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Macroscopic environmental heterogeneity and corrosion behavior derived from in vitro degradation of pure magnesium and their in vivo investigation
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作者 Lulu Zhang Kotaro Hanada Kazuhiro Kumagai 《Journal of Magnesium and Alloys》 2025年第7期3186-3197,共12页
Magnesium(Mg)alloys have attracted considerable attention as promising implant materials for biodegradable medical devices.In this study,we focused on investigating the effect of macroscopic environmental heterogeneit... Magnesium(Mg)alloys have attracted considerable attention as promising implant materials for biodegradable medical devices.In this study,we focused on investigating the effect of macroscopic environmental heterogeneity due to the degradation of Mg on its corrosion behavior.The immersion experiments using pure Mg plates,which were placed vertically in a culture medium(Dulbecco’s Modified Eagle’s Medium(DEME)+10%fetal bovine serum(FBS))for 1,5,and 10 days,were conducted.Surface analyses for the corrosion product layers and the measurements of the pH values and concentrations of eluted ions in the immersion medium around the upper and lower areas of the Mg plate were performed.The significant effect of the macroscopic environmental heterogeneity derived from Mg degradation on the corrosion behavior was demonstrated by in vitro tests.Additionally,the in vivo tests were carried out by implanting the pure Mg plates in the femur of rabbits.The in vivo results exhibited macroscopically heterogeneous Mg degradation,with areas of more severe corrosion compared to the in vitro test;it is especially noticeable during the early stage of degradation,even though the average corrosion rate was lower. 展开更多
关键词 Biodegradable Mg Corrosion behavior In vitro In vivo Environmental heterogeneity Corrosion product X-ray photoelectron spectroscopy MICRO-CT
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富血小板血浆联合射频微针治疗高原地区面部光老化的临床效果
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作者 廖程琦 张敏 郑波 《临床医学研究与实践》 2025年第28期105-108,共4页
目的观察富血小板血浆(PRP)联合射频微针治疗高原地区面部光老化的临床效果。方法选取2023年10月至2024年12月在拉萨爱思特医疗美容医院接受治疗的40例高原地区面部光老化患者,按治疗方式将其分为对照组和治疗组,每组20例。对照组采用... 目的观察富血小板血浆(PRP)联合射频微针治疗高原地区面部光老化的临床效果。方法选取2023年10月至2024年12月在拉萨爱思特医疗美容医院接受治疗的40例高原地区面部光老化患者,按治疗方式将其分为对照组和治疗组,每组20例。对照组采用射频微针治疗,治疗组采用PRP联合射频微针治疗。采集治疗前及治疗后6周的面部光谱图像,以光老化整体评分、整体美学改善量表(GAIS)来评估患者治疗前后皮肤质地、细纹、色素等综合改善情况,并记录患者满意度和不良反应。结果治疗前,两组的光老化整体评分比较,差异无统计学意义(P>0.05);治疗后,两组的光老化整体评分均低于治疗前,差异具有统计学意义(P<0.05);治疗后,治疗组的光老化整体评分低于对照组,差异具有统计学意义(P<0.05)。治疗组的可观改善率明显高于对照组,差异具有统计学意义(P<0.05)。治疗组的满意度为80.00%,对照组的满意度为60.00%。观察到的术后不良反应有红斑、肿胀、紫癜、瘀青,均在数日内自行消退。结论PRP联合射频微针治疗高原地区面部光老化安全有效。 展开更多
关键词 射频微针 富血小板血浆 高原地区 面部光老化
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注射型富血小板纤维蛋白联合超完美脉冲光治疗西藏高原地区敏感性皮肤的效果
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作者 郑波 张敏 +4 位作者 魏国祥 廖程琦 李梦琴 邓雍 李林 《临床医学研究与实践》 2025年第34期110-113,共4页
目的观察注射型富血小板纤维蛋白(i-PRF)联合超完美脉冲光(AOPT)治疗西藏高原地区敏感性皮肤的有效性及安全性。方法选取西藏高原地区敏感性皮肤患者50例,根据治疗方案差异将其分为对照组和观察组,每组25例。对照组采用单纯AOPT治疗,观... 目的观察注射型富血小板纤维蛋白(i-PRF)联合超完美脉冲光(AOPT)治疗西藏高原地区敏感性皮肤的有效性及安全性。方法选取西藏高原地区敏感性皮肤患者50例,根据治疗方案差异将其分为对照组和观察组,每组25例。对照组采用单纯AOPT治疗,观察组采用AOPT治疗后行i-PRF真皮内注射。每间隔4周治疗1次,共3次。治疗结束后对比两组患者的临床效果。结果治疗后,两组的主观症状、客观症状评分均明显降低,且观察组低于对照组(P<0.05)。观察组的治疗总有效率为96.00%,高于对照组的72.00%(P<0.05)。结论i-PRF联合AOPT能改善西藏高原地区敏感性皮肤患者的临床症状,修复皮肤屏障功能,提升治疗效果。 展开更多
关键词 注射型富血小板纤维蛋白 超完美脉冲光 敏感性皮肤 皮肤屏障 西藏 高原地区
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Effects of batch and continuous-flow operation on biotreatment of Mn(II)-containing mine drainage
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作者 Obey Gotore Miho Watanabe +5 位作者 Kunihiro Okano Naoyuki Miyata Taiki Katayama Tetsuo Yasutaka Yuki Semoto Takaya Hamai 《Journal of Environmental Sciences》 2025年第6期401-415,共15页
