Quantitative effect of kerogen type on the hydrocarbon generation potential of Paleogene lacustrine source rocks,Liaohe Western Depression,China

Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source rocks.Lacustrine source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organic carbon(TOC)content,various kerogen types,and a wide range of thermal maturity.Consequently,their hydrocarbon generation potential and resource estimation can be misinterpreted.In this study,geochemical tests,numerical analysis,hydrocarbon generation kinetics,and basin modeling were integrated to investigate the differential effects of kerogen types on the hydrocarbon generation potential of lacustrine source rocks.Optimized hydrocarbon generation and expulsion(HGE)models of different kerogen types were established quantitatively upon abundant Rock-Eval/TOC/vitrinite reflectance(R_(o))datasets.Three sets of good-excellent source rocks deposited in the fourth(Es4),third(Es3),and first(Es1)members of Paleogene Shahejie Formation,are predominantly types I-II_(1),II_(1)-II_(2),and II-III,respectively.The activation energy of types I-II_(2)kerogen is concentrated(180-230 kcal/mol),whereas that of type III kerogen is widely distributed(150-280 kcal/mol).The original hydrocarbon generation potentials of types I,II_(1),II_(2),and III kerogens are 790,510,270,and 85 mg/g TOC,respectively.The Ro values of the hydrocarbon generation threshold for type I-III source rocks gradually increase from 0.42%to 0.74%,and Ro values of the hydrocarbon expulsion threshold increase from 0.49%to 0.87%.Types I and II_(1)source rocks are characterized by earlier hydrocarbon generation,more rapid hydrocarbon expulsion,and narrower hydrocarbon generation windows than types II_(2)and III source rocks.The kerogen types also affect the HGE history and resource potential.Three types(conventional,tight,and shale oil/gas)and three levels(realistic,expected,and prospective)of hydrocarbon resources of different members in the Liaohe Western Depression are evaluated.Findings suggest that the Es3 member has considerable conventional and unconventional hydrocarbon resources.This study can quantitatively characterize the hydrocarbon generation potential of source rocks with different kerogen types,and facilitate a quick and accurate assessment of hydrocarbon resources,providing strategies for future oil and gas exploration.

Performance Characterization of CR/PU Asphalt for Potential Application in Assembled Fast-Repairing Engineering

Conventional repairing methods for asphalt pavement have some inconveniences,such as insufficient strength,and are typically time-consuming.To address these issues,this study proposes a new technological method to design and prepare a high-performance assembled asphalt concrete block for fast repair of the potholes.A series of composite modified asphalt binders with 10%crumb rubber(CR)and different dosages(0%,1%,3%,5%)of polyurethane(PU)are examined to determine the optimized binder.Subsequently,the corresponding asphalt mixtures are prepared for further comparison and assessment of engineering properties,such as moistureinduced damage,high-temperature deformation,and low-temperature cracking characteristics.The test results show that PU can significantly improve the high-temperature performance and hardness of(crumb rubber modified asphalt)CRMA binder;3%PU contributes allowing the resistance of CRMA mixture to moisture-induced damage at higher levels,particularly under water whole immersion;as 3%PU is added,the high-temperature rutting deformation resistance of the CRMA mixture increases significantly,and the low-temperature anti-cracking properties are also improved slightly.Therefore,the innovatively designed high-quality assembled fast-repairing asphalt concrete block is recommended as an appropriate option for highway maintenance.

Development and characterization of novel microsatellite markers for the Common Pheasant(Phasianus colchicus)using RAD-seq

Background: The Common Pheasant(Phasianus colchicus) Linnaeus, 1758 is the most widespread pheasant in the world and widely introduced as a game bird. Increasing needs for conservation genetics and management of both wild and captive populations require permanent genetic resources, such as polymorphic microsatellites in order to genotype individuals and populations.Methods: In this study, 7598 novel polymorphic microsatellites for the Common Pheasant were isolated using a RAD-seq approach at an Illumina high-throughput sequencing platform. A panel of ten novel microsatellites and three existing ones from the chicken genome were multiplexed and genotyped on a set of 90 individuals of Common Pheasants(representing nine subspecies and ten individuals each) and 10 individuals of the Green Pheasant(P. versicolor).Results: These 13 microsatellites exhibited moderate to high levels of polymorphism, with the number of alleles per locus ranging from 2 to 8 and expected heterozygosities from 0.049 to 0.905. The first analysis of the genetic structure of subspecies/populations using a Bayesian clustering approach, implemented in STRUCTURE, showed two genetic clusters, corresponding to both the Green and the Common Pheasant, with further evidence of subpopulation structuring within the Common Pheasants.Conclusion: These markers are useful genetic tools for sustainable uses and evolutionary studies in these two Phasianus pheasants and probably other closely related game birds.

Selectivity control of photocatalytic CO_(2) reduction over ZnS-based nanocrystals:A comparison study on the role of ionic cocatalysts

Taking copper doped ZnS(ZnS:Cu)nanocrystals as the main body of photocatalyst,the influence of different base transition metal ions(M^(2+)=Ni^(2+),Co^(2+),Fe^(2+)and Cd^(2+))on photocatalytic CO_(2)reduction in inorganic reaction system is investigated.Confined single-atom Ni^(2+),Co^(2+),and Cd^(2+)sites were created via cation-exchange process and enhanced CO_(2)reduction,while Fe^(2+)suppressed the photocatalytic activity for both water and CO_(2)reduction.The modified ZnS:Cu photocatalysts(M/ZnS:Cu)demonstrated tunable product selectivity,with Ni^(2+)and Co^(2+)showing high selectivity for syngas production and Cd^(2+)displaying remarkable formate selectivity.DFT calculations indicated favorable H adsorption free energy on Ni^(2+)and Co^(2+)sites,promoting the hydrogen evolution reaction.The selectivity of CO_(2)reduction products was found to be sensitive to the initial intermediate adsorption states.*COOH formed on Ni^(2+)and Co^(2+)while*OCHO formed on Cd^(2+),favoring the production of CO and HCOOH as the main products,respectively.This work provides valuable insights for developing efficient solar-to-fuel platforms with controlled CO_(2)reduction selectivity.

