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Chinese Physics B 2017年第7期26卷 377-382页

作者： M A Ali M M Uddin M N i Khan F U Z Chowdhury s M Hoque s i liba Department of Physics Chittagong University of Engineering and Technology (CUET) Materials science Division Atomic Energy Center

A series of Ni0.6-x/2Zn0.4-x/2snxFe2O4(x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.3)(NZsFO) ferrite composities have been synthesized from nano powders using a standard solid state reaction technique. The spinel cubic structure of the investigated samples has been confirmed by x-ray diffraction(XRD). The magnetic properties such as saturation magnetization(Ms),remanent magnetization(Mr), coercive field(Hc), and Bohr magneton(μ) are calculated from the hysteresis loops. The value of Msis found to decrease with increasing sn content in the samples. This change is successfully explained by the variation of A-B interaction strength due to sn substitution in different sites. The compositional stability and quality of the prepared ferrite composites have also been endorsed by the fairly constant initial permeability(μ’) over a wide range of frequency. The decreasing trend of μ’ with increasing sn content has been observed. Curie temperature TChas been found to increase with the increase in sn content. A wide spread frequency utility zone indicates that the NZsFO can be considered as a good candidate for use in broadband pulse transformers and wide band read-write heads for video recording. The composition of x = 0.05 shows unusual results and the possible reason is also mentioned with the established formalism.

关键词： magnetic properties saturation magnetization permeability Curie temperature

study of the Crystallographic and Magnetic structure in the Nickel substituted Cobalt Ferrites by Neutron Diffraction

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Materials sciences and Applications 2015年第4期6卷 332-342页

作者： sadia Khanam A. K. M. Zakaria M. H. Ahsan T. K. Datta s. Aktar s. i. liba s. Hossain A. K. Das i. Kamal s. M. Yunus D. K. saha s.-G. Eriksson Department of Physics Shahjalal University of Science & Technology Sylhet Bangladesh institute of Nuclear science & Technology Bangladesh Atomic Energy Commission Dhaka Bangladesh Atomic Energy Centre Bangladesh Atomic Energy Commission Dhaka Bangladesh Department of Chemical and Biological Engineering Chalmers University of Technology Gothenburg Sweden

The polycrystalline spinel oxides NiX?Co1-X?Fe2O4 with composition x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 were prepared by conventional solid state ceramic sintering technique in air at 1300°C. X-ray diffraction experiments were carried out on all the samples at room temperature in order to characterize the materials. X-ray diffraction patterns showed sharp peaks indicating the formation of single phase cubic spinel structure. The neutron diffraction experiments were performed on all samples at room temperature, with an incident monochromatic neutron beam of wavelength λ = 1.5656 Å. The experimental neutron diffraction data were analyzed using the computer program FullProf in the Reitveld method. Reitveld refinement of the neutron diffraction data reveals that the samples possess cubic symmetry corresponding to the space group F d-3m. Cation distribution between the two sublattices of the spinel structure has been found from the analysis of the neutron diffraction data. Lattice parameters, oxygen position parameters, and overall temperature factors have also been determined from the analysis of neutron diffraction data. The lattice parameter decreases and oxygen position parameter increases with increasing Ni content in the system. sublattices and net magnetic moments have been determined from the refinement of neutron diffraction data. The magnetic structure at room temperature was found to be ferrimagnetic for all the samples.

关键词： Ferrites spinel structure Crystal structure Neutron Diffraction Ferrimagnetic

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常见炎症指标对脓毒症心肌病的预测价值

延边大学医学学报 2024年第1期47卷 39-43页

作者：格力巴崔青松通辽市人民医院内蒙古通辽028000 延边大学附属医院吉林延吉133000

[目的]探讨常见炎症指标对脓毒症心肌病的预测价值,旨在为临床评估脓毒症心肌病提供依据.[方法]选择于2021年1月—2021年12月间在延边大学附属医院诊断为脓毒症的60例患者作为研究对象,以入iCU第3天时的超声心动图左心室射血分数(LVEF)0... 详细信息