The biotreatment of mine drainage containing dissolved manganese(Mn)using Mn(II)-oxidizing bacteria is challenging.Sequencing-batch(SBRs)and continuous-flow reactors(CFRs)packed with limestones and inoculated with the... The biotreatment of mine drainage containing dissolved manganese(Mn)using Mn(II)-oxidizing bacteria is challenging.Sequencing-batch(SBRs)and continuous-flow reactors(CFRs)packed with limestones and inoculated with the mine-drainage microbial communitywere compared to determine the removal efficiency of Mn(II)from mine drainage.Mn(II)removal in CFRs was 11.4%±0.0%(mean±standard deviation)in the first two weeks and;it slightly increased to 13.6%±0.0%after four weeks,and more than 94%of Mn(II)was removed under the steady-state treatment phase.The performance of SBRs was more effective,wherein 24.4%±0.1%of Mn was removed in the first two weeks,and in four weeks,surpassed 66.6%±0.2%.Rapid Mn(II)removal observed in the start-up of SBR resulted from higher microbial metabolic activities.The adenosine triphosphate(ATP)content of the microbial community was four-fold more than in CFR,but comparable during the steady-state phase.The Mn-oxide deposits occurring in the SBR and CFR at steady-state were mixed phases of birnessite and woodruffite,and the average Mn oxidation valence in the SBR(+3.73)was slightly higher than that in the CFR(+3.54).During the start-up treatment,the closest relatives of Methyloversatilis,Methylibium,and Curvibacter dominated the SBR,whereas putative Mn oxidizers were associated with Hyphomicrobium,Pedobacter,Pedomicrobium,Terricaulis sp.,Sulfuritalea,and Terrimonas organisms.The growth of potential Mnoxidizing genera,including Mesorhizobium,Rhodococcus,Hydrogenophaga,Terricaulis sp.,and‘Candidatus Manganitrophus-noduliformans’was observed under the steady state.The SBR operation was effective as a prior start-up treatment for mine drainage-containing Mn(II),through which the CFR performed well as posterior bio-treatment. 展开更多
关键词 Start-up bioreactor Woodruffite-like Mn(III/VI)oxides Bacterial communities Mine drainage Manganese oxidation BIOTREATMENT
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Robust Load Frequency Control in Hybrid Power Systems Using QOSCA-Tuned PID with EV Loads
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作者 Pralay Roy Pabitra Kumar Biswas +1 位作者 Chiranjit Sain Taha Selim Ustun 《Energy Engineering》 2025年第10期4035-4060,共26页
This study presents the use of an innovative population-based algorithm called the Sine Cosine Algorithm and its metaheuristic form,Quasi Oppositional Sine Cosine Algorithm,to automatic generation control of a multipl... This study presents the use of an innovative population-based algorithm called the Sine Cosine Algorithm and its metaheuristic form,Quasi Oppositional Sine Cosine Algorithm,to automatic generation control of a multiple-source-based interconnected power system that consists of thermal,gas,and hydro power plants.The Proportional-Integral-Derivative controller,which is utilized for automated generation control in an interconnected hybrid power systemwith aDClink connecting two regions,has been tuned using the proposed optimization technique.An Electric Vehicle is taken into consideration only as an electrical load.The Quasi Oppositional Sine Cosinemethod’s performance and efficacy have been compared to the Sine Cosine Algorithm and optimal output feedback controller tuning performance.Applying the QOSCA optimization technique,which has only been shown in this study in the context of an LFC research thus far,makes this paper unique.The main objective has been used to assess and compare the dynamic performances of the recommended controller along with QOSCA optimisation technic.The resilience of the controller is examined using two different system parameters:B(frequency bias parameter)and R(governor speed regulation).The sensitivity analysis results demonstrate the high reliability of the QOSCA algorithm-based controller.Once optimal controller gains are established for nominal conditions,step load perturbations up to±10%&±25%in the nominal values of the systemparameters and operational load condition do not require adjustment of the controller.Ultimately,a scenario is examined whereby EVs are used for area 1,and a single PID controller is used rather than three. 展开更多
关键词 Automatic generation control multi-source interconnected power system electric vehicle
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Graph-Embedded Neural Architecture Search: A Variational Approach for Optimized Model Design
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作者 Kazuki Hemmi Yuki Tanigaki +1 位作者 Kaisei Hara Masaki Onishi 《Computers, Materials & Continua》 2025年第8期2245-2271,共27页
