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Severe liver injury and clinical characteristics of occupational exposure to 2-amino-5-chloro-N,3-dimethylbenzamide: A case series
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作者 Meng-Xiao Feng Hua Zou Yuan-Qiang Lu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第2期186-194,共9页
Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning... Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enters the body through the respiratory tract and skin during industrial production.The 2-amino-5-chloro-N,3-dimethylbenzamide poisoning causes multiple-organ dysfunction with a predominance of liver injury.Liver transplantation may be an effective option for patients with severe liver failure.The mechanisms of liver injury induced by 2-amino-5-chloro-N,3-dimethylbenzamide might involve abnormal mitochondrial function and mitophagy. 展开更多
关键词 2-amino-5-chloro-N 3-dimethylbenzamide Poisoning Clinical characteristics Liver injury
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Characteristics and close-range exploration methods of near- Earth asteroid 2016HO_(3)
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作者 He Zhang Fei Li +3 位作者 Linzhi Meng Fuming Zeng Xiaoyu Jia Yu’ang Liu 《Astronomical Techniques and Instruments》 CSCD 2024年第1期42-51,共10页
The characteristics of asteroids are vital parameters for planning asteroid exploration missions.These characteristics have been explored in close range for some typical asteroids,and are summarized in the article.Thi... The characteristics of asteroids are vital parameters for planning asteroid exploration missions.These characteristics have been explored in close range for some typical asteroids,and are summarized in the article.This allows estimates of the characteristics of asteroid 2016HO_(3),the target of the first Chinese asteroid exploration mission,Tianwen 2.We obtain 80 characteristic parameters in 9 categories and analyze their impacts on the mission.By comparing three close-range exploration modes,we provide advantages and disadvantages of each,and propose suitable methods for the exploration of 2016HO_(3).Owing to the weak gravity and small size of 2016HO_(3),a combination of multiple hovering positions and active orbiting is recommended for scientific exploration. 展开更多
关键词 Near-Earth asteroid 2016HO_(3) Tianwen 2 Close-range exploration characteristics
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A simulation study of polarization characteristics of ultrathin CsPbBr3 nanowires with different cross-section shapes and sizes
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作者 杨康 胡回清 +3 位作者 王娇娇 邓玲玲 陆云清 王瑾 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期341-346,共6页
The polarization characteristics of ultrathin CsPbBr3nanowires are investigated. Especially, for the height of crosssection of nanowires between 2 nm and 25 nm, the normalized intensity and polarization ratio ρ of Cs... The polarization characteristics of ultrathin CsPbBr3nanowires are investigated. Especially, for the height of crosssection of nanowires between 2 nm and 25 nm, the normalized intensity and polarization ratio ρ of CsPbBr3nanowires with triangular, square and hexagonal cross-section shapes are compared. The results show that, along with the increase of the height of cross-section, the polarization ratios of these three nanowires decrease until T = 15 nm, and increase afterwards.Also, along with the increase of the cross-section area up to 100 nm~2, the polarization ratios of these three nanowires increase too. In general, for the same height or area, the polarization ratio ρ of these nanowires follows ρhexagon> ρsquare>ρtriangle. Therefore, the nanowire with the hexagonal cross-section should be chosen, where for a cross-section height of 2 nm and a length-height ratio of 20 : 1, the maximal polarization ratio is 0.951 at the longitudinal center of the NW. Further,for the hexagonal NW with a cross-section height of 10 nm, the hexagonal NW with a length-height ratio of 45 : 1 exhibits the maximal polarization ratio at the longitudinal center of the NW. These simulation results predict the feasible size and shape of CsPbBr3nanowire devices with high polarization ratios. 展开更多
