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New construction of mutually unbiased bases for odd-dimensional state space
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作者 王成红 王昆 郑驻军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期180-184,共5页
We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We ... We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We then provide a method for selecting mutually unbiased vectors from the eigenvectors of generalized Pauli matrices to construct mutually unbiased bases.In particular,we present four mutually unbiased bases in C^(15). 展开更多
关键词 mutually unbiased bases Hilbert space Pauli matrix quantum measurement
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Research on the Construction and Development of Aesthetic Education Bases in Higher Education Institutions
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作者 Wei Zhou 《Journal of Contemporary Educational Research》 2024年第10期48-53,共6页
In order to implement the national aesthetic education policy,it is essential to organically integrate relevant aesthetic education resources,promote interdisciplinary education,and carry out extracurricular practical... In order to implement the national aesthetic education policy,it is essential to organically integrate relevant aesthetic education resources,promote interdisciplinary education,and carry out extracurricular practical activities centered on aesthetic education.Strengthening the foundation of aesthetic education theory,addressing practical challenges in the teaching process,and closely linking research with teaching will create a feedback loop that benefits drama education.This article provides an in-depth analysis of the construction strategies,resource advantages and disadvantages,and development of aesthetic education bases,offering countermeasures and suggestions for their construction in universities.It aims to provide a solid research foundation for the growth and development of aesthetic education bases in higher education institutions. 展开更多
关键词 Aesthetic education Educational base Construction and development
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Homogenization Construction of Three-Level Teaching Bases for General Practice Medicine Under the Internet+Model
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作者 Yu Cai Ge Wu +3 位作者 Yuanyuan Jia Siqi Wang Chang Tian Yu Feng 《Journal of Contemporary Educational Research》 2024年第5期46-52,共7页
With the continuous expansion of medical student enrollment,the number of clinical teaching bases is gradually increasing.However,there are significant differences in clinical teaching management models and teaching l... With the continuous expansion of medical student enrollment,the number of clinical teaching bases is gradually increasing.However,there are significant differences in clinical teaching management models and teaching levels among different bases.Most clinical teaching bases have incomplete teaching management systems,inadequate teaching management institutions,insufficient teaching personnel,and inadequate implementation of teaching rules and regulations.This article combines the construction practice of three-level clinical teaching base of the General Medicine College and the First Affiliated Hospital of Xi’an Medical University.We establish a standardized management system for the three-level clinical teaching base;implement a teaching supervision system and strengthen the monitoring of teaching quality;adopt multiple evaluations to test the effectiveness of clinical teaching implementation;explore the path of homogenization construction of teaching bases in terms of unified teacher training,promoting the development of teacher teaching abilities with equal quality and excellence,and providing a reference for improving the quality of medical talent training. 展开更多
关键词 Clinical teaching base Homogenization construction General practice medicine
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Physiological and molecular bases of the boron deficiency response in tomatoes
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作者 Junjun Li Huihui Fan +8 位作者 Qianqian Song Lili Jing Hao Yu Ruishan Li Ping Zhang Fei Liu Weimin Li Liangliang Sun Jin Xu 《Horticulture Research》 SCIE CSCD 2023年第12期26-44,共19页
Boron is an essential microelement for plant growth.Tomato is one of the most cultivated fruits and vegetables in the world,and boron deficiency severely inhibits its yield and quality.However,the mechanism of tomato ... Boron is an essential microelement for plant growth.Tomato is one of the most cultivated fruits and vegetables in the world,and boron deficiency severely inhibits its yield and quality.However,the mechanism of tomato in response to boron deficiency remains largely unclear.Here,we investigated the physiological and molecular bases of the boron deficiency response in hydroponically grown tomato seedlings.Boron deficiency repressed the expression of genes associated with nitrogen metabolism,while it induced the expression of genes related to the pentose phosphate pathway,thereby altering carbon flow to provide energy for plants to cope