A New Distribution Method for Wet Steam Injection Optimization

A new approach and a new related distribution system are proposed to address the issue of uneven steam injection caused by the different suction capacities of the used wells during the application of steam“stimulation”methods for enhanced oil recovery.The new distribution system consists of a swirler,spiral dividing baffles,and critical flow nozzles.Numerical simulations are used to analyze the flow-field and degree of steam homogeneity obtained with such an approach.The results indicate that a higher inlet pressure leads to better results.Additionally,the internal flow field becomes more stable,and the deviation from an even distribution reduces to±4.0%even when the resistance of each branch is inconsistent.Furthermore,field tests have yielded satisfactory results.

Characterization of the sphingolipid profiling of Emiliania huxleyi against virus infection

Lipidomics approach by UPLC-Q-Exactive-MS was used for the identification,quantification,comparison,and characterization of sphingolipids in virus infected marine Emiliania huxleyi BOF92 cells.The results show that 16 significantly changed sphingolipids(including Cer,CerG1,and SPHm)were identified during viral infection.Our data confirmed previously recognized facts that viral infection led to a shift toward virus-specific sphingolipids,which is consistent with the down-regulation of genes involved in the host de novo sphingolipid biosynthesis.Moreover,we revealed the upregulation of virusencoded homologous genes participating in de novo sphingolipids biosynthesis and virus-specific hydroxylated long chain bases(LCBs)as phytoCer,suggesting the competitive inhibition of host sphingolipid synthesis to produce the required building blocks for viral production,replication,and assembly.Additionally,Cer 40꞉1;2,Cer 40꞉2;2 isomer,and CerG139꞉0;2,Cer 39꞉0;2 as novel metabolite markers might indicate the general dysfunctions in E.huxleyi in response to viral infection.Our results show that viral infection led to a profound remodeling of host sphingolipidome,by which viruses depend on the hijacking of host sphingolipid metabolism to support the viral life cycle.

A peptide chain release factor 2a gene regulates maize kernel development by modulating mitochondrial function

Mitochondrial protein translation that is essential for aerobic energy production includes four essential steps of the mitochondrial ribosome cycle,namely,initiation,elongation,termination of the polypeptide,and ribosome recycling.Translation termination initiates when a stop codon enters the A site of the mitochondrial ribosome where it is recognized by a dedicated peptide release factor(RF).However,RFs and mechanisms involved in translation in plant mitochondria,especially in monocotyledons,remain largely unknown.Here,we identified a crumpled kernel(crk5 allele)mutant,with significantly decreased kernel size,100-kernel weight,and an embryo-lethal phenotype.The Crk5 allele was isolated using map-based cloning and found to encode a mitochondrial localization RF2a.As it is an ortholog of Arabidopsis mitochondrial RF2a,we named the gene ZmmtRF2a.ZmmtRF2a is missing the 5th–7th exons in the crk5 resulting in deletion of domains containing motifs GGQ and SPF that are essential for release activity of RF,mitochondrial ribosome binding,and stop codon recognition.Western blot and qRT-PCR analyses indicate that the crk5 mutation results in abnormal mitochondrion structure and function.Intriguingly,we observed a feedback loop in the crk5 with up-regulated transcript levels detected for several mitochondrial ribosome and mitochondrial-related components,in particular mitochondrial complexes CI,CIV,and a ribosome assembly related PPR.Together,our data support a crucial role for ZmmtRF2a in regulation of mitochondrial structure and function in maize.

Experimental Analysis of the Flow Characteristics of an Adjustable Critical-Flow Venturi Nozzle

The response of an adjustable critical-flow Venturi nozzle is investigated through a set indoor experiments aimed to determine the related critical flow rate,critical pressure ratio,and discharge coefficient.The effect of a variation in the cone displacement and liquid content on the critical flow characteristics is examined in detail and it is shown that the former can be used to effectively adjust the critical flow rate.The critical pressure ratio of the considered nozzle is above 0.85,and the critical flow control deviation of the gas flow is within±3%.Liquid flow can reduce the gas critical mass flow rate accordingly,especially for the cases with larger liquid volume and lower inlet pressure.The set of results and conclusions provided are intended to support the optimization of steam injection techniques in the context of heavy oil recovery processes.

Early diagenesis of redox-sensitive trace metals in the northern Okinawa Trough

The early diagenesis processes of several redox-sensitive trace metals(RSMs)(Mo, U and V) were studied with several short sediment cores(~25 cm) collected in the northern Okinawa Trough(OT). Pore water vertical profiles indicated that the sedimentary environments in all cores were between oxic and suboxic, not yet reaching anoxic sulfidic conditions. The recycling process of Mo in sediments was clearly associated with Mn and yielded little authigenic accumulation, while U showed a downcore increase in sediment and its authigenic mass accumulation rate(MAR) was estimated to be ~23% of the Changjiang(Yangtze) and Huanghe(Yellow) riverine flux. Benthic diffusive fluxes and MAR were calculated and the comparison of them showed that U and V fluxes matched relatively well both in direction and in magnitude, implying that diffusion processes at the sedimentwater interface is the dominant process controlling the remobilization or burial of V and U in northern OT. This work provided a systematic study(both in pore water and solid phase) on the RSMs geochemical behaviors during early diagenesis process, yielding a quantitative assessment of the remobilization or burial fluxes of the RSMs in northern OT. Such studies are in general lacking in the coastal margin of Northwest Pacific Ocean.

