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Structural analysis of [Bmim]_2CuCl_4 ionic liquids in the presence of water and ethanol by XAFS technique

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Science China Chemistry 2015年第4期58卷 716-721页

作者： Fangling Jiang cheng Li Haiying Fu Yaxing Wang Xiaojing Guo Guozhong wu Shanghai Institute of Applied Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The structure of [Bmim]2CuCl4 ionic liquids （Bmim： 1-butyl-3-methylimidazolium） with different ratios of H2O and C2H5OH was investigated using X-ray absorption fine structure （XAFS） technique. In this study, XAFS was employed to directly probe the conformational variations of copper ions in [Bmim]2CuCl4 with the addition of either water or ethanol. XAFS analysis confirmed that the structure of ionic liquids gradually transformed from tetrahedral to octahedral configuration with the increase in ratio of H2O. Our results also showed that water molecules coordinated with the copper ions of [Bmim]2CuCl4, leading to the conformational change in ionic liquids. However, the XAFS spectra of [Bmim]zCuCIa/C2H5OH indicated no coordination of anhydrous ethanol with the copper ions of [Bmim]2CuC14. The structure of [Bmim]2CuCl4 ionic liquids is maintained as the tetrahedral configuration in presence of ethanol. Therefore, anhydrous ethanol causes little variation in the structure of ionic liquids and it is a good solvent for the dilution of ionic liquids.

关键词： ionic liquids water ethanol XAFS

胃蛋白酶原测定检查在儿童消化性溃疡中诊断价值

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重庆医学 2024年第19期53卷 2949-2953,2959页

作者：王一张俐吴楠陈桂英北京儿童医院黑龙江医院/哈尔滨医科大学附属第六医院江南院区消化内科哈尔滨150010 北京儿童医院黑龙江医院/哈尔滨医科大学附属第六医院江南院区儿童保健科哈尔滨150010 北京儿童医院黑龙江医院/哈尔滨医科大学附属第六医院江南院区急诊科哈尔滨150010

目的探讨胃蛋白酶原(PG)诊断儿童消化性溃疡的价值。方法选取2019年7月至2024年1月因恶心、呕吐、腹痛、消化道出血等消化道症状于该院完成胃镜检查的855例患儿为研究对象,根据胃镜检查结果分为健康体检组(n=223)、慢性胃炎组(n=418)、... 详细信息

目的探讨胃蛋白酶原(PG)诊断儿童消化性溃疡的价值。方法选取2019年7月至2024年1月因恶心、呕吐、腹痛、消化道出血等消化道症状于该院完成胃镜检查的855例患儿为研究对象,根据胃镜检查结果分为健康体检组(n=223)、慢性胃炎组(n=418)、慢性胃炎合并十二指肠球炎组(n=168)及胃溃疡及十二指肠球部溃疡组(消化性溃疡组,n=46)。共503例研究对象完善13 C呼气试验并根据结果分为幽门螺杆菌(Hp)阳性和Hp阴性,采取乳胶免疫比浊法检测所有研究对象血清PGⅠ、PGⅡ、PGⅠ/PGⅡ水平,分析该项指标在不同年龄、不同胃部疾病中的差异,以及在消化性溃疡中的诊断价值。结果消化性溃疡组女性患儿占比明显低于其他3组,差异有统计学意义(P12岁,差异有统计学意义(P12岁组,12岁组,差异有统计学意义(P<0.05)。与健康体检组比较,慢性胃炎组PGⅠ水平升高,慢性胃炎合并十二指肠球炎组PGⅠ、PGⅡ升高,PGⅠ/PGⅡ降低,消化性溃疡组PGⅠ、PGⅡ升高,PGⅠ/PGⅡ降低,差异有统计学意义(P<0.05)。与慢性胃炎组比较,慢性胃炎合并十二指肠球炎组PGⅠ/PGⅡ降低,消化性溃疡组PGⅠ、PGⅡ升高,PGⅠ/PGⅡ降低,差异有统计学意义(P<0.05)。与慢性胃炎合并十二指肠球炎组比较,消化性溃疡组PGⅠ、PGⅡ升高,PGⅠ/PGⅡ降低,差异有统计学意义(P<0.05)。PGⅠ和PGⅡ预测消化性溃疡的AUC分别为0.689、0.785。以Youden指数最大时作为截断值,当PGⅠ为69.25μg/L时,其Youden指数达到最大值,消化性溃疡诊断灵敏度为67.4%,特异度为72.3%;当PGⅡ为12.25μg/L时,其Youden指数达到最大值,消化性溃疡诊断灵敏度为71.7%,特异度为76.1%。与Hp阴性比较,慢性胃炎组和慢性胃炎合并十二指肠球炎组Hp阳性PGⅠ和PGⅡ升高,PGⅠ/PGⅡ降低,消化性溃疡组Hp阳性PGⅠ/PGⅡ降低,差异有统计学意义(P<0.05)。结论PG可用于诊断儿童消化性溃疡。