with stress.Boron deficiency increased the accumulation of copper,manganese and iron,thereby maintaining chlorophyll content and photosynthetic efficiency at the early stage of stress.In addition,boron deficiency downregulated the expression of genes involved in cell wall organization and reduced the contents of pectin and cellulose in roots,ultimately retarding root growth.Furthermore,boron deficiency markedly altered phytohormone levels and signaling pathways in roots.The contents of jasmonic acid,jasmonoy1-L-isoleucine,trans-zeatin riboside,abscisic acid,salicylic acid,and SA glucoside were decreased;in contrast,the contents of isopentenyladenine riboside and ethylene precursor 1-aminocyclopropane-1-carboxylic acid were increased in the roots of boron-deficient tomato plants.These results collectively indicate that tomato roots reprogram carbon/nitrogen metabolism,alter cell wall components and modulate phytohormone pathways to survive boron deficiency.This study provides a theoretical basis for further elucidating the adaptive mechanism of tomato in response to boron deficiency. 展开更多
关键词 BORON bases thereby
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Imaging characteristics and treatment strategies for carotid artery occlusion caused by skull base fracture:Three case reports 被引量:1
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作者 Pei-Xin Shangguan Ke-Chun Zhou 《World Journal of Clinical Cases》 SCIE 2024年第15期2664-2671,共8页
BACKGROUND Traumatic internal carotid artery(ICA)occlusion is a rare complication of skull base fractures,characterized by high mortality and disability rates,and poor prognosis.Therefore,timely discovery and correct ... BACKGROUND Traumatic internal carotid artery(ICA)occlusion is a rare complication of skull base fractures,characterized by high mortality and disability rates,and poor prognosis.Therefore,timely discovery and correct management are crucial for saving the lives of such patients and improving their prognosis.This article retrospectively analyzed the imaging and clinical data of three patients,to explore the imaging characteristics and treatment strategies for carotid artery occlusion,combined with severe skull base fractures.CASE SUMMARY This case included three patients,all male,aged 21,63,and 16 years.They underwent plain film skull computed tomography(CT)examination at the onset of their illnesses,which revealed fractures at the bases of their skulls.Ultimately,these cases were definitively diagnosed through CT angiography(CTA)examinations.The first patient did not receive surgical treatment,only anticoagulation therapy,and recovered smoothly with no residual limb dysfunction(Case 1).The other two patients both developed intracranial hypertension and underwent decompressive craniectomy.One of these patients had high intracranial pressure and significant brain swelling postoperatively,leading the family to choose to take him home(Case 2).The other patient also underwent decompressive craniectomy and recovered well postoperatively with only mild limb motor dysfunction(Case 3).We retrieved literature from PubMed on skull base fractures causing ICA occlusion to determine the imaging characteristics and treatment strategies for this type of disease.CONCLUSION For patients with cranial trauma combined with skull base fractures,it is essential to complete a CTA examination as soon as possible,to screen for blunt cerebrovascular injury. 展开更多
关键词 Skull base fracture Traumatic internal carotid artery occlusion Blunt cerebrovascular injury Imaging Case report
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Discussion on Construction and Mechanism of Practice Bases for Professional Degree Postgraduates Based on the Integration of Production and Education in Local Universities
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作者 Dabing XIANG Yu FAN +5 位作者 Xueling YE Changying LIU Liangzhen JIANG Yan WAN Yuehua WANG Yanxia SUN 《Agricultural Biotechnology》 CAS 2023年第5期75-77,87,共4页
Under the background of emerging agricultural education,practice bases are an important place to train profession talented person that match social needs,so it is very important to build stable and long-term practice ... Under the background of emerging agricultural education,practice bases are an important place to train profession talented person that match social needs,so it is very important to build stable and long-term practice bases.At present,the main problems in the construction of practice bases for postgraduates in local colleges and universities are mainly focusing on construction and neglecting management,imperfect cooperation mechanism and lack of teaching management effectively.It is of great significance to build a long-term management mechanism to ensure the education quality of practice bases.Therefore,constructing the mode of"double integration and double promotion of production and education"with practice bases as the carrier and realizing the organic combination of industrial needs and postgraduate projects is an important idea for local colleges and universities to train professional degree postgraduates to"know agriculture,love agriculture,strengthen agriculture and promote agriculture",and it also provides a reference for the mechanism construction of postgraduate bases. 展开更多
