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Water conflicts (WACT) in shared river basins have become one of the factors that restrict regional economic development and social stability. Therefore, it is necessary to evaluate water conflict risk (WACR) when managing transboundary river basins. In this research article, in order to accurately and effectively forecast the water conflict risk level, a three-stage process is implemented. Firstly, an evaluation framework for WACR was constructed. The framework consists of four drivers of water conflict: conflict because of water quantity reduction, conflict as a result of differences in water use efficiency, conflict due to disparities in economic and social value of water, and conflict caused by the differences on the amount of water allocated to ensure the integrity of the ecological environment. Secondly, a conflict risk evaluation model was established based on subtraction set pair potential to assess the static evaluation of the WACR. Thirdly, the Grey correlation model is used to forecast data to dynamically predict WACR in the future. The Mekong River Basin (MRB) was selected as a case study to test the validity of the framework. Hence, the following results are obtained: (1) The risk of water conflict in the MRB is always at a medium level. (2) China has the highest risk of water quantity conflict. Laos and Myanmar have a very high water efficiency conflict risk. The risk of economic and social conflict in Cambodia, Myanmar, and Vietnam is at a medium degree. The risk of ecological environmental conflict in Laos and Thailand is at a medium level. (3) From 2022 to 2027, WACT in the MRB decreased to a low risk. Based on this, risk prevention measures are put forward for water cooperation in the MRB. [ABSTRACT FROM AUTHOR]

With the emergence of the Lewis Turning Point and the disappearance of Demographic Dividend, improving production efficiency has become an important issue in China. As a special type of enterprise in China, university spin-offs have both the elements of a state-owned economy and market economy. As the dual attributes of university spin-offs study the effect of enterprise ownership structure and staff structure on labor productivity, this becomes a critical issue. Based on the data of 151 university spin-offs in Hubei Province of China in 2017, this paper constructs a multiple regression model to analyze the impact of property rights and staffing on the labor productivity of employees. The results suggest that the coexistence of multiple staffing structures of university spin-offs is not only detrimental to their own development but also weakens the positive effect of clear property rights on labor productivity. Clarifying the property rights, reducing the number of public institution staff will lead to reforms of the university spin-offs in the future. [ABSTRACT FROM AUTHOR]

The Daliang zinc deposit occurs in the southwestern Xiangxi-Qiandong Zn-Pb metallogenic belt and is located on the southeastern margin of the upper Yangtze block. In this study, we present results from petrographic observations, rare earth elements, C-H-O isotopes, and fluid inclusions. The zinc deposit is hosted by middle Cambrian dolomite. The ore-forming process is divided into three stages from early to late: pyrite-galena, sphalerite-pyrite-dolomite, and dolomite. The characteristics of the REEs suggest that multiple fluids were involved in hydrothermal dolomite precipitation under low-temperature conditions. Two types of hydrothermal dolomite fluid inclusions were identified: pure liquid phase inclusions and liquid-rich phase inclusions. The fluid inclusions of hydrothermal dolomite yield homogenization temperatures of 108–192 °C (average 153 °C), with salinities of 12.3–26.4 wt% (average 23.0 wt%) NaCl equiv. The δ13Cfluid, δDfluid and δ18Ofluid values for ore-forming fluids range from −4.2 to −3.5‰ (mean −3.8‰), −38.8 to −34.3‰ (mean −36.0‰), and 6.2–6.4‰ (mean 6.3‰), respectively. This study demonstrates that ore-forming fluid was sourced from a moderate- to high-salinity basinal brine and leached metals from metasedimentary rocks of the basement in the Yangtze block. The main transportation of ore-forming fluid occurred in the form of chlorine complexes along well-developed faults, and sulfides precipitated with decreases in pressure and temperature, as well as pH changes. Studies of the Daliang zinc deposit suggest that it is a medium- to low-temperature MVT-like deposit. [ABSTRACT FROM AUTHOR]

