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Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

National Science Review 2024年第3期11卷 159-171页

作者： Rui wen Shao Jun Wei Wu Zheng Xing Wang Hui Xu Han qing Yang Qiang Cheng Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

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Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records

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Petroleum Science 2024年第2期21卷 1241-1256页

作者： Hui-wen Pang Han-qing Wang Yi-Tian Xiao Yan Jin Yun-Hu Lu Yong-Dong Fan Zhen Nie National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Science China University of Petroleum-BeijingBeijing102249China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China

Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network ***, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model.

关键词： Lost circulation Risk prediction Machine learning Seismic attributes Mud loss records

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The Crystallization Behavior of L-Poly(lactic acid)/Polypropylene Blends:The Acceleration for Both L-Poly(lactic acid)and Polypropylene

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Chinese Journal of Polymer Science 2024年第6期42卷 775-786页

作者： Shuang-Cheng Li Wei-Jia Zhou wen-Jie Wu Jun Shao Shui-Liang Chen Hao-qing Hou Sheng Xiang College of Chemistry&Chemical Engineering and Nanofiber Engineering Center of Jiangxi Province Jiangxi Normal UniversityNanchang330022China National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang330022China wenzhou Institute University of Chinese Academy of SciencesWenzhou325001China

For a polymer/polymer dismissible blend with two crystallizable components,the crystallization behavior of different components and the reciprocal influences between different crystals are interesting and important,but did not investigate in *** this study,the L-poly(lactic acid)/polypropylene(PLLA/PP)blends with different weight ratios were prepared by melt mixing and the crystallization behavior of the blends were *** showed that the crystalline structures of PLLA and PP were not altered by the *** the crystallization of PLLA,both the diffusion of chain segments and crystallization rate were enhanced under the existence of PP *** the crystallization of PP,its crystallization rate was depressed under the existence of amorphous PLLA molecular *** the PP crystallized from the existence of PLLA crystals,although the diffusion rate of PP was reduced by PLLA crystals,the nucleation positions were obviously enhanced,which accelerated the formation of PP *** investigation would supply more basic data for the application of PLLA/PP blend.

关键词： L-poly(lactic acid) Polypropylene Blends Crystalization behavior Crystallization acceleration

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Ultrasound diagnosis of congenital Morgagni hernias: Ten years of experience at two Chinese centers

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World Journal of Clinical Cases 2024年第3期12卷 495-502页

作者： Hui-qing Shi wen-Juan Chen Qiang Yin Xue-Hua Zhang Department of Ultrasound Fujian Children’s Hospital(Fujian Branch of Shanghai Children’s Medical Center)College of Clinical Medicine for Obstetrics&Gynecology and PediatricsFujian Medical UniversityFuzhou 350011Fujian ProvinceChina Department of Ultrasound Hunan Children’s HospitalUniversity of South ChinaChangsha 410007Hunan ProvinceChina Department of Pediatric Surgery Hunan Children’s HospitalUniversity of South ChinaChangsha 410007Hunan ProvinceChina

BACKGROUND Morgagni hernias are rare anomalies that are easily misdiagnosed or *** To summarize the ultrasound(US)imaging characteristics of Morgagni hernias through a comparison of imaging and surgical *** The records of children with Morgagni hernias who were hospitalized at two hospitals between January 2013 and November 2023 were retrospectively re-viewed in terms of clinical findings,US features,and operative *** Between 2013 and 2023,we observed nine(five male and four female)children with Morgagni *** abdominal scanning revealed a widening of the prehepatic space,with an abnormal channel extending from the xiphoid process to the right or left side of the thoracic *** channel had intestinal duct and intestinal gas *** contents were found in the transverse colon(n=6),the colon and small intestine(n=2),and the colon and stomach(n=1).Among the patients,seven had a right-sided lesion,two had a left-sided lesion,and all of them had hernial *** US imaging can accurately determine the location,extent,and content of Morgagni *** suspected Mor-gagni hernias,we recommend performing sonographic screening first.

