检索结果-内蒙古大学图书馆

Alkali ions substitution induced tuning of sensitivity in mixed-valence europium ion co-doped NaZr₂(PO₄)₃ thermochromic phosphor for optical thermometry

引用

JOURNAL OF ALLOYS AND COMPOUNDS 2021年 865卷 158820-158820页

作者： Liu, fuwen Deng, Degang Wu, Ming chen, Bowen Zhou, Liuyan Xu, Shiqing China Jiliang Univ Inst Optoelect Mat & Devices Hangzhou 310018 Peoples R China

Developing a new temperature sensing material with high temperature sensitivity and resolution is crucial in optical thermometry. Therefore, a series of dual-emitting Eu2+/Eu3+ co-doped NaZr2(PO4)(3) phosphors were prepared in the air atmosphere. Eu3+ ions successfully replaced Na' and were partially reduced to Eu 2 '. Then, the K' ions were introduced to replace Na' ions, which affected the luminescence and thermostability of Eu2+ and Eu3+. The reducing mechanism and the effect of Eu doping concentration on the Eu3+/Eu2+ reduction ratio were discussed in detail. Using different responses of Eu2+ and Eu3+ to the changing temperature, the FIR (fluorescence intensity ratio) signals were detected to measure temperature (293-413 K). The K+ ions influence the crystalline field and energy level structure, thereby decreasing the thermal stability of Eu2+ and enhancing that of Eu3+, resulting in the improvement of S-a and S-r to 0.026 K-1 and 3.84% K-1, respectively. Its temperature sensitivity is higher than that of many other reported inorganic materials, demonstrating that the NaZr2(PO4)(3): Eu phosphors have a good application prospect in optical thermometry. (C) 2021 Elsevier B.V. All rights reserved.

关键词： NaZr2(PO4)(3) FIR Optical thermometry Sensitivity tuning

来源：评论

学校读者我要写书评

暂无评论

轻量化无人机航拍目标检测算法

引用

电子测量技术 2022年第19期45卷 167-174页

作者：王恒涛张上陈想贾付文三峡大学湖北省建筑质量检测装备工程技术研究中心宜昌443002 三峡大学计算机与信息学院宜昌443002

针对无人机航拍背景复杂、检测目标小且密集。提出一种基于YOLOv5的轻量化无人机航拍目标检测算法SDS-YOLO。首先,SDS-YOLO算法重构轻量化网络结构,对特征提取网络和特征融合网络进行重构。调节检测层和感受野架构,建立深层语义与浅层... 详细信息

针对无人机航拍背景复杂、检测目标小且密集。提出一种基于YOLOv5的轻量化无人机航拍目标检测算法SDS-YOLO。首先,SDS-YOLO算法重构轻量化网络结构,对特征提取网络和特征融合网络进行重构。调节检测层和感受野架构,建立深层语义与浅层语义多尺度检测信息依赖关系,增加浅层网络特征层的权重,提高对微小目标的检测能力;其次,利用聚类算法对预选框进行调整,实现重构网络最优的预选框选择机制,加快模型收敛速度。最后,使用Varifocal loss训练SDS-YOLO使IACS回归,提高模型对密集物体的检测能力。结果表明,模型经过优化后,精度提高了7.64%;模型体积4.25 MB,相较于原模型大幅下降;模型计算量和推理速度均有提高。相较于当前主流算法,SDS-YOLO在各方面均取得了不错的改进,满足无人机航拍实时目标检测要求。

关键词：目标检测多尺度融合模型轻量化 YOLOv5 Varifocal loss

来源：评论

学校读者我要写书评

暂无评论

RSL1D1 modulates cell senescence and proliferation via regulation of PPAR? mRNA stability

引用

LIFE SCIENCES 2022年第0期307卷 000-000页

作者： Jiang, Zhe Hao, Fengxin Zhu, Feng Yuan, fuwen Ma, Liwei Li, Guodong chen, Jun Tong, Tanjun Peking Univ Res Ctr Aging Sch Basic Med Sci Dept Biochem & Mol BiolHlth Sci CtrBeijing Key L Beijing Peoples R China Sanofi Beijing Pharmaceut Co Ltd Beijing Peoples R China Shanghai Univ Tradit Chinese Med Acad Integrat Med Shanghai Peoples R China

