检索结果-内蒙古大学图书馆

作者： zhao, xuwen The Hong Kong Polytechnic University

学位级别：博士

The control of magnetism by electrical means is of importance for both fundamental science and technological applications. Among these methods, electric-field regulation has motivated numerous explorations due to reduced power consumption in devices. Exchange bias (EB) effect has been widely used in commercial electronic devices like spin valve read heads and magnetic random access memories (MRAM). However, the underlying physical mechanism for EB is still not completely understood. Attempts of electric field tuning the EB have been made in the last few decades to explore the physical origins of EB and to functionalize EB- based devices. In this thesis, I studied electric-field based regulation of EB in antiferromagnetic La 0.35 Sr 0.65 MnO 3 (AF-LSMO)/ferromagnetic La 0.7 Sr 0.3 MnO 3 (FM-LSMO) bilayer structures and single-layer LaMnO 3 (LMO) films. Before investigating the electric-field based modulation of EB in AF-LSMO/FM-LSMO, the impact of AF layer growth temperature on the EB behaviour in AF-LSMO/FM-LSMO bilayers and low-voltage pulsing effect on FM-LSMO and AF-LSMO single layers were studied. It was demonstrated that the best modulation was obtained in AF-LSMO (15 nm)/FM-LSMO (5 nm) structure. The EB effect was suppressed by positive pulses but only slightly enhanced by negative pulses, suggesting a weak tunability of negative pulses. By analysing high angle annular dark field (HAADF) images and electron energy loss spectroscopy (EELS) for different gating states, oxygen vacancies in AF-LSMO layer created by +10 V pulses were proved to exist from the top surface to the interface area while -10 V pulses can only slightly deplete these oxygen vacancies at the top surface of AF- LSMO layer, which elaborated the strong and weak modulation of EB effect in AF-LSMO/FM- LSMO by positive and negative pulses, respectively. The final study focused on the regulation of EB in single-layer LMO epitaxial thin films via ionic liquid (IL) gating. It was demonstrated that +2

关键词：

来源：评论

学校读者我要写书评

暂无评论

Bill of material consistency reconstruction method for complex products driven by digital twin

引用

INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2022年第1-2期120卷 185-202页

作者： Wang, Yunrui Ren, Wenzhe Zhang, Chuanwei zhao, xuwen Xian Univ Sci & Technol Sch Mech Engn Xian 710054 Shaanxi Peoples R China

Bill of material (BOM), as the core data in the complete life cycle management of complex products, is the primary data that supports the deep integration of intelligent and information technology of complex products. They are aiming at the characteristics of high complexity, solid dynamics, and many uncertain factors in the BOM reconstruction process of complex products. The digital twin technology is introduced into the BOM reconstruction process, and the BOM consistency reconstruction mechanism of complex products is constructed. The sequence process of BOM data flow is analyzed. The focus is on the reconstruction process of engineering BOM (EBOM), process BOM (PBOM), manufacturing BOM (MBOM), and maintenance BOM (WBOM) based on digital twin. The rationality of the constructed BOM is verified by establishing a virtual model, which promotes continuous optimization and improvement of the BOM. This paper also discusses the key technologies of data dynamic perception, digital threading, simulation modeling decoupling, and coupling in the process of BOM reconstruction. Finally, the feasibility of the proposed method is verified by combining the BOM reconstruction process of an enterprise bogie and the construction of the bogie twin system, which provides a reference for improving the accuracy, integrity, and consistency of the BOM reconstruction process of complex products.

关键词： Complex products Digital twin Consistency BOM reconstruction

来源：评论

学校读者我要写书评

暂无评论

The s-d interaction induced hydrogen trapping effect in α-U (130)/ twin boundary region

引用

SURFACES AND INTERFACES 2025年 61卷

作者： Jin, Jingyuan Zhang, Yujuan Lv, Wenting zhao, xuwen Miao, Chengzhen Ji, Hefei Yang, Yu Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Inst Appl Phys & Computat Math LCP Beijing 100088 Peoples R China China Acad Engn Phys Inst Mat Res Mianyang 621900 Peoples R China

