mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Superconductivity in potassium and ammonia co-intercalated FeSe_(1-x)Te_x

The origin of the ∼40 and ∼30 K superconducting phases in the metal-intercalated FeSe superconductors is still unclear. We report the synthesis of K_(0.3)(NH_3)_y(FeSe_(1-x)Te_x)_2 and K_(0.6)(NH_3)_y(FeSe_(1-x)Te_x)_2 with x=0-0.6 by using the liquid ammonia method at room temperature. The superconducting transition temperature T_c of the former remains about 43 K for all the nominal Te content less than 0.3, while that of the latter is about 30 K and obviously decreases with Te doping. Superconductivity disappears for x ≥0.4 in both systems. Except for the different chemical pressure induced by substitution of Te for Se in both systems, we also observed distinct external pressure effect on superconductivity for both systems, with much more efficiency of suppressing Tc by external pressure in the former system. These dramatic differences of both chemical and external pressure effects on Tc between the ∼30 and ∼40 K superconducting phases revealed that the existence of the two superconducting phases can be ascribed to the moderate and negligible coupling between FeSe layers, respectively.
Torsional mechanics of single walled carbon nanotubes with hydrogen for energy storage and fuel cell applications

Torsional mechanics of single walled carbon nanotubes (SWCNTs) encapsulated with hydrogen molecules was investigated in this study, using the molecular dynamics (MD) simulation approach. The torsional properties of hydrogen stored SWCNTs were crucial for determining the durability and lifetime of SWNCTs-based energy storage and proton exchange membrane fuel cell (PEMFC) applications. The influence of hydrogen storage concentration, SWCNT geometry, vacancy defects, temperature variation and varying boundaries of rotated as well as fixed groups on the torsional mechanics of SWCNT was investigated. The results and conclusions provide an insight into the torsional properties of SWCNTs with hydrogen storage that could be used for the development of SWCNTs-based hydrogen storage devices and PEMFC applications.
Using big data to track marine oil transportation along the 21st-century Maritime Silk Road

China's designation of the “21st-century Maritime Silk Road” (MSR) region is of extraordinary significance to its maritime rights, transportation security, and socio-economic development. We developed a technical framework allowing the use of “big data” derived from the Automatic Identification System (AIS, an automatic ship-tracking network) for two purposes: the accurate mapping of oil tanker trajectories and the creation of heat maps showing the relative use of oil tanker routes and marine shipping chokepoints. We then applied these methods to 1.5 billion AIS records collected within the MSR in 2014 to statistically identify and analyze busy routes, areas, and chokepoints in this strategic region. Our results demonstrate that the proposed framework can provide an effective analysis of oil movements based on large-scale AIS datasets, helping researchers and policy makers better understand the footprint and strategic implications of maritime oil transportation in the MSR region.
Alter martensitic phase transformation kinetics by forming Ni-rich nanolayer in metastable austenitic steels

A 5 nm Ni-rich nanolayer has been introduced along nanoscale martensite/austenite phase boundaries (PBs) by one-step lowtemperature annealing treatment of cold-rolled meta-stable austenitic steels. Control experiments reveal that the martensitic phase transformation kinetics can be significantly altered by presence of the nanolayers. The growth of pre-existed martensites is substantially suppressed while the martensite nucleation in austenites is less affected, as revealed by a statistical investigation on the martensite size distribution under different tensile strains. Enhanced strength and excellent ductility have been achieved simultaneously in the annealed samples, demonstrating that PBs can be effectively engineered to achieve optimized mechanical properties.
Temporal variation of major nutrients and probabilistic eutrophication evaluation based on stochastic-fuzzy method in Honghu Lake, Middle China