关键词 Emerging Agricultural Education Professional master Integration of science and education Practice base MECHANISM
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Synthesis, Characterization and Biological Activity Evaluation of Schiff Bases Derived from 1,8-Diaminonaphtalène
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作者 Niameke Jean Baptiste Kangah Nanou Tiéba Tuo +4 位作者 Daouda Ballo Ahmont Landry Claude Kablan N’goran Etienne Kouame Charles Guillaume Kodjo Nahossé Ziao 《Open Journal of Physical Chemistry》 CAS 2023年第2期29-37,共9页
The compounds have been synthesized and characterized by routine MS, IR and NMR spectrometry methods. The compounds are all active on bacterial strains with the exception of Salmonella typhimirium, with a MIC value of... The compounds have been synthesized and characterized by routine MS, IR and NMR spectrometry methods. The compounds are all active on bacterial strains with the exception of Salmonella typhimirium, with a MIC value of 7.5 mg/mL. They show a percentage of anti-radical activity of 75.476 ± 5.070 for the compound DAN-S and of 68.142 ± 6.539 for the compound DAN-OV. The compounds are sensitive to the two champions used. DAN-S compound is then the most active. 展开更多
关键词 Schiff base SPECTROMETRY ANTIOXIDANT Antimicrobial Activity INHIBITION 1 8-Diaminonaphthalene
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Solving the k-Independent Sets Problem of Graphs by Gröbner Bases
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作者 Junyu Luo Shengzhen Ding 《Open Journal of Discrete Mathematics》 2023年第3期86-94,共9页
The aim of this paper is to given an algebraic computational method for finding maximal independent sets as well as the independent number of an arbitrary finite graph of n vertices G by strengthening the problem of f... The aim of this paper is to given an algebraic computational method for finding maximal independent sets as well as the independent number of an arbitrary finite graph of n vertices G by strengthening the problem of finding maximal independent sets of G to the problem of finding k-independent sets in G for. It is shown that the existence of k-independent sets in G is equivalent to the existence of solutions of a system of multivariate polynomial equations. It follows that the problem of finding k-independent sets can be realized by using Gröbner bases of polynomial ideals. Since the number of k-independent sets is finite, the triangular equations composed by Gröbner bases are easier to be solved. Consequently, the maximal independent sets and the independent number of G are obtained after solving at most n such equations. Finally, the numerical example is presented to illustrate the effectiveness of this algebraic computational method. 展开更多
关键词 k-Independent Set Maximal Independent Set Gröbner bases
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Novel Mannich Bases of Benzimidazole Derivatives: An Antibacterial Study of Environmental Bacterial Strains
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作者 Evrard Ablo Ouehi Dosso +6 位作者 Bakary Coulibaly Kouassi Franscesco Adingra Penayori Marie-Aimée Coulibaly Armand Patrick Achi Tchambaga Etienne Camara Souleymane Coulibaly Siomenan Coulibali 《Advances in Biological Chemistry》 2023年第5期182-191,共10页
A previous study was conducted on the synthesis and antibacterial evaluation of Mannich bases of 2-(thioalkyl)-1H-methylbenzimidazole derivatives. The results of this study showed that certain 2-(thioalkyl)-1H-methylb... A previous study was conducted on the synthesis and antibacterial evaluation of Mannich bases of 2-(thioalkyl)-1H-methylbenzimidazole derivatives. The results of this study showed that certain 2-(thioalkyl)-1H-methylbenzimidazole and 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl)benzimidazole derivatives possess antibacterial activities against clinical strains, such as Escherichia coli, Klebsiella pneumonia (Gram-negative bacteria), Staphylococcus aureus and Pseudomonas aeruginosa (Gram-positive bacteria). Following these favorable results, we extended the antibacterial evaluation of this series of molecules to environmental strains. The aim of this study was to assess the impact of the methyl-piperidine group fixed at position-1 of this new series of benzimidazoles on the antibacterial activity of environmental strains. In addition, we first evaluated the antibacterial activity of four 2-(thioalkyl)methylbenzimidazole derivatives and then that of five 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives. This study allowed us to show that compounds 1d and 1e could inhibit bacterial growth in vitro of the Enterobacteria P1 strain with inhibition diameters of 17.3 ± 0.6 mm and 10 ± 0.0 mm, respectively. However, addition of methyl-piperidinyl in this series showed that five (5) of 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives had an inhibitory effect on the in vitro growth of bacterial strains used except on Enterobacteria P2 with inhibition diameters between 10.0 ± 0.8 mm and 27.9 ± 1.4 mm. The introduction of the methyl-piperidinyl group at the 1-position of 2-(thioalkyl)-1H-methylbenzimidazole derivatives greatly improved the antibacterial activity against environmental bacteria such as Escherichia coli A1, A2, A3, and A4 and two Enterobacteria P1. 展开更多
