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Geoscience Frontiers 2024年第3期15卷 137-145页

作者： Kyle P.larson John m.Cottle mark Button Brendan Dyck Iva Lihter Sudip Shrestha Department of Earth Environmental and Geographic SciencesUniversity of British ColumbiaOkanaganKelownaCanada Department of Earth Science University of CaliforniaSanta BarbaraUSA Fipke Laboratory for Trace Element Research University of British ColumbiaOkanaganKelownaCanada

Re-examination of three specimens from the Kanchenjunga Himal of Nepal via in situ Lu-Hf garnet geochronology yields evidence of multiple garnet growth *** analyses from grain cores in two specimens define Paleozoic regressions whereas analyses from grain rims in the same specimens define low-precision regressions consistent with the timing of Himalayan *** dates contrast with previously published low dispersion,ca.290 ma isotope dissolution(ID)Lu-Hf garnet dates for the same *** of Lu and spot age distribution in representative grains from the specimens examined yields calculated dates that approximate the Permian-age regressions through the original ID *** findings demonstrate that it is possible to generate low dispersion ID Lu-Hf data from multigenerational garnet with significantly different-age growth events when approximately equal proportions of the different age reservoirs are included in multi-component aliquots.

关键词： Lu-Hf geochronology In situ Lu-Hf geochronology Kanchenjunga Himal

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美国页岩油气地质特征及勘探开发进展

石油勘探与开发 2024年第4期51卷 807-828页

作者： mCmAHON T P larson T E ZHANG T SHUSTER m 美国德克萨斯大学奥斯汀分校杰克逊地质科学学院经济地质局奥斯汀78758-4445德克萨斯州美国

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比... 详细信息

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比世)、早二叠世、晚侏罗世和晚白垩世(塞诺曼期—土伦期),构造沉积环境主要包括克拉通内盆地、前陆盆地和被动大陆边缘盆地。古生界富烃页岩主要分布于以下6个盆地:阿巴拉契亚盆地(尤蒂卡页岩和马塞勒斯页岩)、阿纳达科盆地(伍德福德页岩)、威利斯顿盆地(巴肯页岩)、阿卡马盆地(费耶特维尔页岩)、沃思堡盆地(巴内特页岩)和二叠盆地(狼营组和斯帕瑞组/骨泉组页岩)。中生界富烃页岩主要发育在西墨西哥湾盆地(海恩斯维尔组和鹰滩组)和落基山盆地群(以丹佛和粉河盆地的尼尔布拉勒组页岩为主)。通过对各页岩区带的详细分析发现,页岩的岩相和矿物成分存在差异,“页岩储层”并非只是页岩,很多情况下页岩油气还产自粉砂岩和碳酸盐岩等多种岩石类型。美国的页岩油气资源丰富,页岩油地质资源量超过0.246×1012 t,页岩气地质资源量超过290×1012 m3。在开启“页岩革命”的水平井水力压裂技术出现之前,美国经过了长达20年的勘探开发实践和理论技术积累。自2007年至2023年,美国页岩油气产量从约11.2×104t/d油当量增加到超过300.0×104t/d油当量,2017年页岩油气产量超过了常规油气,2023年在油气总产量中的占比增加到60%以上。页岩油气的开发主要得益于钻完井技术的改进,“立体开发”的攻关,以及重复压裂、提高原油采收率和“U”形井等技术的应用。基于美国丰富的页岩资源基础和技术的不断进步,页岩油气的产量将继续为全美的油气生产做出更大贡献。

关键词：美国页岩油页岩气页岩储层非常规储层油气产量资源评价

Spatio-temporal coupled mode theory for nonlocal metasurfaces

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Light(Science & Applications) 2024年第2期13卷 267-282页

作者： adam Overvig Sander A.mann Andrea Alù Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY10031USA Physics Program Graduate Center of the City University of New YorkNew YorkNY10016USA

