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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMODULATION Parkinson’s disease primary motor cortex
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Prospects of 3D Printing Technology in Dental Medicine
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作者 Ye Sun 《Journal of Clinical and Nursing Research》 2024年第6期398-403,共6页
With the continuous advancement of technology,the application of 3D printing technology in the field of dental medicine is becoming increasingly widespread.This article aims to explore the current applications and fut... With the continuous advancement of technology,the application of 3D printing technology in the field of dental medicine is becoming increasingly widespread.This article aims to explore the current applications and future potential of 3D printing technology in dental medicine and to analyze its benefits and challenges.It first introduces the current state of 3D printing technology in dental implants,crowns,bridges,orthodontics,and maxillofacial surgery.It then discusses the potential applications of 3D printing technology in oral tissue engineering,drug delivery systems,personalized dental prosthetics,and surgical planning.Finally,it analyzes the benefits of 3D printing technology in dental medicine,such as improving treatment accuracy and patient comfort,and shortening treatment times,while also highlighting the challenges faced,such as costs,material choices,and technical limitations.This article aims to provide a reference for professionals in the field of dental medicine and to promote the further application and development of 3D printing technology in this area. 展开更多
关键词 3D printing technology Dental medicine Dental implants CROWNs Bridges ORTHODONTICs Maxillofacial surgery Tissue engineering Drug delivery systems Personalized dental prosthetics surgical planning
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Codec Negotiation Technologies for 3G 被引量:1
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作者 Chen Yi 1,2Gao Jie 2Yu Li 2(1. Network Division of ZTE Corporation, Nanjing 210012, China 2. Electronics and Information Department, Huazhong University of Science and Technology, Wuhan 430074, China) 《ZTE Communications》 2007年第1期32-36,共5页
The different formats of codec stream carried in the radio access network and the core network make the double speech encoding/decoding necessary, which degrades the speech quality. Accordingly, codec negotiation tech... The different formats of codec stream carried in the radio access network and the core network make the double speech encoding/decoding necessary, which degrades the speech quality. Accordingly, codec negotiation technologies are necessary for unifying encoding/ decoding in the whole process. Transcoder Free Operation (TrFO), Tandem Free Operation (TFO), and network quality deciding technology are the leading codec negotiation technologies. The TrFO is a mechanism for optimum selection during the establishment of a call. It tries to establish connection between User Equipment (UE) without Transcoder (TC). Its successful