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WITHDRAWN: The Correlation between 25-Hydroxyvitamin D Levels and Testosterone Levels in Type 2 Diabetic Male Patients 2 型糖尿病男性患者体内 25-羟维生素 D 水平与睾酮水平之间的相关性。

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2025-01-01 DOI: 10.2174/1871530322666220524104929

Mohamed M Aboelnaga, Nahed Abdullah

Since the authors are not responding to the editor’s requests to fulfill the editorial requirement, therefore, the article has been withdrawn.

Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused.

The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php.

It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

背景：维生素D不足和睾酮水平低是T2DM男性患者的常见病，维生素D被认为可调节垂体-睾丸功能：我们研究了 2 型糖尿病男性患者的睾酮水平与循环维生素 D 之间的关系：在这项横断面研究中，我们招募了 95 名 2 型糖尿病男性患者，并调查了循环中维生素 D 的形式，即 25- 羟基维生素 D（25(OH) D）。25（OH）D水平结果在 2 型糖尿病男性患者中，睾酮缺乏症的发病率为 46.3%。睾酮缺乏的糖尿病患者的 25(OH) D 水平明显低于睾酮正常的患者。我们观察到，与睾酮充足的患者相比，睾酮缺乏的糖尿病患者维生素 D 缺乏的发病率更高。此外，在缺乏维生素 D 的男性糖尿病患者中，与不缺乏维生素 D 的患者相比，总睾酮水平明显较低，但 LH 水平却不低。我们通过线性回归分析发现，25（OH）D 能显著预测男性糖尿病患者的总睾酮水平。然而，在排除大白蛋白尿患者后，这种关联不再具有统计学意义。此外，在逻辑回归分析中，维生素 D 缺乏也是导致睾酮缺乏的一个重要风险因素：结论：与睾酮正常的男性糖尿病患者相比，睾酮缺乏的男性糖尿病患者的25（OH）D水平明显较低，维生素D缺乏的患病率也较高。同样，维生素 D 缺乏患者的睾酮水平也较低。总体而言，25（OH）D 能显著预测总睾酮水平。因此，维生素 D 缺乏是男性糖尿病患者睾酮缺乏的一个重要风险因素。

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引用次数: 0

Development of a high-intensity compact D-D neutron generator based on RF ion sources 基于射频离子源的高强度紧凑D-D中子发生器的研制

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-30 DOI: 10.1016/j.vacuum.2024.113909

Zhenqing Zhu , Yuzhong Qian , Mengmeng Li , Xin Tao , Bing Hong , Jichao Wang , Jiasheng Chen , Wei Xu , Xiancai Meng , Lizhen Liang , Chundong Hu

The present paper presents a compact D-D neutron generator designed for imaging applications, capable of producing a neutron yield exceeding 10⁹n/s. Here, a RF ion source ignited by an external antenna is envisaged, and the discharge chamber's design involves a double-layer glass cylinder for active cooling of the discharge chamber. At the same time, by improving the chamber's size and strategically positioning the magnetic field outside -multi-cusp and top magnetic field, the efficiency of the ion source is enhanced, including increased the extract beam current and extended ion source life, thus fostering increased neutron production and prolonged service duration. The experimental results show that under the condition of RF power 400 W and high voltage negative 95 kV, the beam current is extracted by 9.5 mA, and the stable operation of 24 h is realized, which the neutron yield reaches 1.1 × 10⁹ n/s with effective operation time surpassing 95 %.

本文介绍了一种用于成像应用的紧凑的D-D中子发生器，能够产生超过109n/s的中子产率。在这里，设想了一个由外部天线点燃的射频离子源，放电室的设计包括一个双层玻璃圆柱体，用于放电室的主动冷却。同时，通过改进腔室的尺寸，将磁场战略性地定位在多尖端和顶部磁场之外，提高了离子源的效率，包括提高了提取束电流，延长了离子源寿命，从而提高了中子产量，延长了使用寿命。实验结果表明，在射频功率为400 W、高压为负95 kV的条件下，提取束流9.5 mA，实现了24 h的稳定运行，中子产率达到1.1 × 109 n/s，有效运行时间超过95%。

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引用次数: 0

Compositional design of slag for homogenized rare earth treatment by slag-steel interaction under vacuum 真空下渣钢相互作用均质稀土处理渣的成分设计