Neural architecture search(NAS)optimizes neural network architectures to align with specific data and objectives,thereby enabling the design of high-performance models without specialized expertise.However,a significa... Neural architecture search(NAS)optimizes neural network architectures to align with specific data and objectives,thereby enabling the design of high-performance models without specialized expertise.However,a significant limitation of NAS is that it requires extensive computational resources and time.Consequently,performing a comprehensive architectural search for each new dataset is inefficient.Given the continuous expansion of available datasets,there is an urgent need to predict the optimal architecture for the previously unknown datasets.This study proposes a novel framework that generates architectures tailored to unknown datasets by mapping architectures that have demonstrated effectiveness on the existing dataset into a latent feature space.As NAS is inherently represented as graph structures,we employed an encoder-decoder transformation model based on variational graph auto-encoders to perform this latent feature mapping.The encoder-decoder transformation model demonstrates strong capability in extracting features from graph structures,making it particularly well-suited for mapping NAS architectures.By training variational graph auto-encoders on existing high-quality architectures,the proposed method constructs a latent space and facilitates the design of optimal architectures for diverse datasets.Furthermore,to effectively define similarity amongarchitectures,wepropose constructing the latent spaceby incorporatingbothdataset andtaskfeatures.Experimental results indicate that our approach significantly enhances search efficiency and outperforms conventional methods in terms of model performance. 展开更多
关键词 Neural architecture search automated machine learning artificial intelligence deep learning graph neural network
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Amorphous-to-crystalline transition-induced two-step thin film growth of quasi-one-dimensional penta-telluride ZrTe_(5)
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作者 Yi Shuang Yuta Saito +3 位作者 Shogo Hatayama Paul Fons Ando Daisuke Yuji Sutou 《Journal of Materials Science & Technology》 2025年第7期246-253,共8页
Quasi-one-dimensional(quasi-1D)van der Waals(vdWs)materials,such as ZrTe_(5),exhibit unique elec-trical properties and quantum phenomena,making them attractive for advanced electronic applications.However,large-scale ... Quasi-one-dimensional(quasi-1D)van der Waals(vdWs)materials,such as ZrTe_(5),exhibit unique elec-trical properties and quantum phenomena,making them attractive for advanced electronic applications.However,large-scale growth of ZrTe_(5) thin films presents challenges.We address this by employing sput-tering,a common semiconductor industry technique.The as-deposited ZrTe_(5) film is amorphous,and post-annealing induces a crystallization process akin to transition-metal dichalcogenides.Our study in-vestigates the electrical and optical properties during this amorphous-to-crystalline transition,reveal-ing insights into the underlying mechanism.This work contributes to the fundamental understanding of quasi-1D materials and introduces a scalable fabrication method for ZrTe_(5) which offers the possibility of fabricating unique future electronic and optical devices. 展开更多
关键词 QUASI-ONE-DIMENSIONAL ZrTe_(5) Large-scale Thin film PHASE-CHANGE
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Locally-doped MoS_(2) monolayer with in-plane bifunctional heterostructure toward overall water splitting
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作者 Zhuo-Jun Duan Hang Xia +10 位作者 Han-Ze Li Gong-Lei Shao Yi-Zhang Ren Xuan Tang Qiu-Nan Liu Jin-Hua Hong Sheng Dai Yung-Chang Lin Kazu Suenaga Yong-Min He Song Liu 《Rare Metals》 2025年第5期3130-3140,共11页
Exploring earth-abundant,highly active bifunctional electrocatalysts for efficient hydrogen and oxygen evolution is crucial for water splitting.However,due to their distinct free energies and conducting behaviors(elec... Exploring earth-abundant,highly active bifunctional electrocatalysts for efficient hydrogen and oxygen evolution is crucial for water splitting.However,due to their distinct free energies and conducting behaviors(electron/hole),balancing the catalytic efficiency between hydrogen and oxygen evolution remains challenging for achieving bifunctional electrocatalysts.Here,we report a locally-doped MoS_(2)monolayer with an in-plane heterostructure acting