Coexistence of Quasi-two-dimensional Superconductivity and Tunable Kondo Lattice in a van der Waals Superconductor

Realization of Kondo lattice in superconducting van der Waals materials not only provides a unique opportunity for tuning the Kondo lattice behavior by electrical gating or intercalation,but also is helpful for further understanding the heavy fermion superconductivity.Here we report a low-temperature and vector-magneticfield scanning tunneling microscopy and spectroscopy study on a superconducting compound(4Hb-TaS_(2))with alternate stacking of 1T-TaS_(2)and 1H-TaS_(2)layers.We observe the quasi-two-dimensional superconductivity in the 1H-TaS_(2)layer with anisotropic response to the in-plane and out-of-plane magnetic fields.In the 1T-TaS_(2)layer,we detect the Kondo resonance peak that results from the Kondo screening of the unpaired electrons in the Star-of-David clusters.We also find that the intensity of the Kondo resonance peak is sensitive to its relative position with the Fermi level,and it can be significantly enhanced when it is further shifted towards the Fermi level by evaporating Pb atoms onto the 1T-TaS_(2)surface.Our results not only are important for fully understanding the electronic properties of 4Hb-TaS_(2),but also pave the way for creating tunable Kondo lattice in the superconducting van der Waals materials.

Seeing through dynamics scattering media:Suppressing diffused reflection based on decorrelation time difference

We observed a phenomenon that different scattering components have different decorrelation time.Based on decorrelation time difference,we proposed a method to image an object hidden behind a turbid medium in a reflection mode.In order to suppress the big disturbance calused by reflection and back scattering,two framnes of speckles are recorded in sequence,and their difference is used for image reconstruction.Our method is immune to both medium motions and object movements.

Copper and zinc isotope variations in ferromanganese crusts and their isotopic fractionation mechanism

Ferromanganese(Fe-Mn)crusts are potential archives of the Cu and Zn isotope compositions of seawater through time.In this study,the Cu and Zn isotopes of the top surface of 28 Fe-Mn crusts and 2 Fe-Mn nodules were analysed by MC-ICP-MS using combined sample-standard bracketing for mass bias correction.The Zn isotope compositions of the top surface of Fe-Mn crusts are in the range of 0.71‰to 1.08‰,with a mean δ^(66)Zn value of 0.94‰±0.21‰(2 SD,n=28).The δ^(65)Cu values of the top surface of Fe-Mn crusts range from 0.33‰to0.73‰,with a mean value of 0.58‰±0.20‰(2 SD,n=28).The Cu isotope compositions of Fe-Mn crusts are isotopically lighter than that of dissolved Cu in deep seawater(0.58‰vs.0.9‰).In contrast,the δ^(66)Zn values of Fe-Mn crusts appear to be isotopically heavy compared to deep seawater(0.94‰±0.21‰vs.0.51‰±0.14‰).The isotope fractionation between Fe-Mn crusts and seawater is attributed to equilibrium partitioning between the sorption to crusts and the organic-ligand-bound Cu and Zn in seawater.The Cu and Zn isotopes in the top surface of Fe-Mn crusts are not a direct reflection of the Cu and Zn isotopes,but a function of Cu and Zn isotopes in modern seawater.This study proposes that Fe-Mn crusts have the potential to be archives for paleoceanography through Cu and Zn isotope analysis.

受活字印刷启发的可用于信息存储的自愈合荧光液晶弹性体

信息存储材料的发展在信息社会的进步中起着关键作用.然而,在光寻址记录信息时,通常每次记录信息都需要更换不同的掩模,这在实际应用中极为不便.本文受活字印刷术的启发,开发了一种可作为信息存储和记录介质的自愈合荧光液晶弹性体.该薄膜在温和的加热条件下经由简单的两阶段胺-丙烯酸酯aza-Michael反应制备而成.由于α-氰基取代二芳基乙烯荧光分子的光异构化,液晶弹性体薄膜表现出光可调的荧光特性.同时,动态硼酸酯键的引入使其具备了优异的自愈合和可重构形状性能.以上述荧光液晶弹性体薄膜作为存储介质,概念验证性地展示了活字印刷驱动的信息记录,该方法避免了重复更换光掩膜,并延长了存储材料的使用寿命.这项工作为开发易于使用的、可大面积制备的信息存储材料提供了有益的启示.

