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高等学校化学学报 2024年第3期45卷 47-54页

作者：李敏贺姗姗王宏宇庄家莹金永日李绪文郑州轻工业大学食品与生物工程学院郑州450001 吉林大学化学学院长春130012

为评估香烟烟气中杂环胺的暴露水平,建立了一种基于低共熔溶剂/无机盐双水相萃取-UPLC法测定吸烟者尿液中5种杂环胺(IQ,IQ[4,5-b],Harman,Norharman和Phe-P-1)的方法.制备了7种以氯化胆碱(ChCl)为氢键受体的低共熔溶剂,并对其进行了表征... 详细信息

为评估香烟烟气中杂环胺的暴露水平,建立了一种基于低共熔溶剂/无机盐双水相萃取-UPLC法测定吸烟者尿液中5种杂环胺(IQ,IQ[4,5-b],Harman,Norharman和Phe-P-1)的方法.制备了7种以氯化胆碱(ChCl)为氢键受体的低共熔溶剂,并对其进行了表征;系统考察了影响萃取效率的主要参数,并将该方法与其它方法进行了对比研究.结果表明,在最佳提取条件下,杂环胺(HAAs)的回收率为81.9%~106.2%,日内和日间精密度分别低于2.9%和3.2%,检出限和定量限分别为0.020~0.097 ng/g和0.19~0.39 ng/g.该方法具有操作简单、环境友好及单样品成本低等特点,为尿液中杂环胺的检测提供了一种新方法,在生物样品检测领域具有良好的开发与应用价值.

关键词：杂环胺低共熔溶剂双水相萃取尿液

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Magnetic Resonance Imaging Manifestations in 13 Cases of Seminal Vesicle Tuberculosis

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INFECTION AND DRUG RESISTANCE 2023年 16卷 6871-6879页

作者： Gan, Wei Bi, Yan Fu, xuwen Wei, Jialu Qi, Min he, Jintang Li, Xiang Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept Radiol Kunming 650041 Yunnan Peoples R China Peoples Hosp Lincang Dept Radiol Lincang 677000 Yunnan Peoples R China Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept Surg Kunming 650041 Yunnan Peoples R China

Objective: This study aimed to examine the radiographic manifestations of seminal vesicle tuberculosis (SVT) on magnetic resonance imaging to gain a deeper understanding of this disease. Methods: The clinical symptoms, general conditions, relevant laboratory tests and radiological data of 13 patients diagnosed with SVT were collected through bacteriological examination. A descriptive analysis was used to explore the composition ratio and rate values of the collected data. Results: All 13 cases (100.0%) showed isointense signals on T1WI and hypointense signals on T2WI in the affected seminal vesicles, with the disappearance of the multi-chambered high signal on T2WI in normal seminal vesicles. Eight cases (61.5%) showed diffusion restriction on DWI of the affected seminal vesicle and significant enhancement on the contrast scan, whereas five cases (38.5%) showed unrestricted diffusion and mild enhancement on the contrast scan. Patients with significant enhancements exhibited higher counts and neutrophil percentages than patients with mild enhancements, with statistically significant differences (Z = 2.196, P = 0.030;Z = 2.781, P = 0.003, respectively). The counts and percentage of lymphocytes, CD3(+)T cells and CD4(+)T cells were significantly lower in patients with significant enhancements than in those with mild enhancements, with statistically significant differences (Z = -2.196, P = 0.030;Z = -2.928, P = 0.002;Z = -2.928, P = 0.002;Z = -2.928, P = 0.002, respectively). Patients with significant enhancements were more likely to have active pulmonary tuberculosis than those with mild enhancements, with a statistically significant difference (P = 0.035). Conclusion: Magnetic resonance imaging reveals distinct radiographic features of SVT, and variations in imaging presentations can indicate a patient's immune status.