as a bifunctional electrocatalyst and apply it to the overall water splitting.In this heterostructure,the core region contains Mo/S vacancies,while the ring region was doped by Fe atoms(in two substitution configurations:1FeMo and 3FeMo-VS clusters)with a p-type conductive characteristic.Our micro-cell measurements,combined with density functional theory(DFT)calculations,reveal that the vacancies-rich core region presents remarkable hydrogen evolution reaction(HER)activity while the Fe-doped ring gives an excellent oxygen evolution reaction(OER)activity,thus forming an in-plane bifunctional electrocatalyst.Finally,as a proof-of-concept for overall water splitting,we constructed a full-cell configuration based on a locally-doped MoS_(2)monolayer,which achieved a cell voltage of 1.87 V at 10 mA·cm^(-2),demonstrating outstanding performance in strong acid electrolytes.Our work provides insight into the hetero-integration of bifunctional electrocatalysts at the atomic level,paving the way for designing transition metal dichalcogenide catalysts with activity-manipulated regions capable of multiple reactions. 展开更多
关键词 Locally-doped monolayer In-plane heterostructure MoS_(2) Bifunctional catalysts Overall water salitting
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A Hybrid CNN-Transformer Framework for Normal Blood Cell Classification:Towards Automated Hematological Analysis
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作者 Osama M.Alshehri Ahmad Shaf +7 位作者 Muhammad Irfan Mohammed M.Jalal Malik A.Altayar Mohammed H.Abu-Alghayth Humood Al Shmrany Tariq Ali Toufique A.Soomro Ali G.Alkhathami 《Computer Modeling in Engineering & Sciences》 2025年第7期1165-1196,共32页
Background:Accurate classification of normal blood cells is a critical foundation for automated hematological analysis,including the detection of pathological conditions like leukemia.While convolutional neural networ... Background:Accurate classification of normal blood cells is a critical foundation for automated hematological analysis,including the detection of pathological conditions like leukemia.While convolutional neural networks(CNNs)excel in local feature extraction,their ability to capture global contextual relationships in complex cellular morphologies is limited.This study introduces a hybrid CNN-Transformer framework to enhance normal blood cell classification,laying the groundwork for future leukemia diagnostics.Methods:The proposed architecture integrates pre-trained CNNs(ResNet50,EfficientNetB3,InceptionV3,CustomCNN)with Vision Transformer(ViT)layers to combine local and global feature modeling.Four hybrid models were evaluated on the publicly available Blood Cell Images dataset from Kaggle,comprising 17,092 annotated normal blood cell images across eight classes.The models were trained using transfer learning,fine-tuning,and computational optimizations,including cross-model parameter sharing to reduce redundancy by reusing weights across CNN backbones and attention-guided layer pruning to eliminate low-contribution layers based on attention scores,improving efficiency without sacrificing accuracy.Results:The InceptionV3-ViT model achieved a weighted accuracy of 97.66%(accounting for class imbalance by weighting each class’s contribution),a macro F1-score of 0.98,and a ROC-AUC of 0.998.The framework excelled in distinguishing morphologically similar cell types demonstrating robustness and reliable calibration(ECE of 0.019).The framework addresses generalization challenges,including class imbalance and morphological similarities,ensuring robust performance across diverse cell types.Conclusion:The hybrid CNN-Transformer framework significantly improves normal blood cell classification by capturing multi-scale features and long-range dependencies.Its high accuracy,efficiency,and generalization position it as a strong baseline for automated hematological analysis,with potential for extension to leukemia subtype classification through future validation on pathological samples. 展开更多
关键词 Acute leukemia automated diagnosis blood cell classification convolution neural networks deep learning fine-tuning hematologic malignancy hybrid deep learning architecture leukemia subtype classification medical image analysis transfer learning vision transformers
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2019年四川威远东两次M_(S)>5.0地震序列活动特征及震源区体波速度结构 被引量:2