Diffractive nonlocal metasurfaces have recently opened a broad range of exciting developments in nanophotonics research and applications,leveraging spatially extended—yet locally patterned—resonant modes to control light with new degrees of *** conventional grating responses are elegantly captured by temporal coupled mode theory,current approaches are not well equipped to capture the arbitrary spatial response observed in the nascent field of nonlocal ***,we introduce spatio-temporal coupled mode theory(STCmT),capable of elegantly capturing the key features of the resonant response of wavefront-shaping nonlocal *** framework can quantitatively guide nonlocal metasurface design while maintaining compatibility with local metasurface frameworks,making it a powerful tool to rationally design and optimize a broad class of ultrathin optical *** validate this STCmT framework against full-wave simulations of various nonlocal metasurfaces,demonstrating that this tool offers a powerful semi-analytical framework to understand and model the physics and functionality of these devices,without the need for computationally intense full-wave *** also discuss how this model may shed physical insights into nonlocal phenomena in photonics and the functionality of the resulting *** a relevant example,we showcase STCmT’s flexibility by applying it to study and rapidly prototype nonlocal metasurfaces that spatially shape thermal emission.

关键词： theory resonant spatially

Uplifting the complexity of analysis for probabilistic security of electricity supply assessments using artificial neural networks

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Energy and AI 2024年第3期17卷 313-326页

作者： Justin münch Jan Priesmann marius Reich marius Tillmanns Aaron Praktiknjo mario adam University of Applied Sciences Duesseldorf Centre of Innovative Energy SystemsMuensterstr.15640476 DuesseldorfGermany RWTH Aachen University E.ON Energy Research CenterChair for Energy System Economics(FCN-ESE)Mathieustrasse 1052074 AachenGermany

The energy sector faces rapid decarbonisation and decision-makers demand reliable assessments of the security of electricity supply. For this, detailed simulation models with a high temporal and technological resolution are required. When confronted with increasing weather-dependent renewable energy generation, probabilistic simulation models have proven. The significant computational costs of calculating a scenario, however, limit the complexity of further analysis. Advances in code optimization as well as the use of computing clusters still lead to runtimes of up to eight hours per scenario. However ongoing research highlights that tailor-made approximations are potentially the key factor in further reducing computing time. Consequently, current research aims to provide a method for the rapid prediction of widely varying scenarios. In this work artificial neural networks (ANN) are trained and compared to approximate the system behavior of the probabilistic simulation model. To do so, information needs to be sampled from the probabilistic simulation in an efficient way. Because only a limited space in the whole design space of the 16 independent variables is of interest, a classification is developed. Finally it required only around 35 min to create the regression models, including sampling the design space, simulating the training data and training the ANNs. The resulting ANNs are able to predict all scenarios within the validity range of the regression model with a coefficient of determination of over 0.9998 for independent test data (1.051.200 data points). They need only a few milliseconds to predict one scenario, enabling in-depth analysis in a brief period of time.

关键词： Security of electricity supply Probabilistic simulation metamodeling Artificial neural networks Regression

Non-symmetric differentially subordinate martingales and sharp weak-type bounds for Fourier multipliers

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Science China mathematics 2024年第8期67卷 1807-1826页

作者： meryem Akboudj Yong Jiao adam Osękowski School of mathematics and Statistics Hunan Key Laboratory of Analytical Mathematics and ApplicationsCentral South UniversityChangsha 410075China Faculty of mathematics Informatics and MechanicsUniversity of WarsawWarsaw 02-097Poland

Let p>2 be a given *** this paper,we prove,with the best constant,the weak-type(p,p)inequality■for a large class of non-symmetric Fourier multipliers T_(m) obtained via modulation of jumps of certain Lévy *** particular,the estimate holds for appropriate linear combinations of second-order Riesz transforms and skew versions of the Beurling-Ahlfors operator on the complex *** proof rests on a novel probabilistic bound for Hilbert-space-valued martingales satisfying a certain non-symmetric subordination *** applications to harmonic functions and Riesz systems on Euclidean domains are indicated.