Hydrogen embrittlement is a serious obstacle to the safe storage and practical application of metal uranium. In this work, the hydrogen solution characteristics in the (130)/[001] twin grain boundary region in alpha-U metal are studied by first-principles theoretical and electron backscatter diffraction experimental methods. Our results show that the solution energy of hydrogen atom is the lowest at the (130)/[001] twin boundary plane, and increases as the distance from the twin boundary expands. Hydrogen atoms need to overcome energy barriers to diffuse both along and vertical to the twin boundary plane, i.e., the H atoms are trapped at the interstitial sites in the twin boundary region. It is also found that the s-d interaction between H and U atoms has induced the hydrogen trapping effect. Furthermore, the existence of Nb atom notably lowers the hydrogen solution energy and deepens the hydrogen trap in the region of (130)/[001] twin boundary, which is attributed to the intensified s-d interaction between H and U/Nb atoms. These findings are expected to reveal the underlying mechanism of the microstructural evolution of H atoms in U and provide a theoretical guidance for enlightenment to mitigate or inhibit hydriding corrosion in U metal.

关键词： Hydrogen corrosion Uranium Grain boundary First-principles Electron backscatter diffraction

来源：评论

学校读者我要写书评

暂无评论

Multisite synergistic interaction induced selective adsorption of CB5-Ti3C2T2 complex for strontium ion: A combined theoretical and experimental study

引用

JOURNAL OF HAZARDOUS MATERIALS 2025年 487卷 137288页

作者： Li, Sifan Zhang, Pengcheng Zhang, Yujuan Qiu, Kaikai Wang, Lin Lan, Jianhui Zhang, Yu zhao, xuwen Miao, Chengzhen Shi, Weiqun Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Chinese Acad Sci Inst High Energy Phys Lab Nucl Energy Chem Beijing 100049 Peoples R China Shanghai Jiao Tong Univ Sch Nucl Sci & Engn Minist Educ Shanghai 200240 Peoples R China Shanghai Jiao Tong Univ Key Lab Nucl Power Syst & Equipment Minist Educ Shanghai 200240 Peoples R China

In this work, we use a well-defined water-soluble macrocyclic molecule cucurbit[5]uril (CB5) to modify 2D Ti3C2T2 MXene and assemble a novel high-performance adsorbent CB5-Ti3C2T2 for Sr ion by density functional theory and experimental methods. The structural stabilities of two distinct types of CB5-Ti3C2T2 (T = F, O and OH) complexes, i.e., CB5-Ti3C2T2(V) and CB5-Ti3C2T2(P) configurations are proved by binding energy and ab initio molecular dynamics (AIMD) simulations. Calculations of adsorption properties reveal that all the considered CB5-Ti3C2T2 complexes can act as efficient adsorbents for Sr ion, among which CB5-Ti3C2O2 complex possesses the best performance. The high affinity (the calculated adsorption energies < -7.6 eV) and selectivity of CB5-Ti3C2T2 complex for Sr ion are attributed to the synergistic effect between CB5 molecule and Ti3C2T2 MXene in the adsorption process, which arises from the multisite interactions of portal carbonyl groups of CB5 and surface functional groups of Ti3C2T2 towards Sr. Finally, CB5-Ti3C2T2 complex was successfully synthesized, and experimental results confirm its synergistic effect, good selectivity and high removal efficiency for Sr ions. In the treatment of strontium-containing wastewater with low concentrations, the distribution coefficient and decontamination factor of CB5-Ti3C2T2 for Sr were determined to be as high as 2.88 x 10(5) mL/g and 144.9, respectively, and the separation factor (SFSr/Ca) achieved a notable value of 67. 5. This work is expected to present a new strategy for the construction of high-performance MXene-based adsorbent for radionuclide elimination.

关键词： MXene Cucurbit[5]uril Adsorption Strontium First-principles simulation

来源：评论

学校读者我要写书评

暂无评论

An ultrastable sodium-ion battery anode enabled by carbon-coated porous NaTi2(PO4)3 olive-like nanospheres

引用

JOURNAL OF COLLOID AND INTERFACE SCIENCE 2023年第1期635卷 417-426页

作者： Man, Yuehua Sun, Jianlu zhao, xuwen Duan, Liping Fei, Yating Bao, Jianchun Mo, Xiangyin Zhou, Xiaosi Nanjing Normal Univ Sch Chem & Mat Sci Nanjing 210023 Peoples R China City Univ Hong Kong Dept Mat Sci & Engn Kowloon Hong Kong 999077 Peoples R China