Progress in non-viral localized delivery of siRNA therapeutics for pulmonary diseases

Emerging therapies based on localized delivery of siRNA to lungs have opened up exciting possibilities for treatment of different lung diseases.Localized delivery of siRNA to lungs has shown to result in severalfold higher lung accumulation than systemic route,while minimizing non-specific distribution in other organs.However,to date,only 2 clinical trials have explored localized delivery of siRNA for pulmonary diseases.Here we systematically reviewed recent advances in the field of pulmonary delivery of siRNA using non-viral approaches.We firstly introduce the routes of local administration and analyze the anatomical and physiological barriers towards effective local delivery of siRNA in lungs.We then discuss current progress in pulmonary delivery of siRNA for respiratory tract infections,chronic obstructive pulmonary diseases,acute lung injury,and lung cancer,list outstanding questions,and highlight directions for future research.We expect this review to provide a comprehensive understanding of current advances in pulmonary delivery of siRNA.

Changes in Persistent Precipitation in Northwest China and Related Large-Scale Circulation Features

Based on China's daily precipitation data of 2415 stations and ERA5 hourly reanalysis data from 1961 to 2019, the station-based and regional precipitation events over Northwest China(NWC) are identified and sorted into persistent precipitation(PP, duration ≥ 2 days) events and non-persistent precipitation(NPP, duration = 1 day) events;and then changes in the persistence structure of the PP and NPP events over NWC and the long-term mean adjustment of the related large-scale circulation configuration are analyzed. The results show that PP and NPP both witness an increasing trend over most parts of NWC. In terms of the total precipitation at most stations and the regional mean, contributions from PP have been increasing, while those from NPP have been decreasing. This demonstrates that the wetting trend in NWC is mainly caused by the increase in PP. Through analyzing the large-scale circulation corresponding to regional PP events at several representative levels, we found that the westerly jet at 200 hPa, the ridge/trough systems at 500 hPa, and the Mongolian low at sea level are the key circulation systems responsible for regional PP events over NWC. As for long-term mean changes after and before 1990(a shifting point recognized by previous studies), it is found that the extent of the South Asian high becomes larger and the westerly jet shifts northward by approximately 1.5 degrees in the upper troposphere. The ridge near the Ural Mountains and the ridge downstream of NWC strengthen by approximately 10–30 hPa at 500 hPa. Furthermore, the difference between the Mongolian low trough and its surrounding high pressure increases by approximately 2 hPa at the sea level. The combinations of circulation changes from upper to lower levels facilitate the strengthening of ascending motions. These adjustments in circulations create more favorable conditions for PP to occur over NWC in the last three decades.

Physical origin and boundary of scalable imaging through scattering media:a deep learning-based exploration

Imaging through scattering media is valuable for many areas,such as biomedicine and communication.Recent progress enabled by deep learning(DL)has shown superiority especially in the model generalization.However,there is a lack of research to physically reveal the origin or define the boundary for such model scalability,which is important for utilizing DL approaches for scalable imaging despite scattering with high confidence.In this paper,we find the amount of the ballistic light component in the output field is the prerequisite for endowing a DL model with generalization capability by using a“one-to-all”training strategy,which offers a physical meaning invariance among the multisource data.The findings are supported by both experimental and simulated tests in which the roles of scattered and ballistic components are revealed in contributing to the origin and physical boundary of the model scalability.Experimentally,the generalization performance of the network is enhanced by increasing the portion of ballistic photons in detection.The mechanism understanding and practical guidance by our research are beneficial for developing DL methods for descattering with high adaptivity.

Alternative Interpretation of Speckle Autocorrelation Imaging Through Scattering Media

High-resolution optical imaging through or within thick scattering media is a long sought after yet unreached goal.In the past decade,the thriving technique developments in wavefront measurement and manipulation do not significantly push the boundary forward.The optical diffusion limit is still a ceiling.In this work,we propose that a scattering medium can be conceptualized as an assembly of randomly packed pinhole cameras and the corresponding speckle pattern as a superposition of randomly shifted pinhole images.The concept is demonstrated through both simulation and experiments,confirming the new perspective to interpret the mechanism of information transmission through scattering media under incoherent illumination.We also analyze the efficiency of single-pinhole and dual-pinhole channels.While in infancy,the proposed method reveals a new perspective to understand imaging and information transmission through scattering media.

Modulation of electronic state in copper-intercalated 1T-TaS_(2)

Intercalation is an effective method to modify physical properties and induce novel electronic states of transition metal dichalcogenide(TMD)materials.However,it is difficult to reveal the microscopic electronic state evolution in the intercalated TMDs.Here we successfully synthesize the copper-intercalated 1T-TaS_(2) and characterize the structural and electronic modification combining resistivity measurements,atomic-resolution scanning transmission electron microscopy(ADF-STEM),and scanning tunneling microscopy(STM).The intercalated Cu atom is determined to be directly below the Ta atom and suppresses the commensurate charge density wave(CCDW)phase.Two specific electronic modulations are discovered in the near-commensurate(NC)CDW phase:the electron doping state near the defective star of Davids(SDs)in metallic domains and the spatial evolution of the Mott gap in insulating domains.Both modulations reveal that intercalated Cu atoms act as a medium to enhance the interaction between intralayer SDs,in addition to the general charge transfer effect.It also solidifies the Mott foundation of the insulating gap in pristine samples.The intriguing electronic evolution in Cu-intercalated 1T-TaS_(2) will motivate further exploration of novel electronic states in the intercalated TMD materials.