Honghu Lake, which is listed in the Ramsar Convention, was found to be contaminated with elevated nutrients to a certain extent. This study investigated the seasonal variation of major nutrients and probabilistic eutrophic state in surface water from Honghu Lake. Average concentrations of total nitrogen (TN), total phosphorus (TP), chlorophyll-a (Chl-a), chemical oxygen demand (CODMn) and transparency (SD) in summer and winter generally exceeded Grade III of the Chinese environmental quality standards for surface water (GB 3838-2002), with the exception of CODMn in winter. Mean concentrations of Chl-a and CODMn in summer were higher than that in winter, while mean concentrations of TN, TP and SD were slightly higher in winter. The improved probabilistic comprehensive trophic level index (PTLI) method based on stochastic-fuzzy theory was established to evaluate the eutrophic state in Honghu Lake. Compared with the Monte-Carlo sampling method, the Latin Hypercube sampling (LH-TFN) method was selected for the evaluation simulation due to its efficiency and stability. Evaluation results indicated that mean PTLI in summer (69.70) and winter (61.96) were both subordinated to Grade IV (Medium eutrophication). The corresponding reliability of eutrophication level subordinating to Grade IV in summer was of relatively low reliability (51.27%), which might mislead decision makers to some extent and suggest recheck. The probabilistic eutrophication level in summer developed with a trend from medium to severe eutrophication. Sensitivity analysis illustrated that CODMn and Chl-a were the priority pollutants in summer, with the contributions to PTLI of 43.3% and 22.5% respectively. Chl-a was the priority pollutant in winter, with the contribution to PTLI up to 51.3%.
One-step synthesis of robust carbon nanotube foams with ultrahigh surface area for high-performance lithium ion battery

A novel three-dimensional (3D) carbon nanotube foams (CNTF) with ultrahigh specific surface area have been fabricated through a unique but facile one-step synthesis by using CO_2 as both carbon source and activating agent. The activation temperature and time have been adjusted, and the best sample demonstrates a specific surface area of 1959.8 m~2 g~(-1) and a total pore volume of 3.23 cm~3 g~(-1). A reversible capacity of about 870 mAh g~(-1) is maintained at 50 mA g~(-1) when the CNTF used as cathode materials. Meanwhile, the capacity is as large as 320 mAh g~(-1) at the current density of 2 A g~(-1)and the capacity retention is nearly 100% after 500 cycles. These excellent and highly stable battery performances should be attributed to the structural advantages of as-synthesized CNTFs generated by using a facile CO_2-assisted strategy, which may potentially be applied in large scale production of porous 3D carbon materials in the fields of energy storage and conversion.
Causes and underlying dynamic processes of the mid-winter suppression in the North Pacific storm track

Baroclinic wave activity in the North Pacific exhibit peaks in late fall and early spring,and a local minimum in midwinter,when by linear baroclinic instability theory it should attain its maximum.This counterintuitive phenomenon,or “midwinter suppression” (MWM) as called,is investigated with a functional analysis apparatus,multiscale window transform (MWT),and the MWT-based theory of canonical transfer and localized multi-scale energetics analysis,together with a feature tracking technique,using the data from the European Centre for Medium-Range Weather Forecasts ReAnalysis (ERA-40).It is found that the MWM results from a variety of different physical processes,including baroclinic canonical transfer,diabatic effect,energy flux divergence,and frictional dissipation.On one hand,baroclinic canonical transfer and diabatic effect achieve their respective maxima in late fall.More transient available potential energy is produced and then converted to transient kinetic energy,resulting in a stronger storm track in late fall than in midwinter.On the other hand,in early spring,although baroclinic instability and buoyancy conversion are weak,energy flux convergences are substantially strengthened,leading to a net energy inflow into the storm track.Meanwhile,frictional dissipation is greatly reduced in spring;as a result,less transient energy is dissipated in early spring than in midwinter.It is further found that the weakening of baroclinic canonical transfer in midwinter (compared to late fall) is due to the far distance between the storm and the jet stream (located at its southernmost point),which suppresses the interaction between them.Regarding the increase in energy flux convergence in early spring,it appears to originate from the increase (enhancement) in the number (strength) of storms from the upstream into the Pacific.
Carbon emissions induced by farmland expansion in China during the past 300 years