Aims: In this study, we will examine if RSL1D1 influences PPAR gamma expression and explore the underlying mechanism that RSL1D1 regulates PPAR gamma expression. Moreover, the significance of RSL1D1-PPAR gamma pathway in cell senescence and proliferation will also be determined. Main methods: Our main methods include western blotting, immunoprecipitation (IP), real-time PCR, RNA Immunoprecipitation (RIP), biotin-labeled RNA pull down assay, dual luciferase reporter gene assay, senescence -associated beta-galactosidase staining, cell proliferation assay, colony formation assay, wound healing assay, blood biochemistry test and Oil red O staining. Key findings: By analyzing gene chip results we find that the expression of RSL1D1 and PPAR gamma might be corre-lated. Then we show that RSL1D1 is a posttranscriptional regulator of PPAR gamma. RSL1D1 overexpression elevates, while RSL1D1 knockdown inhibits, PPAR gamma mRNA and protein expression levels. Mechanistically, we find that RSL1D1 directly interacts with the 3'-untranslated region of PPAR gamma mRNA, and then promotes its stability and increases PPAR gamma protein expression level. We further demonstrate that RSL1D1 modulates cellular senescence and cell proliferation partially via PPAR gamma-regulated downstream target genes such as PTEN/p27, NF-kappa B, GLUT4, and ACL. Moreover, we find that RSL1D1 regulates PPAR gamma expression and function in a HuR-dependent manner. Last, we show that RSL1D1 knockout in mouse adipose tissue shortens mouse lifespan and leads to hepatic damage which may impair liver damage repair function. Significance: Collectively, our findings unveil a novel posttranscriptional regulation of PPAR gamma by RSL1D1 and uncover a critical role of RSL1D1-PPAR gamma-PPAR gamma downstream target genes in regulating cellular senescence and cell proliferation.

关键词： CSIG PPAR ? HuR Cell senescence Post transcriptional regulation

来源：评论

学校读者我要写书评

暂无评论

锂硫电池的电解质安全性的研究进展及军事化前景

引用

兵器材料科学与工程 2025年第1期48卷 145-154页

作者：陈建安陈曦 POTAPENKO Hanna 郭珉李怡郝慧敏李昕钰聂泽龙祝付文中国兵器科学研究院宁波分院浙江宁波315103 山东三品新能源有限公司山东济宁272342 山西风雷钻具有限公司山西临汾043000

锂硫电池凭借其高能量密度和成本优势,在无人驾驶飞行器、地面车辆和海洋无人驾驶船舶等军事领域展现出巨大的潜力。然而,锂硫电池用易燃的硫正极、高活泼的锂负极及低闪点、低沸点的有机电解液会产生严重的安全隐患,导致其军用化面临... 详细信息

锂硫电池凭借其高能量密度和成本优势,在无人驾驶飞行器、地面车辆和海洋无人驾驶船舶等军事领域展现出巨大的潜力。然而,锂硫电池用易燃的硫正极、高活泼的锂负极及低闪点、低沸点的有机电解液会产生严重的安全隐患,导致其军用化面临困境。为了解决这些问题,研究者通过开发新型电解质、优化负极材料、改性隔膜和改进正极材料等提高电池的安全性。在这些方法中,电解质是提高安全性的最关键要素。特别是近年来固态电解质的兴起,使针对电解质的研究更具重要意义。本文综述了锂硫电池电解质安全性提升策略的研究现状,并展望了未来的研究方向。

关键词：锂硫电池安全性阻燃剂液态电解质固态电解质

来源：评论

学校读者我要写书评

暂无评论

Study on the mechanism and pharmacokinetics of HB-NC4 based on C5b-9 target in the treatment of osteoarthritis

