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A comprehensive review of lunar lava tube base construction and field research on a potential Earth test site 被引量:1
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作者 Yujie Feng Peng-Zhi Pan +3 位作者 Xuhai Tang Zhaofeng Wang Yuxin Li Altaf Hussain 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1201-1216,共16页
The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission... The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission.Lunar lava tubes are special underground caves formed by volcanic eruptions and are considered as ideal natural shelters and scientific laboratories for lunar base construction.This paper begins with an in-depth overview of the geological origins,exploration history,and distribution locations of lunar lava tubes.Subsequently,it delves into the presentation of four distinctive advantages and typical concepts for constructing bases within lava tubes,summarizing the ground-based attempts made thus far in lunar lava tube base construction.Field studies conducted on a lava tube in Hainan revealed rock compositions similar to those found during the Apollo missions and clear lava tube structures,making it a promising analog site.Lastly,the challenges and opportunities encountered in the field of geotechnical engineering regarding the establishment of lunar lava tube bases are discussed,encompassing cave exploration technologies,in-situ testing methods,geomechanical properties under lunar extreme environments,base design and structural stability assessment,excavation and reinforcement techniques,and simulated Earth-based lava tube base. 展开更多
关键词 Lunar lava tube Lunar base construction Extraterrestrial cave exploration Earth analog site
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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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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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Accountable capability improvement based on interpretable capability evaluation using belief rule base
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作者 LI Xuan JIANG Jiang +2 位作者 SUN Jianbin YU Haiyue CHANG Leilei 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1231-1244,共14页
A new approach is proposed in this study for accountable capability improvement based on interpretable capability evaluation using the belief rule base(BRB).Firstly,a capability evaluation model is constructed and opt... A new approach is proposed in this study for accountable capability improvement based on interpretable capability evaluation using the belief rule base(BRB).Firstly,a capability evaluation model is constructed and optimized.Then,the key sub-capabilities are identified by quantitatively calculating the contributions made by each sub-capability to the overall capability.Finally,the overall capability is improved by optimizing the identified key sub-capabilities.The theoretical contributions of the proposed approach are as follows.(i)An interpretable capability evaluation model is constructed by employing BRB which can provide complete access to decision-makers.(ii)Key sub-capabilities are identified according to the quantitative contribution analysis results.(iii)Accountable capability improvement is carried out by only optimizing the identified key sub-capabilities.Case study results show that“Surveillance”,“Positioning”,and“Identification”are identified as key sub-capabilities with a summed contribution of 75.55%in an analytical and deducible fashion based on the interpretable capability evaluation model.As a result,the overall capability is improved by optimizing only the identified key sub-capabilities.The overall capability can be greatly improved from 59.20%to 81.80%with a minimum cost of 397.Furthermore,this paper also investigates how optimizing the BRB with more collected data would affect the evaluation results:only optimizing“Surveillance”and“Positioning”can also improve the overall capability to 81.34%with a cost of 370,which thus validates the efficiency of the proposed approach. 展开更多
关键词 accountable capability improvement interpretable capability evaluation belief rule base(BRB).
