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Ultrafast dynamics in layered materials:A new angle

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 201-201页

作者： hui zhao Department of Physics and Astronomy The University of KansasLawrence 66045USA

Layered materials have long captivated the scientific community due to their extraordinary structures and versatile optoelectronic properties[1].Time-resolved spectroscopic techniques based on femtosecond lasers have been widely used to reveal the ultrafast electronic and lattice dynamics,which play pivotal roles in high-speed and high-efficiency optoelectronic devices based on these ***,these studies have focused on the in-plane behaviors observed by measurements on the basal surfaces of such materials.

关键词： materials optoelectronic dynamics

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Integrating well logs, 3D seismic, and earthquake data for comprehensive prediction of 3D in-situ stress orientations: A case study from the Weiyuan area in the Sichuan Basin, China

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Petroleum Science 2025年第1期22卷 210-221页

作者： Huan Cao Yang zhao hai-Chao Chen Le-Le Zhang Cheng-Gang Xian Ji-Dong Yang Lu Liu State Key Laboratory of Petroleum Resources and Engineering and Unconventional Petroleum Research Institute China University of Petroleum (Beijing) Department of Geophysics China University of Petroleum (East China) Aramco Beijing Research Center Aramco Asia

Determining the orientation of in-situ stresses is crucial for various geoscience and engineering applications. Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(FMSs) derived from earthquake data and formation micro-imager(FMI) data from well ***, these techniques can be costly, depth-inaccurate, and may lack spatial coverage. To address this issue, we introduce the use of three-dimensional(3D) seismic data(active sources) as a lateral constraint to approximate the 3D stress orientation field. Recognizing that both stress and fracture patterns are closely related to seismic velocity anisotropy, we derive the orientation of azimuthal anisotropy from multi-azimuth 3D seismic data to compensate for the lack of spatial stress orientation information. We apply our proposed workflow to a case study in the Weiyuan area of the Sichuan Basin, China, a region targeted for shale gas production. By integrating diverse datasets, including 3D seismic, earthquakes, and well logs, we develop a comprehensive 3D model of in-situ stress(orientations and magnitudes). Our results demonstrate that the estimated anisotropy orientations from 3D seismic data are consistent with the direction of maximum horizontal principal stress(SHmax) obtained from FMIs. We analyzed 12earthquakes(magnitude > 3) recorded between 2016 and 2020 for their FMSs and compressional axis(Paxis) orientations. The derived SHmax direction from our 3D stress model is 110°ES(East-South), which shows excellent agreement with the FMSs(within 3.96°). This close alignment validates the reliability and precision of our integrated method for predicting 3D SHmax orientations.

关键词： In-situ stress orientation SHmax Azimuthal velocity anisotropy Focal source mechanism Formation micro-imager

Effect of graphene addition on activation and kinetic properties of La-Mg-Ni-based hydrogen storage alloys

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Journal of Iron and Steel Research International 2025年第1期32卷 227-238页

作者： Dian-chen Feng Chun-ling Zheng Zhi-yuan zhao Dong-sheng Zhou hui-ping Ren Yang-huan Zhang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Department of Functional Material Research China Iron and Steel Research Institute GroupBeijing100081China

The La_(1.7)Pr_(0.3)Mg_(16)Ni hydrogen storage alloy was prepared by medium-frequency induction melting,and then the composite hydrogen storage alloy powder of La_(1.7)Pr_(0.3)Mg_(16)Ni+x wt.%(x=0,2,4,and 6)graphene was prepared by ball milling for 10 *** effect of the addition of graphene on the activation and hydrogen de/absorption properties of La_(1.7)Pr_(0.3)Mg_(16)Ni alloy was *** result demonstrated that these composite alloys were composed of La_(2)Mg_(17),La_(2)Ni_(3),and Mg_(2)Ni *** saturated hydrogen absorption,it was composed of LaH_(3),Mg_(2)NiH_(4),and MgH_(2)phases,while during the dehydrogenation process,it was composed of LaH_(3),Mg,and Mg_(2)Ni *** addition of graphene can help get a more homogeneous granule after ball milling and accelerate the first activation of dehydrogenation/hydrogen *** hydrogen release activation energy of the alloys first decreases and then increases as the graphene content increases from x=0 wt.%to x=6 wt.%.The minimum activation energy of the composite hydrogen storage alloy is 51.22 kJ mol^(-1) when x=4 wt.%.