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-29 DOI: 10.1016/j.vacuum.2024.113905

Yu Liu , Liqin Zhu , Pengzhao Zhang , Ke Hu , Guangqiang Li , Xijie Wang

Reduction of La₂O₃ in molten slag by the C in liquid steel during slag-steel interaction under vacuum is expected to achieve homogenized La treatment for steel. To develop the appropriate slag for La treatment, the liquidus temperature, viscosity and fluoride vaporization of 50 wt%CaF₂-30 wt%CaO-(20-x)wt%Al₂O₃-xwt%La₂O₃ slag were studied, as well as the La distribution between the La₂O₃ containing slag and GCr15 steel under vacuum. The results show that the liquidus temperature of slag firstly decreases with the increase of La₂O₃ content from 0 to 5 wt%, and then increases as the La₂O₃ content continuously increases. The LaAlO₃ phase starts to precipitates in slag when La₂O₃ content of slag exceeds 10 wt%, which accounts for the increases on liquidus temperature. Thus, the La₂O₃ content in slag should not exceed 15 wt%. La₂O₃ can play the depolymerization role on slag melts, which contributes to the decrease in slag viscosity. Furthermore, the increase of La₂O₃ content in slag decreases vapor pressure of CaF₂ and AlF₃, and fluoride vaporization is inhibited. Rare earth treatment with considerable La content through slag-steel interaction that dissolved C in liquid GCr15 steel reacts with La₂O₃ in molten slag is realized under vacuum. The La content in GGr15 equilibrated with slag bearing 15 wt% La₂O₃ under 0.5–1 kPa is 0.0135 wt%.

在真空条件下，钢渣-钢相互作用过程中，钢水中的C对熔渣中的La2O3进行还原，有望实现钢的均匀化La处理。为了研制出合适的La处理渣，研究了50wt % caf2 - 30wt %CaO-(20-x)wt%Al2O3-xwt%La2O3渣的液相温度、粘度和氟化汽化，以及真空条件下含La2O3渣与GCr15钢之间的La分布。结果表明：当La2O3含量从0 wt%增加到5 wt%时，炉渣的液相温度先降低，然后随着La2O3含量的不断增加而升高；当渣中La2O3含量超过10 wt%时，渣中开始析出LaAlO3相，这是液相温度升高的原因。因此，渣中La2O3的含量不应超过15 wt%。La2O3对熔渣具有解聚作用，有利于降低熔渣粘度。此外，渣中La2O3含量的增加降低了CaF2和AlF3的蒸气压，抑制了氟的汽化。在真空条件下，通过钢渣相互作用，实现了GCr15钢液中溶解的C与熔渣中La2O3的反应，实现了La含量较高的稀土处理。在0.5-1 kPa条件下，含15wt % La2O3渣的GGr15中La含量为0.0135 wt%。

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引用次数: 0

Degradation effects of the rafts and dislocation network on creep property of single crystal superalloy at medium temperature 筏形和位错网络的退化对单晶高温合金中温蠕变性能的影响

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-29 DOI: 10.1016/j.vacuum.2024.113904

Yuan Cheng , Fugen Xu , Xinbao Zhao , Quanzhao Yue , Bin Yu , Wanshun Xia , Yuefeng Gu , Ze Zhang

Generally, raft structure and interfacial dislocation networks enhance the creep resistance at elevated temperatures above 1000 °C and low stresses in Ni-based single crystal superalloys. However, the formation of raft structure and dislocation networks by raising the Mo content increased the creep rate at 900 °C and 392 MPa, accelerating the final failure. The formation of rafts was closely related to the creep rate acceleration, promoting dislocations piling up at the γ′/γ interface and the shearing events in the γ′ phase. Moreover, the dislocation networks formed at 900 °C and 392 MPa did not differentiate significantly with different Mo content, which could not enhance the creep resistance as expected. This work revealed the microstructural evolution at medium temperature and provided a new perspective for understanding the creep mechanisms and alloy design.