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Layer by Layer Self-assembly Fiber-based Flexible Electrochemical Transistor
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作者 谭艳 HAO Panpan +2 位作者 HE Yang ZHU Rufeng 王跃丹 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期937-944,共8页
Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface mo... Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface morphology and electric property was investigated.The results confirmed the dense membrane of PEDOT:PSS and the lamellar structure of PDDA-rGO on the fibers.It has excellent electrical conductivity and mechanical properties.The fiber based electrochemical transistor(FECTs)prepared by the composite conductive fiber has a maximum output current of 8.7 mA,a transconductance peak of 10 mS,an on time of 1.37 s,an off time of 1.6 s and excellent switching stability.Most importantly,the devices by layer by layer self-assembly technology opens a path for the true integration of organic electronics with traditional textile technologies and materials,laying the foundation for their later widespread application. 展开更多
关键词 layer by layer SELF-ASSEMBLY fiber based organic electrochemical transistor reduced graphene oxide PEDOT:PSS
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Investigating the Correlation between Patient Education on Web-Based Portal Functionality and the Reduction in 30-Day Hospital Readmission Rates
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作者 Aradhyaa Mathur 《International Journal of Clinical Medicine》 CAS 2024年第10期465-477,共13页
Background: The growing use of web-based patient portals offers patients valuable tools for accessing health information, communicating with healthcare providers, and engaging in self-management. However, the influenc... Background: The growing use of web-based patient portals offers patients valuable tools for accessing health information, communicating with healthcare providers, and engaging in self-management. However, the influence of educating patients on these portals’ functionality on clinical outcomes, such as all-cause readmission rates, remains underexplored. Objective: This research proposal tested the hypothesis that educating a subset of patients with Chronic Obstructive Pulmonary Disease (COPD) and Congestive Heart Failure (CHF), on how to effectively access and utilize the functionality of web-based patient portals can reduce all-cause readmission rates. Methods: We performed a prospective, quasi-experimental study at Bon Secours St. Mary’s Hospital in Richmond, Virginia, USA;dividing participants into an intervention group, receiving education about accessing and navigating “My Chart”, the Bon Secours Web based portal, and a control group, receiving standard care. We then compared 30-day readmission rates, patient engagement, and self-management behaviors between the groups. Data was analyzed using statistical tests to assess the intervention’s impact. Results: We projected that educated patients will exhibit lower readmission rates, improved engagement, and better self-management. The results of the study showed that there was a significant decrease in 30-day readmissions in the intervention group in comparison with the control group (22.7% and 40.9%, respectively). This reduction of 18. 2% of readmissions evaluated here for a trial of meaningful clinical effect is statistically insignificant (p = 0. 184). The practical significance of the intervention is considered small-to-moderate (Cramer V = 0. 20) suggesting that the observed difference has a potential clinical importance even though the difference was not statistically significant. Conclusion: These results imply that the proposed educational intervention might have a positive impact on readmissions;nonetheless, the patient’s characteristics that make him or her capable of readmission cannot be changed and are assessed by the RoR (Risk of Readmission) score. The potential impact of the intervention may be offset, in part, by these baseline risk factors. The study’s power may be limited by sample size, potentially affecting the detection of significant differences. Future studies with larger, multi-center samples and longer follow-up periods are recommended to confirm these findings. 展开更多
关键词 All Cause Hospital Readmission Chronic Obstructive Pulmonary Disease Congestive Heart Failure Web based Patient Portal Mobile Device Proficiency Questionnaire (MDPQ) 16 Risk of Readmission (RoR) Score Patient Education
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A Health State Prediction Model Based on Belief Rule Base and LSTM for Complex Systems
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作者 Yu Zhao Zhijie Zhou +3 位作者 Hongdong Fan Xiaoxia Han JieWang Manlin Chen 《Intelligent Automation & Soft Computing》 2024年第1期73-91,共19页