关键词 Methylbenzimidazole Derivatives Inhibit Bacterial Growth Mannich base ENTEROBACTERIA Escherichia coli
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Base Pressure Control with Semi-Circular Ribs at Critical Mach Number
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作者 Ambareen Khan Sher Afghan Khan +2 位作者 Mohammed Nishat Akhtar Abdul Aabid Muneer Baig 《Fluid Dynamics & Materials Processing》 EI 2024年第9期2007-2028,共22页
When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necess... When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necessary in both scenarios.In this work,semi-circular ribs with varying diameters(2,4,and 6 mm)positioned at six distinct positions(0.5D,1D,1.5D,2D,3D,and 4D)inside a square duct with a side of 15 mm are proposed as an efficient way to apply the passive control technique.In-depth research is done on optimising rib size for various rib sites.According to this study,the base pressure rises as rib height increases.Furthermore,the optimal location for the semi-circular ribs with a diameter of 2 mm is at 0.5D.The 1D location appears to be optimal for the 4 mm size as well.For the 6 mm size,however,the 4D position fills this function. 展开更多
关键词 base pressure nozzle pressure ratio base drag sonic Mach number passive control
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Influence of external nitrogen-containing donors on polymerization behavior of neodymium-based cis-1,4-polybutadiene rubber
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作者 LI Xin DONG Jing +3 位作者 HAN Zhuo-ling WANG Feng ZHANG Xue-quan LIU Heng 《合成橡胶工业》 CAS 2024年第5期438-438,共1页
Neodymium(Nd)-based catalyst in butadiene(Bd)polymerization has drawn interests due to its availability in affording higher cis-1,4-unit selectivity than transition metal(Ti,Co,Ni,etc.)-based catalysts[1-2].Such outst... Neodymium(Nd)-based catalyst in butadiene(Bd)polymerization has drawn interests due to its availability in affording higher cis-1,4-unit selectivity than transition metal(Ti,Co,Ni,etc.)-based catalysts[1-2].Such outstanding high cis-1,4-unit selecti-vity is hypothetically originated from the presence of 4 f orbitals,that can participate in monomer coordination and thereby govern subsequent enchainment manners.This unique characteristic also renders the active species highly susceptible to Lewis bases,and may impact the overall selectivity as well as polyme-rization behavior after coordination.Nevertheless,it is still a virgin area in such a field,and the influence of Lewis bases on Nd-based diene polymerizations is still a black box.Based on this consideration,how nitrogen-containing donors(D)impacts the overall behaviors of Nd-mediated Bd polymerizations is disclosed. 展开更多
关键词 POLYMERIZATION bases SELECTIVITY
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Elastic wave insulation and propagation control based on the programmable curved-beam periodic structure
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作者 Jiajia MAO Hong CHENG Tianxue MA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第10期1791-1806,共16页
Curved-beams can be used to design modular multistable metamaterials(MMMs)with reprogrammable material properties,i.e.,programmable curved-beam periodic structure(PCBPS),which is promising for controlling the elastic ... Curved-beams can be used to design modular multistable metamaterials(MMMs)with reprogrammable material properties,i.e.,programmable curved-beam periodic structure(PCBPS),which is promising for controlling the elastic wave propagation.The PCBPS is theoretically equivalent to a spring-oscillator system to investigate the mechanism of bandgap,analyze the wave propagation mechanisms,and further form its geometrical and physical criteria for tuning the elastic wave propagation.With the equivalent model,we calculate the analytical solutions of the dispersion relations to demonstrate its adjustability,and investigate the wave propagation characteristics through the PCBPS.To validate the equivalent system,the finite element method(FEM)is employed.It is revealed that the bandgaps of the PCBPS can be turned on-and-off and shifted by varying its physical and geometrical characteristics.The findings are highly promising for advancing the practical application of periodic structures in wave insulation and propagation control. 展开更多
关键词 curved-beam based periodic structure equivalent stiffness spring-oscillator system dispersion relation wave propagation
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Prediction of Damping Capacity Demand in Seismic Base Isolators via Machine Learning
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作者 Ayla Ocak Umit Isıkdag +3 位作者 Gebrail Bekdas Sinan Melih Nigdeli Sanghun Kim ZongWoo Geem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2899-2924,共26页