一般来说，筏形结构和界面位错网络增强了ni基单晶高温合金在1000℃以上高温和低应力下的抗蠕变能力。而在900℃和392 MPa下，提高Mo含量形成的筏状结构和位错网络增加了蠕变速率，加速了最终的破坏。筏体的形成与蠕变速率加速、γ′/γ界面位错堆积和γ′相剪切事件密切相关。此外，在900℃和392 MPa下形成的位错网络不随Mo含量的不同而有明显的差异，不能如预期的那样增强抗蠕变能力。研究结果揭示了合金在中温条件下的微观组织演变，为进一步认识蠕变机理和合金设计提供了新的视角。

引用次数: 0

Molecular dynamics study on the edge effect of single crystal Ni with two indenters nanoindentation 双压头纳米压痕单晶Ni边缘效应的分子动力学研究

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-28 DOI: 10.1016/j.vacuum.2024.113900

Ruihan Li , Ziteng Li , Shuhao Kang , Chao Long , Huan Liu , Pengyue Zhao , Duo Li

The edge effect and the formation and evolution of dislocations in nanoindentation were studied using molecular dynamics methods. A series of molecular dynamics models of two indenter nanoindentation was constructed, and diamond indenters were used for indentation simulation. This paper analyzes the effects of two indenters distance and indentation depth on the edge side extrusion, surface collapse, indentation force, internal defects, and stress of single crystal Ni workpieces. The results show that the number of particles extruded from the side does not increase linearly with the indentation distance increasing, the magnitude of indentation force changes with the increase of indentation depth and is influenced by the distance between the indenters, and the internal defects of single crystal nickel workpieces change with the change of indentation distance and increase with the increase of indentation depth. This work has a positive impact on understanding the nanoindentation processing of single crystal Ni and can help to understand the mechanism of internal dislocation formation in workpieces under multiple indenters indentation.

采用分子动力学方法研究了纳米压痕中的边缘效应和位错的形成与演化。建立了两种压头纳米压痕的分子动力学模型，并采用金刚石压头进行压痕模拟。分析了两个压头距离和压痕深度对单晶Ni工件边缘侧挤压、表面塌陷、压痕力、内部缺陷和应力的影响。结果表明：从侧面挤出的颗粒数不随压痕距离的增加而线性增加，压痕力的大小随压痕深度的增加而变化，并受压痕间距的影响，单晶镍工件的内部缺陷随压痕距离的变化而变化，随压痕深度的增加而增加。本研究对理解单晶Ni的纳米压痕加工具有积极的影响，有助于理解多个压痕下工件内部位错形成的机理。

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引用次数: 0

Editorial Board and Vacuum units 编辑委员会和真空单位

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-28 DOI: 10.1016/S0042-207X(24)00916-3

引用次数: 0

Synthesis and irradiation behavior of (Gd0.2Sm0.2Dy0.2Er0.2Yb0.2)2Ti2O7 high-entropy pyrochlore waste forms consolidated by spark plasma sintering 放电等离子烧结固结（Gd0.2Sm0.2Dy0.2Er0.2Yb0.2）2Ti2O7高熵焦绿石废弃物的合成及辐照行为

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-28 DOI: 10.1016/j.vacuum.2024.113893

Xiaoyu Ji , Penghui Lei , Jiahao Chen , Jie Qiu , Qing Peng , Di Yun

The development of spent fuel reprocessing, which generates large amounts of high-level waste, necessitates effective management of waste containing radioactive elements. Pyrochlore (A₂B₂O₇) is considered one of the most promising immobilized matrixes for high-level waste due to its excellent physicochemical stability and irradiation resistance. A novel kind of high-entropy pyrochlore ceramic (Gd_0.2Sm_0.2Dy_0.2Er_0.2Yb_0.2)₂Ti₂O₇, as an improved waste form matrix, was successfully synthesized using spark plasma sintering in this work. The mechanical properties, physical density, and microstructure of the densified pellets have been investigated in relation to different sintering temperatures (ranging from 1000 °C to 1400 °C). A single-component pyrochlore phase high-entropy ceramic was densified at 1300 °C, achieving a maximum hardness of 12.68 GPa and a density of 97.64 %. The irradiation tolerance of high-entropy pyrochlore was assessed by ion irradiation of 400 keV He⁺ with 10 × 10¹⁷ ions/cm² at room temperature (RT). Ion irradiation can induce the transformation of the pyrochlore superlattice of (Gd_0.2Sm_0.2Dy_0.2Er_0.2Yb_0.2)₂Ti₂O₇ into a fluorite sublattice. Compared to Gd₂Ti₂O₇, (Gd_0.2Sm_0.2Dy_0.2Er_0.2Yb_0.2)₂Ti₂O₇ exhibits significantly reduced irradiation damage with suppressed generation and coalescence of helium bubbles due to chemical disorder and lattice distortion. High-entropy pyrochlore (Gd_0.2Sm_0.2Dy_0.2Er_0.2Yb_0.2)₂Ti₂O₇ exhibits superior mechanical properties and irradiation resistance, suggesting its application as a promising immobilization matrix for nuclear waste.