关键词 CsPbBr3 NANOWIRE polarization characteristics
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Lie symmetry analysis and invariant solutions for the(3+1)-dimensional Virasoro integrable model
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作者 胡恒春 李雅琦 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期249-254,共6页
Lie symmetry analysis is applied to a(3+1)-dimensional Virasoro integrable model and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with a... Lie symmetry analysis is applied to a(3+1)-dimensional Virasoro integrable model and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with arbitrary functions for the(3+1)-dimensional Virasoro integrable model,including the interaction solution between a kink and a soliton,the lump-type solution and periodic solutions,have been studied analytically and graphically. 展开更多
关键词 (3+1)-dimensional Virasoro integrable model Lie symmetry invariant solutions
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Interaction solutions for the second extended(3+1)-dimensional Jimbo–Miwa equation
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作者 马红彩 毛雪 邓爱平 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期112-121,共10页
Based on the Hirota bilinear method,the second extended(3+1)-dimensional Jimbo–Miwa equation is established.By Maple symbolic calculation,lump and lump-kink soliton solutions are obtained.The interaction solutions be... Based on the Hirota bilinear method,the second extended(3+1)-dimensional Jimbo–Miwa equation is established.By Maple symbolic calculation,lump and lump-kink soliton solutions are obtained.The interaction solutions between the lump and multi-kink soliton,and the interaction between the lump and triangular periodic soliton are derived by combining a multi-exponential function or trigonometric sine and cosine functions with quadratic functions.Furthermore,periodiclump wave solution is derived via the ansatz including hyperbolic and trigonometric functions.Finally,3D plots,2D curves,density plots,and contour plots with particular choices of the suitable parameters are depicted to illustrate the dynamical features of these solutions. 展开更多
关键词 Hirota bilinear method second extended(3+1)-dimensional Jimbo–Miwa equation lump solution interaction solution
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Clinical Characteristics and Prognosis of Patients with Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis According to Serotype: A Retrospective Study of 349 Chinese Patients
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作者 Haifan Xu Miao Feng +2 位作者 Xinqiang Lin Dingxin Zhang Liqun Chen 《Journal of Biosciences and Medicines》 2023年第11期151-169,共19页
Objective: According to clinical phenotypic classification, there is a significant overlap of clinical features between different anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), and disease cl... Objective: According to clinical phenotypic classification, there is a significant overlap of clinical features between different anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), and disease classification based on ANCA subtype helps to differentiate clinical phenotypes. We investigated the clinical features and outcomes of patients based on ANCA serotype classification. Methods: Clinical and laboratory data were collected retrospectively. We compared