This paper analyzes and compares the deformation, failure characteristics, and energy characteristics of coal and rock under uniaxial compression. It is considered that the change laws of the total stress–strain relationship curves of raw coal and sandstone samples are similar, and they all exhibit the primary fracture compaction and closure stage, elastic deformation stage, fracture expansion stage and stress drop stage. The failure mode of coal and rock is a predominantly columnar splitting, and the fractured coal and rock bite each other. The ultimate bearing capacity, elastic modulus and peak strain of coal samples are small for sandstone. Under uniaxial compression, the ultimate bearing capacity, elastic modulus, and peak strain of coal samples were 46.17%, 63.32%, and 69.54% of sandstone, respectively. In the compaction stage, the proportion of releasable elastic energy of the coal sample was higher than that of dissipated energy, while that of the sandstone sample is the opposite. The proportion of releasable elastic energy of coal samples in other stages was higher than that of dissipated energy, and more than 80% of the total energy absorbed by coal and rock specimens in the loading process was stored in the form of releasable elastic energy. Other total energy was dissipated by the internal defects of the samples during compaction, sliding and new micro-cracks in the yield stage. [ABSTRACT FROM AUTHOR]

The emergence of a series of problems, such as serious water environment pollution and flood disasters, leads to an increase in an urban water resources system's vulnerability and pressure. In order to alleviate an urban water resources crisis, calculating the water resources system resilience (WRSR) and identifying its impact factors are essential. This paper constructed a resilience evaluation framework of the "Economy-Social Development-Infrastructure-Water Resources-Ecological Environment" water resources system from three stages, i.e. resistance, restoration and adaptability. Then, taking 21 cities along the Yangtze River Economic Belt's lower reaches (YREB's lower reaches) as an example, we scientifically measured the WRSR by using the Projection Pursuit Evaluation Model of Real Coding based on the Accelerating Genetic Algorithm (RAGA-PP) and analyzed its driving factors with Geographic Detectors (GD). (1) From 2010 to 2018, the overall level of the WRSR along the YREB's lower reaches was low, and it was characterized by attenuation from central cities to marginal cities; Suzhou had the highest average WRSR (0.656), while Chizhou had the lowest (0.207). (2) From stage characteristics, compared with 2010, resistance and restoration of most cities along the YREB's lower reaches showed an upward trend in 2018; however, the adaptability level of some cities was still low. From the perspective of sub-system resilience, resilience levels of different sub-systems in each urban water resources system (UWRS) were different. (3) For impact factors, average factor interpretations of per capita GDP, average wages of employees and affected areas of floods, geological disasters and typhoons were largest. Based on this, this paper provides relevant suggestions for improving the WRSR along the YREB's lower reaches to improve ability of UWRS to resist external risks. [ABSTRACT FROM AUTHOR]

PM2.5 is a bad output of China's improved industrialization and rapid economic development, which seriously threatens people's health and greatly hinders the sustainable economic development. Studying the socio-economic driving factors of PM2.5 emissions is of great significance for reducing air pollution and realizing green development. Therefore, based on the simultaneous consideration of space technology differences and time technology progress, this paper constructs an index decomposition analysis-production-theoretical decomposition analysis decomposition model under the global meta-frontier-production theory. Then, we decompose the PM2.5 emission concentration of 30 provinces in China from 2005 to 2018 into nine driving factors and discuss the impact of different factors from the national, regional, and provincial levels. The results reveal that economic activity is still the main factor to promote the increase of PM2.5 emission, but its effect decreases, while the inhibitory effect of catch-up effect on PM2.5 concentration increases gradually. In addition, economic activities have the greatest impact on the East China, while the time catch-up effect has a more significant impact on the Central and Western China. Moreover, the influence of energy intensity effect, space technology catch-up effect, and time technology catch-up effect is gradually increasing, which have become important factors to inhibit the PM2.5 emission. Based on the above results, we put forward relevant policy suggestions. [ABSTRACT FROM AUTHOR]

Under the background that China puts forth the goals of "Emission Peak" and "Carbon Neutrality", heavily polluting corporations as the main source of carbon emissions, whether the restriction of carbon emission disclosure could promote the transformation and upgrading of heavily polluting corporations to raise their value, is a problem worthy of in-depth study. This paper selected listed companies in heavily pollution industries from 2009 to 2019 as the research samples, and analyzed the impact of carbon emission disclosure on short-term and long-term performance based on the perspective of ownership structure heterogeneity. This paper also discussed the moderating effect of carbon emission disclosure on state-owned enterprises and private enterprises taking into account government environmental regulations, media evaluation, and corporate image management based on the Gatekeeper Theory. Firstly, this paper found that in the short term, the improvement of carbon emission disclosure level will inhibit the value growth of enterprises in the initial stage, but will promote the value growth to a certain extent. In the long run, carbon emission disclosure plays a positive role in promoting enterprise value. Secondly, the government environmental regulation, media evaluation, and corporate image management produced different moderating effects under the difference in ownership structure. For state-owned enterprises, the higher the level of government environmental regulations and media evaluation, the more significant is the short-term and long-term value effect. While the higher the level of corporate image management, the more significant is the short-term value effect, however, the long-term value effect is not significant. For private enterprises, government environmental regulations, media evaluation, and corporate image management have no significant moderating effects. Based on the above findings, this paper presents countermeasures and suggestions for the high-quality development of enterprises from the perspectives of government management and enterprise operations. [ABSTRACT FROM AUTHOR]