发展产生大量高放射性废物的乏燃料后处理，必须对含有放射性元素的废物进行有效管理。焦绿石（A2B2O7）因其优异的物理化学稳定性和耐辐照性被认为是高放废物最有前途的固定化基质之一。本文采用火花等离子烧结技术，成功地合成了一种新型的高熵烧绿陶瓷（Gd0.2Sm0.2Dy0.2Er0.2Yb0.2）2Ti2O7。研究了不同烧结温度（1000°C至1400°C）下致密球团的机械性能、物理密度和微观结构。在1300℃下致密化了一种单组分焦绿石相高熵陶瓷，最大硬度为12.68 GPa，密度为97.64%。采用10 × 1017个离子/cm2的400 keV He+离子辐照，评价了高熵焦绿盐的辐照耐受性。离子辐照可诱导（Gd0.2Sm0.2Dy0.2Er0.2Yb0.2）2Ti2O7的焦绿盐超晶格转变为萤石亚晶格。与Gd2Ti2O7相比，（Gd0.2Sm0.2Dy0.2Er0.2Yb0.2）2Ti2O7由于化学无序和晶格畸变抑制了氦泡的产生和聚并，辐照损伤明显减小。高熵焦绿石（Gd0.2Sm0.2Dy0.2Er0.2Yb0.2）2Ti2O7具有优异的力学性能和耐辐照性能，是一种很有前途的核废料固定化基质。

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引用次数: 0

Forming characteristic analysis in twin tungsten electrode – Wire electrode indirect arc based additive manufacturing 双钨电极-丝电极间接电弧增材制造成形特性分析

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-28 DOI: 10.1016/j.vacuum.2024.113902

Yanli Zhu , Sheng Gao , Shibao Yu , Dianguo Ma

In this study, the forming characteristics of twin tungsten electrode – wire electrode indirect arc (TTWIA) based additive manufacturing were preliminarily investigated. Arc shape, droplet transfer behavior, molten pool temperature field, and molten pool flow state were obtained respectively. Results showed that the increase of arc current enhanced the coupling degree of TTWIA arc, and promoted the detachment of the droplet from the wire, which contributed to streaming spray transfer of the droplet. Besides, the temperature and fluidity of the molten pool both increased with the increase of the arc current due to the increasing temperature of the arc, enthalpy carried by the droplets, and driving forces acting on the molten pool. Moreover, the driving forces acting on the liquid metal in the deposited layer achieved equilibrium and a stable molten pool was acquired only when the arc current was selected appropriately, which resulted in a well forming quality of the deposited part with a lower surface roughness and a higher material utilization rate.

本文对基于双钨电极-丝电极间接电弧（TTWIA）的增材制造的成形特性进行了初步研究。得到了电弧形状、液滴传递行为、熔池温度场和熔池流动状态。结果表明：电弧电流的增大增强了TTWIA电弧的耦合度，促进了液滴与金属丝的分离，有利于液滴的流喷传递；此外，由于电弧温度的升高、液滴所携带的焓的增加以及作用在熔池上的驱动力的增加，熔池的温度和流动性都随着电弧电流的增加而增加。此外，只有选择合适的电弧电流，沉积层中作用于液态金属的驱动力达到平衡，才能获得稳定的熔池，从而使沉积件的成形质量良好，表面粗糙度较低，材料利用率较高。

引用次数: 0

Exploring the edge effect of single crystal silicon in nanoindentation with two indenters: A molecular dynamics investigation 单晶硅在双压头纳米压痕中的边缘效应：分子动力学研究

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-27 DOI: 10.1016/j.vacuum.2024.113891