clinical manifestations and organ involvement based on serotype. The risk factors for death and renal survival were investigated with univariate and multivariate Cox regression models. Results: Patients with MPO-ANCA were predominant, whose median age and lung involvement at diagnosis was higher than that of the PR3-ANCA patients. Compared to the AAV patients without renal involvement, those with renal involvement have older, anemia, low complement C3, and hypoproteinemia, more likely to have cardiovascular and abdominal involvement, and have less lung involvement. Multivariate Cox analysis revealed that age ≥ 65 years (HR = 2.611, p p = 0.019), BVAS ≥ 15 (HR = 1.943, p = 0.001), low C3 (HR = 1.696, p = 0.008), and hypoproteinemia (HR = 1.438, p = 0.044) were associated with mortality. SCR ≥ 500 μmol/L (HR = 13.583, p p = 0.020), low C3 (HR = 1.506, p = 0.049) were independent detrimental factors for renal survival, and immunosuppressive treatment was a protective factor for renal survival (HR = 0.523, p = 0.003). Conclusions: Clinical manifestations varied by AAV categories. Age, SCR, BVAS, low C3 and hypoproteinemia at diagnosis were independent predictors of mortality. BVAS, low C3, SCR at diagnosis and immunosuppressive treatment were independently related to renal survival in ANCA positive patients. 展开更多
关键词 MPO-ANCA PR3-ANCA Associated Vasculitis characteristics Renal Involvement Risk Factors Survival
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Optimization of ITO/V_(2)O_(5)/Alq3/TPBi/BPhen/LiF/Al Layers Configuration for OLED and Study of Its Optical and Electrical Characteristics
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作者 Ritu Sandhya Kattayat +3 位作者 H.K.Subania S.Z.Hashmi Jasgurpreet Singh P.A.Avi 《Semiconductor Science and Information Devices》 2023年第1期3-10,共8页
Nowadays,OLEDs have shown aesthetic potential in smart cards,sensor displays,other electronic devices,sensitive medical devices and signal monitoring etc.due to their wide range of applications like low power consumpt... Nowadays,OLEDs have shown aesthetic potential in smart cards,sensor displays,other electronic devices,sensitive medical devices and signal monitoring etc.due to their wide range of applications like low power consumption,high contrast ratio,speed highly electroluminescent,wide viewing angle and fast response time.In this paper,a highly efficient organic LED ITO/V_(2)O_(5)/Alq3/TPBi/BPhen/LiF/Al with low turn-on voltage and high optically efficiency is presented including electrical and optical characteristics.The simulation of electrical characteristics like current versus applied voltage,current density versus applied voltage,recombination prefactor versus excess carrier density characteristics and optical characteristics like light flux versus current density,light flux versus applied voltage and optical efficiency versus applied voltage has been explained.The physical design,working principle and thickness of different layers along with the process of formation of singlet and triplet excitons are discussed in detail.Here double electron transport layer(ETL),cathode layers are used to enhance the electrical and optical efficiency of OLED.The operating voltage is found to be~3.2 V for the ITO/V_(2)O_(5)/Alq3/TPBi/BPhen/LiF/Al heterostructure based OLED.The designed organic LED has achieved the maximum optical efficiency at 3 V. 展开更多
关键词 OLED ALQ3 BPhen TPBi I-V characteristics
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Study on Wave Field Characteristics and Imaging of Collapse Column in Three-Dimensional Detection with Love Channel Wave Reflected outside the Working Face 被引量:2
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作者 Huachao Sun Huide Zhang +4 位作者 Jinyun Wang Xianzhuang Lv Xin Ding Shiyu Xing Heng Zhang 《Open Journal of Geology》 2020年第11期1027-1039,共13页