Identifying the high-quality economic growth pathways under the requirements of water conservation and water pollution reduction is pivotal to realize regional sustainable development. Combined with the theory of resource and environmental value, sustainable development, and environmental accounting, this paper innovatively introduces water resource liability (WRL) to measure water environmental pressure. This study takes the Yangtze River Economic Belt (YREB) as the research area and firstly conducts a spatial–temporal analysis of the WRL change in this region from 2013 to 2018. Then, the Tapio decoupling model is used to analyze the decoupling states and the decoupling stabilities between WRL and economic growth in the 11 provincial areas and 3 sub-regions of the YREB. Finally, the main internal factors affecting the decoupling states are identified from the perspective of decoupling decomposition. The main results show that: (1) The WRL of the YREB increases from 173.36 billion CNY in 2013 to 201.62 billion CNY in 2018, with an increase of 16.3%, showing an upward trend of fluctuation. The WRL of the lower reaches of the YREB is generally higher than those of the upper and middle reaches of the YREB from both the provincial and sub-regional levels. Chongqing has the lowest WRL with an average value of 7.03 billion CNY, while Shanghai has the highest with the average of 28.74 billion CNY. (2) The decoupling state between WRL and economic growth in the YREB is generally stable. The decoupling state of the downstream is better than that of the upper and middle reaches, and the decoupling stability index is 0.59, which is the most stable. (3) The internal influencing factors between WRL and economic development in the YREB include structural effect, technological effect, and silence effect, among which technological effect with the worst decoupling stability is the main driving factor. The findings of this study are crucial for policy makers to formulate targeted policies to decouple WRL from economic growth and to realize sustainable development in the YREB. [ABSTRACT FROM AUTHOR]

To ensure transboundary river basins are protected as a system, forming water environment governance coalitions is important. However, accurate determination and allocation of the payoffs of joint environment governance under uncertain conditions is a challenging task. This study used a triangular fuzzy number to describe the payoff and solve the fuzzy allocation problem. The article also considered the importance of different coalitions and the effectiveness of the distribution. In addition, the authors constructed a multi-weight fuzzy allocation quadratic programming model and proposed an analytical solution to determine the triangular fuzzy allocation payoffs. These contributions were used to allocate the coalition payoff of basin-wide environment governance, and the Zhanghe River Basin is used as a case study. The results showed that the model produces outputs comparable with the Shapley value allocation method. Therefore, the proposed methodological framework can be used as an alternative allocation scheme that provides a reasonable solution during uncertainty. [ABSTRACT FROM AUTHOR]

The Three Gorges Reservoir area (TGRA) has complex geological conditions and a fragile ecological environment. The construction of the Three Gorges Project triggered ecological and environmental issues and social disputes, which have attracted considerable attention in recent years. However, how the temporal and spatial characteristics of ecosystem service value (ESV) in the TGRA changed in each stage of the Three Gorges Project with the implementation of ecological restoration plans remains ambiguous. Based on four periods of land use data from 2000 to 2018, the changes in land use were investigated, and the ESVs were estimated. Then, the spatial distribution and dynamic changes in ecosystem services were analysed. The results showed that grassland and construction land were the land use types that had the greatest reductions and increases in area over time, respectively. The conversion of cropland to forestland, grassland and construction land represented the most important land type changes. In the past 18 years, because of an increase in forestland and water area, the ESVs increased by 2.7 billion yuan, with a growth rate of 3.46%. The conversion of cropland to forestland had the largest contribution rate to the increase in ESV. The ESV was higher in the northeast and lower in the southwest, and its changes had a significant positive autocorrelation in terms of the spatial distribution. The hot spots of ESV change were mainly distributed in the main stream of the Yangtze River and the reservoir area. This research provides a reference for land resource allocation and experience for the ecological environment protection and sustainable development of the Yangtze River Basin. [ABSTRACT FROM AUTHOR]

