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Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： Yun-Peng Li hao-ran Shen Shao-Juan Wang hao Zhang Jian Hu Rui Xin Xiao-Li Sun Shou-Ke Yan Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

Radical involved reactive wetting and retarding mechanism of alumina refractory ceramic by molten slags under weak static magnetic field

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Journal of Iron and Steel Research International 2024年第6期31卷 1355-1366页

作者： Sheng-hao Li Ao Huang Fan-bo Zeng Hui Peng hao-ran Wei Xue-chun Huang Sheng-qiang Song Hua-zhi Gu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory *** static magnetic field is a promising solution for improvement in the slag resistance of *** wetting of alumina refractory ceramics with different basicities of high alumina slags under a weak static magnetic field was analyzed,given that a weak static magnetic field can affect the corrosion behavior of refractory *** slag S_(3) as an example,when there was an external static magnetic field of 1.0 mT at 1600 ℃,the thickness of calcium aluminate reaction layer at the interface decreased by 36.7%,the denting depth of interface decreased by 35.6%,and the apparent wetting angle increased by 20%.The living radicals and their formation path in oxide melts were verified by first-principles calculation combined with electron paramagnetic resonance spectroscopy *** influence of the flux density of a weak static magnetic field on the wetting behavior of slags was also *** contact angle of the slags increased owing to the inhibitory effect of magnetic field on the radicalinvolved reaction at the interface of the slag and the alumina refractory *** relationships between the magnetic flux density,diffusion coefficient,slag microstructure(hyperfine coupling constant),and contact angle were *** provides a theoretical basis for the field control of radical involved reactive wetting between inorganic oxide slags and solid oxide ceramics.

关键词： Alumina refractory ceramic Molten slag Weak magnetic field effect Reactive wetting Free radical

Advancements in machine learning for material design and process optimization in the field of additive manufacturing

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China Foundry 2024年第2期21卷 101-115页

作者： hao-ran Zhou hao Yang Huai-qian Li Ying-chun Ma Sen Yu Jian shi Jing-chang Cheng Peng Gao Bo Yu Zhi-quan Miao Yan-peng Wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of Materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric ***,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high *** learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new *** paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process ***,it introduces the background and significance of machine learning-assisted design in additive manufacturing *** then further delves into the application of machine learning in additive manufacturing,focusing on model design and process ***,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

Electrochemical Cascade Annulation for the Synthesis of 3-Sulfanylquinoline Derivatives under Mild Conditions

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Chinese Journal of Chemistry 2024年第16期42卷 1833-1838页

作者： Ke Li Ming-Zhong Guo Zhuo Chen hao-ran Li Weisi Guo Ming Li Lin-Bao Zhang State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science&TechnologyQingdaoShandong 266042China

An efficient electrochemical approach has been developed for the construction of 3-sulfanylquinoline derivatives by treating phenylethynylbenzoxazinanones with disulfides in an undivided *** protocol provided a convenient route to functionalized quinolines with good functional group ***,it does not require any metal catalysts or additives,furnishing a series of biologicalquinolines inmoderatetogoodyields.

关键词： Electrocatalysis Electrooxidation Annulation 3-Sulfany quinoline C3-thioetherification

Enhancing thermoelectric performance of p-type SnTe through manipulating energy band structures and decreasing electronic thermal conductivity

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Rare Metals 2024年第7期43卷 3232-3241页

作者： Xin Qian hao-ran Guo Jia-Xin Lyu Bang-Fu Ding Xing-Yuan San Xiao Zhang Jiang-Long Wang Shu-Fang Wang Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China College of Electron and Information Engineering Hebei UniversityBaoding 071002China Research Institute for Frontier Science Beihang UniversityBeijing100191China

SnTe has received considerable attention as an environmentally friendly alternative to the representative thermoelectric material of ***,excessive hole carrier concentration in SnTe results in an extremely low Seebeck coefficient and high thermal conductivity,which makes it exhibit relatively inferior thermoelectric *** this work,the thermoelectric performance of p-type SnTe is enhanced through regulating its energy band structures and reducing its electronic thermal conductivity by combining Bi doping with CdSe ***,the carrier concentration of SnTe is successfully suppressed via Bi doping,which significantly decreases the electronic thermal ***,the convergence and flattening of the valence bands by alloying CdSe effectively improves the effective mass of SnTe while restraining its carrier ***,a maximum figure of merit(ZT) of~ 0.87 at 823 K and an average ZT of~ 0.51 at 300-823 K have been achieved in Sn_(0.96)Bi_(0.04)Te-5%*** results indicate that decreasing the electronic thermal conductivity is an effective means of improving the performance of thermoelectric materials with a high carrier concentration.