关键词： La-Mg-Ni alloy Graphene Mechanical ball milling Activation property Dynamic performance

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

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Tungsten 2025年第1期7卷 112-119页

作者： Jia-hui Li Qing zhao Dong-Ao Mao Kun Zhou Bao-Kuan Chen Yan-Feng Bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

关键词： Modular construction Photothermal conversion Polyoxometalate Thiacalixarene

Thermo-Hydraulic Performances of Microchannel Heat Sinks with Different Types of Perforated Rectangular Blocks

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Fluid Dynamics & Materials Processing 2025年第1期21卷 87-105页

作者： Heng zhao Honghua Ma hui Liu Xiang Yan Huaqing Yu Yongjun Xiao Xiao Xiao School of Physics and Electronic Information Engineering Hubei Engineering UniversityXiaogan432000China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China Institute of Engineering and Technology Hubei University of Science and TechnologyXianning437100China

The behavior of single-phase flow and conjugate heat transfer in micro-channel heat sinks(MCHS)subjected to auniform heat flux is investigated by means of numerical *** geometrical configurations areexamined,particularly,the combinations of rectangular solid and perforated blocks,used to create a disturbancein the *** analysis focuses on several key aspects and related metrics,including the temperature distribution,the mean Fanning friction factor,the pressure drop,the Nusselt number,and the overall heat transfer coefficientacross a range of Reynolds numbers(80–870).It is shown that the introduction of such blocks significantlyenhances the heat transfer performances of the MCHS compared to the straight-through flow ***,a case is found where the Nusselt number increases by 2.3 times relative to the reference *** integrationof perforated blocks facilitates the generation of vorticity within the channel,promoting the mixing of coldand hot ***,MCHS incorporating perforated rectangular blocks exhibit more pronounced heat transferbenefits at Reynolds numbers smaller than 400.

关键词： Micro-channel heat sink(MCHS) perforated rectangular blocks thermal performance convection heat transfer

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng zhao-Ying Ding Ying-Chao Li Yuan-Feng Wu Yuan-Yang Xu Rui Chen Xiao-Lei zhao hai-Yong Wang Da-Lei Zhang Yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

The Stereocomplex Crystallites Improve the Stability of Biodegradable Poly(L-lactic acid)/Poly(D-lactic acid)Melt-Blown Nonwovens

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Chinese Journal of Polymer Science 2025年第2期43卷 368-379页

作者： Jin-Shuo Yu Yue-Wei Huan Hong-Wei Pan Zhi-Gang Liu Yan zhao Zhi-Yong Tan Jun-Jia Bian hui-Li Yang hui-Liang Zhang Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun130022China College of Material and Engineering School of Chemical EngineeringEngineering Research Center of Synthetic Resin and Special FiberMinistry of EducationChangchun University of TechnologyChangchun130012China Shandong Fufeng Fermentation Co. Ltd.Shandong276600China National Engineering Research Center of Corn Deep Processing Jilin COFCO Biochemistry Co.Ltd.Changchun130033China

Poly(lactic acid)(PLA)is a biodegradable and eco-friendly polymer that is increasingly being incorporated into various applications in contemporary ***,the limited stability of PLA-based products remains a significant challenge for their broader use in various *** this study,poly(L-lactic acid)(PLLA)/poly(D-lactic acid)(PDLA)melt-blown nonwovens were prepared by melt *** structure,thermal properties,thermal stability,biodegradability and crystalline morphology of the melt-blown nonwovens were *** and WAXD confirmed the formation of stereocomplex(SC)crystallites in the PLLA *** storage modulus(G′),loss modulus(G″),and complex viscosity(∣η^(*)∣)of the PLLA/PDLA blend increased with an increase in SC crystallite *** thermal degradation temperatures of PLLA/PDLA melt-blown nonwovens increased with the incorporation of SC crystallites,and the maximum rate of decomposition increased to 385.5℃,thus enhancing the thermal *** with neat PLLA melt-blown nonwovens,the hydrophobicity of PLLA/PDLA melt-blown nonwovens was improved,and WCA increased to 139.7°.The SC crystallites were more resistant to degradation by proteinase K compared to neat ***,the degradation rate of PLLA/PDLA melt-blown nonwovens remained at a high *** work provides an effective strategy to obtain high-performance PLLA melt-blown nonwovens.