Colletotrichum gloeosporioides is one of the most common and serious fungal diseases of the tree Mangifera persiciforma. Yet we lack an effective method to evaluate this ecological interaction accurately. Here, we measured the functional traits and leaf reflectance spectrum of the host plants under different disease degrees. The findings provide a fast and efficient method for large-scale and high-precision monitoring of C. gloeosporioides in M. persiciforma stands. Using the collected leaf reflection data, we set up a prediction model of the optimal disease degree. Firstly, we found that leaf functional traits of M. persiciforma generally consisted of low leaf thickness, low relative chlorophyll content, small specific leaf area, high leaf tissue density, high dry matter content, low stomatal density, and large stomatal area. Secondly, leaf reflectivity increases with damage of C. gloeosporioides, which corresponds to five main reflection peaks and five absorption valleys in the spectral reflectance curve of leaves at the same positions (350–1800 nm). Thirdly, with the increase of infection degree, red edge slope and yellow edge slope decrease, while green peak reflectance, red valley reflectance, and blue edge slope all increase. Blue shift was detected in the red edge, green peak, and red valley, while red shift appeared at the blue edge and yellow edge. Finally, the best predictive model was that based on green peak reflectance (y=3.6396–0.0693x, R2=0.5149, RMSE [root-mean-square error] =0.2735), with an R2=0.92 and RMSE=0.0042 between its predicted vs. observed values. Because of its high inversion accuracy, the model can be used to predict the invasion conditions of M. persiciforma by C. gloeosporioides. Our study demonstrated that when plants are infected by C. gloeosporioides, there was a strong trade-off relationship between leaf functional traits. On the global leaf economics spectrum, the leaves tended toward the "slow investment-return" end when infected by C. gloeosporioides. [ABSTRACT FROM AUTHOR]

Recently, exploring the driving factors behind carbon emission (CE) change in China has achieved increasing attention. As the determinants of CEs are likely to be affected by both spatial and temporal heterogeneities, we propose an extended production-theoretical decomposition analysis (PDA) approach based on global meta-frontier data envelopment analysis (DEA) to resolve heterogeneity problem. Then, by combing the extended PDA and index decomposition analysis (IDA) approaches, CE changes are decomposed into nine factors. And using panel data from China's 30 provinces during 2005–2015, the main results provide findings as follows. (1) The national total CEs are continuous increasing from 2005 to 2012, and then remain stable in 2012–2015. (2) Potential energy intensity and carbon emission temporal heterogeneity result in reduction of CEs. (3) Economic activity is the dominant driving factor for increasing the CEs, while temporal catch-up effect of carbon emission helps decrease the CEs in almost all provinces. [ABSTRACT FROM AUTHOR]

Logistics service as an important key link between online take-out platform and offline users. Its quality directly affects customer service perception and experience, but also lead to the heart of the willingness of consumers to re-use. So a framework constructed for understanding logistics service quality on consumers' behavioral psychology is focused on, suitable service encounter points (function encounter, the distributor encounter, service results encounter, word-of-mouth encounter have been identified from the literature and the connotation of service encounter in logistics service. In view of the limitations of traditional statistical analysis methods in dealing with Likert scale data and the fuzziness of scale evaluation grade, a combination of statistical analysis and fuzzy comprehensive evaluation is used to analyze the scale. Then combined with the logical connection between perceived value, customer satisfaction and behavioral psychology in the classic American Customer Satisfaction Index Model model, emotional attachment of platform as the adjustment variable. The findings indicate that the four encounter points of online take-out logistics service are positively related to customer purchase satisfaction and perceived value. Additionally, the most significant impact on the perceived value is the functional encounter and the distributor encounter, and the most significant impact on the customer satisfaction is the service results encounter and word-of-mouth encounter; platform emotional attachment positively regulates the positive correlation between perceived value/customer satisfaction and behavioral psychology. So this research extends the theory of service encounter to online delivery logistics service quality evaluation, which is a further expansion of the connotation of service encounter and provides the platform with suggestions to pay attention to the flaw of logistics service and improve service. [ABSTRACT FROM AUTHOR]