关键词： Thermoelectric materials SnTe Energy band structure Electronic thermal conductivity ZT value

Prospective life cycle assessment of CO2 conversion by photocatalytic reaction

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Knowledge Distillation via Hierarchical Matching for Small Object Detection

Green Chemical Engineering 2024年第3期5卷 383-389页

作者： Jun-Qi Wang Xiang-Jun Liu Jing-Jing Ma Shuai Zhang hao-ran Liu Yong-Li Dong Qing-Yuan Yang School of Human Settlements and Civil Engineering Xi'an Jiaotong University School of Chemical Engineering and Technology Xi'an Jiaotong University

CO2conversion is gradually seen as a better way for society to effectively use carbon sources and avoid climate crisis associated with fossil CO2emissions. And the decision to deploy CO2technology scale should be relied on its environmental impact. In this work, life cycle assessment model evaluates the environmental performance of CO2conversion by photocatalytic reaction process with two different catalysts（NiAl-LDH and Co-ZIF-9）. Six impact categories considered in this analysis, including climate change, acidification potential, depletion of abiotic resources, eutrophication potential, ozone layer depletion potential, and photochemical oxidation potential. Results indicated that CO2conversion with Co-ZIF-9 photocatalyst has a better environmental impact than the NiAl-LDH photocatalyst route. Moreover, the Co-ZIF-9 catalyst scenario also has a lower total environmental burden than the conventional CO production route. Sensitivity analysis shows that recycle performance of the catalyst is highly sensitive to the production process in two scenarios. This study could provide a framework for robust decisions in CO2conversion by photocatalytic reaction, which is useful for policymakers to decide the feasibility of industrialization.

关键词： Life cycle assessment (LCA) CO 2 Photocatalytic reaction Sensitivity analysis Uncertainty analysis

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Journal of Computer Science & Technology 2024年第4期39卷 798-810页

作者： Yong-Chi Ma Xiao Ma Tian-ran hao Li-Sha Cui Shao-Hui Jin Pei Lyu School of Computer Science and Artificial Intelligence Zhengzhou UniversityZhengzhou 450000China

Knowledge distillation is often used for model compression and has achieved a great breakthrough in image classification,but there still remains scope for improvement in object detection,especially for knowledge extraction of small *** main problem is the features of small objects are often polluted by background noise and not prominent due to down-sampling of convolutional neural network(CNN),resulting in the insufficient refinement of small object features during *** this paper,we propose Hierarchical Matching Knowledge Distillation Network(HMKD)that operates on the pyramid level P2 to pyramid level P4 of the feature pyramid network(FPN),aiming to intervene on small object features before *** employ an encoder-decoder network to encapsulate low-resolution,highly semantic information,akin to eliciting insights from profound strata within a teacher network,and then match the encapsulated information with high-resolution feature values of small objects from shallow layers as the *** this period,we use an attention mechanism to measure the relevance of the inquiry to the feature *** in the process of decoding,knowledge is distilled to the *** addition,we introduce a supplementary distillation module to mitigate the effects of background *** show that our method achieves excellent improvements for both one-stage and twostage object ***,applying the proposed method on Faster R-CNN achieves 41.7%mAP on COCO2017(ResNet50 as the backbone),which is 3.8%higher than that of the baseline.

关键词： knowledge distillation object detection small object detection machine learning

Higher palaeoelevation in the Baoshan Basin:Implications for landscape evolution at the southeastern margin of the Tibetan Plateau

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Journal of Palaeogeography 2024年第3期13卷 563-580页

作者： Yong-Jiang Huang hao-ran Zong Shi-Tao Zhang Arata Momohara Jin-Jin Hu Lin-Bo Jia Yun-Heng Ji Zhe-Kun Zhou Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201Yunnan ProvinceChina College of Forestry Shandong Agricultural UniversityTai'an 271018Shandong ProvinceChina Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093Yunnan ProvinceChina Graduate School of Horticulture Chiba UniversityChiba 271-8510Japan Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303Yunnan ProvinceChina