In industrial production and engineering operations,the health state of complex systems is critical,and predicting it can ensure normal operation.Complex systems have many monitoring indicators,complex coupling struct... In industrial production and engineering operations,the health state of complex systems is critical,and predicting it can ensure normal operation.Complex systems have many monitoring indicators,complex coupling structures,non-linear and time-varying characteristics,so it is a challenge to establish a reliable prediction model.The belief rule base(BRB)can fuse observed data and expert knowledge to establish a nonlinear relationship between input and output and has well modeling capabilities.Since each indicator of the complex system can reflect the health state to some extent,the BRB is built based on the causal relationship between system indicators and the health state to achieve the prediction.A health state prediction model based on BRB and long short term memory for complex systems is proposed in this paper.Firstly,the LSTMis introduced to predict the trend of the indicators in the system.Secondly,the Density Peak Clustering(DPC)algorithmis used todetermine referential values of indicators for BRB,which effectively offset the lack of expert knowledge.Then,the predicted values and expert knowledge are fused to construct BRB to predict the health state of the systems by inference.Finally,the effectiveness of the model is verified by a case study of a certain vehicle hydraulic pump. 展开更多
关键词 Health state predicftion complex systems belief rule base expert knowledge LSTM density peak clustering
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Self-similarity Based Editing of 3D Surface Textures Using Height and Albedo Maps
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作者 DONG Junyu REN Jing CHEN Guojiang 《Journal of Ocean University of China》 SCIE CAS 2007年第2期209-212,共4页
This paper presents an inexpensive method for self-similarity based editing of real-world 3D surface textures by using height and albedo maps. Unlike self-similarity based 2D texture editing approaches which only make... This paper presents an inexpensive method for self-similarity based editing of real-world 3D surface textures by using height and albedo maps. Unlike self-similarity based 2D texture editing approaches which only make changes to pixel color or inten- sity values, this technique also allows surface geometry and reflectance of the captured 3D surface textures to be edited and relit us- ing illumination conditions and viewing angles that differ from those of the original. A single editing operation at a given location affects all similar areas and produces changes on all images of the sample rendered under different conditions. Since surface height and albedo maps can be used to describe seabed topography and geologic features, which play important roles in many oceanic proc- esses, the proposed method can be effectively employed in applications regarding visualization and simulation of oceanic phenom- ena. 展开更多
关键词 3D surface texture SELF-SIMILARITY texture editing bump mapping visualization virtual reality
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Frequency and Factors Associated with Gender-Based Violence in the Northern Region of Benin from 2016 to 2022
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作者 Comlan Albert Dovonou Cossi Adébayo Alassani +4 位作者 Khadidjatou Saké Alassan Sero Tamou Cossi Angelo Attinsounon Séraphin Ahoui Finangnon Armand Wanvoegbe 《Open Journal of Internal Medicine》 2024年第3期287-298,共12页
Introduction: Gender-based violence constitutes a public health problem. The objective of this study is to determine the frequency and factors associated with gender-based violence. Study Framework and Method: This wa... Introduction: Gender-based violence constitutes a public health problem. The objective of this study is to determine the frequency and factors associated with gender-based violence. Study Framework and Method: This was a retrospective, descriptive, cross-sectional study with an analytical aim over the period from January 2016 to December 2022. The study took place in the Integrated Support Center for Victims and Survivors of Gender-Based Violence located in the Departmental University Hospital Center of Borgou and Alibori. The study population consisted of people who were victims of gender-based violence in the northern region of Benin, regardless of their age and gender. Results: The study population consisted of 1198 subjects. The average age of the victims was 21.76 ± 10.02;female victims represented 96.4%, with a sex ratio equal to 0.037 (43/1155). Sexual violence was the most represented (50.25%), followed by psychological (29.30%), physical (24.37%), economic (13.77%) and property (2%). The factors associated with violence were married people and monthly income (physical violence), minors, female gender and single people (sexual violence), polygamous households and monthly income (economic violence), the absence of children burden, married people and monthly income (psychological violence), married people (property violence). Conclusion: Gender-based violence is frequent in the North of Benin and is dominated by sexual violence. The victims are mainly female. 展开更多