Urban plants can improve several environmental pollution problems in cities, especially dust prevention, noise reduction, purification of the atmosphere, etc. To explore the influence of dust deposition on the spectral characteristics of the leaf, a foliar dust deposition prediction model based on high-spectrum data was established. Taking Euonymus japonicus L., the common greening tree species in Beijing, as the research object, high (T1), medium (T2), and low (T3) dust pollution gradients were set and hyperspectral data were collected. Results showed that: (1) in the dust-contaminated environment with different concentrations, the trend of the reflectance curve of the leaves of Euonymus japonicus L. was generally consistent. The spectral reflectance of the leaf surface was positively correlated with the amount of leaf dust. (2) There were five obvious reflection peaks and five main absorption valleys with the same positions and ranges in the 350–2500 nm range. (3) The spectral reflectance of leaf flour dust particles of Euonymus japonicus L. was significantly different before and after dusting, and its size was generally clean leaves > dust-depositing leaves. The sensitive range of its spectral response was 695–1400 nm. (4) The overall trend of the first derivative spectrum was basically the same. The red edge slope and the blue edge slope appeared as T3 > T2 > T1, the red edge position and the blue edge position appeared as T1 < T2 < T3. The red edge position of the leaf surface after dust deposition had an obvious "blueshift", and the moving distance increases with the increase of dust retention on leaf surface. (5) The leaf water index (y = − 1.18x2 + 0.5424x + 0.9917, R2 = 0.8030, RMSE = 0.187) had the highest accuracy in the regression model of leaf surface dust deposition using spectral parameters. The test showed that the R2 reached 0.9019, which indicated that the model has a good fitting effect. This prediction model can effectively estimate the dust deposition of the leaf surface of Euonymus japonicus L. [ABSTRACT FROM AUTHOR]

Roll bonding is an effective method to fabricate dissimilar laminated metal composites (LMCs). Therefore, investigation of the microstructure evolution during the roll bonding process is very important to improve the bonding strength and optimize the roll bonding process. In this work, a rolling stuck test was executed to obtain the roll bonding deformation zone. The microstructure and interface morphology of an Al/Ti/Al LMC were investigated during the roll bonding process, and the growth of the diffusion intermetallic compounds was characterized for the annealed LMCs. The results show that the critical roll bonding reduction is greater than 20% for the fabrication of Al/Ti/Al LMCs. The change in the bonding interfacial morphology from straight to wavy is related to the uncoordinated deformation between the constituent layers. When annealing at 550°C, the kinetic exponent of about 0.5 for Al3Ti reveals that the diffusion mechanism obeyed the parabolic growth law in diffusion thickness. [ABSTRACT FROM AUTHOR]

In this article a three-stage framework is proposed for allocating water and welfare in transboundary river basins under water scarcity. The proposed allocation framework combines the bargaining theory with resource allocation and bankruptcy games. The water bankrupt Euphrates River was taken as a case study to demonstrate the applicability of the allocation framework. The results showed that the total monetary welfare that can be generated by reallocating the water in order of decreasing water productivity value of each riparian country is greater by 43.43% of total monetary warfare that can be made if each country were to utilize the water allocated to it independently. The proposed allocation framework rewarded Turkey, Syria and Iraq with welfare assignments which are 41.5%, 42.1% and 57.45% greater than what they could have achieved by unilaterally utilizing the water allocated to them. Generally, the proposed water allocation, water reallocation and welfare assignment framework provide some insights for allocating transboundary water in a way which is efficient, fair and sustainable. [ABSTRACT FROM AUTHOR]

As much as transboundary river basins can be niches for regional cooperation, they could also be causes for interstate water disputes. The risk of water conflict in these river basins is much higher during water scarcity. As a result, establishing a fair and efficient water allocation mechanism is key for the sustainable sharing of these river basins' water. In this paper, the authors propose a monotonic water allocation mechanism for transboundary river basins under water scarcity by coupling the bankruptcy theory with the Asymmetric Kalai-Smorodinsky bargaining solution concept. The allocation framework takes into account the aspiration water claims of the sharing countries. Additionally, as a case study, the allocation solution was used to allot the contested water of the Nile among the basin countries. For the medium term water demands the framework allocated 61.67%, 89.80%,91.82% and 61.67% of their water claims to Ethiopia, Sudan, Egypt and to the assumed coalition countries on the White Nile referred in this paper as equatorial states (Uganda, Kenya, Tanzania, Burundi, Rwanda, and Democratic Republic of Congo) respectively. On the other hand, for the long term demands, the allocation scheme allocated 63.65%, 69.36%, 71.42% and 60.41% of their water demands to the riparian countries in the same order. In general, the authors hope that the water allocation scheme applied in this article can contribute to the ongoing efforts to design river sharing solutions to river sharing problems in transboundary river basins by understanding the strategic interaction among riparian countries. [ABSTRACT FROM AUTHOR]