引用

BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR BASIS OF DISEASE 2023年第5期1869卷 166699页

作者： Chai, Rongrong Yu, Xueting Li, Lian Wei, Qiang Jiao, Guangjun Li, Ying Yu, chen Mu, Yanling Yao, Qingqiang Li, Yan Wang, fuwen Shandong First Med Univ Sch Pharm & Pharmaceut Sci Jinan 250117 Shandong Peoples R China Shandong Acad Med Sci NHC Key Lab biotechnol drugs Key Lab Rare & Uncommon Dis Shandong Prov Jinan 250117 Shandong Peoples R China Shandong Univ Cheeloo Coll Med Sch Pharmaceut Sci Jinan 250012 Shandong Peoples R China Tangshan Normal Univ Dept Phys Educ Tangshan 063000 Hebei Peoples R China Shandong Univ Qilu Hosp Jinan 250012 Shandong Peoples R China

Osteoarthritis (OA) is a chronic degenerative disease that mostly occurs in elderly individuals over 60 years old. The detailed pathogenesis of OA is unclear. Medicines available on the market are nonsteroidal antiinflammatory drugs. Therefore, in this study, a fusion protein was introduced, and the detailed mechanism that could alleviate OA was discussed. As a targeted protein, HB-NC4 showed better binding ability to chondrocytes, and its half-life period was prolonged compared to NC4 alone. In addition, HB-NC4 can not only affect the levels of C3 and C5, but also inhibit the formation of the membrane-attack complex (MAC, C5b-9), thereby further affecting the expression of MAPK signalling pathway-related proteins to achieve the goal of treating OA. Thus, in this study, we demonstrate the pharmacokinetics of HB-NC4 and its mechanism to alleviate OA by regulating the complement system and MAPK signalling pathway. This study provides a new method for OA therapy based on fusion proteins.

关键词： Osteoarthritis C5b-9 Fusion protein Complement system

来源：评论

学校读者我要写书评

暂无评论

Genomic evidence for low genetic diversity but purging of strong deleterious variants in snow leopards

引用

GENOME BIOLOGY 2025年第1期26卷 1-24页

作者： Yang, Lin Jin, Hong Yang, Qien Poyarkov, Andrey Korablev, Miroslav Rozhnov, Viatcheslav Shao, Junjie Fu, Qiaomei Hernandez-Blanco, Jose Antonio Zhan, Xiangjiang Yu, Li Alexandrov, Dmitry Dai, Qingyan Munkhtsog, Bariushaa Du, Xin Munkhtsog, Bayaraa Ma, Liqing chen, Wanlin Malykh, Sergei Jin, Yipeng He, Shunfu Zhang, Tongzuo Wu, Guosheng Shi, Yonghong Wei, fuwen Hu, Yibo Chinese Acad Sci Inst Zool CAS Key Lab Anim Ecol & Conservat Biol Beijing Peoples R China Jiangxi Agr Univ Coll Forestry Jiangxi Key Lab Conservat Biol Nanchang Jiangxi Peoples R China Southern Marine Sci & Engn Ctr Evolut & Conservat Biol Guangdong Lab Guangzhou Peoples R China Chinese Acad Sci Northwest Inst Plateau Biol Key Lab Adaptat & Evolut Plateau Biota Xining Qinghai Peoples R China Russian Acad Sci AN Severtsov Inst Ecol & Evolut Moscow Russia Univ Chinese Acad Sci Beijing Peoples R China Chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Key Lab Vertebrate Evolut & Human Origins Beijing Peoples R China Yunnan Univ State Key Lab Conservat & Utilizat Bioresource Kunming 650091 Yunnan Peoples R China Irbis Mongolia Ctr Ulaanbaatar Mongolia Mongolian Acad Sci Inst Biol Ulaanbaatar Mongolia Qinghai Univ Qinghai Acad Anim Sci & Vet Med Qinghai Prov Key Lab Pathogen Diag Anim Dis Xining 810016 Qinghai Peoples R China Qinghai Univ Green Techn Res Prevent & Control Xining Qinghai Peoples R China China Agr Univ Coll Vet Med Clin Dept Beijing Peoples R China Xining Wildlife Zoo Xining Qinghai Peoples R China Golmud Forestry & Grassland Stn Qinghai Prov Haixi 816000 Peoples R China