NaTi2(PO4)3 (NTP) is a promising anode material for sodium-ion batteries (SIBs). It has drawn wide atten-tion because of its stable three-dimensional NASICON-type structure, proper redox potential, and large accommodation space for Na'. However, the inherent low electronic conductivity of the phosphate framework reduces its charge transfer kinetics, thus limiting its exploitation. Therefore, this paper pro-poses a material with carbon-coated porous NTP olive-like nanospheres (p-NTP@C) to tackle the issues above. Based on experimental data and theoretical calculations, the porous structure of the material is found to be able to provide more active sites and shorten the Na' diffusion distance. In addition, the car-bon coating can effectively improve the electron and Na' diffusion kinetics. As the anode material for SIBs, the p-NTP@C olive-like nanospheres exhibit a high reversible capacity (127.3 mAh g-1 at 0.1 C) and ultrastable cycling performance (84.8% capacity retention after 10,000 cycles at 5 C). Furthermore, the sodium-ion full cells, composed of p-NTP@C anode and Na3V2(PO4)2F3@carbon cathode, also deliver excellent performance (75.7% capacity retention after 1000 cycles at 1 C). In brief, this nanostructure design provides a viable approach for the future development of long-life and highly stable NASICON-type anode materials.(c) 2022 Elsevier Inc. All rights reserved.

关键词： NaTi2(PO4)3 Porous structure Carbon coating Anode Sodium-ion battery

来源：评论

学校读者我要写书评

暂无评论

A cohort of five cases with asymmetric conjoined twining and literature review

引用

PEDIATRIC SURGERY INTERNATIONAL 2022年第1期38卷 169-181页

作者： Zhi, Xiufang Hu, Bo zhao, xuwen Chen, Jing Gu, Chunyu Pu, Linjie Fang, Yulian Cai, Chunquan Tianjin Med Univ Grad Coll Tianjin 300070 Peoples R China Tianjin Univ Childrens Hosp Tianjin Childrens Hosp Tianjin 300134 Peoples R China Tianjin Childrens Hosp Dept Neonatal Surg Tianjin 300134 Peoples R China Tianjin Childrens Hosp Dept Radiol Tianjin 300134 Peoples R China Tianjin Pediat Res Inst Tianjin 300134 Peoples R China Tianjin Key Lab Birth Defects Prevent & Treatment Tianjin 300134 Peoples R China Tianjin Childrens Hosp Dept Neurosurg 238 Longyan Rd Tianjin 300134 Peoples R China

Purpose Asymmetric conjoined twining (ACT) is a form of conjoined twining which is a rare malformation of monochorionic monoamniotic twin pregnancy. Most publications were single case reports. We reported a cohort of five cases with ACT from a single tertiary medical center and reviewed the case reports of ACT over the last decade to enrich the clinical research of this disease and summarized the clinical features of the disease. Methods We reviewed five cases of ACT admitted in Tianjin Children's Hospital from 17 March, 2008, through 7 March 2017. The cohort was analysed from general information, imaging manifestations, separation surgery, histopathological findings, outcome and follow-up. We searched the English literatures on case reports of ACT over the past decade from the PubMed database and presented details about the clinical characteristics, treatment, and prognosis of all cases. Results There were four males and one female in our cohort. Among the five cases, two parasites were located in epigastrium, two in rachis, and one in retroperitoneum (fetus in fetu, FIF). All of the parasites were separated successfully by operation in five cases and were confirmed to be ACT by histopathology reports. Four patients made an uneventful recovery except for one case of wound infection. All of them were doing well in follow-up. In the literature review, we found 41 cases of exoparasitic heteropagus twining (EHT) and 63 cases of FIF. Conclusions ACT is very rare and usually diagnosed by prenatal ultrasonography (US). Computed tomography (CT) and magnetic resonance imaging (MRI) examinations are essential imaging examinations before separation surgery to delineate the anatomical relationship between the autosite and the parasite. In general, the separation surgery of ACT is less complicated and the prognosis is better compared with the symmetric conjoined twining (SCT).

关键词： Asymmetric conjoined twining Separation surgery Autosite Parasite

来源：评论

学校读者我要写书评

暂无评论

High-performance photodetectors based on two-dimensional perovskite crystals with alternating interlayer cations

引用

Journal of Materiomics 2023年第4期9卷 817-823页

作者： Yezhan Li Zhengxun Lai You Meng Wei Wang Yuxuan Zhang xuwen zhao Di Yin Weijun Wang Pengshan Xie Quan Quan SenPo Yip Johnny C.Ho Department of Materials Science and Engineering City University of Hong Kong999077Hong Kong SARChina Institute for Materials Chemistry and Engineering Kyushu UniversityFukuoka816-8580Japan State Key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong999077Hong Kong SARChina