关键词： seminal vesicle tuberculosis magnetic resonance imaging genitourinary tuberculosis

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含铜镍尾矿重金属溶出特性试验研究

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材料与冶金学报 2019年第2期18卷 147-152页

作者：夏瑜冯泽珅张清孙桂容张淳关曙雷何绪文中国矿业大学(北京)化学与环境工程学院北京100083

本研究以位于我国东北典型铜镍矿区为研究对象,对其进行尾矿重金属溶出特性分析,通过静态浸出实验研究尾矿粒径和固液比对尾矿中镍(Ni)释放浓度及溶液pH的影响;并研究模拟酸雨条件下尾矿中Ni和铜(Cu)的溶解释放规律;此外,也分析了微生... 详细信息

本研究以位于我国东北典型铜镍矿区为研究对象,对其进行尾矿重金属溶出特性分析,通过静态浸出实验研究尾矿粒径和固液比对尾矿中镍(Ni)释放浓度及溶液pH的影响;并研究模拟酸雨条件下尾矿中Ni和铜(Cu)的溶解释放规律;此外,也分析了微生物对尾矿中重金属的溶出特性的影响.结果表明:在初始pH=7. 0的浸出液中,尾矿中的Ni在第1天就释放得较为完全,其质量浓度达到0. 85～1. 73 mg/L。减小尾矿粒径会增加Ni释放量,固液比过高会减小Ni的浸出;模拟酸雨(pH=4. 0和6. 0)条件下,淋溶液pH值相对较稳定,说明尾矿的缓冲能力较强,低pH条件利于Ni和Cu的溶出.静态浸出和动态淋溶实验初期,Ni的质量浓度基本高于《污水综合排放标准》(GB8978-1996)中的Ni排放限值(1. 0 mg/L),说明铜镍尾矿具有污染水环境的风险.微生物溶出试验结果表明:35 d后Ni和Cu浸出率达到了38. 4%和32. 7%,较酸浸条件下分别提高了74. 5%和28. 7%,说明微生物作用会加剧重金属Ni和Cu的释放,从而增加其环境风险.

关键词：含铜镍尾矿重金属静态浸出动态淋溶

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Research and Optimization of Process Parameters for Internal Thread Forming Based on Numerical Simulation and Experimental Analysis

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MATERIALS 2022年第9期15卷 3160-3160页

作者： he, Qiang Jiang, Yuxiang Jing, xuwen Jiang, Yonggang Zhou, Honggen Fu, Bofeng Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212000 Jiangsu Peoples R China CSSC Huangpu Wenchong Shipbldg Co Ltd Guangzhou 510715 Peoples R China Shanxi Diesel Engine Heavy Ind Co Ltd Xian 713100 Peoples R China

In order to improve the forming quality of extruded thread, finite element analysis and experimental research are combined to reduce the two keys that affect thread quality in the machining process-extrusion torque and extrusion temperature. The effects of different processing parameters on the extrusion torque and temperature are obtained by numerical simulation, including the bottom hole diameter of the workpiece, the machine tool speed, and the lubrication medium. For the purpose of reducing extrusion torque and temperature, the process parameters for internal thread forming are further optimized by orthogonal design. It is determined that when machining the M22 x 2 internal thread on the connecting rod of the marine diesel engine made of 42CrMo4 steel, the bottom hole diameter of the workpiece should be null 21.20 mm, the speed of the machine tool should be 40 RPM, and the lubricating medium should be PDMS polydimethylsiloxane coolant. Compared to before optimization, the maximum extrusion torque and the maximum extrusion temperature are reduced by 19.27% and 15.07%, respectively. On the premise of ensuring the thread connection strength, the height of the thread tooth is reduced by 0.052 mm, and the surface condition of the thread is improved. The surface microhardness at the root, top, and side of the thread increases by about 5 HV0.2, and the depth of the hardened layer increases by 0.05 mm. The results show that the quality of the optimized thread is higher.

关键词： internal thread thread forming numerical simulation physical test parameter optimization

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Enhanced aqueous stability and radiative-charge-transfer of CsPbBr3/Ag2S perovskite nanocrystal hybrids

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JOURNAL OF ELECTROANALYTICAL CheMISTRY 2020年第0期858卷 113835-000页

作者： Fu, Kena he, Yupeng Zhang, Bin Gao, xuwen Zou, Guizheng Shandong Univ Sch Chem & Chem Engn Jinan 250100 Peoples R China