fulfillment enables the efficient utilization of bandwidth. The TFO, a standby technology of TrFO, is the negotiation technology of an in-band codec. With it, the user codec stream is free from the compression and decompression by the voice codec, and the quality of voice can accordingly be improved. The network-quantity deciding technology adopts G.711 or G.729 flexibly according to the number of accessed calls. This allows the access of new calls while won’t increase the load of network too much. 展开更多
关键词 TRFO Free TFO Codec Negotiation technologies for 3G MGW
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A Study of the Driving Force Model Revealing Changes in Land Utilization Level Based on 3S Technologies ——The Example of Yuanmou, Yunnan, China
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作者 HEJin-feng CHENGuo-jie YANGZhong 《Wuhan University Journal of Natural Sciences》 CAS 2005年第4期791-795,共5页
This paper introduced the theory and approaches of building driving forcemodels revealing the changes in land utilization level by integrating RS, GPS, and GIS technologiesbased on the example of Yuanmou County of Yun... This paper introduced the theory and approaches of building driving forcemodels revealing the changes in land utilization level by integrating RS, GPS, and GIS technologiesbased on the example of Yuanmou County of Yunnan Province. We first created the land utilizationtype database, natural driving forces for land utilization database, and human driving forces forland utilization database. Then we obtained the dependent and the independent variables of changesin land utilization level by exploring various data. Lastly we screened major factors affectingchanges in land utilization level by using the powerful spatial correlation analysis and maincomponent analysis module of GIS and obtained a multivariable linear regression model of thechangesin land utilization level by using GIS spatial regression analysis module. 展开更多
关键词 land utilization level driving forces data exploration 3s
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Key Technologies of 3G WCDMA Network Sharing
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作者 Zhang Jian (Mobile Division of ZTE Corporation, Shanghai 201203, China) 《ZTE Communications》 2005年第2期5-8,共4页
Based on the latest research findings of 3GPP on network sharing, this paper introduces 4 solutions to WCDMA 3G network sharing: site sharing, common network sharing, geographically split network sharing, and radio ac... Based on the latest research findings of 3GPP on network sharing, this paper introduces 4 solutions to WCDMA 3G network sharing: site sharing, common network sharing, geographically split network sharing, and radio access network sharing. It also analyzes the key network sharing technologies, including the lu-Flex function in Release 5, the UTRAN sharing mechanism in the connected mode in Release 5 and the mechanism of network sharing support enhancement in Release 6. 展开更多
关键词 WCDMA sGsN UTRAN PLMN Key technologies of 3G WCDMA Network sharing
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Applications and Supporting Technologies of 3G Services