Organic-inorganic halide perovskite,as a low-cost,solution-processable material with remarkable optoelectronic properties,is ideal candidate to fabricate high-performance photodetectors and is expected to significantly reduce device *** to the common Dion-Jacobson and Ruddlesden-Popper two-dimensional(2D)layered hybrid perovskite compounds,the perovskites with alternating cations in the interlayer(ACI)phase show higher crystal symmetry and narrower optical bandgaps,which exhibit great potential for excellent photodetection ***,we report a high-performance photodetector based on the 2D bilayered hybrid lead halide perovskite single crystal with the ACI phase(GAMA_(2)Pb_(2)I_(7);GA=C(NH_(2))_(3)and MA=CH_(3)NH_(3)).The single-crystal photodetector exhibits high photoresponsivity of 1.56,2.54,and 2.60 A/W for incident light wavelengths of 405,532,and 635 nm under 9.82 nW,respectively,together with the correspondingly high detectivity values of 1.86×10^(12),3.04×10^(12),and 3.11×10^(12)Jones under the same operating ***,a high-resolution imaging sensor is built based on the GAMA_(2)Pb_(2)I_(7)single-crystal photodetector,confirming the high stability and photosensitivity of the imaging *** results show that the 2D hybrid lead halide perovskites with alternating interlayer cations are promising for high-performance visible light photodetectors and imaging systems.

关键词： Photodetector Two-dimensional Hybrid perovskite Alternating interlayer cation Imaging

来源：评论

学校读者我要写书评

暂无评论

Erosion wear resistance mechanism of erosion ripples

引用

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE 2022年第19期236卷 10359-10369页

作者： Zhang, Yan zhao, xuwen Wang, Qi Wang, Tianqi Tang, Yuling Tianjin Univ Sci & Technol Tianjin Key Lab Integrated Design & On Line Monit Tianjin Peoples R China Tianjin Univ Sci & Technol Coll Mech Engn Tianjin Peoples R China

Erosion ripples widely exist on natural and industrial surfaces suffering gas-solid flow erosion. During the steady state of erosion ripples formation, the material removal and plastic flow rate of the material basically reach a dynamic equilibrium. In this state, the erosion rate of the surface material is steady and at a low level. In this paper, the relationship between erosion ripples and the erosion characteristics of surface materials was explored by experimental and simulation methods. Under the conditions of air pressures of 0.3, 0.4 and 0.5 MPa and erosion angles of 30 degrees, 40 degrees and 50 degrees, several erosion ripples were prepared on the surface of 1060 aluminium alloy samples by sandblasting. According to the obtained morphological parameters and orthogonal test design, rippled samples with rectangular, triangular and semicircular groove sections were designed. The effect of morphology parameters on the erosion resistance of the sample was analysed by a sandblasting test. The results showed that the rippled samples have lower erosion rates than the plate sample. The cross-sectional shape of grooves is the most obviously affected factor. The velocity distribution and surface pressure distribution on the surface of rippled and plate samples were analysed by FLUENT software, and the results showed that the low-speed reflow vortex will be formed in grooves of erosion ripples that can change the near-wall flow field conditions. The differential pressure generated on two sides of the ridge between adjacent grooves, as well as the area decrease of erosion caused by the "shaded effect," may be the cause of the erosion resistance. The results of this study can provide new insight into the active erosive wear resistance method of mechanical components.

关键词： erosive wear erosion ripple gas-solid flow sandblasting near-wall flow field

来源：评论

学校读者我要写书评

暂无评论

番茄红素通过SIRT1/NF-κB轴抑制肾癌786-O细胞增殖且促进其凋亡

引用

中国肿瘤生物治疗杂志 2023年第9期30卷 789-796页

作者：刘伟杨树芹赵序雯滕州市中心人民医院病理科山东滕州277500

目的:探讨番茄红素通过沉默信息调节因子1(SIRT1)/核因子-κB(NF-κB)轴对肾癌786-O细胞增殖、凋亡的影响。方法:常规培养人正常肾细胞HK-2和人肾癌细胞786-O,实验分为对照组(0.1%DMSO)、顺铂组(40μg/mL)、番茄红素低质量浓度(2.5μg/... 详细信息