关键词： weak-type bound Fourier multiplier martingale differential subordination laminate

Effective thermal conductivity estimation using a convolutional neural network and its application in topology optimization

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Energy and AI 2024年第1期15卷 236-247页

作者： Andre adam Huazhen Fang Xianglin Li Department of mechanical Engineering University of Kansas1530 W 15th St.Lawrence66045KSUSA Department of mechanical Engineering and materials Science Washington University in St.LouisOne Brookings DriveSt.Louis63130MOUSA

Topology optimization of heterogeneous structures can find significant use in a wide range of applications,and its fabrication has been made possible by recent advances in additive ***,the optimization procedure is computationally expensive,as each structural update requires the re-evaluation of the *** computational time is the major limiting factor in large-scale and complex structural *** this study,a convolutional neural network(CNN)model for predicting effective thermal conductivity inspired by the VGG networks is *** using 130,000 unique binary images,the model achieves high predictive ***,it shows a mean absolute percent error(mAPE)of 0.35%in testing when the thermal conductivity of the solid is ten times larger than the fluid,and when the thermal conductivities assigned are that of aluminum and water,the mAPE is 2.35%.The prediction time is 15 ms for a single image with 128×128 pixels,which is 3 to 5 orders of magnitude faster than a finite volume *** employed in topology optimization,the CNN retains a mAPE between 0.67%and 11.8%for different *** CNN model correctly predicts trends in effective thermal conductivity and improves the structure to close proximity of a theoretical maximum in all cases.

关键词： machine learning Effective thermal conductivity Convolutional neural network VGG Numerical heat transfer Topology optimization

The rate of deadwood decomposition processes in tree stand gaps resulting from bark beetle infestation spots in mountain forests

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Forest Ecosystems 2024年第3期11卷 339-346页

作者： Ewa Błonska adam Gorski Jarosław Lasota Department of Ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str.31-425KrakowPoland

Decaying wood is an essential element of forest ecosystems and it affects its other *** aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest *** research was carried out in the Babiog orski National *** research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle *** plots were located in undisturbed *** research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 *** samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was *** characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture *** decomposition of wood in the gaps regardless of the species is related to lower *** wood species covered by the study differed in the decomposition *** wood samples were characterized by a significantly higher decomposition rate compared to beech wood *** research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood.

关键词： Bark beetle Beech Decomposition rate Forest ecosystem mass decline Spruce Woody debris

Pioneering the direct large-scale laser printing of flexible“graphenic silicon”self-standing thin films as ultrahigh-performance lithium-ion battery anodes

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Carbon Energy 2024年第7期6卷 26-40页

作者： Avinash Kothuru adam Cohen Gil Daffan Yonatan Juhl Fernando Patolsky School of Chemistry Faculty of Exact SciencesTel Aviv UniversityTel AvivIsrael Department of materials Science and Engineering The Iby and Aladar Fleischman Faculty of EngineeringTel Aviv UniversityTel AvivIsrael

Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage ***-ion batteries(LIBs)have been the preferred choice for these applications,with graphite being the standard anode material due to its ***,graphite falls short of meeting the growing demand for higher energy density,possessing a theoretical capacity that lags *** address this,researchers are actively seeking alternative materials to replace graphite in commercial *** promising avenue involves lithiumalloying materials like silicon and phosphorus,which offer high theoretical ***-silicon composites have emerged as a viable option,showing improved capacity and performance over traditional graphite or pure silicon ***,the existing methods for synthesizing these composites remain complex,energy-intensive,and costly,preventing widespread adoption.A groundbreaking approach is presented here:the use of a laser writing strategy to rapidly transform common organic carbon precursors and silicon blends into efficient“graphenic silicon”composite thin *** films exhibit exceptional structural and energy storage *** resulting three-dimensional porous composite anodes showcase impressive attributes,including ultrahigh silicon content,remarkable cyclic stability(over 4500 cycles with∼40%retention),rapid charging rates(up to 10 A g^(-1)),substantial areal capacity(>5.1 mAh cm^(-2)),and excellent gravimetric capacity(>2400 mAh g^(-1) at 0.2 A g^(-1)).This strategy marks a significant step toward the scalable production of high-performance LIB *** widely available,cost-effective precursors,the laser-printed“graphenic silicon”composites demonstrate unparalleled performance,potentially streamlining anode production while maintaining exceptional *** innovation not only paves the way for advanced LIBs but also sets a precedent for

关键词： 4D printing energy storage fast-charging laser-induced graphene lithium-ion silicon carbon composite anodes

Community-led total sanitation(CLTS)implementation in West mamprusi municipal Assembly in *** do communities think eleven years on?