The safety accidents caused by collapse column water diversion occur frequently, which has great hidden danger to the safety production of coal mine. Limited by the space of underground, the detection of collapse colu... The safety accidents caused by collapse column water diversion occur frequently, which has great hidden danger to the safety production of coal mine. Limited by the space of underground, the detection of collapse column on the outside of working face has been a difficult problem. Based on this, numerical simulation and imaging research were carried out in this paper. The results indicate that when a seismic source near the roadway is excited, a part of seismic wave propagates along the roadway direction, namely direct P-wave, direct S-wave and direct Love channel wave.<span style="font-family:;" "=""> </span><span style="font-family:Verdana;">When the body waves and Love channel wave propagating to the outside</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">of working face meet the interface of collapse column, the reflected Love channel wave and reflected body waves are generated.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">Reflection </span><span style="font-family:Verdana;">body </span><span style="font-family:Verdana;">waves and direct waves are mixed in time domain, which is difficult to identify in seismic records, while reflected Love channel wave whose amplitude is relatively strong. The </span><span style="font-family:Verdana;">reflected </span><span style="font-family:Verdana;">Love channel wave which has a large interval from other wave trains in the time domain is easily recognizable in seismic record,</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">which</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">makes it suitable for advanced detection of collapse column. The signal-to-noise ratio of X component is higher than that of Y component and Z component. According to the seismic records, polarization filtering was carried out to enhance the effective wave, which removed the interference waves, and the signal was migrated to get the position parameters of collapse column interface, which was basically consistent with the model position.</span> 展开更多
关键词 Reflected Love Channel Wave 3D Numerical Simulation Collapse Column Wave Field characteristics Migration Imaging
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A Three-Dimensional Numerical Model for Predicting the Weld Bead Geometry Characteristics in Laser Overlap Welding of Low Carbon Galvanized Steel 被引量:1
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作者 Kamel Oussaid Abderrazak El Ouafi 《Journal of Applied Mathematics and Physics》 2019年第10期2169-2186,共18页
Laser welding (LW) becomes one of the most economical high quality joining processes. LW offers the advantage of very controlled heat input resulting in low distortion and the ability to weld heat sensitive components... Laser welding (LW) becomes one of the most economical high quality joining processes. LW offers the advantage of very controlled heat input resulting in low distortion and the ability to weld heat sensitive components. To exploit efficiently the benefits presented by LW, it is necessary to develop an integrated approach to identify and control the welding process variables in order to produce the desired weld characteristics without being forced to use the traditional and fastidious trial and error procedures. The paper presents a study of weld bead geometry characteristics prediction for laser overlap welding of low carbon galvanized steel using 3D numerical modelling and experimental validation. The temperature dependent material properties, metallurgical transformations and enthalpy method constitute