Base isolators used in buildings provide both a good acceleration reduction and structural vibration control structures.The base isolators may lose their damping capacity over time due to environmental or dynamic effe... Base isolators used in buildings provide both a good acceleration reduction and structural vibration control structures.The base isolators may lose their damping capacity over time due to environmental or dynamic effects.This deterioration of them requires the determination of the maintenance and repair needs and is important for the long-termisolator life.In this study,an artificial intelligence prediction model has been developed to determine the damage and maintenance-repair requirements of isolators as a result of environmental effects and dynamic factors over time.With the developed model,the required damping capacity of the isolator structure was estimated and compared with the previously placed isolator capacity,and the decrease in the damping property was tried to be determined.For this purpose,a data set was created by collecting the behavior of structures with single degrees of freedom(SDOF),different stiffness,damping ratio and natural period isolated from the foundation under far fault earthquakes.The data is divided into 5 different damping classes varying between 10%and 50%.Machine learning model was trained in damping classes with the data on the structure’s response to random seismic vibrations.As a result of the isolator behavior under randomly selected earthquakes,the recorded motion and structural acceleration of the structure against any seismic vibration were examined,and the decrease in the damping capacity was estimated on a class basis.The performance loss of the isolators,which are separated according to their damping properties,has been tried to be determined,and the reductions in the amounts to be taken into account have been determined by class.In the developed prediction model,using various supervised machine learning classification algorithms,the classification algorithm providing the highest precision for the model has been decided.When the results are examined,it has been determined that the damping of the isolator structure with the machine learning method is predicted successfully at a level exceeding 96%,and it is an effective method in deciding whether there is a decrease in the damping capacity. 展开更多
关键词 Vibration control base isolation machine learning damping capacity
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Improving Satellite-Retrieved Cloud Base Height with Ground-Based Cloud Radar Measurements
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作者 Zhonghui TAN Ju WANG +3 位作者 Jianping GUO Chao LIU Miao ZHANG Shuo MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2131-2140,共10页
Cloud base height(CBH) is a crucial parameter for cloud radiative effect estimates, climate change simulations, and aviation guidance. However, due to the limited information on cloud vertical structures included in p... Cloud base height(CBH) is a crucial parameter for cloud radiative effect estimates, climate change simulations, and aviation guidance. However, due to the limited information on cloud vertical structures included in passive satellite radiometer observations, few operational satellite CBH products are currently available. This study presents a new method for retrieving CBH from satellite radiometers. The method first uses the combined measurements of satellite radiometers and ground-based cloud radars to develop a lookup table(LUT) of effective cloud water content(ECWC), representing the vertically varying cloud water content. This LUT allows for the conversion of cloud water path to cloud geometric thickness(CGT), enabling the estimation of CBH as the difference between cloud top height and CGT. Detailed comparative analysis of CBH estimates from the state-of-the-art ECWC LUT are conducted against four ground-based millimeter-wave cloud radar(MMCR) measurements, and results show that the mean bias(correlation coefficient) is0.18±1.79 km(0.73), which is lower(higher) than 0.23±2.11 km(0.67) as derived from the combined measurements of satellite radiometers and satellite radar-lidar(i.e., Cloud Sat and CALIPSO). Furthermore, the percentages of the CBH biases within 250 m increase by 5% to 10%, which varies by location. This indicates that the CBH estimates from our algorithm are more consistent with ground-based MMCR measurements. Therefore, this algorithm shows great potential for further improvement of the CBH retrievals as ground-based MMCR are being increasingly included in global surface meteorological observing networks, and the improved CBH retrievals will contribute to better cloud radiative effect estimates. 展开更多
关键词 cloud base height passive radiometer ground-based cloud radar remote sensing
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Role of micro-Ca/In alloying in tailoring the microstructural characteristics and discharge performance of dilute Mg-Bi-Sn-based alloys as anodes for Mg-air batteries
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作者 Fei-er Shangguan Wei-li Cheng +6 位作者 Yu-hang Chen Ze-qin Cui Hui Yu Hong-xia Wang Li-fei Wang Hang Li Hua Hou 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期251-266,共16页