Transboundary river basins are one of the main sources of fresh water which are facing water scarcity. When transboundary water is contested not only the allocation outcomes matter but also the allocation process should possess a certain desirable properties such as flexibility and sustainability. Therefore designing a mechanism that possesses these desirable characteristics and allocates the contested water resource is important as well. This article proposed a water allocation framework by combining the bankruptcy theory with asymmetric Nash bargaining solution concept for solving the water sharing problem in transboundary river basins under scarcity. Furthermore, the allocation framework was applied to the Nile river basin and to a hypothetical water scarce transboundary river basin. The results obtained were then compared with the allocation outcomes from classical bankruptcy allocation rules. The results showed that the proposed method can provide insights which could be useful for obtaining water allocation outcomes which are easier to implement and enforce under water scarce conditions. [ABSTRACT FROM AUTHOR]

Most of the transboundary river basins are contested due to the overlapping water demands of their riparian countries. Hence, these border crossing river basins are under immense pressure from the rising water demand. Thus, most of these essential fresh water resources could face water bankruptcy scenario in the future. The Nile river basin is one of these contested river basins. The demand for the river's water is rising rapidly. Research studies indicated that the river basin could become water bankrupt in the near future. In this article the authors applied the classical bankruptcy water allocation rules for allocating the predicted available water of the river basin. In addition, the authors proposed an innovative way of accounting the water contribution of riparian states and also a mechanism for weighing the water deficit allotted to them. Generally, the authors hope that this article shades some light on allocation of water under water scarcity in the Nile river basin and in other border crossing river basins which could help for avoiding water conflicts and ensuring the sustainability of these crucial freshwater resources. [ABSTRACT FROM AUTHOR]

It has been confirmed that the key source rocks of Qiongdongnan Basin are associated with the Yacheng Formation, which was deposited in a transitional marine-continental environment. Because the distribution and evolution patterns of the source rocks in the major depressions are different, it is important to determine the most abundant hydrocarbon-generation depressions in terms of exploration effectiveness. Based on an analysis of organic matter characteristics of the source rocks, in combination with drilling data and seismic data, this paper establishes a model to evaluate the hydrocarbon-generation depressions in the deepwater area of Qiongdongnan Basin. First of all, by using the method of seismic-facies model analysis, the distribution of sedimentary facies was determined. Then, the sedimentary facies were correlated with the organic facies, and the distribution of organic facies was predicted. Meanwhile, the thickness of source rocks for all the depressions was calculated on the basis of a quantitative analysis of seismic velocity and lithology. The relationship between mudstone porosity and vitrinite reflectance ( Ro) was used to predict the maturity of source rocks. Second, using the parameters such as thickness and maturity of source rocks, the quantity and intensity of gas generation for Yacheng and Lingshui Formations were calculated. Finally, in combination with the identified hydrocarbon resources, the quantity and intensity of gas generation were used as a guide to establish an evaluation standard for hydrocarbon-generation depressions, which was optimized for the main depressions in the Central Depression Belt. It is proposed that Lingshui, Ledong, Baodao and Changchang Depressions are the most abundant hydrocarbon depressions, whilst Songnan and Beijiao Depressions are rich hydrocarbon depressions. Such an evaluation procedure is beneficial to the next stage of exploration in the deep-water area of Qiongdongnan Basin. [ABSTRACT FROM AUTHOR]

Over the past several years, a number of hydrocarbon reservoirs have been discovered in the deepwater area of Qiongdongnan Basin, northwestern South China Sea. These oil/gas fields demonstrate that the evolution of the deepwater sedimentary environment are controlling the formation and distribution of large-scale clastic reservoirs. Integration between seismic and borehole data were necessary to best clarify the distribution and quality of these deepwater reservoirs. Geochemical and paleobiological evidence from discrete samples was also applied to document specific information regarding the sedimentary environment. Results show that the Qiongdongnan Basin has existed as a thriving marine environment since Oligocene, when several rifting depressions developed throughout the entire Qiongdongnan Basin. Triggered by the faults activities, several distinct provenances supplied the coarse sediments, transporting and depositing them in deep parts of the rifting depressions. A fan delta system then formed nearby the source in the deeper area of these rifting depressions. The sedimentary environment of Qiongdongnan gradiationally became deepwater since early Miocene. Consequently, abundances of sediments were transported from Hainan Island and Southern Uplift, and then sunk into the basin center. The submarine fans revealed by many boreholes in this area verified them as good reservoir. Because the area reached its lowest sea level at late Miocene and the Southern Uplift subsidenced under sea level, not providing any sediment, so that the carbonate mesa and biorhythms characteristic of this area also developed during this period. In the west part of Qiongdongnan Basin, sediments transported from Vietnam increased in response to the Tibetan Uplift. Consequently, a central canyon developed along the center of Qiongdongnan Basin, which has been confirmed by several boreholes as a favorable hydrocarbon reservoir. The clarification of the deepwater sedimentary environment's evolution is potentially highly beneficial to future hydrocarbon exploration in the deepwater area of Qiongdongnan Basin. [ABSTRACT FROM AUTHOR]