关键词 FREQUENCY Gender-based Violence North benin
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Hot corrosion behavior of Ni-xCr-6.8Al based alloys 被引量:7
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作者 韩朝 刘咏 +2 位作者 王岩 李维杰 汤慧萍 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2348-2357,共10页
The hot corrosion behaviors of as-cast and preoxidized Ni-xCr-6.8Al based alloys in the mixture of Na2SO4+25% NaCl at 873 K were studied. The results show that the mass loss of Ni-xCr-6.8Al based alloys decreases wit... The hot corrosion behaviors of as-cast and preoxidized Ni-xCr-6.8Al based alloys in the mixture of Na2SO4+25% NaCl at 873 K were studied. The results show that the mass loss of Ni-xCr-6.8Al based alloys decreases with the increase of Cr content. Preoxidation improves the resistance to corrosion regardless of the concentration of Cr. The kinetics of as-cast Ni-12Cr-6.8Al and Ni-16Cr-6.8Al based alloys fits the parabolic law well, while that of the as-cast Ni-20Cr-6.8Al based alloy fits the power law. The kinetics of all the preoxidized samples obey the logarithmic law. The mechanism of the as-cast alloys can be well explained by the acid-base melting model. The behavior of the preoxidized alloys is found to be mainly determined by the properties of the oxide layer formed during the preoxidation to a large extend. 展开更多
关键词 Ni-Cr-Al based alloy hot corrosion Cr content PREOXIDATION KINETICS corrosion mechanism
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Effects of temperature on fracture behavior of Al-based in-situ composites reinforced with Mg_2Si and Si particles fabricated by centrifugal casting 被引量:5
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作者 李波 王开 +3 位作者 刘明翔 薛寒松 朱子宗 刘昌明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期923-930,共8页
An aluminum-based in-situ composites reinforced with Mg2Si and Si particles were produced by centrifugal casting A1-20Si-5Mg alloy. The microstructure of the composites was examined, and the effects of temperature on ... An aluminum-based in-situ composites reinforced with Mg2Si and Si particles were produced by centrifugal casting A1-20Si-5Mg alloy. The microstructure of the composites was examined, and the effects of temperature on fracture behavior of the composite were investigated. The results show that the average fraction of primary Si and Mg2Si particles in the composites is as high as 38%, and ultimate tensile strengths (UTS) of the composites first increase then decrease with the increase of test temperature. Microstructures of broken specimens show that both the particle fracture and the interface debonding affect the fracture behavior of the composites, and the interface debonding becomes the dominant fracture mechanism with increasing test temperature. Comparative results indicate that rich particles in the composites and excellent interface strength play great roles in enhancing tensile property by preventing the movement of dislocations. 展开更多
关键词 aluminum based in-situ composites fracture behavior centrifugal casting high temperature
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The Influence of Carbon Nanotubes and Nano-Silica Fume on Enhancing the Damping and Mechanical Properties of Cement-Based Materials
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作者 Bin Liu Norhaiza Nordin +2 位作者 Jiyang Wang Jingwei Wu Xiuliang Liu 《Materials Sciences and Applications》 2024年第9期399-416,共18页
This paper conducted experimental studies on the damping and mechanical properties of carbon nanotube-nanosilica-cement composite materials with different carbon nanotube contents. The damping and mechanical propertie... This paper conducted experimental studies on the damping and mechanical properties of carbon nanotube-nanosilica-cement composite materials with different carbon nanotube contents. The damping and mechanical properties enhancement mechanisms were analyzed and compared through the porosity structure test, XRD analysis, and scanning electron microscope observation. The results show that the introduction of nanosilica significantly improves the dispersion of carbon nanotubes in the cement matrix. At the same time, the addition of nanosilica not only effectively reduces the critical pore size and average pore size of the cement composite material, but also exhibits good synergistic effects with carbon nanotubes, which can significantly optimize the pore structure. Finally, a rationalization suggestion for the co-doping of nanosilica and carbon nanotubes was given to achieve a significant increase in the flexural strength, compressive strength and loss factor of cement-based materials. 展开更多
关键词 Cement-based Composites Carbon Nanotubes Nano Silica Fume Damping Property Mechanical Property