关键词： PLLA PDLA Melt-blown nonwovens Stereocomplex crystallites Thermal stability Enzymatic degradation

Cardiovascular response to nanosecond pulses is milder in percutaneous ablation of hepatocellular carcinoma compared with microsecond pulses

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Hepatobiliary & Pancreatic Diseases International 2025年第1期24卷 114-116页

作者： hai-Ying Kong Qian-hui Jin Xin-Hua Chen Dan-Xia Xu Qi-Yu zhao Xiong-Xin Zhang R James Swanson Tian-An Jiang Department of Anesthesiology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Division of Hepatobiliary Pancreatic Surgery Department of SurgeryThe First Hospital of JiaxingJiaxing University College of MedicineJiaxing 314000China Key Laboratory of Pulsed Power Translational Medicine of Zhejiang Province Hangzhou 310003China Department of Ultrasound Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Anatomy Department Liberty University College of Osteopathic MedicineLynchburgVAUSA

To the Editor:Irreversible electroporation(IRE)is a promising ablative technique for hepatobiliary *** has unique advantages,including no detrimental heat sink effect[1]and no injury of the surrounding tissues[2].For lesions in complex areas,bile duct[3],and large blood vessels[4],IRE has been developed as an alternative to thermal ablation such as radiofrequency and *** IRE tumor ablative technique combines cell biology and pulsed high-voltage *** high-voltage,high-frequency and transient pulses can create irreversible electroporation in the phospholipid bilayer of the cell membrane and nuclear envelope,resulting in cell *** with radiofrequency ablation and microwave ablation[5],IRE does not cause damage to important vessels and *** has some unique shortcomings in delivering high currents,which has limited its clinical applications in the *** animal and clinical studies,side effects including muscle contraction,procedural hypertension,and arrhythmia are frequently reported[6].However,during the ablation process,if the pulse is synchronized with the heart rhythm,the risk of arrhythmia is *** muscle relaxant eliminates muscle ***,arrhythmia[7],hypertension[8],and myocardial infarction[9]are potential risks requiring proper *** adverse events are mostly moderate and self-limiting,but they may have serious consequences for patients with coronary artery *** to the potential risks,patients with a history of cardiovascular disease are not recommended for IRE treatment.

关键词： microwave consequences ablation

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Rainfall impacts on nonpoint nitrogen and phosphorus dynamics in an agricultural river in subtropical montane reservoir region of southeast China

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Journal of Environmental Sciences 2025年第3期149卷 551-563页

作者： Yuanyi Wang hai Xu Xingchen zhao Lijuan Kang Yu Qiu Hans Paerl Guangwei Zhu huiyun Li Mengyuan Zhu Boqiang Qin Yunlin Zhang Mingliang Liu Key Laboratory of Lake and Watershed Science for Water Security Nanjing Institute of Geography&LimnologyChinese Academy of SciencesNanjing 210008China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Institute of Marine Sciences University of North Carolina at Chapel HillNC 28557USA Hangzhou Institute of Ecological and Environmental Sciences Hangzhou 310005China

The increased frequency and intensity of heavy rainfall events due to climate change could potentially influence the movement of nutrients from land-based regions into recipient ***,little information is available on how the rainfall affect nutrient dynamics in subtropicalmontane rivers with complex land *** study conducted high-frequency monitoring to study the effects of rainfall on nutrients dynamics in an agricultural river draining to Lake Qiandaohu,a montane reservoir of southeast *** results showed that riverine total nitrogen(TN)and total phosphorus(TP)concentrations increased continuously with increasing rainfall intensity,while TN:TP *** heavy rainfall and rainstorm drove more than 30%of the annual N and P loading in only 5.20%of the total rainfall period,indicating that increased storm runoff is likely to exacerbate eutrophication in montane ***_(3)^(−)-N is the primary nitrogen form lost,while particulate phosphorus(PP)dominated phosphorus *** source of N is cropland,and themain source of P is residential ***,forestedwatersheds have better drainage quality,while it is still a potential source of nonpoint pollution during rainfall *** and TP concentrations were significantly higher at sites dominated by cropland and residential area,indicating their substantial contributions to deteriorating river water ***,TN and TP concentrations reached high values in May-August when rainfall was most intense,while they were lower in autumn and winter than that in spring and summer under the same rainfall *** results emphasize the influence of rainfall-runoff and land use on dynamics of riverine N and P loads,providing guidance for nutrient load reduction planning for Lake Qiandaohu.

关键词： Non-point source pollution Rainfall events Land use type Mountain area Deepwater reservoir