A convenient strategy to enhance the aqueous stability and radiative-charge-transfer of perovskite nanocrystals (PNCs) is developed via hybriding CsPbBr3 PNCs with Ag2S nanoparticles, which is conducted by directly decomposing silver diethyldithiocarbamate in CsPbBr3 PNCs crude. The obtained CsPbBr3-Ag2S hybrids are aqueous stable, and exhibit obviously enhanced aqueous photoluminescence (PL) with a quantum yield up to 82%in pure water as well as boosted electrochemical response for charge injection and 9-fold enhanced electrochemiluminescence (ECL) than CsPbBr3 PNCs in aqueous electrolyte. Both PL and ECL spectra of CsPbBr3-Ag2S hybrids are almost identical to the PL spectrum of CsPbBr3PNCs, indicating radiative-charge-transfer within CsPbBr3-Ag2S hybrids only occurs in CsPbBr3 segment. Annihilation ECL demonstrates that all the charges injected onto CsPbBr3-Ag2S hybrids at the redox potentials of Ag2S segment can be efficiently transferred into CsPbBr3 segment to enhance radiative-charge-transfer. This strategy is promising for the application of PNCs as well as the developing of novel electrochemiluminophores. (C) 2020 Elsevier B.V. All sights reserved.

关键词： Electrochemiluminescence CsPbBr3-Ag2S hybrids Aqueous stability Radiative charge transfer

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Initial Assessment of LEO-Augmented GPS RTK in Signal-Degraded Environment

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2020年第7期E103A卷 942-946页

作者： Hu, Weisheng Hou, Huiling Xie, Zhuochen Liang, xuwen he, Xiaohe Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai Peoples R China Univ Chinese Acad Sci Beijing Peoples R China Chinese Acad Sci Shanghai Engn Ctr Microsatellites Shanghai Peoples R China ShanghaiTech Univ Sch Informat Sci & Technol Shanghai Peoples R China

We simulate some scenarios that 2/3 LEO satellites enhance 3/4/5 GPS satellites, to assess LEO-augmented GPS RTK positioning in signal-degraded environment. The e ffects of LEO-augmented GPS RTK in terms of reliabilit... 详细信息

关键词： LEO-augmented RTK signal-degrade environment DIA

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运动疗法联合语言康复训练治疗语言发育迟缓患儿的临床效果

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浙江医学 2024年第2期46卷 187-190页

作者：鲁旭文何莉丽余姚市妇幼保健院儿童保健科 315400

目的探讨运动疗法联合语言康复训练对语言发育迟缓患儿的临床效果及对语言发育能力和社会生活能力的影响。方法选取2022年5月至2023年1月在余姚市妇幼保健院就诊的语言发育迟缓患儿70例为研究对象,采用随机数字表法分为观察组35例和对照... 详细信息

目的探讨运动疗法联合语言康复训练对语言发育迟缓患儿的临床效果及对语言发育能力和社会生活能力的影响。方法选取2022年5月至2023年1月在余姚市妇幼保健院就诊的语言发育迟缓患儿70例为研究对象,采用随机数字表法分为观察组35例和对照组35例。对照组患儿采用语言康复训练,观察组患儿在语言康复训练基础上联合运动疗法。两组干预时间均为8周。比较两组干预疗效、治疗前后Gesell发育量表评分和社会生活能力变化。结果观察组患儿总有效率为94.29%,高于对照组的74.29%,差异有统计学意义(P<0.05)。两组患儿治疗后精细动作、适应能力、语言能力、个人-社交行为和大运动评分均高于治疗前,差异均有统计学意义(均P<0.05);观察组患儿治疗后上述评分均高于对照组,差异均有统计学意义(均P<0.01)。两组患儿治疗后运动、交往、作业操作和参加集体活动评分均高于治疗前,差异均有统计学意义(均P<0.05);观察组患儿治疗后上述评分均高于对照组,差异均有统计学意义(均P<0.01)。结论运动疗法联合语言康复训练对语言发育迟缓患儿的临床效果显著,且可改善患儿语言发育能力,提高患儿社会生活能力。

关键词：运动疗法语言康复训练语言发育迟缓语言发育能力社会生活能力

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Effect of stamping deformation on microstructure and properties evolution of an Al-Mg-Si-Cu alloy for automotive panels

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JOURNAL OF MATERIALS SCIENCE 2017年第10期52卷 5569-5581页