Scientific assessment of the accounting over carbon in the terrestrial ecosystem in the process land use/land cover changes caused by human activities will help reduce the uncertainty in estimating carbon emissions from the terrestrial ecosystem.This study employs a bookkeeping model to estimate the carbon emissions from farmland reclamation in China during the past 300 years based on the annual rate of land use changes (derived from historical natural vegetation,farmland data),preset carbon density and coefficients of disturbance curves.We find out that:(1) there was a net increase of 79.30×10~4 km~2 in national farmland;about 65% of reclaimed farmland had been forest land and 26% of that had been grass land previously;(2) the total amount of carbon emissions from farmland expansion in China had been between 2.94 and 5.61 Pg with the median 3.78 Pg during the past 300 years;specifically,carbon emissions of vegetation were 1.58 Pg while those of soil ranged from 1.35 Pg to 4.03 Pg with the median 2.20 Pg;(3) carbon emissions vary greatly across various ecosystems:the emissions were most from forest land,and then grass land and swamps,and the least from shrubs;deserts functioned more likely to be carbon stock in the process of land reclamation;(4) along the time line,carbon emissions had decreased first and then increased while the peak emissions occurred in the first half of 20th century;and spatially,carbon emissions were most released in Northeast and Southwest China;Northwest China was of the minimum carbon emissions.
Comparisons of urban-related warming in Beijing using different methods to calculate the daily mean temperature

To evaluate the contribution of urban surface expansion to regional warming using different methods to calculate the daily mean surface air temperature (SAT), satellite-based images displaying urban surface expansion over the past 37 years (1980-2016) across China were collected for use in nested numerical experiments using the weather research and forecasting (WRF) regional climate model. The contribution of urban surface expansion to urban-related warming was determined using the daily mean SAT averages based on four time records each day (00, 06, 12, and 18 h UTC, T4) and averages of the SAT maximum (Tmax) and minimum (Tmin) (Txn). The contribution of urban surface expansion to urban-related warming (relative value) in Beijing was 0.110°C per decade (22.8% of total warming) for T4 and 0.094°C per decade (20.2%) for Txn. The values obtained when using T4 were larger than those obtained when using Txn. Differences in the urban-related warming calculated using T4 and Txn could be attributed to the smaller changing trends in Txn in the urban-surface expansion experiment, which resulted from a large changing trend in Tmin and a much smaller changing trend in Tmax. The changes in the diurnal cycle of the energy budget due to urban surface expansion induced changes in the diurnal cycle of SAT, as evidenced by the four time records each day, as well as Tmax and Tmin. This was especially true for periods of intense urban surface expansion, although the annual mean SAT calculated using Txn was larger than that calculated using T4. The increase in impervious area (walls, streets, etc.) due to urban surface expansion, as well as the widespread use of building materials with a large heat capacity resulted in a marked increase in ground heat flux in the daytime. This restricted the increase in SAT in the daytime, but promoted it at night. The increases in SAT due to urban surface expansion were not symmetrical, being smaller in the daytime and larger at night.
The intrinsic nonlinear multiscale interactions among the mean flow,low frequency variability and mesoscale eddies in the Kuroshio region

Using a new functional analysis tool,multiscale window transform (MWT),and the MWT-based localized multiscale energetics analysis and canonical transfer theory,this study reconstructs the Kuroshio system on three scale windows,namely,the mean flow window,the interannual-scale (low-frequency) window,and the transient eddy window,and investigates the climatological characteristics of the intricate nonlinear interactions among these windows.Significant upscale energy transfer is observed east of Taiwan,where the mean Kuroshio current extracts kinetic energy from both the interannual and eddy windows.It is found that the canonical transfer from the interannual variability is an intrinsic source that drives the eddy activities in this region.The multiscale variabilities of the Kuroshio in the East China Sea (ECS) are mainly controlled by the interaction between the mean flow and the eddies.The mean flow undergoes mixed instabilities (i.e.,both barotropic and baroclinic instabilities) in the southern ECS,while it is barotropically stable but baroclinically unstable to the north.The multiscale interactions are found to be most intense south of Japan,where strong mixed instabilities occur;both the canonical transfers from the mean flow and the interannual scale are important mechanisms to fuel the eddies.It is also found that the interannual-scale energy mainly comes from the barotropically unstable jet,rather than the upscale energy transfer from the high frequency eddies.
The scientific connotation of oil and gas formations under deep fluids and organic-inorganic interaction