the foundation of the proposed modelling approach. An adaptive 3D heat source is adopted to simulate both keyhole and conduction mode of the LW process. The simulations are performed using 3D finite element model on commercial software. The model is used to estimate the weld bead geometry characteristics for various LW parameters, such as laser power, welding speed and laser beam diameter. The calibration and validation of the 3D numerical model are based on experimental data achieved using a 3 kW Nd:Yag laser system, a structured experimental design and confirmed statistical analysis tools. The results reveal that the modelling approach can provide not only a consistent and accurate prediction of the weld characteristics under variable welding parameters and conditions but also a comprehensive and quantitative analysis of process parameters effects on the weld quality. The results show great concordance between predicted and measured values for weld bead geometry characteristics, such as depth of penetration, bead width at the top surface and bead width at the interface between sheets, with an average accuracy greater than 95%. 展开更多
关键词 LASER WELDING Low Carbon Galvanized Steel Overlap WELDING Weld BEAD Geometry characteristics 3D Modeling Prediction Model Finite Elements METHOD Taguchi METHOD ANOVA Nd:YAG LASER Source
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Three-dimensional crustal velocity structure and activity characteristics of the Madoi Ms7.4 earthquake in 2021
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作者 Ma Yong Zhang Hai-Jiang +1 位作者 Gao Lei and Chen Zhi-Gang 《Applied Geophysics》 SCIE CSCD 2022年第4期590-602,605,共14页
In this paper,using natural earthquake P-wave arrival time data recorded by the seismic network in the surrounding area of Madoi,the three-dimensional fine P-wave crustal velocity structure at depths above 60 km in th... In this paper,using natural earthquake P-wave arrival time data recorded by the seismic network in the surrounding area of Madoi,the three-dimensional fine P-wave crustal velocity structure at depths above 60 km in the epicenter of the Madoi Ms7.4 earthquake was inverted using the double-difference seismic tomography method.On the basis of the relocation of the source of the aftershock sequence,we summarized the strip-shaped distribution characteristics along the strike of the Jiangcuo fault,revealing the significant heterogeneity of the crustal velocity structure in the source area.Research has found that most of the Madoi Ms7.4 aftershocks were located in the weak area of the high-speed anomaly in the upper crust.The focal depth changed with the velocity structure,showing obvious fluctuation and segmentation characteristics.There was a good correspondence between the spatial distribution and the velocity structure.The high-velocity bodies of the upper crust in the hypocenter area provided a medium environment for earthquake rupture,the low-velocity bodies of the middle crust formed the deep material,and the migration channel and the undulating shape of the high-speed body in the lower crust corroborated the strong pushing action in the region.The results confirmed that under the continuous promotion of tectonic stress in the Madoi area,the high-speed body of the Jiangcuo fault blocked the migration of weak materials in the middle crust.When the stress accumulation exceeded the limit,the Madoi Ms7.4 earthquake occurred.Meanwhile,the nonuniform velocity structure near the fault plane determined the location of the main shock and the spatiotemporal distribution of the aftershock sequence. 展开更多
关键词 Madoi Ms7.4 earthquake double-difference tomography 3D velocity structure seismic activity characteristics
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Three-dimensional velocity structure and tectonic characteristics of earthquake area in Yibin