关键词： Children Congenital diaphragmatic hernias Morgagni hernia Operation Ultrasound Gastrointestinal imaging

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Brønsted-acid sites induced photocatalytic cracking of low-polarity polyethylene plastics

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Journal of Energy Chemistry 2024年第9期96卷 509-515页

作者： Qianyou wen Quan Zhang Zhengzheng Liu Huining Wang Shuya Hao Fan Zhang Lijuan Zhang qing Han Gengfeng Zheng Laboratory of Advanced Materials Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

Polyolefins such as polyethylene(PE)are one of the largest-scale synthetic plastics and play a key role in modern ***,polyethylene is extremely inert to chemical recycling owing to its lack of chemical functionality and low polarity,making it one of the most challenging environmental hazards ***,we developed a phosphorylated CeO_(2)catalyst by an organophosphate precursor and featured efficient photocatalysis of low-density polyethylene(LDPE)without the acid or alkaline *** to pristine CeO_(2),the surface phosphorylation allows to introduce Brønsted acid sites,which facilitate to form carbonium ions on LDPE via *** addition,the suitable band structure of the phosphorylated CeO_(2)catalyst enables efficient photoabsorption and generates reactive oxygen species,leading to the C–C bond cleavage of *** a result,the phosphorylated CeO_(2)catalyst exhibited an outstanding carbon conversion rate of>94%after 48 h of photocatalysis under 50 mW/cm^(2)of simulated sunlight,with a high CO_(2)product selectivity of>99%.Furthermore,the PE microparticles with sizes larger than 10μm released from LDPE plastic wrap were directly and completely degraded by photocatalysis within 12 h,suggesting an attractive and environmentally benign strategy of utilizing solar energy-based photocatalysis for reducing potential hazards of LDPE plastic trashes.

关键词： Photocatalytic cracking Polyethylene Surface phosphorylation Bronsted-acid site Carbon conversion

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Cross-linked Electrospun Gel Polymer Electrolytes for Lithium-Ion Batteries

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Chinese Journal of Polymer Science 2024年第8期42卷 1021-1028页

作者： Xue Gong Qin Xiao qing-Yin Li wen-Cui Liang Feng Chen Long-Yu Li Shi-Jie Ren College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage ***,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical *** obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled Li/LiFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 *** results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for Lithium-ion battery applications that require high-temperature usage.

关键词： Electrospinning Cross-linked Gel polymer electrolytes Lithium-ion batteries

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Identification and effective regulation of scarb1 gene involved in pigmentation change in autotetraploid Carassius auratus

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Zoological Research 2024年第2期45卷 381-397页

作者： Xi-Dan Xu Yue Zhou Chong-qing Wang Xu Huang Kun Zhang Xiao-Wei Xu Li-wen he Xin-Yue Zhang Xin-Zhu Fu Ming Ma Qin-Bo Qin Shao-Jun Liu State Key Laboratory of Developmental Biology of Freshwater Fish Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education MinistryCollege of Life SciencesHunan Normal UniversityChangshaHunan 410081China Nansha-South China Agricultural University Fishery Research Institute GuangzhouGuangdong 511458China Hunan Yuelu Mountain Science and Technology Co.Ltd.for Aquatic Breeding ChangshaHunan 410081China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangshaHunan 410081China

The autotetraploid Carassius auratus(4nRR,4n=200,RRRR)is derived from whole-genome duplication of Carassius auratus red var.(RCC,2n=100,RR).In the current study,we demonstrated that chromatophores and pigment changes directly caused the coloration and variation of 4nRR skin(red in RCC,brownish-yellow in4nRR).To further explore the molecular mechanisms underlying coloration formation and variation in 4nRR,we performed transcriptome profiling and molecular functional verification in RCC and *** revealed that scarb1,associated with carotenoid metabolism,underwent significant down-regulation in *** editing of this candidate pigment gene provided clear evidence of its significant role in RCC ***,we identified four divergent scarb1 homeologs in 4nRR:two original scarb1 homeologs from RCC and two duplicated ***,three of these homeologs possessed two highly conserved alleles,exhibiting biased and allelespecific expression in the ***,after precise editing of both the original and duplicated scarb1homeologs and/or alleles,4nRR individuals,whether singly or multiply mutated,displayed a transition from brownishyellow skin to a cyan-gray ***,the proportional areas of the cyan-gray regions displayed a gene-dose *** findings illustrate the subfunctionalization of duplicated scarb1,with all scarb1genes synergistically and equally contributing to the pigmentation of *** is the first report concerning the functional differentiation of duplicated homeologs in an autopolyploidfish,substantiallyenrichingour understanding of coloration formation and change within this group of organisms.