作者： Yang, Mingjun Liu, Siliang he, xuwen Wang, Jiong Kong, Yi Zhao, Pizhi Li, Kai Du, Yong Cent S Univ State Key Lab Powder Met Changsha 410083 Peoples R China Suzhou Res Inst Nonferrous Met Dept Fabricat Proc & Technol Aluminum Alloys Suzhou 215026 Peoples R China CHINALCO Res Inst Sci & Technol Dept Fabricat Proc & Technol Aluminum Alloys Beijing 100082 Peoples R China Cent S Univ Inst Mat Microstruct Changsha 410083 Peoples R China

The effect of 5 % tensile deformation, which simulates the stamping process of Al-Mg-Si-Cu automotive outer panels, on the microstructural evolution during age strengthening, has been investigated. In addition, its benefit on key mechanical properties including hardness, yield strength, ductility, and corrosion resistance has been linked to the microstructural features. It was found that the aging precipitation sequence, SSSS -> clusters and G.P. zones -> beta aEuro(3) -> beta' + Q' -> Q, was not influenced by the dislocations introduced through the stamping deformation prior to aging. On the other hand, stamping deformation could promote the formation of precipitates and refine the precipitates because of the enhanced heterogeneous nucleation and the accelerated precipitation kinetics, leading to superior strength of the alloy at the early stage. Meanwhile, the larger amount of Cu incorporated into nanoprecipitates leads to better intergranular corrosion resistance of the stamped alloy compared with the unstamped one. Due to the reduction in free Si amount at grain boundaries, the formation of fine subgrain structures and the increase of dislocation accumulation, the ductility of the stamped alloy was increased.

关键词： ALUMINUM-magnesium-silicon alloys DEFORMATIONS (Mechanics) METAL microstructure TENSILE strength DISLOCATIONS in crystals

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Development of hard X-ray spectrometer with full digital data acquisition for runaway electron studies at HL-2M

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JOURNAL OF INSTRUMENTATION 2023年第2期18卷 T02006页

作者： Cheng, Shikui Zhang, Jie Zhang, Yipo he, Li Xu, Hongbing Zhu, Yuxuan Zhan, xuwen Shi, Zhongbing Zhong, Wulv Southwestern Inst Phys Chengdu 610041 Sichuan Peoples R China Chengdu Univ Technol Coll Nucl Technol & Automat Engn Chengdu 610059 Sichuan Peoples R China

The development of hard X-ray (HXR) spectrometers with full digital data acquisition for runaway electron studies on the HL-2M tokamak is presented. Consisting of large-sized NaI:Tl detectors and high-performance multichannel analyzers, this system can realize the measurement of HXR with energies ranging from 0.5 to 10 MeV, and spectrum temporal resolution of 1 ms. An average energy resolution of 56 keV at 662 keV has been achieved at counts rates of about 100 kcps. The spectra data is acquired by a digital-based data acquisition system with fast digitization and software signal processing technology. The energy calibrations are performed by using several radioisotope gamma-ray sources, and the detection efficiencies are simulated by MCNP code. First experimental results from HL-2M Ohmic discharges are presented in this paper.

关键词： Nuclear instruments and methods for hot plasma diagnostics Gamma detectors (scin- tillators CZT HPGe HgI etc) X-ray detectors

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Research on the Performance of Multi-GNSS Medium Length Baseline RTK with LEO-Augmented

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2020年第5期E103A卷 780-784页

作者： Hu, Weisheng Liang, xuwen Hou, Huiling Xie, Zhuochen he, Xiaohe Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai Peoples R China Chinese Acad Sci Shanghai Engn Ctr Microsatellites Shanghai Peoples R China Univ Chinese Acad Sci Beijing Peoples R China ShanghaiTech Univ Sch Informat Sci & Technol Shanghai Peoples R China

In this letter, we simulate GNSS/LEO measurements and propose a process strategy for LEO-augmented GNSS medium length baseline RTK. Experiments show that, the performance of GNSS medium length baseline RTK can be significantly improved by introducing LEO satellites. The convergence speed of LEO-augmented GPS or BDS float solution maybe better than GPS/BDS combined under the conditions of similar satellite geometry. Besides, the RMS error of fixed solutions are improved to better than 4 cm from sub-decimeter level.

关键词： multi-GNSS LEO-augmented medium length baseline RTK

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