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Friction and wear behaviors of Nb-Ti-Si-Cr based ultrahigh temperature alloy and its Zr-Y jointly modified silicide coatings 被引量:3
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作者 李轩 郭喜平 乔彦强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1892-1901,共10页
Zr-Y jointly modified silicide coatings were prepared on an Nb-Ti-Si-Cr based ultrahigh temperature alloy by pack cementation process. The wear behaviors of both the base alloy and coatings were comparatively studied ... Zr-Y jointly modified silicide coatings were prepared on an Nb-Ti-Si-Cr based ultrahigh temperature alloy by pack cementation process. The wear behaviors of both the base alloy and coatings were comparatively studied at room temperature and 800 ℃ using SiC balls as the counterpart. The Zr-Y jointly modified silicide coating is mainly composed of a thick (Nb,X)Si2 outer layer and a thin (Ti,Nb)5Si4 inner layer. The coatings possess much higher microhardness than the base alloy. The wear rates of both the base alloy and coatings increase with increasing the sliding loads. However, the coatings have much lower wear rates than the base alloy under the same sliding conditions. The coatings have superior anti-friction property, and can provide effective protection for the base alloy at both room temperature and 800 ℃ in air. 展开更多
关键词 Nb-Ti-Si-Cr based alloy Zr-Y modified silicide coating friction and wear wear mechanism
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Model-Based Systems Engineering Approach to Design a Human Settlement to Better Serve Displaced People
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作者 Anicet Adjahossou 《Open Journal of Applied Sciences》 2024年第4期865-880,共16页
The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficultie... The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficulties in providing social services that meet the required standards, and the prolongation of emergencies. Despite this challenging context, short-term considerations continue to guide their planning and management rather than more integrated, longer-term perspectives, thus preventing viable, sustainable development. Over the years, the design of humanitarian settlements has not been adapted to local contexts and perspectives, nor to the dynamics of urbanization and population growth and data. In addition, the current approach to temporary settlement harms the environment and can strain limited resources. Inefficient land use and ad hoc development models have compounded difficulties and generated new challenges. As a result, living conditions in settlements have deteriorated over the last few decades and continue to pose new challenges. The stakes are such that major shortcomings have emerged along the way, leading to disruption, budget overruns in a context marked by a steady decline in funding. However, some attempts have been made to shift towards more sustainable approaches, but these have mainly focused on vague, sector-oriented themes, failing to consider systematic and integration views. This study is a contribution in addressing these shortcomings by designing a model-driving solution, emphasizing an integrated system conceptualized as a system of systems. This paper proposes a new methodology for designing an integrated and sustainable human settlement model, based on Model-Based Systems Engineering and a Systems Modeling Language to provide valuable insights toward sustainable solutions for displaced populations aligning with the United Nations 2030 agenda for sustainable development. 展开更多
关键词 Humanitarian Settlement Human Settlement Sustainability Systems Engineering Model-based Systems Engineering Systems Modeling Language
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Hot corrosion behavior of Ni–16Cr–xAl based alloys in mixture of Na_2SO_4-NaCl at 600 ℃ 被引量:4
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作者 李维杰 刘咏 +2 位作者 王岩 韩朝 汤慧萍 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2617-2625,共9页
The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resi... The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resistance to hot corrosion were examined. The hot corrosion resistance of Ni–16Cr–xAl based alloy with Al addition from 4.5% to 9.0% increases with increasing Al content. The alloy with Al content of 9.0% shows the highest hot corrosion resistance among the examined alloys because more β–NiAl phases are obtained to sustain the Al2O3 scale repaired during hot corrosion. Pre-oxidized specimens have a superior hot corrosion resistance compared with the as-cast specimens, due to a protective oxide scale formed after pre-treatment. 展开更多
关键词 Ni–16Cr–xAl based alloys PRE-OXIDATION Na2SO4–25% NaCl mixed salt hot-corrosion mechanism
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Effect of electropulsing treatment on corrosion behavior of nickel base corrosion-resistant alloy