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作者 张栓 江国焰 +3 位作者 许才军 雷兴林 苏金蓉 林学楷 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第1期128-143,共16页
自2015年以来,四川威远及邻区的地震活动强度显著增强,其中2019年9月8日和12月18日在威远东发生了M_(S)5.4和M_(S)5.2地震,刷新了威远地区有记录以来历史地震震级上限.本文利用2019年8月至2020年3月期间威远及邻区25个流动台和17个固定... 自2015年以来,四川威远及邻区的地震活动强度显著增强,其中2019年9月8日和12月18日在威远东发生了M_(S)5.4和M_(S)5.2地震,刷新了威远地区有记录以来历史地震震级上限.本文利用2019年8月至2020年3月期间威远及邻区25个流动台和17个固定台记录到的5638次M_(L)≥1.2地震Pg和Sg波到时以及连续波形资料,采用双差层析成像方法获得了威远东这两次地震序列的重定位结果和震源区浅层地壳高分辨率三维体波速度结构.重定位结果显示震源区地震震源深度主要集中在3~4 km.基于两次M_(S)>5.0地震震后10天余震序列空间展布,本文推测两次地震的发震构造均为NNE走向且倾向SE(倾角40°左右)的盲冲断层.三维体波速度结构反演结果揭示:震源区V_(P)异常变化较V_(S)异常变化显著,V_(P)/V_(S)比背景值普遍低4%~10%.在深度小于5 km的浅层内,地震多分布在V_(P)低速异常和V_(S)弱高速异常以及二者的高低速异常过渡带内;在5~7 km深度范围,地震基本上都发生在V_(P)低速异常区.上述速度结构特征揭示震源区附近可能发育着富含气体的孔隙和裂缝且存在流体活动.此外,2019年11月7日以后的地震活动具有明显的流体扩散驱动地震迁移特征,沿两次地震发震断层走向和倾向的流体扩散系数分别为1.5 m~2·s^(-1)和0.1 m~2·s^(-1).两次地震的发生机理很可能是流体扩散引起的孔隙压力上升. 展开更多
关键词 四川威远东 M_(S)>5.0地震 双差层析成像 地震活动特征 体波速度结构
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Step-over of strike-slip faults and overpressure fluid favor occurrence of foreshocks:Insights from the 1975 Haicheng fore-main-aftershock sequence,China 被引量:7
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作者 Xinglin Lei Zhiwei Wang +1 位作者 Shengli Ma Changrong He 《Earthquake Research Advances》 CSCD 2024年第1期36-46,共11页
This study analyzed and summarized in detail the spatial and temporal distributions of earthquakes,tidal responses,focal mechanisms,and stress field characteristics for the M 7.3 Haicheng earthquake sequence in Februa... This study analyzed and summarized in detail the spatial and temporal distributions of earthquakes,tidal responses,focal mechanisms,and stress field characteristics for the M 7.3 Haicheng earthquake sequence in February 1975.The foreshocks are related to the main fault and the conjugate faults surrounding the extension step-over in the middle.The initiation timing of the foreshock clusters and the original time of the mainshock were clearly modulated by the Earth's tidal force and coincided with the peak of dilational volumetric tidal strain.As a plausible and testable hypothesis,we proposed a fluid-driven foreshock model,by which all observed seismicity features can be more reasonably interpreted with respect to the results of existing models.Together with some other known examples,the widely existing step-over along strike-slip faults and associated conjugate faults,especially for extensional ones in the presence of deep fluids,favor the occurrence of short-term foreshocks.Although clustered seismicity with characteristics similar to those of the studied case is not a sufficient and necessary condition for large earthquakes to occur under similar tectonic conditions,it undoubtedly has a warning significance for the criticality of the main fault.Subsequent testing would require quantification of true/false positives/negatives. 展开更多
关键词 Haicheng earthquake Seismogenic fault ETAS FORESHOCK Deep fluid
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Mechanism of reduction-diffusion reaction in Sm-Fe binary system at low temperature using molten salts 被引量:1
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作者 Jungryang Kim Shusuke Okada +1 位作者 Kenta Takagi Kimihiro Ozaki 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第10期1889-1894,共6页
In this study,the mechanism of the reduction-diffusion reaction in a Sm-Fe binary system at low temperature was studied to investigate the possibility of synthesis of a Fe-rich TbCu_(7)-type SmFe_(x)(x>9)by the low... In this study,the mechanism of the reduction-diffusion reaction in a Sm-Fe binary system at low temperature was studied to investigate the possibility of synthesis of a Fe-rich TbCu_(7)-type SmFe_(x)(x>9)by the low-temperature diffusion-reduction(LTRD)process using LiCl-KCl eutectic molten salts.Firstly,the Sm-Fe phase transformation depending on the Sm-Fe composition,the LTRD temperature,and time was investigated,and it is found that the obtained metastable phase is only TbCu_(7)-type SmFe_(~8.5),which is not a Fe-rich phase.This Fe content does not change even after an expended LTRD process,and the metastable TbCu_(7)-type SmFe_(~8.5)tends to transform to the stable Sm_(2)Fe_(17)phase.In addition,it is found that the Sm-Fe phase starts to synthesize from the Sm-rich phase in the order of SmFe_(2),SmFe_(3),and SmFe_(8.5)as the LTRD temperature increases(when the time was 10 h)or the LTRD time increases(when the temperature was 550℃).Core-shell-like particles are observed in the case of a short LTRD time,and the core and the shell are Fe and the Sm-rich Sm-Fe phase,respectively,indicating that the Sm-rich phase begins to produce on the surface of the Fe particles.It is difficult to synthesize a Fe-rich TbCu_(7)-type SmFe_(x)(x>9)phase with the Sm-Fe binary system,suggesting that a different approach,such as addition of other elements,will be necessary. 展开更多