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作者 Ma Yong Bi Jin-Meng and Gao Lei 《Applied Geophysics》 SCIE CSCD 2019年第3期267-276,394,共11页
In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal par... In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal parameters and three-dimensional(3 D)body-wave high-resolution velocity structures at depths of 0–30 km were retrieved by double-difference tomography.Results show that there is a good correspondence between the spatial distribution of the relocated earthquakes and velocity structures,which were concentrated mainly in the high-velocity-anomaly region or edge of high-velocity region.Velocity structure of P-and S-waves in the Yibin area clearly shows lateral inhomogeneity.The distribution characteristics of the P-and S-waves near the surface are closely related to the geomorphology and geologic structure.The low-velocity anomaly appears at the depth of 15–25 km,which is affected by the lower crust current.The Junlian–Gongxian and Gongxian–Changning earthquake areas,which are the two most earthquake-prone areas in the Yibin region,clearly differ in earthquake distribution and tectonic characteristics.We analyzed the structural characteristics of the Junlian–Gongxian and Gongxian–Changning earthquake areas on the basis of the 3 D bodywave velocity structures in the Yibin region.We found that although most seismicity in the Yibin area is caused by fluid injection,the spatial position of seismicity is controlled by the velocity structures of the middle and upper crust and local geologic structure.Fine-scale 3 D velocity structures in the Yibin area provide important local reference information for further understanding the crustal medium,seismogenic structure,and seismicity. 展开更多
关键词 Yibin area double-difference tomography method 3D P・wave and S・wave velocity structure structural characteristics
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Heteroepitaxial Growth and Heterojunction Characteristics of Voids-Free n-3C-SiC on p-Si(100) 被引量:2
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作者 孙国胜 孙艳玲 +6 位作者 王雷 赵万顺 罗木昌 张永兴 曾一平 李晋闽 林兰英 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第6期567-573,共7页
Highly oriented voids-free 3C-SiC heteroepitaxial layers are grown onφ50mm Si (100) substrates by low pressure chemical vapor deposition (LPCVD).The initial stage of carbonization and the surface morphology of carbon... Highly oriented voids-free 3C-SiC heteroepitaxial layers are grown onφ50mm Si (100) substrates by low pressure chemical vapor deposition (LPCVD).The initial stage of carbonization and the surface morphology of carbonization layers of Si (100) are studied using reflection high energy electron diffraction (RHEED) and scanning electron microscopy (SEM).It is shown that the optimized carbonization temperature for the growth of voids-free 3C-SiC on Si (100) substrates is 1100℃.The electrical properties of SiC layers are characterized using Van der Pauw method.The I-V,C-V,and the temperature dependence of I-V characteristics in n-3C-SiC/p-Si heterojunctions with AuGeNi and Al electrical pads are investigated.It is shown that the maximum reverse breakdown voltage of the n-3C-SiC/p-Si heterojunction diodes reaches to 220V at room temperature.These results indicate that the SiC/Si heterojunction diode can be used to fabricate the wide bandgap emitter SiC/Si heterojunction bipolar transistors (HBT's). 展开更多
关键词 LPCVD voids-free n-3C-SiC/p-Si(100) heterojunction characteristics
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Influence of rapid solidification on Sn-8Zn-3Bi alloy characteristics and microstructural evolution of solder/Cu joints during elevated temperature aging 被引量:2