As a relatively stable craton block in the earth system,the petroliferous basin is influenced by the evolution of the earth system from the early development environment of source rocks,hydrocarbon formation,and reservoir dissolution to hydrocarbon accumulation or destruction.As a link between the internal and external factors of the basin,deep fluids run through the whole process of hydrocarbon formation and accumulation through organic-inorganic interaction.The nutrients carried by deep fluids promote the bloom of hydrocarbon-generating organisms and extra addition of carbon and hydrogen source,which are beneficial to the development of high-quality source rock and enhancement of the hydrocarbon generation potential.The energy carried by the deep fluid promotes the early maturation of the source rock and facilitates the hydrocarbon generation by activation and hydrogenation in high-mature hydrocarbon sources.The dissolution alteration of carbonate rocks and clastic reservoirs by CO_2-rich deep fluids improves the deep reservoir space,thus extending the oil and gas reservoir space into greater depth.The extraction of deeply retained crude oil by deep supercritical CO_2 and the displacement of CH4 in shale have both improved the hydrocarbon fluidity in deep and tight reservoirs.Simultaneously,the energy and material carried by deep fluids (C,H,and catalytic substances) not only induce inorganic CH4 formation by Fischer-Tropsch (F-T) synthesis and “hydrothermal petroleum” generation from organic matter by thermal activity but also cause the hydrothermal alteration of crude oil from organic sources.Therefore,from the perspective of the interaction of the earth’s sphere,deep fluids not only input a significant amount of exogenous C and H into sedimentary basins but also improve the reservoir space for oil and gas,as well as their enrichment and accumulation efficiencies.
Differentiations of geographic distribution and subsistence strategies between Tibetan and other major ethnic groups are determined by the physical environment in Hehuang Valley

The people of the Tibetan Plateau have received extensive attention from scholars because of their unique adaptability to the low temperature and anoxic environments.However,the Tibetan communities and their habitats in the low-altitude regions of the plateau have rarely been studied in a scientific manner.Based on the extraction of geographic information of 197 towns in the Hehuang Valley and on variance analysis,this study examines the habitats and subsistence strategies of the Tibetans and other major ethnic groups in the low-latitude region of the Tibetan Plateau.Our statistical results show that the annual average temperature of Tibetan habitats in the Hehuang Valley is relatively high.The relatively warm environment of the valley allows the Tibetans in that area to cultivate wheat and barley and raise cattle and sheep-a subsistence strategy significantly different from that of other Tibetans in the high-altitude regions in the Tibetan Plateau.In addition,the Tibetan communities in the Hehuang Valley include similar agri-pastoral ethnic groups (including Hui and Salar),both of which adopt similar subsistence strategies.The agricultural ethnic groups (Han and Tu) live in a relatively cool and humid environment facilitating agricultural production,while the agri-pastoral ethnic groups (Tibetan,Hui,and Salar) inhabit relatively warm and arid environment in the valley.Due to the lack of agricultural activities,agri-pastoral groups must also engage in animal husbandry to supplement their diet.In the Ando Tibetan region,the subsistence strategies of the ethnic groups are closely related to their physical environment.Those ethnic groups communicate among themselves,integrate,and influence each other,resulting in a diversified culture.This study proves that the habitat variation at a regional scale corresponds significantly to the variation of subsistence strategies.Our findings may further refine knowledge about the human-environmental relationships of Tibetans and lead future research towards using quantitative methods to analyse the intersection of physical environment and ethnic groups’ distribution.
Characterization of a LAL-type regulator NemR in nemadectin biosynthesis and its application for increasing nemadectin production in Streptomyces cyaneogriseus