关键词 Low-temperature synthesis Synthesis mechanism Reduction-diffusion process Molten salts Sm-Fe compounds Rare earths
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经下皱襞切口假体隆乳术矫正小乳症及乳腺萎缩 被引量:1
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作者 王谊 杨千里 +2 位作者 陈翔宇 陈清湘 邓旭辉 《中国美容医学》 CAS 2024年第6期18-21,共4页
目的:探究经下皱襞切口假体隆乳术矫正小乳症或乳腺萎缩的临床疗效及并发症发生率。方法:选取2021年01月-2022年12月笔者医院收治的97例行经下皱襞切口假体隆乳术的小乳症或乳腺萎缩就医者临床资料进行回顾性分析。所有就医者术中使用... 目的:探究经下皱襞切口假体隆乳术矫正小乳症或乳腺萎缩的临床疗效及并发症发生率。方法:选取2021年01月-2022年12月笔者医院收治的97例行经下皱襞切口假体隆乳术的小乳症或乳腺萎缩就医者临床资料进行回顾性分析。所有就医者术中使用超声刀精准剥离双平面腔隙后使用一次性隆乳手术用漏斗置入假体,并予以精细化超减张缝合切口。术后,总结分析临床疗效和并发症。结果:本组97例就医者共置入194只硅凝胶假体,单侧假体平均体积(252.73±3.53)ml,手术时间(99.41±9.35)min,术后引流量(44.00±6.84)ml,术后疼痛VAS评分第1天(3.08±0.83)分、第2天(1.95±0.76)分、出院时(1.62±0.69)分,住院时间(2.51±0.75)d。术后随访6~24个月,所有就医者均表示术后乳房形态饱满、柔软度较佳、切口瘢痕隐藏化。JY-Breast-Q量表评价结果显示,手术增加了就医者自信,提高了就医者的生活质量。结论:经乳房下皱襞切口矫正小乳症或乳腺萎缩具有手术路径短,操作简单、术野直视、创伤小、术后康复快及并发症发生率低的优势。 展开更多
关键词 假体隆乳术 下皱襞 小乳症 乳腺萎缩 并发症
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Hydro-mechanical-electrical simulations of synthetic faults in two orthogonal directions with shear-induced anisotropy
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作者 Kazuki Sawayama Takuya Ishibashi +1 位作者 Fei Jiang Takeshi Tsuji 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4428-4439,共12页
Fluid flow in fractures controls subsurface heat and mass transport,which is essential for developing enhanced geothermal systems and radioactive waste disposal.Fracture permeability is controlled by fracture microstr... Fluid flow in fractures controls subsurface heat and mass transport,which is essential for developing enhanced geothermal systems and radioactive waste disposal.Fracture permeability is controlled by fracture microstructure(e.g.aperture,roughness,and tortuosity),but in situ values and their anisotropy have not yet been estimated.Recent advances in geophysical techniques allow the detection of changes in electrical conductivity due to changes in crustal stress and these techniques can be used to predict subsurface fluid flow.However,the paucity of data on fractured rocks hinders the quantitative interpretation of geophysical monitoring data in the field.Therefore,considering different shear displacements and chemical erosions,an investigation was conducted into the hydraulic-electric relationship as an elevated stress change in fractures.The simulation of fracture flows was achieved using the lattice Boltzmann method,while the electrical properties were calculated through the finite element method,based on synthetic faults incorporating elastic-plastic deformation.Numerical results show that the hydraulic and electrical properties depend on the rock's geometric properties(i.e.fracture length,roughness,and shear displacement).The permeability anisotropy in the direction parallel or perpendicular to the shear displacement is also notable in high stress conditions.Conversely,the permeability econductivity(i.e.,formation factor)relationship is unique under all conditions and follows a linear trend in logarithmic coordinates.However,both matrix porosity and fracture spacing alter this relationship.Both increase the slope of the linear trend,thereby changing the sensitivity of electrical observations to permeability changes. 展开更多
关键词 Fracture flow Permeability Electrical conductivity Lattice Boltzmann method ANISOTROPY Chemical erosion Enhanced geothermal system
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Optimizing Bearing Fault Detection:CNN-LSTM with Attentive TabNet for Electric Motor Systems
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作者 Alaa U.Khawaja Ahmad Shaf +4 位作者 Faisal Al Thobiani Tariq Ali Muhammad Irfan Aqib Rehman Pirzada Unza Shahkeel 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第12期2399-2420,共22页