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作者 赵国际 文光华 盛光敏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期234-240,共7页
The effects of rapid solidification on the microstructure and melting behavior of the Sn-8Zn-3Bi alloy were studied. The evolution of the microstructuraI characteristics of the solder/Cu joint after an isothermal agin... The effects of rapid solidification on the microstructure and melting behavior of the Sn-8Zn-3Bi alloy were studied. The evolution of the microstructuraI characteristics of the solder/Cu joint after an isothermal aging at 150 ℃ was also analyzed to evaluate the interconnect reliability. Results showed that the Bi in Sn-8Zn-3Bi solder alloy completely dissolved in the Sn matrix with a dendritic structure after rapid solidification. Compared with as-solidified Sn-8Zn-3Bi solder alloy, the melting temperature of the rapid solidified alloy rose to close to that of the Sn-Zn eutectic alloy due to the extreme dissolution of Bi in Sn matrix. Meanwhile, the adverse effect on melting behavior due to Bi addition was decreased significantly. The interfacial intermetallic compound (IMC) layer of the solder/Cu joint was more compact and uniform. Rapid solidification process obviously depressed the formation and growth of the interfacial IMC during the high-temperature aging and improved the high-temperature stability of the Sn-8Zn-3Bi solder/Cu joint. 展开更多
关键词 rapid solidification Sn-8Zn-3Bi solder melting characteristic AGING microstructural evolution
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La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂对NO选择性生成NH_(3)的影响
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作者 宋崇林 郑庆贺 +3 位作者 吕誉 崔立峰 李云强 吕刚 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2024年第10期1053-1061,共9页
为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技... 为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技术,此时LNT的作用是将排气中部分NO_(x)转化为NH_(3),为下游的SCR提供还原剂.基于此,制备了LNT催化剂,研究催化剂对NO选择性生成NH_(3)的影响.采用溶胶-凝胶法制备了La_(1-x)Ce_(x)MnO_(3)系列钙钛矿氧化物,并通过分步浸渍法得到了La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)负载型催化剂.利用XRD、H_(2)-TPR、NO-TPD等表征手段研究了钙钛矿氧化物的晶相结构,以及负载型催化剂的还原特性、NO_(x)吸附-脱附性能等物化性质,并且通过H_(2)选择性催化还原NO实验探究了催化剂掺杂Ce对NO转化成NH_(3)的影响.结果表明,Ce掺杂催化剂具有良好的NH_(3)产物选择性,并且显著提高了NO转化率.温度是NO转化和NH_(3)产物选择性生成的决定性因素,而H_(2)和NO体积比是NO转化和NH_(3)产物选择性生成的关键性因素.其中,La_(0.95)Ce_(0.05)MnO_(3)-Ba/Al_(2)O_(3)在低温下催化活性表现最佳,在350℃、H_(2)和NO体积比为5.0时NH_(3)产物选择性为65%,NO转化率为100%.此外,所制备的La_(1-x)Ce_(x)MnO_(3)都形成了钙钛矿型结构,而且Ce掺杂催化剂的大部分Ce离子可以进入到LaMnO_(3)结构中.在催化剂适量掺杂Ce后,H_(2)消耗总面积增大、还原峰的峰值温度降低,表明掺杂Ce改善了催化剂的还原特性;同时NO吸附和脱附面积增大,表明Ce掺杂改变了催化剂的NO_(x)吸附-脱附性能. 展开更多
关键词 La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂 H_(2)选择性催化还原NO NH_(3)产物选择性 NO转化率 晶相结构 还原特性 NO_(x)吸附-脱附
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B/KNO_(3)点火药装药的烤燃特性研究
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作者 伍俊英 尚伊平 +4 位作者 郑富德 杜皓杰 姚雨乐 李钧剑 陈朗 《兵工学报》 EI CAS CSCD 北大核心 2024年第8期2828-2836,共9页
为研究B/KNO_(3)点火药的热安全性,建立多点测温烤燃实验装置,对不同升温速率、不同装药密度条件下的B/KNO_(3)点火药装药进行多点测温烤燃实验,以获得点火药装药发生点火的准确时间与烤燃过程中不同监测点的温度历程。建立B/KNO_(3)点... 为研究B/KNO_(3)点火药的热安全性,建立多点测温烤燃实验装置,对不同升温速率、不同装药密度条件下的B/KNO_(3)点火药装药进行多点测温烤燃实验,以获得点火药装药发生点火的准确时间与烤燃过程中不同监测点的温度历程。建立B/KNO_(3)点火药装药烤燃实验的数值计算模型并进行了数值模拟,计算中考虑了点火药的自热分解反应与相变吸热。通过与实验结果的对比,标定B/KNO_(3)点火药装药的热物性参数和反应动力学参数。研究结果表明:B/KNO_(3)点火药的指前因子为7.763×10^(13)s^(-1),活化能为2.0787×10^(5)J/mol;在点火药装药的烤燃过程中,随着升温速率的减小,点火延期时间逐渐增加,点火区域逐渐向中心移动,点火环境温度逐渐降低;在装药密度变化不太大的情况下,点火药的点火特征差别不大。 展开更多
关键词 B/KNO_(3)点火药 烤燃实验 热安全性 点火特性
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2 cm以上的C-TI-RADS 3类甲状腺结节的临床特点分析
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作者 唐艺峰 王龙龙 +4 位作者 刘益豪 张逸菲 李红强 马润声 殷德涛 《西安交通大学学报(医学版)》 CSCD 北大核心 2024年第1期74-79,共6页