Nemadectin,a macrocyclic lactone antibiotic,is produced by Streptomyces cyaneogriseus ssp.noncyanogenus.A methoxime derivative of nemadectin,moxdectin,has been widely used to control insect and helminth in animal health.Despite the importance of nemadectin,little attention has been paid to the regulation of nemadectin biosynthesis,which has hindered efforts to improve nemadectin production via genetic manipulation of regulatory genes.Here,we characterize the function of nemR,the cluster-situated regulatory gene encoding a LAL-family transcriptional regulator,in the nemadectin biosynthesis gene cluster of S.cyaneogriseus ssp.noncyanogenus NMWT1.NemR is shown to be essential for nemadectin production and found to directly activate the transcription of nemA1-1/A1-2/A2,nemC and nemA4/A3/E/D operons,but indirectly activate that of nemG and nemF.A highly conserved sequence 5′-TGGGGTGKATAGGGGGTA-3′ (K=T/G) is verified to be essential for NemR binding.Moreover,four novel targets of NemR,including genes encoding an SsgA-like protein (TU94_12730),a methylmalonyl-CoA mutase (TU94_19950),a thioesterase of oligomycin biosynthesis (TU94_22425) and a MFS family transporter (TU94_24835) are identified.Overexpression of nemR significantly increased nemadectin production by 79.9%,in comparison with NMWT1,suggesting that nemR plays an important role in the nemadectin biosynthesis.
Covalent organic frameworks derived hollow structured N-doped noble carbon for asymmetric-electrolyte Zn-air battery

We report a relatively low-temperature molten salt strategy to prepare hollow structured N-doped noble carbon(h-NNC)with highly desirable features of ultra-large surface area(1957 m~2 g~(–1))and high graphitization, endowing the h-NNC with high activity toward catalysis of oxygen reduction reaction in acidic medium. The h-NNC is applied as cathode catalyst of an asymmetrical-electrolyte Zn-air battery, which exhibits an open circuit voltage of 2.11 V, a power density up to 270 mW cm~(–2), and an energy density of 1279 W h kg~(–1), behaving advantages over the conventional Zn-air batteries.
Trimetallic Au@PdPt core-shell nanoparticles with ultrathin PdPt skin as highly stable electrocatalysts for the oxygen reduction reaction in acid solution

To design efficient and low-cost core-shell electrocatalysts with an ultrathin platinum shell, the balance between platinum dosage and durability in acid solution is of great importance. In the present work, trimetallic Au@PdPt core-shell nanoparticles(NPs)with Pd/Pt molar ratios ranging from 0.31:1 to 4.20:1 were synthesized based on the Au catalytic reduction strategy and the subsequent metallic replacement reaction. When the Pd/Pt molar ratio is 1.19:1(designated as Au@Pd_(1.19)Pt_1 NPs), the superior electrochemical activity and stability were achieved for oxygen reduction reaction(ORR)in acid solution. Especially, the specific and mass activities of Au@Pd_(1.19)Pt_1 NPs are 1.31 and 6.09 times higher than those of commercial Pt/C catalyst. In addition, the Au@Pd_(1.19)Pt_1 NPs presented a good durability in acid solution. After 3000 potential cycles between 0.1 and 0.7 V(vs. Ag/AgCl), the oxygen reduction activity is almost unchanged. This study provides a simple strategy to synthesize highperformance trimetallic ORR electrocatalyst for fuel cells.
扬子块体两侧造山带地壳推覆的地球物理证据及其地质意义

基于深部地球物理探测结果建立的青藏高原东缘-江南造山带的地壳结构,发现扬子块体在NW向受到来自青藏高原东缘物质的逆冲推覆,在SE向受到来自江南造山带物质的逆冲推覆.这些推覆作用控制了川西-江南雪峰造山带西部地壳构造.青藏高原向东挤出的物质,在龙门山断裂带附近遇到坚硬四川盆地的阻挡,以上、中地壳的向上逆冲推覆,下地壳插入到四川盆地之下和扬子块体内地壳的褶皱、缩短、增厚方式被吸收,形成熊坡、龙泉山构造带,造成浦江-成都-德阳断裂、龙泉山西坡断裂的NW向逆冲.这些结果回答了青藏高原东向挤出物质的去向问题.总之,扬子块体两侧受到造山带地壳逆冲推覆的发现,为研究华南地区的陆内造山机制,恢复构造演化历史和青藏高原侧向挤出的运动学过程开阔了视野.
塔里木盆地新元古代裂陷群结构构造及其形成动力学