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作者 Yan Hua (Mobile Division of ZTE Corporation,Shanghai 201203,China) 《ZTE Communications》 2004年第1期15-17,共3页
The paper introduces two typical 3G services:the mobile multimedia short message service and the streaming media service. The former is considered as a strong driving force to promote the development of 3G services an... The paper introduces two typical 3G services:the mobile multimedia short message service and the streaming media service. The former is considered as a strong driving force to promote the development of 3G services and applications.The latter is regarded as a typical service on future 3G networks.As supporting technologies of 3G services,open service architecture and open mobile architecture are also discussed. 展开更多
关键词 Applications and supporting technologies of 3G services MMs GPP WCDMA
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Thinking About Developing 3G and Broadband Wireless Access Technologies
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作者 Hou Ziqiang (Institute of Acoustics,Chinese Academy of Sciences,Beijing 100080,China) 《ZTE Communications》 2004年第2期50-52,55,共4页
It is wise for fixed operators to make use of broadband wireless access technologies,such as IEEE802.16d,to develop mobile access based on their existing fixed broadband IP networks.Mobile operators have to evolve the... It is wise for fixed operators to make use of broadband wireless access technologies,such as IEEE802.16d,to develop mobile access based on their existing fixed broadband IP networks.Mobile operators have to evolve their networks from 2G to 3G for making full use of their current resources. However,the AII-IP core network will be a general trend since broadband wireless access adopts the connectionless statistical packet multiplexing technology.Based on the introduction of IEEE802.16d,High Speed Downlink Packet Access (HSDPA) and CDMA2000 1x EV-DV technologies,this paper discusses the development trend of broadband wireless access technologies, and concludes that 3G's packet access technologies are the same as IEEE802.16d/e,and AII-IP is the goal.It emphasizes that Chinese TD-SCDMA should develop toward connectionless statistical packet multiplexing as early as possible. 展开更多
关键词 HsDPA rate IEEE GPP Thinking About Developing 3G and Broadband Wireless Access technologies WCDMA Access sCDMA UTRAN UMTs OFDM MBWA
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S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3)的构筑及光催化还原CO_(2)性能 被引量:1
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作者 刘平 朱成才 +1 位作者 李艳阳 要红昌 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期197-208,共12页
通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽... 通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽进行光催化反应。优化后的材料光照5 h后CO_(2)还原产物CO和CH_(4)的产量分别为7.87和4.88μmol·g^(-1)。相对于单相组分,CO和CH_(4)的产量明显提高。光催化活性的提高,归因于ZnFe_(2)O_(4)和WO_(3)异质结的形成以及光生载流子的S型电荷传输模式。 展开更多
关键词 CO_(2)还原 光催化活性 ZnFe_(2)O_(4)/WO_(3) 异质结 s型电荷传输模式
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S3级临床实践指南在口腔医学的发展应用 被引量:1