[目的]探讨常见炎症指标对脓毒症心肌病的预测价值,旨在为临床评估脓毒症心肌病提供依据.[方法]选择于2021年1月—2021年12月间在延边大学附属医院诊断为脓毒症的60例患者作为研究对象,以入iCU第3天时的超声心动图左心室射血分数(LVEF)siMD)组和非siMD组,比较两组患者入院第1、3、5天时的炎症指标变化情况,并分析其与LVEF(%)的相关性;采用受试者工作特征曲线(ROC曲线)分析各时间点(入院第1、3、5天)常见炎症指标对脓毒症心肌病的预测价值,同时分析各时间点各项指标联合对脓毒症心肌病的预测价值.[结果]本组60例脓毒症患者中22例(36.6%)发生脓毒症心肌病,siMD组入院第1、3、5天时的PCT、CRP水平、第1天时的NEUT(%)及第5天时的WBC水平均明显高于非siMD组,差异均具有统计学意义(PiL-6、LYMPH水平、第3、5天时的NEUT(%)水平及第1、3天时的WBC水平间无明显差异(P>0.05).入院第1、3、5天时的PCT、CRP及入院第5天时的WBC水平与LVEF(%)呈负相关(P<0.05).预测脓毒症心肌病的ROC曲线分析结果显示,入院第1天时的CRP曲线下面积最大,为0.977,敏感性和特异性分别为1.000和0.842,截断值为187.34 mg/L.入院第1天时的PCT联合CRP曲线下面积为0.977,敏感性和特异性分别为0.955和0.895.[结论]PCT联合CRP变化与脓毒症心肌病的发生具有相关性,可用于预测脓毒症心肌病的发生,且与心功能呈负相关.

关键词：脓毒症心肌病生物标志物炎症

基于药效学和药动学研究三种丹参酚酸类成分对华法林抗凝作用的影响及机制

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实用药物与临床 2024年第3期27卷 161-168页

作者：赵月孙佳慧姜爽刘艳嘎力巴李棋魏凡舒杨春娟刘高峰哈尔滨医科大学附属第二医院药学部黑龙江省高校重点实验室黑龙江哈尔滨150086 哈尔滨医科大学药学院黑龙江哈尔滨150076

目的研究丹酚酸B、丹酚酸A和迷迭香酸对华法林抗凝作用的影响及机制,为临床合理用药提供基础研究依据和参考。方法药效学实验:将大鼠随机分为空白对照组、丹酚酸B组、丹酚酸A组、迷迭香酸组、华法林对照组、各丹酚酸成分分别与华法林联... 详细信息

目的研究丹酚酸B、丹酚酸A和迷迭香酸对华法林抗凝作用的影响及机制,为临床合理用药提供基础研究依据和参考。方法药效学实验:将大鼠随机分为空白对照组、丹酚酸B组、丹酚酸A组、迷迭香酸组、华法林对照组、各丹酚酸成分分别与华法林联合给药组,含丹酚酸成分组分别连续腹腔注射各丹酚酸成分14 d,在第8天灌胃给予华法林后,在0、4、8、12、24、36、48、72、96、120、144 h采血,用血凝分析仪测定相关凝血时间参数。药动学实验:将大鼠随机分为华法林对照组、各丹酚酸成分分别与华法林联合给药组,联合给药组连续14 d分别腹腔注射各丹酚酸成分,第8天灌胃给予华法林后在0.5、1、1.5、2、4、8、12、24、36、48、72、96、120、144 h采血;血浆蛋白结合率实验是将大鼠分为华法林对照组、不同剂量(低、中、高)的各丹酚酸成分分别与华法林联合给药组,联合给药组连续8 d分别腹腔注射各丹酚酸成分,第8天灌胃给予华法林后1.5 h采血。采用UPLC-Ms/Ms测定华法林对映体血药浓度,用DAs 2.0软件测定药动学参数。结果药效学研究表明,单独应用丹酚酸B和丹酚酸A并不影响凝血时间,但联合华法林后可延长凝血酶原时间(PT)和国际标准化比值(iNR)(P0.05);迷迭香酸单独或联合华法林,均可延长PT、APTT和iNR值(Ps-华法林的C_(max)、AUC_(0-t)、AUC_(0-∞)分别升高11.11%、22.13%和24.05%(Ps-华法林的药动学参数无显著变化;迷迭香酸联合华法林后,R-华法林的C_(max)、AUC_(0-t)、AUC_(0-∞)分别升高32.38%、67.52%和81.04%(Ps-华法林的C_(max)、AUC_(0-t)、AUC_(0-∞)分别升高29.68%、58.08%和67.26%(Ps-华法林和R-华法林代谢,丹酚酸A可抑制R-华法林代谢。三种丹酚酸成分可通过抑制华法林代谢和竞争血浆蛋白结合,增强华法林抗凝作用。华法林与含有这些成分的中药联合应用时,可能增加出血风险。

关键词：华法林丹酚酸B 丹酚酸A 迷迭香酸抗凝作用

Thermal Behavior and Magnetic Properties of Nd-Fe-B Based Exchange spring Nanocomposites Nd4-xTbxFe83.5Co5Cu0.5Nb1B6(x = 0, 0.2, 0.4, 0.6, 0.8 and 1) Melt-spun Ribbons

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Advances in Materials Physics and Chemistry 2017年第6期7卷 223-241页

作者： Palash Chandra Karmaker Mohammad Obaidur Rahman Nguyen Huy Dan samia islam liba Per Nordblad Dilip Kumar saha sheikh Manjura Hoque Materials science Division Atomic Energy CenterDhakaBangladesh Department of Physics Jahangirnagar UniversityDhakaBangladesh institute of Materials science Vietnam Academy of Science and TechnologyHanoiVietnam solid state Physics Department of Engineering ScienceUppsala UniversityUppsalaSweden

