continental shale specimens collected from an exploratory well (2778–2816 m deep) in the Sichuan Basin of China before and after exposure to fracturing fluids. Meanwhile, two quantitative indicators, the roughness R , which characterizes the widely distributed yield deformation, and the complexity F , which evaluates the complex multi-fractures, were used to distinguish the different brittle-plastic characteristics of specimens before and after fracturing fluid immersion. The results showed that the immersion of fracturing fluids weakened the mechanical properties of continental shale. Two types of fracturing fluid immersion effects were distinguished by the statistics of the failure characteristics of the different layers: lubrication-dominated and softening-dominated. Unlike conventional smooth tri-axial stress-strain curves, many of the post-peak curves were in a 'step-like' shape, corresponding to two sources: one part came from the formation of multi-fractures (brittle characteristics), and the other part came from the softening deformation of main failure surface (plastic characteristics). A new brittleness index, BI new , was proposed considering failure characteristics with different brittleness effects, which could effectively distinguish the brittleness difference before and after exposure to fracturing fluids. • Mechanical variations of continental shale along longitudinal profile were studied. • Different effects of fracturing fluids were distinguished by failure characteristic. • Different sources of additional energy dissipation were recognized. • New brittleness index was proposed incorporating different failure characteristics. [ABSTRACT FROM AUTHOR]

A-type granites are a spectrum of especial felsic rocks that are produced commonly within an extensional environment. They are rare before middle Paleoproterozoic but present abundantly since the late Paleoproterozoic, probably indicating a causal change of tectonics and geodynamic mechanism in the continental evolution of the Earth. An early Mesoproterozoic A-type granite belt was recognized in the southern margin of the North China Craton (NCC) in recent decades. The occurrence of this type of rocks indicates a possible spatial–temporal link between the tectonic evolution of the NCC and the breakup of the Columbia supercontinent during the Mesoproterozoic. The Zhangjiaping granitic pluton is located in the southern margin of the NCC and one part of the A-type granite belt. It can be divided into three zones according to their textural and compositional differences of the rocks with a gradually increasing degree of evolution inwards: wall zone, intermediate zone and core zone. LA-ICP-MS zircon U–Pb dating shows that it was emplaced at ca. 1.53 Ga. Petrologically, the Zhangjiaping granites contain perthite and calcic amphibole but are lack of alkali mafic minerals. Geochemically, all the Zhangjiaping granitic rocks show an affinity to fractionated aluminous A-type granites, with enrichment in silicon and total alkali, and depletion in MgO, CaO and P 2 O 5 with negative Eu, Sr and Ti anomalies, as well as high FeOt/MgO, TiO 2 /MgO and Ga/Al ratios and high HFSEs (i.e., Zr, Nb, Ce, Y) concentrations. Such signatures, along with their low ε Hf ( t ) values (−12.5 to −4.0) of all the granites from the Zhangjiaping pluton, obviously indicate that the Zhangjiaping aluminous A-type granites were derived from partial melting of the crustal calc-alkaline granitoids (i.e., the granodiorites of the Taihua Complex in the study area) and experienced fractional crystallization during magmatic evolution. Their generation would be related to the underplating of mafic magmas in an extensional regime. Integrated with regional data, the Zhangjiaping aluminous A-type granites were the products of anorogenic magmatism likely corresponding to the breakup of the Columbia supercontinent. [ABSTRACT FROM AUTHOR]

This paper reports one part of an ethnographic case study on a Sino-Canadian transnational education programme in southern China. The framework of multiliteracies pedagogy elucidates data collected from classroom observations and teacher interviews. Key findings relate Chinese and Canadian teachers' efforts to nurture emerging global citizens' multilayered linguistic and cultural identities in response to the school's hybrid Sino-Canadian curriculum. Data also intimate literacy teachers' power negotiations pertaining to modality, regional/international languages, the school's imbalanced emphasis on English curricula, and local and global accountability models by building in multiple literacy practices and modes of representations to cater to students' diversified needs. [ABSTRACT FROM AUTHOR]

Coal particles regularly flow into coalbed methane (CBM) wells with the formation water. Once they settle down in the bottom of CBM wells, the pump will get stuck and the reservoir will be buried. In conventional oilwells, sand cleanout is usually operated by circulating the cleaning fluid into the wellbore to bring sand particles to the surface. However, when applied in CBM wells, this traditional hydraulic particles hoisting technology would leak the working fluid into the formation, destroy the coalbed formation structure and jam the formed channel of gas because the bottomhole pressure (BHP) is low. In this paper, a continuous vacuum cleanout technology will be introduced, and it combines a novel jet pump with a concentric tubing string (CTS) to remove coal particles without placing hydrostatic loads on the reservoir. The novel jet pump has two nozzles and the CTS is assembled by the outer tubing and inner tubing. More specifically, a high pressure working fluid is pumped through the CTS annulus from the surface and then it is divided into two parts. One part of the fluid acts as the sand carrier fluid. The other part acts as the power fluid of the jet pump to create a localized drawdown which vacuums the carrier fluid together with coal particles into the jet pump, and then circulates coal particles to surface through the inner tubing. The detailed structure and the principle of the technology system are described, while a theoretical model is built to design and optimize the system which is based on the coal particles transport experiment data and the jet pump theory. The field applications have proved that the coal particles cleanout technology makes significant improvements in achieving high efficiency and preventing leakage in CBM wells, and more importantly, reduces the skin damage and improves the CBM production. [ABSTRACT FROM AUTHOR]