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作者 陈智 黄心悦 《口腔医学研究》 CAS CSCD 北大核心 2024年第1期1-5,共5页
在口腔医学领域,新的国际S3级指南的出现为相关疾病患者的管理提供了高质量的推荐建议,在国际性指南的基础上,也需结合我国的实际情况进行改编和应用。本文旨在介绍S3级临床实践指南分级系统和基本方法学原理,并对指南改编和本土化应用... 在口腔医学领域,新的国际S3级指南的出现为相关疾病患者的管理提供了高质量的推荐建议,在国际性指南的基础上,也需结合我国的实际情况进行改编和应用。本文旨在介绍S3级临床实践指南分级系统和基本方法学原理,并对指南改编和本土化应用现状进行简要介绍。 展开更多
关键词 临床实践指南 s3级指南 ADOLOPMENT 临床实践
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电液3-UPS/S并联稳定平台参数振动特性分析
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作者 袁晓明 王维锜 +1 位作者 庞浩东 张立杰 《振动与冲击》 EI CSCD 北大核心 2024年第5期52-61,共10页
针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律... 针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律,最后采用四阶龙格库塔法与模态试验对参数振动模型进行验证。结果表明:数值解与理论解之间的最大误差为4.20%,固有频率理论值与试验值之间的最大误差为4.66%,可验证参数振动模型的正确性。 展开更多
关键词 电液3-UPs/s并联稳定平台 压力脉动 参数振动 多尺度法 振动特性
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Application and Implementation of Quest3D Technology in Garden Landscape Design 被引量:1
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作者 刘蓓蓓 赵晓春 +3 位作者 张永帅 唐特 姜明明 王振 《Journal of Landscape Research》 2010年第2期25-28,共4页
The application of virtual reality technology has become more and more influential in garden design. Quest3D as a significant software to realize the virtual reality technology is utilized in this study to make a gard... The application of virtual reality technology has become more and more influential in garden design. Quest3D as a significant software to realize the virtual reality technology is utilized in this study to make a garden roaming demonstration system with the gardening design of a classical courtyard as an example. Besides, the advantages and disadvantages of applying Quest3D technology in garden landscape design are elaborated from the perspective of the selection of Quest3D technology, basic procedures for the selection and establishment of software and hardware. 展开更多
关键词 Virtual reality technology Garden design 3Ds Max QUEsT3D
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木兰花碱调控CD44s/STAT3通路对肺癌细胞迁移、侵袭及干性特征的影响实验研究
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作者 王英 武晓 +1 位作者 刘凤娟 张春玲 《陕西医学杂志》 CAS 2024年第11期1449-1453,1458,共6页
目的:探讨木兰花碱(Mag)对肺癌细胞迁移、侵袭、干性特征的影响及其作用机制。方法:使用不同浓度的Mag(0、10、20、40、80、160μmol/L)作用于肺癌细胞A549,检测细胞存活率,根据半抑制浓度(IC 50)值选择10、20、40μmol/L Mag进行后续... 目的:探讨木兰花碱(Mag)对肺癌细胞迁移、侵袭、干性特征的影响及其作用机制。方法:使用不同浓度的Mag(0、10、20、40、80、160μmol/L)作用于肺癌细胞A549,检测细胞存活率,根据半抑制浓度(IC 50)值选择10、20、40μmol/L Mag进行后续实验。将肺癌细胞A549随机分为A549组、Mag-L组(10μmol/L Mag培养基培养)、Mag-M组(20μmol/L Mag培养基培养)、Mag-H组(40μmol/L Mag培养基培养)和Mag-H+信号转导及转录激活因子3(STAT3)激活剂Colivelin组(40μmol/L Mag+10μmol/L Colivelin培养基培养)。采用平板克隆形成实验检测各组细胞克隆形成数量。采用流式细胞术检测各组细胞凋亡率。采用Transwell实验检测各组细胞迁移及侵袭能力。采用肿瘤细胞成球实验检测细胞干性。采用Western blot检测各组细胞CD44s/STAT3通路及细胞干性相关蛋白表达。结果:与A549组比较,Mag-L组、Mag-M组、Mag-H组细胞克隆形成数量、迁移及侵袭细胞数、干细胞成球数和细胞中CD44s、STAT3、CD133、八聚体结合转录因子4(OCT4)、SRY-box转录因子2(SOX2)表达水平逐渐降低,而细胞凋亡率逐渐升高(均P<0.05)。在高浓度Mag的基础上加入STAT3激活剂Colivelin逆转了以上指标的变化趋势。结论:Mag能够抑制肺癌细胞迁移、侵袭及干性特征,其机制可能与下调CD44s/STAT3通路有关。 展开更多
关键词 肺癌 木兰花碱 CD44s/sTAT3通路 迁移 侵袭 干性特征
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改进YOLOv5s的小样本3D打印点阵结构表面缺陷检测