BackgroundLong-term persistence of species with low genetic diversity is the focus of widespread attention in conservation biology. The snow leopard, Panthera uncia, is a big cat from high-alpine regions of Asia. However, its subspecies taxonomy, evolutionary history, evolutionary potential, and survival strategy remain unclear, which greatly hampers their *** sequence a high-quality chromosome-level genome of the snow leopard and the genomes of 52 wild snow leopards. Population genomics reveal the existence of two large genetic lineages in global snow leopards, the northern and southern lineages, supported by the biogeography. The Last Glacial Maximum drove the divergence of two lineages. Microclimate differences and large rivers between the western and central Himalayas likely maintain the differentiation of two lineages. EPAS1 is positively selected in the southern lineage with almost fixed amino acid substitutions and shows an increased allele frequency with elevation. Compared to the southern lineage, the northern lineage exhibits a lower level of genomic diversity and higher levels of inbreeding and genetic load, consistent with its recent population decline. We find that snow leopards have extremely low genomic diversity and higher inbreeding than other Carnivora species;however, strong deleterious mutations have been effectively purged in snow leopards by historical population bottlenecks and inbreeding, which may be a vital genetic mechanism for their population survival and *** findings reveal the survival strategy of a species with low genetic diversity and highlight the importance of unveiling both genetic diversity and genetic burden for the conservation of threatened species.

关键词： Snow leopards Population genomics Genetic structure Genomic diversity Deleterious variants EPAS1

来源：评论

学校读者我要写书评

暂无评论

Fabrication of high-temperature-resistant bondline based on multilayer core-shell hybrid microspheres for power devices

引用

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS 2019年第4期30卷 3595-3603页

作者： Yu, fuwen chen, Hongtao Hang, Chunjin Li, Mingyu Harbin Inst Technol Mat Sci & Engn Dept Shenzhen 518055 Peoples R China Harbin Inst Technol State Key Lab Adv Welding & Joining Harbin 150001 Heilongjiang Peoples R China

This paper presents a fabrication method for high-temperature-resistant bondlines based on Cu@Ag@Sn multilayer core-shell hybrid microspheres in which a Ag layer was adopted to accelerate the consumption of a Sn layer. The phase transformation and microstructural evolution during the bonding process were investigated in detail. After the microspheres were heated at 250 degrees C for 20min under a pressure of 0.5MPa, the bondline could withstand high operation temperatures of up to 480 degrees C. After reflowing at 250 degrees C for just 5min, the outer low-melting-point Sn layer was completely consumed. After 20min, the bondline was composed of Ag3Sn and Cu3Sn intermetallic compounds with a dispersion of Cu microspheres. The average shear strengths of the resulting bondlines were 39.9 and 31.9MPa at room temperature and at 400 degrees C, respectively.

关键词： Microspheres

来源：评论

学校读者我要写书评

暂无评论

An interconnection method based on Sn-coated Ni core-shell powder preforms for high-temperature applications

引用

JOURNAL OF ALLOYS AND COMPOUNDS 2019年 776卷 791-797页

作者： Yu, fuwen Hang, Chunjin Zhao, Menghui chen, Hongtao Harbin Inst Technol Dept Mat Sci & Technol Shenzhen 518055 Peoples R China Harbin Inst Technol State Key Lab Adv Welding & Joining Harbin 150001 Heilongjiang Peoples R China

A die-attach material based on an Sn-coated Ni core-shell powder with a high re-melting temperature can be used for high-temperature applications. The outer Sn layers of the Sn-coated Ni particles possess a low melting point of 232 degrees C and can be completely converted into a Ni3Sn4 intermetallic compound with a high re-melting point of 794.5 degrees C after reflowing at a low temperature of 250 degrees C for 40 min. This dieattach material exhibits an excellent high-temperature operational capability, with a high shear strength of 40.2 MPa at 500 degrees C. The coefficient of thermal expansion (CTE) of the reflowed preform is between those of SiC and Cu, which is highly beneficial for mitigating the stress caused by the CTE mismatch between these materials. In addition, the thermal conductivity of the bondline is sufficiently high for heat dissipation during operation. (C) 2018 Elsevier B.V. All rights reserved.