To constrain the provenance of the Ordos Basin and the evolution history of the Qinling Orogen Belt from the Triassic to the Jurassic, 10 samples from the Dongsheng area and 28 samples from the Yan’an area were analyzed for U–Pb ages and Lu–Hf and Sm–Nd isotopic compositions. The results indicate that Middle Jurassic sediments in the Dongsheng area were derived from the Khondalite Belt, Langshan Mountain and the Yinshan Terrane. Mesozoic sediments in the Yan’an area consist of two parts. One part is derived from the North China Craton (NCC), which has U–Pb age groups of ∼1.8 Ga and ∼2.5 Ga, and Hf model ages of ∼2.8 Ga. The other part is derived from the Qilian–Qinling Orogenic Belt, which has U–Pb age groups of 600–1500 Ma and 100–500 Ma, and Nd and Hf isotopic model ages of less than 2.2 Ga. Combining the U–Pb ages with the Hf and Nd isotopic model ages, Mesozoic detrital zircons with U–Pb age groups of ∼1.8 Ga and ∼2.5 Ga in the Yan’an area are found to also be derived from the Khondalite Belt, Langshan Mountain and the Yinshan Terrane, not from the Trans-China Orogen Belt. From the late–Late Triassic sediments of the Yan’an area, the low average values of the Hf (2.03 Ga) and Nd (2.03 Ga) model ages and the characteristic age population of 600–1500 Ma reveal that the main collision or continental subduction between the NCC and the South China Craton (SCC) occurred in the late–Late Triassic. After the main collision or continental subduction, the proportion of sediments from the Qinling–Qilian Orogenic Belt began to decrease (recorded in the early Jurassic samples), which may be in response to the gradual slowing of the uplift speed of the Qinling Orogenic Belt. In the early-middle Jurassic, the sediments have a main U–Pb age population of 100–500 Ma, low detrital zircon Hf model ages (average value is 1.17 Ga) and low whole rock Nd model ages (average value is 1.13 Ga), which suggests that the Qilian–Qinling Orogenic Belt may have a fast uplift history in the early-middle Jurassic. [ABSTRACT FROM AUTHOR]

Highlights: [•] The tuff from the Macaoyuan Group was formed at 1157±19Ma. [•] The maximum depositional age of the Macaoyuan Group is not older than 1180Ma. [•] “Macaoyuan conglomerates” are made up of the slope carbonate gravity flow deposits. [•] The Macaoyuan Group is one part of the basement strata beneath the rift succession. [•] ∼2.60Ga peak age represents an important period for the Yangtze block's formation. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we focused on the retrieval of the LAI in an alpine wetland located in western part of China in late August and early July 2011. A two-layer canopy reflectance model (ACRM) was used to establish the relationships between the LAI and the reflectance of near-infrared (NIR) and red (RED) wavebands. The reflectance data were derived from Landsat TM L1T product and the Terra and Aqua MODIS 16-day and 8-day composite reflectance products (MOD/MYD09) at 250m resolution. Due to the lack of the information about some major input parameters for ACRM, which are sensitive to model outputs in the reflectance of NIR and RED wavebands, the inverse problem was ill-posed. To overcome this problem, a method of increasing the sensitivity of the LAI while reducing the influence of other model free parameters based on the study of free parameters’ sensitivity to the ACRM outputs and the region''s features was studied. The area of interest was divided into two parts using the approximately statistic normalized difference vegetation index (NDVI) value around 0.5. One part was sparse vegetation (0.1

Abstract: This paper studies the diversified investment of China''s foreign exchange reserves from a new perspective of energy strategy. A model is designed to analyze investment strategy of Chinese sovereign wealth fund (SWFs) based on specific investment objective to maximize national welfare, regarding SWFs as one part of China''s energy strategy. The theoretical analysis and simulation suggest that the strategy sovereign wealth fund can increase the national welfare. As an instrument to hedge the risk of national economy, strategy sovereign wealth fund prefers to invest in the strategic industry such as petrol and metal industries aboard. The more the strategy sovereign wealth fund hedges the risk, the more the whole national welfare increases. [Copyright &y& Elsevier]