The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are e... The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are evaluated.The grain size and texture intensity of the Mg-Bi-Sn-based alloys are significantly decreased after the Ca/In alloying,particularly for the In-containing alloy.Note that,in addition to nanoscale Mg_(3)Bi_(2)phase,a new microscale Mg_(2)Bi_(2)Ca phase forms in the Ca-containing alloy.The electrochemical test results demonstrate that Ca/In micro-alloying can enhance the electrochemical activity.Using In to alloy the Mg-Bi-Sn-based alloy is effective in restricting the cathodic hydrogen evolution(CHE)kinetics,leading to a low self-corrosion rate,while severe CHE occurred after Ca alloying.The micro-alloying of Ca/In to Mg-Bi-Sn-based alloy strongly deteriorates the compactness of discharge products film and mitigates the"chunk effect"(CE),hence the cell voltage,anodic efficiency as well as discharge capacity are greatly improved.The In-containing alloy exhibits outstanding discharge performance under the combined effect of the modified microstructure and discharge products,thus making it a potential anode material for primary Mg-air battery. 展开更多
关键词 Mg-air batteries Mg-Bi-Sn based alloys Electrochemical behaviors Discharge properties
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RoBGP:A Chinese Nested Biomedical Named Entity Recognition Model Based on RoBERTa and Global Pointer
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作者 Xiaohui Cui Chao Song +4 位作者 Dongmei Li Xiaolong Qu Jiao Long Yu Yang Hanchao Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第3期3603-3618,共16页
Named Entity Recognition(NER)stands as a fundamental task within the field of biomedical text mining,aiming to extract specific types of entities such as genes,proteins,and diseases from complex biomedical texts and c... Named Entity Recognition(NER)stands as a fundamental task within the field of biomedical text mining,aiming to extract specific types of entities such as genes,proteins,and diseases from complex biomedical texts and categorize them into predefined entity types.This process can provide basic support for the automatic construction of knowledge bases.In contrast to general texts,biomedical texts frequently contain numerous nested entities and local dependencies among these entities,presenting significant challenges to prevailing NER models.To address these issues,we propose a novel Chinese nested biomedical NER model based on RoBERTa and Global Pointer(RoBGP).Our model initially utilizes the RoBERTa-wwm-ext-large pretrained language model to dynamically generate word-level initial vectors.It then incorporates a Bidirectional Long Short-Term Memory network for capturing bidirectional semantic information,effectively addressing the issue of long-distance dependencies.Furthermore,the Global Pointer model is employed to comprehensively recognize all nested entities in the text.We conduct extensive experiments on the Chinese medical dataset CMeEE and the results demonstrate the superior performance of RoBGP over several baseline models.This research confirms the effectiveness of RoBGP in Chinese biomedical NER,providing reliable technical support for biomedical information extraction and knowledge base construction. 展开更多
关键词 BIOMEDICINE knowledge base named entity recognition pretrained language model global pointer
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Laboratory Evaluation of Performance Recovery of Aged SBS-modified Asphalt Using Regenerants with Different Base Oil Components
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作者 Li Hongzhen Li Shengbin +3 位作者 Feng Zhuangzhuang Jiang Mengmeng Li Ning Dong Fuqiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期98-107,共10页
In this study,the regenerative effects of different regenerants on aged SBS-modified asphalt from different perspectives were investigated,including their conventional properties,viscoelastic behavior,creep-related pr... In this study,the regenerative effects of different regenerants on aged SBS-modified asphalt from different perspectives were investigated,including their conventional properties,viscoelastic behavior,creep-related properties,and micromorphology.Base oils composed of different proportions of aromatic and saturated hydrocarbons as well as the styrene-butadiene-styrene(SBS)restorer were used to prepare the regenerants.The results showed that the components of the base oil of the regenerant played a crucial role in determining the characteristics and performance of the recycled SBSmodified asphalt.Regenerants containing a high proportion of aromatics dissolved the hard segment in the SBS restorer,thereby delaying the effect of a reduction in the regenerants on the performance of the aged asphalts at a high temperature.Regenerants containing a high proportion of saturates dissolved the soft segment in the SBS restorer to enhance the lowtemperature performance of the recycled asphalts.In addition,the stress sensitivity of the recycled asphalts increased with the fraction of aromatics in the regenerant.As the aromatic content of the base oil components of the regenerants increased and their saturate content decreased,the state of dispersion of the SBS phase in the recycled SBS-modified asphalts improved.The optimal content of aromatics in the base oil of the regenerants should be set in the range of 33%to 47%to ensure the adequate performance of the recycled asphalts and a high efficiency of the SBS restorer. 展开更多