Electric motor-driven systems are core components across industries,yet they’re susceptible to bearing faults.Manual fault diagnosis poses safety risks and economic instability,necessitating an automated approach.Thi... Electric motor-driven systems are core components across industries,yet they’re susceptible to bearing faults.Manual fault diagnosis poses safety risks and economic instability,necessitating an automated approach.This study proposes FTCNNLSTM(Fine-Tuned TabNet Convolutional Neural Network Long Short-Term Memory),an algorithm combining Convolutional Neural Networks,Long Short-Term Memory Networks,and Attentive Interpretable Tabular Learning.The model preprocesses the CWRU(Case Western Reserve University)bearing dataset using segmentation,normalization,feature scaling,and label encoding.Its architecture comprises multiple 1D Convolutional layers,batch normalization,max-pooling,and LSTM blocks with dropout,followed by batch normalization,dense layers,and appropriate activation and loss functions.Fine-tuning techniques prevent over-fitting.Evaluations were conducted on 10 fault classes from the CWRU dataset.FTCNNLSTM was benchmarked against four approaches:CNN,LSTM,CNN-LSTM with random forest,and CNN-LSTM with gradient boosting,all using 460 instances.The FTCNNLSTM model,augmented with TabNet,achieved 96%accuracy,outperforming other methods.This establishes it as a reliable and effective approach for automating bearing fault detection in electric motor-driven systems. 展开更多
关键词 Electric motor-driven systems bearing faults AUTOMATION fine tunned convolutional neural network long short-term memory fault detection
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Assessing the Ethnobotanical Uses, Harvesting Practices, and Conservation Awareness of Warburgia ugandensis in Northern Tanzania
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作者 Letan K. Mollel Linus K. Munishi Richard A. Giliba 《Open Journal of Ecology》 2024年第12期924-937,共14页
Warburgia ugandensis is unsustainably harvested commercially, threatening its survival and potentially leading to local extinction in its native range areas in Northern Tanzania. Our study aimed to assess the extent o... Warburgia ugandensis is unsustainably harvested commercially, threatening its survival and potentially leading to local extinction in its native range areas in Northern Tanzania. Our study aimed to assess the extent of harvesting of W. ugandensis in Northern Tanzania, ethno-botanical uses, community perceptions of species utilization, and conservation measures across its native range in Northern Tanzania. From each of the 128 randomly selected grids, we laid down a sampling plot measuring 100 m × 100 m (1 ha) for the identification, and collection of data on the extent of harvesting of W. ugandensis. Additionally, we interviewed 221 respondents using open-ended questionnaires to gather data on ethno-botanical uses, perceptions of product utilization, and conservation measures. We analyzed the data using descriptive statistics and Kruskal-Wallis tests. Our findings reveal significant variation in the extent of harvesting, with Mt. Ketumbeine experiencing the most severe harvesting while Mt. Kilimanjaro holds the highest number of intact trees. Community knowledge of the medicinal uses of W. ugandensis was highest in Mt. Kilimanjaro, particularly for treating gastrointestinal disorders, coughs, and malaria. Perceptions of species utilization were very high in Mt. Gelai and Mt. Monduli, while Mt. Kilimanjaro, Ketumbeine, and Longido showed more variability. Awareness of W. ugandensis conservation measures was high in Mt. Kilimanjaro, compared to the rest of the species’ native range areas. Therefore, our study findings underscore the urgent need for targeted conservation initiatives, particularly in regions like Mt. Ketumbeine and Mt. Longido, where W. ugandensis faces the severe extent of harvesting. 展开更多
关键词 Warburgia ugandensis ETHNOBOTANY Sustainable Harvesting Conservation Awareness Medicinal Plants Northern Tanzania
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Is platinum-loaded titania the best material for dye-sensitized hydrogen evolution under visible light?
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作者 Haruka Yamamoto Langqiu Xiao +5 位作者 Yugo Miseki Hiroto Ueki Megumi Okazaki Kazuhiro Sayama Thomas E.Mallouk Kazuhiko Maeda 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期124-132,共9页