Owing to the fact that the coal-beds are with the characteristics of multi-beds, thin single-bed, rapid lateral changes and deep burial, coal-bearing source rocks are difficult to be identified and predicted, especially in the lower exploration deepwater area. In this paper, a new integrative process utilizing geology and geophysics is proposed for better predicting the distribution of coal-bearing source rocks. Coal-beds were identified by the logging responses of 'three higher, three lower, and one expand' and carbargilite were recognized by the characteristics of 'four higher and one lower'. Based on the above logical decision, coal-beds and carbargilite can be distinguished automatically by cluster analysis of logging curves in verticality. Within the constraints of well-seismic calibration, the coal-beds group also can be detected in horizontality by the integrated representation of 'negative phase, higher Q, lower impedance and lower frequency' within the seismic data. However, the distribution of coal-bearing source rocks utilizing geophysical methodology may do not conform to the geological rules of coal accumulation. And then the main geological controlling factors of coal accumulation are comprehensively analyzed as follows: (1) Paleotopography and tectonic subsidence determine the planar range of terrestrial-marine transitional facies markedly; (2) The relative sea level changes affect the accommodation space and shoreline migration, and limit the vertical range of coal-beds. More specifically, the relationship between the accommodation creation rate and the peat accumulation rate is a fundamental control on coal accumulation. The thickest and most widespread coals form where those two factors reached a state of balance; (3) The supply of autochthonous clasts and the distance between deposition places and paleovegetation accumulated area are the critical factor to form abundant coal, which means that if deposition area is close to paleouplift, there would be sufficient organic matters to form abundant source rocks. The results show that the integrated methods can significantly improve prediction accuracy of coal-bearing source rocks, which is suitable for early exploration of western deepwater area of South China Sea. [ABSTRACT FROM AUTHOR]

In the Qiongdongnan Basin, faults are well developed. Based on the drilling results, the traps controlled two or more faults are oil-rich. However, when only one fault cut through the sand body, there is no sign for hydrocarbon accumulation in the sandstone. In terms of this phenomenon, the principle of reservoir-forming controlled by fault terrace is proposed, i.e., when the single fault activates, because of the incompressibility of pore water, the resistance of pore and the direction of buoyancy, it is impossible for hydrocarbon to accumulate in sandstone. But when there are two or more faults, one of the faults acts as the spillway so the hydrocarbon could fill in the pore of sandstone through other faults. In total five gas bearing structures and four failure traps are considered, as examples to demonstrate our findings. According to this theory, it is well-advised that south steep slope zone of Baodao-Changchang Depression, south gentle slope zone of Lingshui Depression, north steep slope zone of Lingshui Depression, and north steep slope zone of Baodao Depression are the most favorable step-fault zones, which are the main exploration direction in next stage. [ABSTRACT FROM AUTHOR]

Using regional geological, newly acquired 2D and 3D seismic, drilling and well log data, especially 2D long cable seismic profiles, the structure and stratigraphy in the deep-water area of Qiongdongnan Basin are interpreted. The geometry of No.2 fault system is also re-defined, which is an important fault in the central depression belt of the deep-water area in the Qiongdongnan Basin by employing the quantitative analysis techniques of fault activity and backstripping. Furthermore, the dynamical evolution of the No.2 fault system and its controls on the central depression belt are analyzed. This study indicates that the Qiongdongnan Basin was strongly influenced by the NW-trending tensile stress field during the Late Eocene. At this time, No.2 fault system initiated and was characterized by several discontinuous fault segments, which controlled a series small NE-trending fault basins. During the Oligocene, the regional extensional stress field changed from NW-SE to SN with the oceanic spreading of South China Sea, the early small faults started to grow along their strikes, eventually connected and merged as the listric shape of the No.2 fault system as observed today. No.2 fault detaches along the crustal Moho surface in the deep domain of the seismic profiles as a large-scale detachment fault. A large-scale rollover anticline formed in hanging wall of the detachment fault. There are a series of small fault basins in both limbs of the rollover anticline, showing that the early small basins were involved into fold deformation of the rollover anticline. Structurally, from west to east, the central depression belt is characterized by alternatively arranged graben and half-graben. The central depression belt of the Qiongdongnan Basin lies at the extension zone of the tip of the V-shaped northwestern ocean sub-basin of the South China Sea, its activity period is the same as the development period of the northwestern ocean sub-basin, furthermore the emplacement and eruption of magma that originated from the mantle below the Moho surface occurred at the region between Songnan-Baodao and Changchang sags, from east to west with the early-stage spreading of the South China Sea. Therefore, this study not only helps in depicting the structural features and evolution of the deep-water basin in the Qiongdongnan Basin, but also provides the geological and structural evidence for establishing a unified model of continental margin extension and oceanic spreading. [ABSTRACT FROM AUTHOR]