目的:探讨番茄红素通过沉默信息调节因子1(SIRT1)/核因子-κB(NF-κB)轴对肾癌786-O细胞增殖、凋亡的影响。方法:常规培养人正常肾细胞HK-2和人肾癌细胞786-O,实验分为对照组(0.1%DMSO)、顺铂组(40μg/mL)、番茄红素低质量浓度(2.5μg/mL)组、番茄红素高质量浓度(5μg/mL)组、番茄红素(5μg/mL)+EX527(SIRT1抑制剂)(3μmol/L)组。CCK-8法、克隆形成实验检测各组HK-2、786-O细胞的增殖能力,流式细胞术检测各组786-O细胞的凋亡,RH123、DCFH-DA染色分别检测各组786-O细胞的线粒体膜电位(MMP)、活性氧(ROS)水平,WB法检测各组786-O细胞中凋亡相关蛋白BAX、Bcl-2、C-casp3和SIRT1/NF-κB轴相关蛋白SIRT1、p-NF-κB蛋白的表达。786-O细胞移植瘤实验检测番茄红素低(5 mg/kg)、高质量浓度(20 mg/Kg)、顺铂(2 mg/kg)、番茄红素(20 mg/kg)+EX527(10 mg/kg)对移植瘤生长的影响,TUNEL法检测各组移植瘤组织中的细胞凋亡。结果:番茄红素呈剂量依赖性地抑制786-O细胞的增殖活性,番茄红素、顺铂均明显抑制786-O细胞的克隆形成能力且促进其凋亡,细胞中MMP损伤率升高而ROS水平降低,凋亡相关蛋白BAX、C-casp3表达均显著升高(均P<0.05)而Bcl-2表达下调(P<0.05),SIRT1表达显著升高(P<0.05)而p-NF-κB的表达显著降低(P<0.05),上述作用均可被EX527逆转;番茄红素、顺铂抑制786-O细胞移植瘤的生长且促进其细胞凋亡,其作用也能被EX527逆转。结论:番茄红素通过上调SIRT1、抑制NF-κB通路的激活进而抑制786-O细胞增殖且诱导其凋亡。

关键词：肾癌 786-O细胞番茄红素沉默信息调节因子1 核因子-κB 增殖凋亡

来源：评论

学校读者我要写书评

暂无评论

高频超声对新生儿坏死性小肠结肠炎需手术治疗的预测价值

引用

中华新生儿科杂志（中英文） 2024年第1期39卷 18-22页

作者：杨薇裴广华徐魏军赵绪稳天津市儿童医院(天津大学儿童医院)超声科天津300074 天津市儿童医院(天津大学儿童医院)新生儿外科天津300074

目的探讨高频超声对新生儿坏死性小肠结肠炎(necrotizing enterocolitis,NEC)需手术治疗的预测价值。方法选择2018年1月至2021年12月天津市儿童医院新生儿外科诊断为Bell分期Ⅱ期以上的NEC患儿进行回顾性分析。根据是否手术分为手术组... 详细信息

目的探讨高频超声对新生儿坏死性小肠结肠炎(necrotizing enterocolitis,NEC)需手术治疗的预测价值。方法选择2018年1月至2021年12月天津市儿童医院新生儿外科诊断为Bell分期Ⅱ期以上的NEC患儿进行回顾性分析。根据是否手术分为手术组和非手术组,比较两组超声检查肠蠕动、肠壁血流灌注、肠壁积气、门静脉积气、腹腔积液内透声、腹腔积液深度、肠壁厚度情况,采用logistic回归分析NEC患儿需手术干预的危险因素,并做受试者工作特征曲线分析,计算联合因子和单一因子预测NEC患儿急性期需手术治疗的价值。结果共纳入40例,手术组18例,非手术组22例。两组超声检查肠壁积气、腹腔积液深度差异无统计学意义(P>0.05);手术组肠蠕动减弱、门静脉积气、肠壁血流灌注减少、腹腔积液透声差比例均高于非手术组,肠壁厚度小于非手术组(P<0.05)。Logistic回归分析显示,腹腔积液透声差、肠壁变薄、肠壁血流灌注减少及肠蠕动减弱对NEC患儿需手术治疗有较高的预测效能。受试者工作特征曲线分析显示预测NEC患儿需手术治疗的肠壁厚度临界值为1.2 mm,曲线下面积0.746,敏感度87.5%,特异度65.6%;联合因子预测NEC患儿需手术干预的曲线下面积为0.867,敏感度96.9%,特异度75.8%。结论高频超声显示肠蠕动减弱、肠壁血流灌注减少、肠壁变薄及腹腔积液内透声差对NEC急性期是否需手术治疗有较高的预测效能。

关键词：新生儿坏死性小肠结肠炎超声肠壁积气门静脉积气

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：