关键词 aged SBS-modified asphalt regeneration mechanisms base oil rheological properties MORPHOLOGY
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Prediction of Lubricant Physicochemical Properties Based on Gaussian Copula Data Expansion
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作者 Feng Xin Yang Rui +1 位作者 Xie Peiyuan Xia Yanqiu 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期161-174,共14页
The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO... The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO40,and PriEco3000 component in a composite base oil system on the performance of lubricants.The study was conducted under small laboratory sample conditions,and a data expansion method using the Gaussian Copula function was proposed to improve the prediction ability of the hybrid model.The study also compared four optimization algorithms,sticky mushroom algorithm(SMA),genetic algorithm(GA),whale optimization algorithm(WOA),and seagull optimization algorithm(SOA),to predict the kinematic viscosity at 40℃,kinematic viscosity at 100℃,viscosity index,and oxidation induction time performance of the lubricant.The results showed that the Gaussian Copula function data expansion method improved the prediction ability of the hybrid model in the case of small samples.The SOA-GBDT hybrid model had the fastest convergence speed for the samples and the best prediction effect,with determination coefficients(R^(2))for the four indicators of lubricants reaching 0.98,0.99,0.96 and 0.96,respectively.Thus,this model can significantly reduce the model’s prediction error and has good prediction ability. 展开更多
关键词 base oil data augmentation machine learning performance prediction seagull algorithm
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Buckling Optimization of Curved Grid Stiffeners through the Level Set Based Density Method
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作者 Zhuo Huang Ye Tian +2 位作者 Yifan Zhang Tielin Shi Qi Xia 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期711-733,共23页
Stiffened structures have great potential for improvingmechanical performance,and the study of their stability is of great interest.In this paper,the optimization of the critical buckling load factor for curved grid s... Stiffened structures have great potential for improvingmechanical performance,and the study of their stability is of great interest.In this paper,the optimization of the critical buckling load factor for curved grid stiffeners is solved by using the level set based density method,where the shape and cross section(including thickness and width)of the stiffeners can be optimized simultaneously.The grid stiffeners are a combination ofmany single stiffenerswhich are projected by the corresponding level set functions.The thickness and width of each stiffener are designed to be independent variables in the projection applied to each level set function.Besides,the path of each single stiffener is described by the zero iso-contour of the level set function.All the single stiffeners are combined together by using the p-norm method to obtain the stiffener grid.The proposed method is validated by several numerical examples to optimize the critical buckling load factor. 展开更多
关键词 STIFFENER buckling optimization shape and cross section level set based density
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Solid-state NMR of the retinal protonated Schiff base in microbial rhodopsins
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作者 Sari Kumagai Izuru Kawamura 《Magnetic Resonance Letters》 2024年第3期11-18,共8页
Rhodopsin is a seven-helical transmembrane protein with a retinal chromophore covalently bound to a conserved lysine in helix G via a retinal protonated Schiff base(RPSB).Microbial rhodopsins absorb light through chro... Rhodopsin is a seven-helical transmembrane protein with a retinal chromophore covalently bound to a conserved lysine in helix G via a retinal protonated Schiff base(RPSB).Microbial rhodopsins absorb light through chromophore and play a fundamental role in optogenetics.Numerous microbial rhodopsins have been discovered,contributing to diverse functions and colors.Solid-state NMR spectroscopy has been instrumental in elucidating the conformation of chromophores and the three-dimensional structure of microbial rhodopsins.This review focuses on the 15N chemical shift values of RPSB and summarizes recent progress in the field.We displayed the correlation between the 15N isotropic chemical shift values of RPSB and the maximum absorption wavelength of rhodopsin using solid-state NMR spectroscopy. 展开更多
关键词 Membrane proteins Microbial rhodopsin RETINAL Solid-state NMR Protonated Schiff base
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