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作者 刘杨 王磊 +2 位作者 刘红艳 张北江 赵光普 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期1970-1975,共6页
Electropulsing treatment(EPT) was performed on a nickel base corrosion resistant alloy during aging.The effect of EPT on the microstructure and corrosion resistance of the alloy and the mechanisms were investigated.... Electropulsing treatment(EPT) was performed on a nickel base corrosion resistant alloy during aging.The effect of EPT on the microstructure and corrosion resistance of the alloy and the mechanisms were investigated.The results show that the intergranular corrosion resistance can be improved substantially without the degradation of mechanical properties of the alloy by EPT.The EPT has an effect of enhancing the interface diffusion rate of the alloying element,which is higher than the body diffusion rate.And thus discontinuous precipitation of M23C6 type carbides appears at the grain boundary in the alloy by EPT,which decreases the depletion extent of the alloying elements at the grain boundary substantially.As a result,the intergranular corrosion resistance of the alloy can be improved by the EPT without any degradation of mechanical properties. 展开更多
关键词 nickel base alloy ELECTROPULSING discontinuous precipitation intergranular corrosion
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Base editing in plants: Current status and challenges 被引量:10
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作者 Sutar Suhas Bharat Shaoya Li +2 位作者 Jingying Li Lei Yan Lanqin Xia 《The Crop Journal》 SCIE CAS CSCD 2020年第3期384-395,共12页
Genome editing technologies have revolutionized the field of plant science by enabling targeted modification of plant genomes and are emerging as powerful tools for both plant gene functional analyses and crop improve... Genome editing technologies have revolutionized the field of plant science by enabling targeted modification of plant genomes and are emerging as powerful tools for both plant gene functional analyses and crop improvement. Although homology-directed repair(HDR)is a feasible approach to achieve precise gene replacement and base substitution in some plant species, the dominance of the non-homologous end joining pathway and low efficiency of HDR in plant cells have limited its application. Base editing has emerged as an alternative tool to HDR-mediated replacement, facilitating precise editing of plant genome by converting one single base to another in a programmable manner without a doublestranded break and a donor repair template. In this review, we summarize the latest developments in base-editing technologies as well as their underlying mechanisms. We review current applications of these technologies in plant species. Finally, we address the challenges and future perspectives of this emerging technology in plants. 展开更多
关键词 base editing in plants Current status and challenges
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Three novel alleles of OsGS1 developed by base-editing-mediated artificial evolution confer glufosinate tolerance in rice 被引量:3
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作者 Bin Ren Yongjie Kuang +7 位作者 Ziyan Xu Xuemei Wu Dawei Zhang Fang Yan Xiangju Li Xueping Zhou Guirong Wang Huanbin Zhou 《The Crop Journal》 SCIE CSCD 2023年第2期661-665,共5页
Only few glufosinate-tolerant genes,such as phosphinothricin acetyltransferase(PAT)and bialaphos resistance(bar)identified from Streptomyces,are currently available for developing genetically modified rice in agricult... Only few glufosinate-tolerant genes,such as phosphinothricin acetyltransferase(PAT)and bialaphos resistance(bar)identified from Streptomyces,are currently available for developing genetically modified rice in agricultural application.Following the rapid development of genome editing technology,generation of novel glufosinate-tolerant gene resources through artificial evolution of endogenous genes is more promising and highly desirable in rice molecular breeding program.In this study,the endogenous Glutamine synthetase1(OsGS1)was artificially evolved by base-editing-mediated gene evolution(BEMGE)in rice cells to create novel alleles conferring glufosinate tolerance in rice germplasms.Two novel glufosinate-tolerant OsGS1 alleles(OsGS1-AVPS and OsGS1-+AF)and one reported tolerant allele(OsGS1-SGTA)were successfully identified from approximately 4200 independent hygromycin-tolerant calli.Germination assays and spray tests revealed that these three OsGS1 alleles confer glufosinate tolerance in rice.Furthermore,OsGS1-AVPS and OsGS1-SGTA were quickly deployed into the elite rice cultivar Nangeng 46 through precise base editing.Overall,our results demonstrate the feasibility of developing glufosinate-tolerant rice by editing an endogenous rice gene in molecular breeding programs. 展开更多
关键词 base editing Gene evolution Glutamine synthetase Glufosinate tolerance RICE
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