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作者 安治国 鲜青霖 许亮 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第8期173-180,共8页
3D打印点阵结构已经广泛应用于航空航天、机械和建筑等行业,其表面缺陷分布不均匀且特征微弱,常常造成漏检和误检。针对这一问题,提出了一种YOLOv5s-PD模型。在该模型中,添加了XSPPF模块和空洞金字塔池化模块,提高了模型对不同缺陷特征... 3D打印点阵结构已经广泛应用于航空航天、机械和建筑等行业,其表面缺陷分布不均匀且特征微弱,常常造成漏检和误检。针对这一问题,提出了一种YOLOv5s-PD模型。在该模型中,添加了XSPPF模块和空洞金字塔池化模块,提高了模型对不同缺陷特征的获取能力;针对3D打印点阵结构表面缺陷分布杂乱导致误检率高的问题,在YOLOv5s模型中加入了ECA模块;考虑到3D打印点阵结构表面缺陷尺寸信息无规律并且差异较大而导致的预测框与真实框间方向不一致,采用了SIoU损失函数。采用改进模型对制作的3D打印点阵结构表面缺陷数据集进行检测,结果表明:缺陷检测的召回率达到94.0%,平均精度mAP@0.5达到96.2%,所提出的改进算法可以实现对3D打印点阵结构表面缺陷自动检测。 展开更多
关键词 3D打印 点阵结构 YOLOv5s 缺陷检测 平均精度
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NOTCH3基因C260S位点突变导致CADASIL的临床和影像学特征分析
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作者 孔秀云 代飞飞 +1 位作者 王佳伟 崔世磊 《北京医学》 CAS 2024年第5期380-384,共5页
目的探讨NOTCH3基因第5外显子C260S位点突变导致的伴有皮层下梗死和白质脑病的常染色体显性遗传性脑动脉病(cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy,CADASIL)家系的临床和影像学... 目的探讨NOTCH3基因第5外显子C260S位点突变导致的伴有皮层下梗死和白质脑病的常染色体显性遗传性脑动脉病(cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy,CADASIL)家系的临床和影像学特征。方法选取2021年12月首都医科大学附属北京同仁医院来自同一家庭的CADASIL患者,对所有患者进行NOTCH3基因测序,回顾性分析患者的临床表现和头颅影像学特征。复习既往文献报道的导致同一位置氨基酸改变的其他突变类型的临床及影像学特征。结果4名家庭成员中,包括先证者(46岁,女)及其两个姐姐(分别为48岁和50岁)和女儿(18岁)。先证者及其父亲、两个姐姐都有偏头痛病史,其中大姐有记忆力减退;先证者患有脑梗死及伴有视觉先兆的偏头痛;先证者女儿体健;先证者父亲因脑梗死去世。4名家庭成员均存在C260S位点的NOTCH3基因突变。既往文献无此位点突变的报道,先证者头颅MRI示右侧脑桥亚急性梗死,颞叶、脑室周围及脑干异常高信号改变,其大姐脑桥可见腔隙性梗死灶。结论NOTCH3基因第5外显子c.778T>A(p.C260S)的罕见突变导致的CADASIL发病时间早,早期会出现认知障碍。合并偏头痛的脑干梗死患者,需警惕CADASIL的可能。 展开更多
关键词 伴有皮层下梗死和白质脑病的常染色体显性遗传性脑动脉病 NOTCH3 C260s 第5外显子
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工业CuBi/MgSiO_(3)催化剂再生技术研究
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作者 薛斌 马彩梅 +1 位作者 刘婷婷 刘志威 《山西化工》 CAS 2024年第3期15-17,43,共4页
以1,4丁二醇生产过程中的催化剂再生技术为研究对象,探讨了对废铜铋催化剂再生后,与新鲜铜铋催化剂在整体成型法工艺下的复配技术。通过表征催化剂的粒径分布、比表面积、形貌特征、元素组成和物相组成,确定了乙炔合成丁炔二醇铜铋催化... 以1,4丁二醇生产过程中的催化剂再生技术为研究对象,探讨了对废铜铋催化剂再生后,与新鲜铜铋催化剂在整体成型法工艺下的复配技术。通过表征催化剂的粒径分布、比表面积、形貌特征、元素组成和物相组成,确定了乙炔合成丁炔二醇铜铋催化剂的最优再生处理工艺流程。通过正交试验和强度测试仪分析了成型铜铋催化剂的机械强度可靠性和耐磨性能,为工业CuBi/MgSiO_(3)催化剂的再生提供了新的思路,也为其他催化剂的再生提供了借鉴。 展开更多
关键词 再生技术 工业CuBi/MgsiO_(3)催化剂 复配技术
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基于创新能力培养的3S技术及应用综合实验设计与实践——以地表沉陷InSAR数据处理为例
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作者 朱权洁 谷雷 +1 位作者 于正兴 尹永明 《中国现代教育装备》 2024年第19期134-137,共4页
为提升实验课程效果、培养学生的创新能力,结合新时期防灾减灾专业人才需求,开展了3S技术及应用综合实验设计与实践研究。首先,明确了3S技术及应用综合实验课的目标,提出了相应的实验内容及实践步骤。其次,以地表沉陷专题为例,设计了以I... 为提升实验课程效果、培养学生的创新能力,结合新时期防灾减灾专业人才需求,开展了3S技术及应用综合实验设计与实践研究。首先,明确了3S技术及应用综合实验课的目标,提出了相应的实验内容及实践步骤。其次,以地表沉陷专题为例,设计了以InSAR数据处理为主线的实验方案,包括具体的实验环节和实验过程。该实验充分融合3S技术及应用课程内容,有效结合课堂理论、学生科创、科研实践等,有助于提高学生的学习热情、增强学生的综合能力和创新意识。 展开更多
关键词 3s技术 地表沉陷 实验教学 防灾减灾 INsAR
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固溶工艺对3Al-310S耐热钢组织和力学性能的影响
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作者 张艳梅 余海存 仇秋玲 《特殊钢》 2024年第6期95-101,共7页
通过向普通310S不锈钢中添加3%Al制得3Al-310S耐热不锈钢,试验钢经过不同固溶工艺处理后,采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)及室温拉伸性能测试,研究固溶工艺对3Al-310S耐热钢显微组织和力学性能的影响规律。结果表明,3... 通过向普通310S不锈钢中添加3%Al制得3Al-310S耐热不锈钢,试验钢经过不同固溶工艺处理后,采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)及室温拉伸性能测试,研究固溶工艺对3Al-310S耐热钢显微组织和力学性能的影响规律。结果表明,3Al-310S耐热钢基体组织为奥氏体,随着固溶时间的增加和固溶温度的提高,3Al-310S耐热钢的晶粒尺寸逐渐增大;同时相对应的3Al-310S板材的硬度和抗拉强度逐渐降低,伸长率逐渐提高,当固溶温度为1000℃,固溶时间为10 min时,试验钢的抗拉强度达618.75 MPa,伸长率为33.80%。 展开更多