塔里木盆地新元古界的构造属性及结构构造长期以来存在争议,也是深层研究的重点及难题.通过区域探井和地震资料联合解释,结合航磁资料综合研究发现,塔里木盆地深层存在近20个大小不等的南华纪-晚震旦世裂陷.裂陷发育在前寒武纪变质结晶基底上,与上覆显生宙盖层构造格局迥异.受正断层控制呈半地堑、不对称地堑及垒堑相间的构造样式,从东北到西南可分为NWW、NEE、NW向展布的三个裂陷群,地层最大厚度可达4100m.从南华纪到震旦纪主要断裂继承性活动,断陷沉降中心沿断裂向东迁移,震旦纪末期至早寒武世断裂活动减弱至停止.断裂走向及沉降中心展布表明,新元古代塔里木陆块不同部位分别处于NNE-SSW、NNW-SSE向拉张古应力场(相对现今),并伴有顺时针旋扭作用.根据同沉积断裂的活动性差异、岩浆活动、裂陷充填沉积物及与航磁异常的协调性分析,裂陷的构造属性多以大陆裂谷及陆内断陷为主.裂陷的主要发育期在0.8~0.61Ga,其形成与南阿尔金-西昆仑洋、南天山洋的初始打开为响应,且是Rodinia超大陆主要裂解期的产物.
万古霉素在42例金黄色葡萄球菌感染患者中的疗效及与其最低抑菌浓度分析

万古霉素是临床上治疗革兰阳性菌感染的一线经典老药。自二十世纪五十年代万古霉素上市以来,其在治疗金黄色葡萄球菌(Staphylococcus aureus, SAU)、凝固酶阴性葡萄球菌及肠球菌所致感染上始终占据重要地位。但临床上感染患者的增多、万古霉素的大量应用,也带来了一系列万古霉素对SAU的最低抑菌浓度(minimum inhibitory concentration, MIC)值升高、药物的敏感性下降、患者临床疗效欠佳的问题。至2012年9月,全球已发现33株万古霉素耐药的SAU。目前,临床上已有多例万古霉素对SAU的MIC升高相关文献报道;而根据2017版美国临床和实验室标准协会(Clinical and Laboratory Standards Institute,CLSI)指南,SAU对万古霉素的敏感界值定义为≤ 2,但临床上许多根据药敏结果应用万古霉素的患者,临床疗效确差强人意。除患者给药剂量不足、血药浓度不达标的影响之外,猜测万古霉素临床治疗效果与近年来SAU的MIC升高是否有一定的关系。为此,本研究对42例在治疗药物浓度监测下血药浓度达标、但细菌MIC不同的患者进行治疗效果的回顾性分析,探讨在SAU高MIC的情况下,应用万古霉素时患者的临床有效性。
隐丹参酮对顺铂化疗后荷瘤小鼠肝肾功能的保护作用

据2017年癌症统计报告:美国将有1 688 780例新增癌症病例及600 920例癌症死亡病例,而肺癌仍作为全球发病率及致死率最高的恶性肿瘤,超过1 / 4的癌症患者死于肺癌;晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)标准一线治疗仍为含铂类两药联合方案化疗。顺铂是周期非特异性抗肿瘤药物,长久以来作为重要的一线化疗药物应用于临床,但其不良反应包括肝肾功能损伤、骨髓抑制、胃肠道不适等严重限制了其在临床中的应用,给肿瘤患者带来了极大的伤害。前期研究显示,隐丹参酮对顺铂具有增效抗肿瘤细胞的作用,其机制与抑制Janus激酶/信号转导与转录激活子途径(janus kinase / signal transducer and activator of transcription,JAK / STAT)3信号通路相关,且在肺腺癌PC9、NCI-H1975细胞中进行了验证。本研究就隐丹参酮增效顺铂的体内试验进行初步探讨,且对隐丹参酮对顺铂导致的肝肾功能损伤的保护作用进行了研究,现报道如下。