A discrete centrosymmetric (HO)(CHOH) binary cluster was confined in the cavity of a metal-ligand hybrid [Ag(bpda)(bpp)·14HO·2CHOH] ( 1) (where bpp = 1,3-bis(4-pyridyl)propane and H2bpda = 2,2′-biphenyldicarboxylic acid). The novel mixed water-methanol cluster consists of one grail-shaped hexadecameric cluster, four dangling water and four hanging methanol molecules. The (HO) cluster is composed of two pairs of edge-sharing (HO) rings attached to one (HO) core with twenty hydrogen bonds. Alternatively, the (HO) cluster is structurally similar to a complicated hydrocarbon generated by undergoing [2+2] cycloaddition of 1,2,3,4,5,6-hexahydropentalene, which reveals the resemblance between water clusters and organic compounds. [ABSTRACT FROM AUTHOR]

However, we have some concerns in regards to their study conclusion: the authors claimed intermediate cervical plexus block (CPB) using 0.2 ml/kg of 0.25% ropivacaine at the C4-5 intervertebral level did not cause ipsilateral hemidiaphragmatic paresis. Postoperative nausea and vomiting (PONV) and pain are two common adverse outcomes exhibited during this period [[3]]. From the discussion above, the current study by Kim et al., does not provide convincing evidence that intermediate CPB using 0.2 ml/kg of 0.25% ropivacaine at the C4-5 intervertebral level did not cause ipsilateral hemidiaphragmatic paresis. [Extracted from the article]

Electrochemical behavior of (C70)2- p-tert-butylcalix [8] arene film on a glassy carbon electrode has been studied by cyclic voltammetry. Two pairs of reduction/reoxidation waves were detected in a mixed solvent of acetonitrile and water containing tetra- n-butylammonium perchlorate as the supporting electrolyte. [ABSTRACT FROM AUTHOR]

To quantitatively reflect the relationship between dust and plant spectral reflectance. Dust from different sources in the city were selected to simulate the spectral characteristics of leaf dust. Taking Euonymus japonicus as the research object. Prediction model of leaf dust deposition was established based on spectral parameters. Results showed that among the three different dust pollutants, the reflection spectrum has 6 main reflection peaks and 7 main absorption valleys in 350–2500 nm. A steep reflection platform appears in the 692–763 nm band. In 760–1400 nm, the spectral reflectance gradually decreases with the increase of leaf dust coverage, and the variation range was coal dust > cement dust > pure soil dust. The spectral reflectance in 680–740 nm gradually decreases with the increase of leaf dust coverage. In the near infrared band, the fluctuation amplitude and slope of its first derivative spectrum gradually decrease with the increase of leaf dust. The biggest amplitude of variation was cement dust. With the increase of dust retention, the red edge position generally moves towards short wave direction, and the red edge slope generally decreases. The blue edge position moved to the short wave direction first and then to the long side direction, while the blue edge slope generally shows a decreasing trend. The yellow edge position moved to the long wave direction first and then to the short wave direction (coal dust, cement dust), and generally moved to the long side direction (pure soil dust). The yellow edge slope increases first and then decreases. The R2 values of the determination coefficients of the dust deposition prediction model have reached significant levels, which indicated that there was a relatively stable correlation between the spectral reflectance and dust deposition. The best prediction model of leaf dust deposition was leaf water content index model (y = 1.5019x − 1.4791, R2 = 0.7091, RMSE = 0.9725). [ABSTRACT FROM AUTHOR]