关键词 3Al-310s耐热钢 固溶工艺 显微组织 力学性能
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基于3S技术下人口普查信息化建设探讨
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作者 王刚 邹梦秋 +1 位作者 王孝龙 胡瑞鹏 《城市勘测》 2024年第4期1-5,共5页
第七次全国人口普查工作首次引入空间地理位置,采用信息化采集手段推进此次人口普查工作的开展。天津市第七次人口普查工作是在结合天津市行政区划、建筑物分布特点,人口流动情况等,充分利用3S、物联网、数据库集群、模糊识别等技术,解... 第七次全国人口普查工作首次引入空间地理位置,采用信息化采集手段推进此次人口普查工作的开展。天津市第七次人口普查工作是在结合天津市行政区划、建筑物分布特点,人口流动情况等,充分利用3S、物联网、数据库集群、模糊识别等技术,解决了基于空间地理位置环境下建筑物快速提取、人口信息电子化采集的问题,形成了一套高效人口普查信息获取工作机制,有力地保证了天津市第七次人口普查和户籍整顿工作的顺利实施。 展开更多
关键词 3s技术 数据库 地理位置 物联网 模糊识别
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Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结的构筑及其光解水产氢性能研究 被引量:7
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作者 于佳慧 姚欣彤 +4 位作者 苏萍 王仕凯 张大凤 葛博 蒲锡鹏 《聊城大学学报(自然科学版)》 2024年第1期52-61,共10页
采用超声辅助研磨煅烧法制备了Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结光催化剂,通过X射线粉末衍射仪、扫描电子显微镜、X射线光电子能谱、固体紫外漫反射等测试技术表征了样品的物相、形貌、化学元素组成以及光吸收能力等物理... 采用超声辅助研磨煅烧法制备了Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结光催化剂,通过X射线粉末衍射仪、扫描电子显微镜、X射线光电子能谱、固体紫外漫反射等测试技术表征了样品的物相、形貌、化学元素组成以及光吸收能力等物理化学性质。在可见光加近红外光照射下进行了光催化析氢性能测试,结果表明,Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S复合材料的光解水产氢性能均优于纯相的Mn_(0.3)Cd_(0.7)S和Cu_(3)Mo_(2)O_(9),其中Cu 3Mo 2O 9的质量分数为1%的Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S显示出最佳的产氢速率(1.554 mmol·h^(-1)·g^(-1)),是Mn 0.3 Cd_(0.7)S的5.5倍。且经过四次循环实验后仍保持较好的光催化活性。此外,根据电化学测试以及红外热成像结果提出了合理的机理,Cu 3Mo 2O 9的光热效应与S型异质结的协同作用是Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S光催化活性提高的关键。 展开更多
关键词 光解水产氢 s型异质结 Mn_(0.3)Cd_(0.7)s Cu_(3)Mo_(2)O_(9) 光热效应
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Simulation on deposition and solidification processes of 7075 Al alloy droplets in 3D printing technology 被引量:7
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作者 李海鹏 李贺军 +2 位作者 齐乐华 罗俊 左寒松 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1836-1843,共8页
In order to study the successive deposition and solidification processes of uniform alloy droplets during the drop-on-demand three dimensional(3D) printing method,based on the volume of fluid(VOF) method,a 3D nume... In order to study the successive deposition and solidification processes of uniform alloy droplets during the drop-on-demand three dimensional(3D) printing method,based on the volume of fluid(VOF) method,a 3D numerical model was employed.In this model,the 7075 alloy with larger temperature range for phase change was used.The simulation results show that the successive deposition and solidification processes of uniform 7075 alloy droplets can be well characterized by this model.Simulated droplets shapes agree well with SEM images under the same condition.The effects of deposition and solidification of droplets result in vertical and L-shaped ridges on the surface of droplets,and tips of dendrites appear near the overlap of droplets due to rapid solidification. 展开更多
关键词 7075 Al alloy uniform droplets 3D model 3D printing technology surface morphology
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