关键词： Die attach High re-melting temperature Sn-coated Ni Power devices

来源：评论

学校读者我要写书评

暂无评论

Exploring the Phase Transformation in β-Quenched Ti-55531 Alloy During Continuous Heating via Dilatometric Measurement, Microstructure Characterization, and Diffusion Analysis

引用

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE 2016年第11期47A卷 5383-5394页

作者： chen, fuwen Xu, Guanglong Zhang, Xiaoyong Zhou, Kechao Cent S Univ State Key Lab Powder Met Changsha 410083 Hunan Peoples R China Cent S Univ Sch Mat Sci & Engn Changsha 410083 Hunan Peoples R China

Phase transformations of the beta-quenched Ti-55531 alloy during continuous heating were studied by combining dilatometric measurement with phase analysis, microstructure observation, and local composition mapping. The corresponding transformation sequence can be verified as beta -> omega, beta + omega -> beta + alpha, beta -> alpha, and alpha -> beta. By revisiting the individual phase transformations in the aforementioned transformation sequence, the variations of macro volume discovered in dilatometer test were reinterpreted based on three mechanisms, i.e., modification of crystallographic symmetry, thermodynamically partitioning, and diffusion kinetics. The interplay of different mechanisms was discussed for individual transformations, especially for the combinative partitioning and diffusion kinetic mechanisms of governed alpha a dagger" beta transformation. The pileups of Al atoms behind the growing alpha/beta interface during beta -> alpha and of Mo atoms in the beta side of alpha/beta interface during alpha -> beta were observed and explained by incorporating the diffusion kinetic mechanism. All of these discoveries and discussions provided a deeper understanding of the phase transformations in Ti-55531 alloy.

关键词： Phase transitions

来源：评论

学校读者我要写书评

暂无评论

Residual bond strengths of epoxy and cement-bonded CFRP reinforcements to concrete interfaces after elevated temperature exposure

引用

FIRE SAFETY JOURNAL 2021年 124卷 103393-103393页

作者： Wang, Zhuolin Dai, Jian-Guo Wang, Mingqian chen, Lingzhu Zhang, fuwen Xu, Qingfeng Shanghai Res Inst Bldg Sci Co Ltd Shanghai Key Lab Engn Struct Safety Shanghai 200032 Peoples R China Hong Kong Polytech Univ Dept Civil & Environm Engn Hong Kong Peoples R China

This paper presents the results from a comparative study on the residual bond performance of epoxy and cementbonded carbon fiber-reinforced polymer (CFRP) reinforcement to concrete interfaces that experienced different levels of elevated temperature exposure. In total twelve groups of concrete beams strengthened with CFRP sheet and grids of the same tensile stiffness, through epoxy and cement-based adhesive bonding, respectively, were carefully prepared and exposed to different test temperature levels from 20 degrees C to 600 degrees C. Both polymer cement mortar (PCM) and ductile engineered cementitious composite (ECC) were adopted as the cement binder. The strengthened beams were tested under three-point monotonic bending after different levels of elevated temperature exposure. It was found that with increasing the exposure temperature, the failure modes of the strengthened beams shifted from debonding in a thin layer of concrete substrate to debonding near the fiberadhesive interface and tearing off of CFRP grids from the ECC matrix. The peak loads of concrete beams strengthened with cement-bonded CFRP grids are at least 50% higher than their counterparts strengthened with epoxy-bonded CFRP sheets given the same temperature exposure.

关键词： CFRP reinforcement Concrete Bond behavior Elevated temperature exposure Cement bonding

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：