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Global Health Journal 2024年第2期8卷 67-73页

作者： Elijah adam Emmanuel Badu School of media Creative and Social InquiryCurtin UniversityBentleyWestern AustraliaAustralia School of Population Health Curtin UniversityBentleyWestern AustraliaAustralia

Objective Access to improved sanitation is a fundamental human right and an important aspect of Public ***,an estimated thousands of people in Ghana especially,the West mamprusi municipal Assembly(WmmA)still have no access to adequate toilet *** has brought untold health repercussions to the inhabitants,the community,and the environment at *** address this menace,the community-led total sanitation(CLTS)was *** study aimed to assess communities’perspectives on the implementation of CLTS and to understand the factors influencing its success and *** A mixed-method approach involving sequential qualitative and quantitative methods was employed in this *** for the quantitative study were randomly selected and surveyed using *** qualitative study employed focus group discussion involving purposively sampled participants including assembly members,opinion leaders,and assembly *** The CLTS program in WmmA realized an apparent use of construction and proper use of household latrines leading to a reduction of open defecation free(ODF)and two communities achieving sanitized status in the history of the study area,enabling the training of latrine artisans and natural leaders to facilitate the CLTS expansion and sustainability,improved sanitation and hygiene,strengthened the enforcement of community rules and regulations and many *** The CLTS program has received more widespread acceptance in the study area than the previous government policy of constructing public toilets,which was greeted with massive failures due to poor *** ensure that gains achieved through CLTS implementation are sustained longer,it is recommended that chiefs and opinion leaders should be involved in the CLTS programs to ensure checks and *** entrenchment of bylaws and more education to address enduring myths and misconceptions will sustain the *** in the form

关键词： Community-led total sanitation(CLTS) Community development Ghana Sanitation

‘Jelly to Joule’:Direct laser writing of sustainable jellyfish-based ‘graphenic silicon’ anodes for environmentally remediating high-performance lithium-ion batteries

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Journal of Energy Chemistry 2024年第10期97卷 553-565,I0012页

作者： Gil Daffan adam Cohen Yuval Sharaby Roman Nudelman Shachar Richter Fernando Patolsky Department of materials Science and Engineering the Iby and Aladar Fleischman Faculty of EngineeringTel Aviv UniversityTel Aviv 69978Israel school of Chemistry Faculty of Exact SciencesTel Aviv UniversityTel Aviv 69978Israel

The ramifications of global climate change and resource scarcities have made it imperative to re-examine the definition of sustainable energy-storage *** is crucial to recognize that not all renewable resources are inherently sustainable,and their full impact on the environment must be *** the proliferation of invasive jellyfish species wreaking havoc on marine ecosystems and economies worldwide,utilizing overabundant jellyfish as a carbon source presents an opportunity to create energy-storage systems that are both financially beneficial and environmentally ***,a comprehensive approach to sustainability also requires eco-friendly solutions throughout the entire lifecycle,from material sourcing to battery production,without compromising highperformance ***,most electrode syntheses for lithium-ion batteries(LIBs) employed are energy-intensive,multiple-steps,complex,and *** response,this work pioneers the straightforward use of low-energy laser irradiation of a jellyfish biomass/silicon nanoparticle blend to encapsulate the silicon nanoparticles in-situ within the as-forming conductive carbonized matrix,creating sustainable and additive-free composite *** self-standing anode is directly synthesized under ambient conditions and requires no ***,a laser-synthesized conductive threedimensional porous carbon/silicon composite anode from raw jellyfish biomass for LIBs is presented,displaying outstanding cyclic stability(>1000 cycles),excellent capacity retention(>50% retention after1000 cycles),exceptional coulombic efficiency(>99%),superb reversible gravimetric capacity(>2000 mAh/g),and high rate performance capability(>1.6 A/g),paving a new path to future sustainable energy production.

关键词： Laser Silicon Carbon Jellyfish Sustainable Lithium Biomass