Abstract: Using both TIMS and SHRIMP methods, U–Pb isotopic dating was carried out on zircons from eclogites and their host gneisses in the Xitieshan area of the north Qaidam mountains, western China. Zircons from both eclogites and retrograded eclogites with metamorphic characteristics gave ages of 485–500Ma, representing the age of eclogite facies metamorphism. Euhedral zircons from the eclogites, which show a magmatic character (Th/U>1), yielded ages of 750–800Ma, which are believed to represent the magmatic crystallization age of the protlith. TIMS dating of zircons from granitic gneiss enclosing retrograded eclogite gave an upper intercept age of 952±13Ma and a lower intercept age of 478±44Ma. The former probably represents the magmatic crystallization age of the granitic protolith, and the latter is in agreement with the age of metamorphic zircons from the eclogite within the margin of error. This implies that the eclogites and their enclosing gneisses in Xitieshan area as a whole underwent HP–UHP metamorphism during an early Paleozoic orogeny to form one part of the north Qaidam HP–UHP metamorphic belt. These results also suggest an ‘in situ’ rather than ‘tectonic''relationship between the eclogites and their host gneisses. [Copyright &y& Elsevier]

The pre-Jurassic geotectonics in Northeast China and its adjacent regions are characterized by collision of microcontinental blocks. The Yanbian region lies between the North China block (NCB) and the Khanka block (KB). Along the Dashanzui–Antu–Kaishantun collision belt, the Yanbian pre-Jurassic fold belt can be divided into two parts. One part represents the western margin of the KB, which consists of Late Proterozoic metamorphic basement and a Permian active continental margin. The other one is located at the eastern margin of the NCB and is composed of Proterozoic passive margin deposits, where the Seluohe and Qinglongcun groups are developed, and rocks of the Permian passive margin. Collision of these two parts took place along the Dashanzui–Antu–Kaishantun collision zone during the Late Permian to Early Triassic, as evidenced by the emplacement of syncollision granites and A-type granites. In northeast China and adjacent regions, a series of microcontinental blocks collided with one other from the end of Early Paleozoic to the Early Triassic. The collision event that took place in the Yanbian region may represent the latest collision event in the Paleo-Asian oceanic domain. [Copyright &y& Elsevier]

Lake eutrophication has become a serious environmental problem in China. Manipulations covering more elements of trophic pyramid are methods for lakes to obtain clear water state and should be studied in detail. In the present study, Meishan Dongpo Lake was divided into two parts, and a combined biomanipulation project was conducted in one part (RLake), and the other part was used as a control (CLake). Species of submerged-plant, fish, macrobenthos, and zooplankton were screened and a certain number of them were added to adjust the eco-chain in RLake. After restoration, the coverage of submerged macrophytes reached >85%; zooplankton greater than 0.6 mm in size increased in number, and the ratio of zooplankton biomass to chlorophyll-a (Chl-a) concentration increased. The dominant fish species changed, and disturbance of the sediment was reduced. The average density of mollusks in RLake was 111.5 ± 19.8 ind m−2, which was much higher than that in CLake (36.7 ± 2.1 ind m−2). Water quality and clarity were substantially improved, and nutrient concentrations, particularly total phosphorus, total nitrogen, and Chl-a were significantly reduced. The aquatic community parameters were negatively correlated with the nutrient parameters and Chl-a. The ecological restoration have adjusted the aquatic ecosystem in RLake, and many positive feedback effects among the aquatic communities made them remove internal nutrients and Chl-a more efficiently. Image 1 • A field combined biomanipulation was conducted with a control. • Submerged macrophyte and aquatic animal communities were constructed. • Positive feedbacks within the groups make the lake remove nutrients efficiently. • Submerged macrophytes indirectly affected Chl-a through TN and TP. • T he water quality and clarity substantially improved. [ABSTRACT FROM AUTHOR]

China is the largest power producer and consumer and has the largest installed capacity of wind turbines (WTs) worldwide. In the last two decades, China's installed capacity of WTs has exploded, significantly impacting its wind power (WP) industry and promoting the development of the industry globally. This paper examines China as one part of the world and elucidates its role, status, and impact on global WP development from a global perspective. Research indicates that China has become the global leader in WP, its WP development has greatly promoted the growth rate of global WP, and it has become an indispensable force in global WP development. However, the comprehensive capability of China's WP generation is not only lower than that of other major WP countries but also lower than the global average. China's WTs have low global recognition and are difficult to export. In addition, the proportion of WP in China's power structure is lower than that of most other major WP countries. Fortunately, these gaps between China and other major WP countries are gradually narrowing. The goal of this paper is to help researchers and investors better understand China's situation and to provide a reference for the rational investment in and development of China's WP. • China has become a global wind power leader, but only in the installed capacity. • China's wind turbines have low recognition in global, and difficult to export. • Comprehensive capability of China's wind power is lower than that of global average. • Currently, China's wind power mainly wins in terms of quantity rather than quality. [ABSTRACT FROM AUTHOR]