关键词：胃功能测定胃蛋白酶原血清学检查儿童消化性溃疡幽门螺杆菌

Proton linac-based therapy facility for ultra-high dose rate (FLASH) treatment

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Nuclear Science and Techniques 2021年第4期32卷 1-9页

作者： Wen-cheng Fang Xiao-Xia Huang Jian-Hao Tan Chao-Peng Wang cheng-cheng Xiao yi-Xing Lu Yu Zhang Yu-Qing Yang yi-Ming Xu Han-Yu Gong Jun-Qiang Zhang Shao-Peng Zhong Zhen-Tang Zhao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China Shanghai APACTRON Particle Equipment Company Limited Shanghai 201800China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

As an advanced treatment method in the past five years,ultra-high dose rate(FLASH)radiotherapy as a breakthrough and milestone in radiotherapy development has been verified to be much less harmful to healthy tissues in different *** treatments require an instantaneous dose rate as high as hundreds of grays per second to complete the treatment in less than 100 *** proton therapy facilities with the spread-out of the Bragg peak formed by different energy layers,to our knowledge,cannot easily achieve an adequate dose rate for FLASH treatments because the energy layer switch or gantry rotation of current facilities requires a few seconds,which is relatively long.A new design for a therapy facility based on a proton linear accelerator(linac)for FLASH treatment is proposed *** is designed under two criteria:no mechanical motion and no magnetic field *** new therapy facility can achieve an ultrahigh dose rate of up to 300 Gy/s;however,it delivers an instantaneous dose of 30 Gy within 100 ms to complete a typical FLASH *** design includes a compact proton linac with permanent magnets,a fast beam kicker in both azimuth and elevation angles,a fixed gantry with a static superconducting coil to steer proton bunches with all energy,a fast beam scanner using radio-frequency(RF)deflectors,and a fast low-level RF *** relevant principles and conceptual proposals are presented herein.

关键词： Proton therapy FLASH Proton linac Deflector Superconducting coil Fast scanner

无人机辅助MEC系统中面向用户公平性的三维部署和卸载优化

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计算机系统应用 2024年第1期33卷 157-166页

作者：林诚章吴涛周启钊陈曦成都信息工程大学计算机学院成都610225 西南民族大学计算机科学与工程学院成都610225

针对无人机辅助移动边缘计算系统存在的用户公平性不足问题,本文提出了一种面向用户公平性的三维部署和卸载优化算法.该算法综合考虑用户匹配、无人机三维部署、计算资源分配、卸载因子对系统总时延及用户公平性的影响,建立了一个最小... 详细信息

针对无人机辅助移动边缘计算系统存在的用户公平性不足问题,本文提出了一种面向用户公平性的三维部署和卸载优化算法.该算法综合考虑用户匹配、无人机三维部署、计算资源分配、卸载因子对系统总时延及用户公平性的影响,建立了一个最小化系统总时延的多元优化问题,并针对该问题提出了一种两阶段联合优化算法,其中第1阶段使用带有平衡约束的聚类算法解决用户匹配和无人机的水平部署问题,第2阶段使用凸优化算法迭代求解无人机高度部署,资源分配和卸载因子优化问题.实验结果表明,与4种基准算法相比,所提算法在系统总时延和用户公平性两方面具有更好的性能.

关键词：无人机移动边缘计算计算卸载三维部署凸优化

Effects of sediment dredging on water quality and zooplankton community structure in a shallow of eutrophic lake

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Journal of Environmental Sciences 2010年第2期22卷 218-224页

作者： Shiyang Zhang Qiaohong Zhou Dong Xu Jidong Lin Shuiping cheng Zhenbin wu State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate School of Chinese Academy of Sciences Beijing 100049 China wuhan Water Authority Wuhan 430014 China

Effects of suction dredging on water quality and zooplankton community structure in a shallow of eutrophic lake, were evaluated. The results showed that a decreasing trend for levels of phosphorus, organic matter, total suspended solids, Chlorophyll a and Secchi transparency in the water column was found, while levels of water depth, electrical conductivity, total dissolved solids and NO3^--N concentration increased markedly post-dredging. The effects of dredging on dissolved oxygen, pH value and temperature were almost negligible. The zooplankton community structure responded rapidly to the environmental changes caused mainly by dredging. As a result, the abundance of rotifers decreased, while the density of zooplanktonic crustaceans increased markedly. The representative taxa were Brachionus angularis, B. budapestinensis, B. diversicornis, Synchaeta spp. and Neodiaptomus schmackeri. A distinct relationship between zooplankton taxa composition and their environment, unraveled by a redundancy analysis, indicating that the measured environment contributed to the variations in the zooplankton community structure to some extent. The first four synthetic environmental variables explained 51.7% of the taxonomic structure. Therefore, with the reduction of internal nutrient load and a shift in dominance by less eutrophic species, it inferred that dredging might be one of effective measures for environmental improvements of such lakes.