Rongqi Shen , Duo Li , Yuhai Li

Silicon is an important semiconductor material, and its mechanical properties at the workpiece edges are crucial for its applications at the nanoscale. This article uses a molecular dynamics model with two indenters to study the effect of indenter distance on the edge effect of single-crystal silicon. The simulation results show that as the distance between the two indenters gradually increases from 5 Å, the surface edge of the single crystal silicon workpiece collapses, the side accumulates, and the internal phase transition region and stress region gradually change from a whole to two separate entities. The average value of force Fx first decreases and then increases with the increasing indenter distance. This study elucidates the influence of the distance between the dual indenters on the edge effect of single-crystal silicon nanoindentation, enriching our understanding of the edge effects that occur in the single-crystal Si application process.

硅是一种重要的半导体材料，其工件边缘的机械性能对其在纳米尺度上的应用至关重要。本文采用带有两个压头的分子动力学模型，研究了压头距离对单晶硅边缘效应的影响。仿真结果表明，随着两个压头之间的距离从5 Å开始逐渐增大，单晶硅工件的表面边缘坍塌，边沿累积，内部相变区和应力区逐渐由一个整体变为两个独立的实体。随着压头距离的增加，力Fx的平均值先减小后增大。本研究阐明了双压痕间距对单晶硅纳米压痕边缘效应的影响，丰富了我们对单晶硅应用过程中出现的边缘效应的认识。

引用次数: 0

Photocurrent and electrical properties of SiGe nanocrystals grown on insulator via solid-state dewetting of Ge/SOI for Photodetection and solar cells applications 通过Ge/SOI固态脱湿在绝缘体上生长的SiGe纳米晶体的光电流和电学特性，用于光探测和太阳能电池

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-27 DOI: 10.1016/j.vacuum.2024.113892

A.K. Aladim , Mansour Aouassa , S. Amdouni , Mohammed Bouabdellaoui , Walter B. Pessoa , Mohammed Ibrahim , K.M.A. Saron , Isabelle Berbezier

In this study, we present the photocurrent and electrical characterization of silicon-germanium nanocrystals (SiGe NCs) on an insulator (SiO₂). The SiGe NCs were grown through a hybrid process combining solid-phase dewetting of an ultra-thin silicon-on-insulator (UT-SOI) film with the epitaxial deposition of a thin germanium layer using ultra-high vacuum molecular beam epitaxy (UHV-MBE). These SiGe NCs were successfully integrated into the insulator layer of a metal-insulator-semiconductor (MIS) structure for optoelectronic applications. The enhanced MIS structure, featuring integrated SiGe NCs, exhibited notable transport and optoelectric properties as determined by current-voltage and impedance spectroscopy. The results indicated that the MIS structure functions as a Schottky diode, demonstrating a high rectification ratio (RR) of approximately 1000 and a Schottky barrier height (ϕ_B) of 0.73 eV. Additionally, this structure displayed a broad spectral response in the visible range, with a significant photovoltaic effect. The equivalent circuit of the MIS structure was also derived for an AC signal using impedance spectroscopy. These findings offer a promising scalable method for the monolithic integration and efficient growth of SiGe nanocrystals, paving the way for advancements in self-powered photodetectors and ultrathin solar cells.

在这项研究中，我们介绍了硅锗纳米晶体（SiGe NCs）在绝缘体（SiO2）上的光电流和电学特性。采用固相脱湿的超薄绝缘体上硅（UT-SOI）薄膜和超薄锗外延的超高真空分子束外延（UHV-MBE）相结合的混合工艺生长SiGe NCs。这些SiGe nc成功地集成到金属-绝缘体-半导体（MIS）结构的绝缘体层中，用于光电子应用。集成了SiGe nc的增强MIS结构，通过电流-电压和阻抗谱分析，显示出显著的输运和光电性能。结果表明，MIS结构具有肖特基二极管的功能，具有约1000的高整流比（RR）和0.73 eV的肖特基势垒高度（ϕB）。此外，该结构在可见光范围内具有较宽的光谱响应，具有明显的光伏效应。利用阻抗谱法推导了交流信号的MIS结构的等效电路。这些发现为SiGe纳米晶体的单片集成和高效生长提供了一种有前途的可扩展方法，为自供电光电探测器和超薄太阳能电池的发展铺平了道路。

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