关键词： Autopolyploidization Coloration change scarb1 Functional differentiation Genetic changes

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大方坯轴承钢中心偏析的成因及预防措施

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钢铁 2009年第8期44卷 39-41页

作者：何庆文王宝王福明刘青北京科技大学冶金与生态工程学院北京100083 莱芜钢铁股份有限公司特殊钢厂山东莱芜271105

对莱钢特钢厂连铸生产的大方坯轴承钢中心偏析的成因进行分析,研究了中间包钢水过热度等因素对中心偏析的影响,并对莱钢特钢厂的生产实践提出了预防措施。改善连铸轴承钢的中心偏析的方法和途径有:降低和稳定过热度,合理选择拉速、二冷... 详细信息

对莱钢特钢厂连铸生产的大方坯轴承钢中心偏析的成因进行分析,研究了中间包钢水过热度等因素对中心偏析的影响,并对莱钢特钢厂的生产实践提出了预防措施。改善连铸轴承钢的中心偏析的方法和途径有:降低和稳定过热度,合理选择拉速、二冷强度和电磁搅拌参数等。

关键词：轴承钢方坯中心偏析预防措施

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Mechanism research progress on transition metal compound electrode materials for supercapacitors

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Rare Metals 2024年第9期43卷 4076-4098页

作者： Zhi-Hui Xu Xue-Lei Li qing-wen Li Kai Lv Jing-Shun Liu Xiu-Kun Hang Aruuhan Bayaguud School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021China

Supercapacitors(SCs)have remarkable energy storage capabilities and have garnered considerable interest due to their superior power densities and ultra-long cycling ***,their comparatively low energy density limits their extensive application in large-scale commercial *** materials directly affect the performance of ***,the development of cutting-edge electrode materials and modification of their morphological and structural properties are vital for advancing the performance of *** metal compounds have a high specific capacity and good cycling durability,making them the most promising electrode active materials for high-energy density ***,their inadequate conductivity,unfavorable ion diffusion rates,substantial volume expansion and phase transitions during charging and discharging are obstacles to their stable and efficient integration into *** address these challenges,this study provides a comprehensive summary of the current advancements in transition metal nanomaterials as electrode materials for SCs,an overview of the current research status,and the prevailing ***,this study highlights synthetic techniques and management strategies for electrode materials derived from transition metal compounds,targeting the resolution of the aforementioned ***,a concise discussion is provided on the future directions of SC development,with an emphasis on the utilization of transition metal compound electrode materials.

关键词： Supercapacitors Transition metal compounds electrode Existing problems Synthetic methods Regulation strategies

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Enhanced direct gaseous CO_(2) fixation into higher bio-succinic acid production and selectivity

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Journal of Environmental Sciences 2024年第9期143卷 164-175页

作者： Ziyi Yang Wanling Wu qing Zhao Irini Angelidaki Samuel Gyebi Arhin Dongliang Hua Yuxiao Zhao Hangyu Sun Guangqing Liu wen Wang Biomass Energy and Environmental Engineering Research Center Beijing University of Chemical TechnologyBeijing 100029China College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Chemical and Biochemical Environmental Engineering Technical University of DenmarkDK-2800Kgs LyngbyDenmark Energy Research Institute Qilu University of Technology(Shandong Academy of Sciences)Shandong Provincial Key Laboratory of Biomass Gasification TechnologyJinan 250014China

Utilizing CO_(2)for bio-succinic acid production is an attractive approach to achieve carbon capture and recycling(CCR)with simultaneous production of a useful platform *** succinogenes and Basfia succiniciproducens were selected and investigated as microbial ***,the type and concentration of inorganic carbon concentration and glucose concentration were evaluated.6 g C/L MgCO_(3)and 24 g C/L glucose were found to be the optimal basic operational conditions,with succinic acid production and carbon yield of over 30 g/L and over 40%,***,for maximum gaseous CO_(2)fixation,carbonate was replaced with CO_(2)at different ***“less carbonate more CO_(2)”condition of the inorganic carbon source was set as carbonate:CO_(2)=1:9(based on the mass of carbon).This condition presented the highest availability of CO_(2)by well-balanced chemical reaction equilibrium and phase equilibrium,showing the best performance with regarding CO_(2)fixation(about 15 mg C/(L·hr)),with suppressed lactic acid *** to key enzymes analysis,the ratio of phosphoenolpyruvate carboxykinase to lactic dehydrogenase was enhanced at high ratios of gaseous CO_(2),which could promote glucose conversion through the succinic acid *** further increase gaseous CO_(2)fixation and succinic acid production and selectivity,stepwise CO_(2)addition was evaluated.50%-65%increase in inorganic carbon utilization was obtained coupled with 20%-30%increase in succinic acid *** was due to the promotion of the succinic acid branch of the glucose metabolism,while suppressing the pyruvate branch,along with the inhibition on the conversion from glucose to lactic acid.

关键词： Succinic acid CO_(2) fixation Actinobacillus succinogenes Basfia succiniciproducens Lactic acid

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