Stem cell characteristics of early colon cancer tissue and their relationship with cell proliferation and invasion

Objective:To study the stem cell characteristics of early colon cancer tissue and their relationship with cell proliferation and invasion.Methods: Colon cancer tissues and adjacent tissues surgically removed in Dongguan People's Hospital between January 2010 and October 2017 were selected as the clinical samples of this study, the protein was extracted to determine the protein expression of tumor stem cell genes USP22, Nanog, Lgr5 and CD44, and RNA was extracted to determine the mRNA expression of cell proliferation genes and cell invasion genes.Results:USP22, Nanog, Lgr5 and CD44 protein expression as well as Rab5A, TBX2, MDM2, TGF-β1, Smad2/3, Vimentin, Rac1 and VEGF mRNA expression in colon cancer tissues were significantly higher than those in adjacent tissues while Bad, Bax and Fas mRNA expression were significantly lower than those in adjacent tissues;USP22, Nanog, Lgr5 and CD44 protein expression in colon cancer tissues were positively correlated with Rab5A, TBX2, MDM2, TGF-β1, Smad2/3, Vimentin, Rac1 and VEGF mRNA expression, and negatively correlated with Bad, Bax and Fas mRNA expression.Conclusion: The activation of stem cell characteristics in early colon cancer can promote the proliferation and invasion of cancer cells.

Characteristics and origin of low-organicmatter carbonate source rocks in the Middle-Upper Ordovician, Tarim Basin, northwestern China

The continually-discovered large volumes of marine hydrocarbons indicate a huge exploration potential within the carbonate rocks of Ordovician in the Tarim Basin,northwestern China.The Middle-Upper Ordovician(O2+3)carbonate source rocks are at a highly mature stage.These rocks presently contain a low amount of total organic carbon(TOC_(pd)≤0.5%)(TOC_(pd) means the present-day TOC).A mass balance approach is used to identify the source rocks that have expelled hydrocarbons.The characteristics and origin of hydrocarbon expulsion from low-TOC_(pd) source rocks are studied,which are significant for oil exploration in the basin.The results showed that a low-TOC_(pd) O2+3 source rock having expelled hydrocarbons was type I and had a very narrow oil window.With a high rock maturity and a high original TOC(TOCo)value exceeding 1%,nearly 80%of the generated hydrocarbons were expelled.The content of gammacerane and C28 steranes in the oil and source rock extracts were relatively lean,with a V-shaped distribution of regular steranes,suggesting a possible genetic relation between the low-TOC_(pd) source rocks and the marine oil in the Tabei area.Hydrogenrich planktonic algae or acritarchs were the main hydrocarbon parent materials,distributed in the subsiding platform-slope facies.Organic matter was preserved under reducing conditions,and source rocks were formed with a favorable kerogen type and a moderate hydrocarbon generation potential.This study illustrates the hydrocarbon expulsion of low TOC_(pd) source rocks in northern Tarim Basin,which is greatly significant for analyzing the genesis of marine crude oil in Tarim Basin,and evaluating the distribution of marine source rocks.This research method is theoretically significant for oil and gas exploration in the same type of highlymature carbonate paleobasins.

Excess Liquidity and Inflation Dynamics in China:1997-2007

The surge in international capital inflows and the remarkable excess liquidity in China between 1997and 2007are examined in the present paper. It is shown that China＇s improved position in terms of foreign exchange purchases, ignited by huge foreign capital inflows, has effectively induced excess liquidity in China. More importantly, by developing an econometric madel for inflation and excess liquidity, the present study demonstrates that excess liquidity has imposed significant pressure on inflation in China over the past 10 years. This finding suggests that excess liquidity in China has not only contributed to the rise in stock prices and the real estate market boom, but also affected the consumer goods market. The potential transmission mechanism of liquidity-driven inflation and policy implications of the findings of this study are discussed.

A joint call for actions to advance taxonomy in China

Taxonomy plays an important role in understanding the origin, evolution, and ecological functionality of biodiversity. There are large number of unknown species yet to be described by taxonomists, which together with their ecosystem services cannot be effectively protected prior to description. Despite this, taxonomy has been increasingly underrated insufficient funds and permanent positions to retain young talents. Further, the impact factordriven evaluation systems in China exacerbate this downward trend, so alternative evaluation metrics are urgently necessary. When the current generation of outstanding taxonomists retires,there will be too few remaining taxonomists left to train the next generation. In light of these challenges, all co-authors worked together on this paper to analyze the current situation of taxonomy and put out a joint call for immediate actions to advance taxonomy in China.

Deeper Attention-Based Network for Structured Data

Deep learning methods are applied into structured data and in typical methods,low-order features are discarded after combining with high-order featuresfor prediction tasks.However,in structured data,ignorance of low-order features may cause the low prediction rate.To address this issue,in this paper,deeper attention-based network(DAN)is proposed.With DAN method,to keep both low-and high-order features,attention average pooling layer was utilized to aggregate features of each order.Furthermore,by shortcut connections from each layer to attention average pooling layer,DAN can be built extremely deep to obtain enough capacity.Experimental results show DAN has good performance and works effectively.