关键词： zooplankton community structure redundancy analysis internal nutrient load

Raman Scattering in Coherently Prepared Atomic System

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Chinese Physics Letters 2001年第11期18卷 1473-1475页

作者： LIN Fu-cheng Joogmin Lee Yongjoo Rhee Jonghoon yi Hyunmin Park Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesP.O.Box 800-211Shanghai 201800 Laboratory for Quantum Optics Korea Atomic Energy Research InstituteTaejon 305-600Korea

Atoms in the coherent superposition state prepared by a pulse pair are used as a novel optical memory material where a single interrogation pulse will produce a new pulse pair preserving the relative amplitudes and phases of the preparing pulse pair. Such a coherent superposition state can also be specially tailored along the propagation path to generate Raman scattering in a relatively short distance with very high efficiency.

关键词： coherent superposition preparing

960 MPa Grade High Performance Weldable Structural Steel Plate Processed by Using TMCP

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Journal of Iron and Steel Research International 2010年第2期17卷 63-66页

作者： NIE yi SHANG cheng-jia YOU Yang LI Xiu-cheng CAO Jian-ping HE Xin-lai School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To develop high strength, good toughness, and weldable steel plate, a steel composition was designed. It was an ultra-low-carbon microalloyed steel. TMCP （thermal mechanical control process） and RPC （relaxation precipitation control） were employed to ensure fine lath bainite microstructure. This kind of microstructure could induce higher strength and better toughness.

关键词： low-carbon bainitic steel acicular ferrite substructure relaxation precipitation control

Microstructural evolution of Al-Si coating and its influence on high temperature tribological behavior of ultra-high strength steel against H13 steel

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Journal of Iron and Steel Research International 2017年第10期24卷 1048-1058页

作者： Meng-xuan Guo Kai-xiang Gao wu-rong Wang Xi-cheng Wei School of Materials Science and Engineering Shanghai UniversityShanghai 200072China

Al-Si coated ultra-high strength steel（UHSS）has been commonly applied in hot stamping *** influence of austenitizing temperature on microstructure of Al-Si coating of UHSS during hot stamping process and its tribological behavior against H13 steel under elevated temperature were simulatively *** austenitizing temperature of Al-Si coated UHSS and its microstructual evolution were confirmed and analyzed by differential scanning calorimetry and scanning electron microscopy.A novel approach to tribological testing by replicating hot stamping process temperature history was *** show that the hard and stable phases Fe_2Al_5＋FeAl_2 formed on Al-Si coating surface after exposure to 930°C for 5 min,which was found to be correlated to the tribological behavior of *** friction coefficient of coated steel was more stable and higher than that of uncoated *** main wear mechanism of Al-Si coated UHSS was adhesion wear,while abrasive wear was dominant for the uncoated UHSS.

关键词： Hot stamping Al-Si coating Ultra-high strength steel Intermetallic compound Diffusion Friction coefficient Adhesive wear

基于代谢组学的柠檬烯抗非小细胞肺癌作用机制研究

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中国现代应用药学 2024年第2期41卷 192-202页

作者：张华敏程龙慧董雪漫叶璐徐玉欣陈霖武璞周建良杭州师范大学杭州311121 中南大学长沙410083

目的采用非靶向代谢组学等方法,探究柠檬烯抑制非小细胞肺癌增殖的作用机制。方法以肺癌A549细胞为研究对象,通过CCK-8法测定柠檬烯抑制A549细胞活力及IC_(50);通过集落形成、流式细胞检测、铁含量测定及线粒体染色等实验,分别评价柠... 详细信息

目的采用非靶向代谢组学等方法,探究柠檬烯抑制非小细胞肺癌增殖的作用机制。方法以肺癌A549细胞为研究对象,通过CCK-8法测定柠檬烯抑制A549细胞活力及IC_(50);通过集落形成、流式细胞检测、铁含量测定及线粒体染色等实验,分别评价柠檬烯的体外抗肺癌及诱导铁死亡作用;代谢组学分析发现柠檬烯的潜在作用通路;最后采用Western blotting对相关通路主要蛋白进行验证。结果与对照组相比,柠檬烯给药组可以显著抑制A549细胞的增殖及集落的形成,且呈剂量依赖性;光学显微镜观察发现,柠檬烯给药后A549细胞出现脱落现象,并可显著改变其形态;同时柠檬烯具有诱导A549细胞凋亡作用,并阻滞在G_(0)-G_(1)期;共聚焦显微镜发现柠檬烯作用后,A549细胞线粒体荧光减弱,同时细胞内铁含量亦显著增加,呈现典型的铁死亡表现;代谢组学研究发现谷胱甘肽(glutathione,GSH)代谢、精氨酸生物合成、D-谷氨酰胺和D-谷氨酸代谢及半胱氨酸和蛋氨酸代谢等多条差异代谢通路,这些通路与细胞内GSH合成密切相关;Western blotting实验发现,柠檬烯给药后细胞中SLC40A1、SLC7A11(xCT)及GPX4蛋白含量显著减少。结论柠檬烯抗肺癌作用机制可能与降低肺癌细胞中GSH合成及增加Fe^(2+)含量诱导其铁死亡有关。

关键词：柠檬烯非小细胞肺癌代谢组学铁死亡