A dye-sensitized photocatalyst combining Pt-loaded TiO_(2) and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)N... A dye-sensitized photocatalyst combining Pt-loaded TiO_(2) and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)Nb_(3)O_(10) nanosheets.When the sacrificial donor ethylenediaminetetraacetic acid(EDTA)disodium salt dihydrate was used,RuP/Pt/TiO_(2) showed higher activity than RuP/Pt/HCa_(2)Nb_(3)O_(10).In contrast,when NaI(a reversible electron donor)was used,RuP/Pt/TiO_(2) showed little activity due to back electron transfer to the electron acceptor(I_(3)-),which was gener-ated as the oxidation product of I-.By modification with anionic polymers(sodium poly(styrenesulfonate)or sodium polymethacrylate)that could inhibit the scavenging of conduction band electrons by I_(3)-,the H_(2) production activity from aqueous NaI was improved,but it did not exceed that of RuP/Pt/HCa_(2)Nb_(3)O_(10).Transient absorption measurements showed that the rate of semiconductor-to-dye back electron transfer was slower in the case of TiO_(2) than HCa_(2)Nb_(3)O_(10),but the electron transfer reaction to I3-was much faster.These results indicate that Pt/TiO_(2) is useful for reactions with sacrificial reductants(e.g.,EDTA),where the back electron transfer reaction to the more reducible product can be neglected.However,more careful design of the catalyst will be nec-essary when a reversible electron donor is employed. 展开更多
关键词 Artificial photosynthesis Solar fuel Water splitting Z-scheme
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二维纳米材料MXene的研究进展 被引量:38
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作者 郑伟 孙正明 +3 位作者 张培根 田无边 王英 张亚梅 《材料导报》 EI CAS CSCD 北大核心 2017年第9期1-14,共14页
MXene是一类新型碳/氮化物二维纳米层状材料,一般是利用化学刻蚀的手段通过选择性刻蚀掉前驱体MAX相中的A原子层而得到。其通式可表示为M_(n+1)X_nT_x,其中M代表早期过渡族金属,X代表碳和/或氮,T_x代表MXene在刻蚀过程中产生的附着在其... MXene是一类新型碳/氮化物二维纳米层状材料,一般是利用化学刻蚀的手段通过选择性刻蚀掉前驱体MAX相中的A原子层而得到。其通式可表示为M_(n+1)X_nT_x,其中M代表早期过渡族金属,X代表碳和/或氮,T_x代表MXene在刻蚀过程中产生的附着在其表面的官能团(-OH、-F、=O、等)。采用一定的手段将多层MXene剥落,可获得类石墨烯形貌的单层MXene。MXene除了具备传统二维材料的性能外,还兼具良好的导电性、亲水性、透光性、柔韧性以及能量储存性能,在复合材料、润滑剂、环境污染治理、电池、电容器、催化、传感器、抗菌等领域具有潜在的应用价值。文章总结了MXene的制备、结构、性能和应用等方面的最新成果,并展望了其今后的研究方向。 展开更多
关键词 MAX相 MXene 二维材料 刻蚀 制备 应用
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关于2021年5月滇西漾濞M_(S)6.4地震序列特征及成因的初步研究 被引量:57
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作者 雷兴林 王志伟 +1 位作者 马胜利 何昌荣 《地震学报》 CSCD 北大核心 2021年第3期261-286,I0001,共27页
2021年5月21日21时48分在滇西苍山西麓漾濞地区发生M_(S)6.4(MW6.1)强震,相关地震活动表现为一个典型的前震-主震-余震序列。本研究分别就该地震序列的构造背景、M1.0以上地震的双差定位、主要地震的矩张量反演和破裂传播方向、应力场... 2021年5月21日21时48分在滇西苍山西麓漾濞地区发生M_(S)6.4(MW6.1)强震,相关地震活动表现为一个典型的前震-主震-余震序列。本研究分别就该地震序列的构造背景、M1.0以上地震的双差定位、主要地震的矩张量反演和破裂传播方向、应力场反演及断层滑动趋势以及潮汐作用等方面进行了初步分析。矩张量反演结果表明,矩心深度为6.0 km。根据断层破裂传播方向分析结果及精定位余震分布判定,主震震源断层产状为走向137°,倾角75°,滑动角-167°,破裂沿南东向单侧扩展,右旋走滑含正断层分量。漾濞地震序列发生在红河断裂带北段延伸方向上的乔后—巍山断裂附近,但主震震源断层及主要余震的分布在走向和位置上均明显偏离已知的乔后—巍山断裂。地震序列受一个发育程度不高、含多级雁列构造的北西向为主、北东向为次的共轭走滑断层系统(本文称为"漾濞断层")所控制,整体上沿北西向断层展布,主震与部分强余震为北西向断层活动所致,但中强前震和多数余震为北东向断层活动所致。中强震的断层破裂均为单侧扩展,北西向断层主要表现为南东向破裂扩展,而北东向断层沿两个方向破裂扩展,相邻地震还存在往返破裂现象。对截至5月23日所发生的M>4.0前震和余震进行了全矩张量反演。利用漾濞地震震中15 km范围内20多个MW>3.4余震的比较可靠的震源机制解反演了该区的应力场,结果显示:主应力形状比φ=(σ_(2)-σ_(3))/(σ_(1)-σ_(3))为0.46±0.17;最大主应力轴的方位角为188.0°±9.0°,倾伏角为12.4°±7.0°;中间主应力轴近直立,倾伏角为72.1°±11.3°;最小主应力轴的方位角为280.3°±7.0°,倾伏角为10.4°±12.0°。本文还对理论潮汐应变及应力进行了分析,结果表明,该地震序列受潮汐调制作用十分明显。5月18日18时及19日20时开始的两组前震群的首个主要地震以及5月21日晚发生的主震均发生在潮汐体应变和库仑应力的峰值附近,余震活动也与潮汐有明显的相关性。综合主要地震震源机制解、前震及余震分布、潮汐调制特征、基于应力场反演的断层滑动趋势分析以及滇西北地区以往类似地震活动研究结果,本文初步推断:漾濞地震受深部流体作用的影响明显,5月18日18时开始的第一次前震活动高潮从北西向断层的一个拉张性断层阶区开始,最大前震的震源断层为北东向断层,随后向北西方向迁移;19日20时开始的第二次前震活动高潮集中在主震震源附近。这些地震的触发及深部流体作用共同促进了北西向断层的活动,但主震的发生受深部流体作用为主。 展开更多
关键词 矩张量反演 应力场反演 前震 破裂方向性 滑动趋势 地下流体 潮汐调制
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Mo基分子筛催化剂及甲烷无氧芳构化 被引量:12
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作者 胥月兵 陆江银 +1 位作者 王吉德 张战国 《化学进展》 SCIE CAS CSCD 北大核心 2011年第1期90-106,共17页
本文综述了甲烷无氧芳构化反应及Mo基分子筛催化剂的研究进展。在众多的催化剂中以Mo基分子筛催化性能最佳。概括了催化剂中关于MoOx前躯体结构和其在分子筛中落位,Mo2C物种和诱导期等;讨论了反应中涉及的中间产物、双功能机理以及催化... 本文综述了甲烷无氧芳构化反应及Mo基分子筛催化剂的研究进展。在众多的催化剂中以Mo基分子筛催化性能最佳。概括了催化剂中关于MoOx前躯体结构和其在分子筛中落位,Mo2C物种和诱导期等;讨论了反应中涉及的中间产物、双功能机理以及催化剂失活等问题;归纳了催化剂制备过程中制备方法、焙烧温度与时间、Mo载量和分子筛硅铝比以及催化剂预处理对反应活性的影响;综述了提高催化剂催化性能和反应性能的各种方法,并对其分析,同时介绍了两种催化剂再生方法。最后,依据本实验室研究进展,对甲烷芳构化从工艺角度进行一些可行性讨论,并提出相关问题和展望。 展开更多
关键词 甲烷 无氧芳构化 芳烃 Mo基催化剂
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