Surface uplift at the southeastern margin of the Tibetan Plateau has been widely studied,but more palaeoaltimetry data are required to better understand the elevation history of this geologically complex *** this study,fossil leaves of Abies(Pinaceae),a cool-temperate element,recovered from the latest Miocene-Pliocene Yangyi Formation of the southern Baoshan Basin,were used as a proxy to estimate the local *** on the regional modern altitude range(2100-4280 m)of the genus as well as regional temperature discrepancy(1.5℃)between the past and present,the palaeoelevation of the study area was calculated to be>2360 m above sea level as compared to 1670 m at *** result suggests that the southern Baoshan Basin experienced pronounced uplift prior to the time of fossil deposition,probably as a result of crustal shortening and thickening of the northern Baoshan Terrane during the *** infer that surface growth in areas south of the Dali Basin may have been greater than previously interpreted,and that a widespread plateau or plateau patches higher than 2000 m probably extended southwards into at least the Baoshan Basin by the latest *** also infer that the elevation of the southern Baoshan Basin has decreased by at least 690 m since then,in contrast to most other scenarios in which the elevation of the southeastern margin of the Tibetan Plateau has increased or remained close to modern levels since the late *** major cause of the inferred altitude decline is likely tectonic *** a transtensional graben basin,the Baoshan Basin has experienced pull-apart and base-fall movement since the late Miocene,which would reduce the altitude of its southern part located on the hanging *** erosion associated with the increased summer rainfall might also have played a role especially in reducing the local relief,although its contribution can be *** study provides one of the few palaeoelevation

关键词： Abies Lapse rate Palaeoaltimetry Surface uplift Tectonic movement Tibetan plateau

A mixed-valence polyoxometalate-based 3D inorganic framework cathode material for high-efficiency rechargeable AZIBs

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Rare Metals 2024年第8期43卷 3677-3691页

作者： Qing Han hao-ran Xiao Tao Zhou Bing-Chuan Li Liu Yang Ling-Ling Xie Xue-Jing Qiu Xian-Yong Wu Li-Min Zhu Xiao-Yu Cao School of Chemistry and Chemical Engineering Henan University of TechnologyZhengzhou 450001China Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou City Zhengzhou 450001China College of Materials Engineering Henan University of EngineeringZhengzhou450007China School of Environmental Engineering Henan University of TechnologyZhengzhou 450001China Department of Chemistry University of Puerto Rico-Rio Piedras CampusSan JuanPR 00925USA

The global trend towards new energy storage systems has stimulated the development of electrochemical energy storage *** these technologies,rechargeable aqueous zinc-ion batteries(AZIBs)have attracted considerable interest as a potential alternative to lithium-ion batteries(LIBs)due to their affordable cost,environmental compatibility and high safety *** this study,a high-quality electrode for AZIBs has been successfully developed using a dehydrated mixed-valence polyoxometalate-based three-dimensional(3D)inorganic framework material known as[H_6Mn_(3)V^Ⅳ_(15)V-^Ⅴ_(4O)_(46)(H_2O)_(12)](3D-MnVO).This innovative 3D-MnVO material is built from the alternate connections of{V_(19)O_(46)}"sphere-shaped"clusters andμ_(2)-{Mn(H_(2)O)_(4)}bridges,where each{V_(19)O_(46)}cluster is surrounded by three pairs of vertically distributed{Mn(H_(2)O)_(4)}units,thus resulting in the 3D interpenetrating grid-like network from the infinite[-{V_(19)O_(46)}-μ_(2)-Mn(H_(2)O)_(4)-{V_(19)O_(46)}]_∞chains in three mutually perpendicular *** 3D framework structure of 3D-MnVO possesses abundant oxygen vacancies,spacious and multi-level interconnected channels for ion transport,which facilitates the efficient intercalation/deintercalation of hydrated Zn^(2+)into the pores of the primary structure via the intercalation capacitance *** a result,the 3D-MnVO electrode exhibits excellent diffusion rates and minimal interfacial *** a current density of 0.1 A·g^(-1),the 3D-MnVO cathode delivers a commendable discharge capacity of170.5 mAh·g^(-1)with 81.6%capacity retention after100 charge/discharge ***,even at a high current density of 1.0 A·g^(-1),the 3D-MnVO electrode delivers a remarkable reversible capacity of198.9 mAh·g^(-1).Our research results provide valuable insights into the development of advanced polyoxometalate-based 3D inorganic framework electrode materials for high-performance rechargeable AZIBs.

关键词： Cathode Polyoxometalate 3D inorganic framework Zinc-ion batteries Energy storage mechanism