目的统计2 cm以上的中国版甲状腺影像报告及数据系统(C-TI-RADS)3类甲状腺结节的临床特点,并探究其与性别、结节成分、对侧是否有癌、是否弥漫性回声改变、甲状腺过氧化物酶抗体(thyroid peroxidase antibody,TPOAB)、甲状腺球蛋白抗体(... 目的统计2 cm以上的中国版甲状腺影像报告及数据系统(C-TI-RADS)3类甲状腺结节的临床特点,并探究其与性别、结节成分、对侧是否有癌、是否弥漫性回声改变、甲状腺过氧化物酶抗体(thyroid peroxidase antibody,TPOAB)、甲状腺球蛋白抗体(anti-thyroglobulin antibodies,TGAB)等的相关性。方法回顾性分析2022年9月-2023年3月我科收治的甲状腺超声C-TI-RADS 3类且最大直径≥2 cm的94例甲状腺结节患者(均接受细胞病理和/或组织病理检查)的临床病理学信息。统计TBSⅠ类、良性、低风险肿瘤、恶性的比例,并比较性别、结节成分、对侧是否有癌、是否弥漫性回声改变、TPOAB、TGAB等临床特点在良性、低风险肿瘤、恶性三组中的比例有无统计学差异。结果排除7例TBSⅠ类患者,87例结节病理明确患者中,良性72例(细胞学38例、组织学34例)、低风险肿瘤5例(细胞学2例、组织学3例)、恶性10例(PTC 8例、FTC 1例、MTC 1例)。不同病理类型之间,结节成分(囊实性/实性)组间差异具有显著性,差异有统计学意义(χ^(2)=10.369,P=0.006);性别、是否弥漫性回声改变、对侧是否有癌、TPOAB、TGAB组间差异无统计学意义(P均>0.05)。进一步分析结节成分与病理类型的关系,结果表明,低风险肿瘤相对于良性结节实性比例更高,差异有统计学意义(χ^(2)=9.571,P=0.002);而恶性结节相对于低风险肿瘤(χ^(2)=2.143,P=0.143),恶性结节相对于良性结节(χ^(2)=2.165,P=0.141)囊实性比例差异均无统计学意义。结论虽然各种版本的甲状腺影像报告与数据系统均将TI-RADS 3级结节认定为良性可能,但恶性结节在C-TI-RADS 3类甲状腺结节中仍占一定比例,需要重视诸如囊实性结节、甲状腺滤泡性肿瘤、甲状腺髓样癌等超声征象不典型的甲状腺结节。在评估结节良恶性时,超声引导下细针穿刺细胞病理学检查是必要的,需要重视标本不满意或无法诊断的情况,提高诊断的准确性。 展开更多
关键词 中国版甲状腺影像报告及数据系统(C-TI-RADS)3 甲状腺结节 临床特点
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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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放电等离子体烧结BaTiO_(3-x)Bi(Ni_(0.5)Zr_(0.5))O_(3)陶瓷的介电和阻抗性能
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作者 肖长江 马金明 张群飞 《材料工程》 EI CAS CSCD 北大核心 2024年第5期203-211,共9页
采用传统固相反应法合成BaTiO_(3-x)Bi(Ni_(0.5)Zr_(0.5))O_(3)粉体和放电等离子体烧结技术制备BaTiO_(3-x)Bi(Ni_(0.5)Zr_(0.5))O_(3)陶瓷,研究陶瓷的晶体结构、微观形貌、介电和阻抗性能。结果表明:BaTiO_(3)-0.10Bi(Ni_(0.5)Zr_(0.5)... 采用传统固相反应法合成BaTiO_(3-x)Bi(Ni_(0.5)Zr_(0.5))O_(3)粉体和放电等离子体烧结技术制备BaTiO_(3-x)Bi(Ni_(0.5)Zr_(0.5))O_(3)陶瓷,研究陶瓷的晶体结构、微观形貌、介电和阻抗性能。结果表明:BaTiO_(3)-0.10Bi(Ni_(0.5)Zr_(0.5))O_(3)陶瓷具有钙钛矿型,晶体结构为赝立方相,晶粒尺寸约为0.64μm,密度为5.81 g/cm^(3),最大介电常数为7149,且随频率升高相变温度向高温移动。在1 kHz下,BaTiO_(3)-0.10Bi(Ni_(0.5)Zr_(0.5))O_(3)陶瓷的ln(1/ε-1/ε_(m))与ln(T-T_(m))的拟合曲线斜率为1.61,在-41~169℃内,Δε/ε_(25℃)≤±15%,表明样品有良好的温度稳定性。此外,随温度和频率的升高,材料的阻抗降低,在50℃下,当频率为100 Hz时,电阻为2.33×10~6Ω,离子电导率为10^(-8)S/cm。 展开更多
关键词 BaTiO_(3-x)Bi(Ni_(0.5)Zr_(0.5))O_(3) 放电等离子体烧结 赝立方相 介电性能 弛豫特性 阻抗
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粮草双高型大麦新品种皖饲麦3号的选育及栽培技术
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作者 赵斌 王瑞 +3 位作者 季昌好 孙皓 朱斌 陈晓东 《大麦与谷类科学》 2024年第4期76-79,共4页
皖饲麦3号是安徽省农业科学院作物研究所采用系谱法选育而成的粮草双高型饲用大麦新品种。2018—2020年度参加安徽省多点联合鉴定,平均产量达480.64 kg/667 m^(2),比对照西引二号增产10.42%。2023年通过农业农村部非主要农作物品种登记... 皖饲麦3号是安徽省农业科学院作物研究所采用系谱法选育而成的粮草双高型饲用大麦新品种。2018—2020年度参加安徽省多点联合鉴定,平均产量达480.64 kg/667 m^(2),比对照西引二号增产10.42%。2023年通过农业农村部非主要农作物品种登记,登记号:GPD大麦(青稞)(2023)340003。皖饲麦3号为春性多棱皮大麦,茎秆粗壮,分蘖力较好,生育期187 d左右,株高90 cm左右,千粒质量31 g左右,籽粒蛋白质含量(质量分数,下同)10.31%,淀粉含量632.6 g/kg,β-葡聚糖含量5.01%,综合农艺性状较好,抗倒性强。为充分发挥该品种在安徽省沿淮、江淮地区饲料大麦生产中的作用,系统介绍了其选育过程、特征特性,并提出了以收获青饲草、青贮饲料和籽粒为不同目的的配套高产栽培技术。 展开更多
关键词 粮草双高 大麦 皖饲麦3 品种特性 栽培技术
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YTH结构域家族蛋白2和叉头蛋白转录因子3在肺腺癌中的表达关系研究
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作者 杨睿 李占江 陈腾飞 《安徽医药》 CAS 2024年第4期764-767,I0004,共5页
目的 分析YTH结构域家族蛋白2(YTHDF2)及叉头蛋白转录因子3(FOXO3)在肺腺癌病人中的表达及与预后的关系。方法 收集2020年1月至2021年5月在郑州大学第一附属医院行手术治疗的肺腺癌病人癌组织及对应的癌旁组织(距离癌组织5 cm以上)80对... 目的 分析YTH结构域家族蛋白2(YTHDF2)及叉头蛋白转录因子3(FOXO3)在肺腺癌病人中的表达及与预后的关系。方法 收集2020年1月至2021年5月在郑州大学第一附属医院行手术治疗的肺腺癌病人癌组织及对应的癌旁组织(距离癌组织5 cm以上)80对,收集病人临床病理资料;利用癌症基因组图谱(TCGA)数据库查询YTHDF2、FOXO3基因在肺腺癌中的表达水平;采用免疫组织化学法检测YTHDF2、FOXO3蛋白在肺腺癌组织中的表达情况;分析YTHDF2、FOXO3蛋白水平与肺腺癌病人临床病理资料的关系;分析肺腺癌中YTHDF2与FOXO3基因表达水平的相关性;对病人进行为期3年的随访,分析病人3年累积生存率。结果 YTHDF2、FOXO3蛋白在肺腺癌组织中的高表达率分别为34.00%、26.00%,明显低于癌旁正常组织中79.48%、61.54%(P<0.05)。YTHDF2蛋白表达情况与肺腺癌病人年龄、淋巴结转移和分化程度相关(P<0.05);与TNM分期、性别无关(P>0.05);FOXO3蛋白表达情况与肺腺癌病人性别和分化程度相关(P<0.05);肺腺癌组织中YTHDF2蛋白高表达组和低表达组病人3年累积生存率分别为53.30%、14.00%,经log-rank比较,差异有统计学意义(P<0.05);FOXO3蛋白高表达组和低表达组病人3年累积生存率分别为64.50%、12.20%,经Log-Rank比较,差异有统计学意义(P<0.05)。结论 YTHDF2、FOXO3在肺腺癌组织中均低表达,与病人肿瘤分化程度及3年累积生存率有关,有望成为评估肺腺癌病人预后的生物标志物。 展开更多
关键词 非小细胞肺 肺腺癌 YTH结构域家族蛋白2 叉头蛋白转录因子3 临床病理特征 累积生存率
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