Co-rich Nd-Fe-B nanocomposite ribbons with Tb substituted have been fabricated by single roller melt spinning technique of Nd4-xTbxFe83.5Co5Cu0.5Nb1B6 (x = 0, 0.2, 0.4, 0.6, 0.8 and 1) alloys in an argon (Ar) atmosphere at a circumferential speed of 40 m/s. According to the differential scanning calorimeter (DsC) traces the nanocomposite samples have been annealed at different temperatures like 675°C, 687°C, 700°C, 712°C and 725°C for 10 min. Crystallization behavior was studied by X-ray diffraction in which it was found that the XRD patterns are characterized by broad diffused pattern which demonstrate the amorphous state of materials. The ribbon samples were also characterized by vibration sample magnetometer (VsM) and Mössbauer spectroscopy at as-cast and annealed condition. Co-rich and Tb substitution has significantly enhanced the value of coercivity (Hc) and maximum energy product (BH)max. Highest value of Hc and (BH)max has been obtained as 2.36 kOe and 6.11 MGOe for the sample annealed at 700°C for 10 min with higher concentration of Tb. The M-H hysteresis loops show extremely soft natures which do not possess any area. We have found reduced remanent ratio (Mr/Ms) up to 0.49 at optimal annealing temperature 700°C. However, with the annealing of the samples in the above mentioned temperature, evolution of large coercivity was observed due to the formation of exchange couple hard and soft nanocrystal composites. We have investigated the variation of Curie temperature (Tc) with annealing temperature of the melt spun ribbon samples. Mossbauer spectroscopy was carried out to study the hyperfine parameters such as hyperfine field, hyperfine field distribution for full width half maximum (FWHM) and isomer shift of Fe species of these two phases.

关键词： Coercivity Maximum Energy Product Remanent Ratio Nanocomposite Hard and soft Phases

罗汉果总皂苷对高糖高脂饲料联合链脲佐菌素致2型糖尿病大鼠的作用

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中国畜牧兽医 2020年第12期47卷 4148-4155页

作者：李宝铜夏星钟斯然许立拔原鲜玲丘芬广西中医药大学药学院南宁530021

试验旨在研究罗汉果总皂苷改善高糖高脂饲料联合链脲佐菌素致2型糖尿病大鼠的作用,以高糖高脂饮食联合链脲佐菌素建立2型糖尿病大鼠模型,造模成功大鼠灌胃给予罗汉果总皂苷(100、200、400 mg/kg)或二甲双胍(268 mg/kg),每天1次,连续给药... 详细信息

试验旨在研究罗汉果总皂苷改善高糖高脂饲料联合链脲佐菌素致2型糖尿病大鼠的作用,以高糖高脂饮食联合链脲佐菌素建立2型糖尿病大鼠模型,造模成功大鼠灌胃给予罗汉果总皂苷(100、200、400 mg/kg)或二甲双胍(268 mg/kg),每天1次,连续给药4周后,记录“三多一少”指标(24 h内尿量、饮水量和采食量,体重);检测生化指标,分析空腹血糖值(FBG)、血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、胰岛素(iNs)、过氧化氢酶(CAT)、超氧化物歧化酶(sOD)、丙二醛(MDA)、丙氨酸氨基转移酶(AsT)、天冬氨酸氨基转移酶(ALT)、尿素氮(BUN)和肌酐(Cr)水平,采用苏木素-伊红染色法(HE)观察胰腺的病理学改变。与模型组比较,罗汉果总皂苷各剂量组及二甲双胍组均可显著或极显著降低采食量、饮水量、尿量,血液指标FBG、iNs、MDA、TC、TG、BUN和Cr水平、以及AsT和ALT活性(PsOD活性和HDL-C水平显著或极显著升高(P<0.05;P<0.01);胰腺组织中,胰腺细胞数目明显增多,胰腺病理性损伤明显减轻。罗汉果总皂苷及二甲双胍均具有明显改善糖代谢紊乱的作用,同时可明显减轻胰岛素抵抗,增强机体抗氧化应激的能力和改善肝肾功能。

关键词：罗汉果总皂苷 2型糖尿病高糖高脂饮食胰腺

不同部位桂枝与肉桂对佐剂关节炎大鼠抗凝血作用的影响

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壮瑶药研究 2023年第2期 224-228,390-391页

作者：韦露玲杨凌霄许立拔任佳妮黄玉妹滕建北贺州市检验检测中心贺州542899 广西壮瑶药重点实验室广西南宁530200 贺州市人民医院贺州542800 广西中医药大学南宁530200 壮瑶药协同创新中心广西南宁530200 广西壮族自治区民族药资源与应用工程研究中心广西南宁530200

目的:以不同部位桂枝和肉桂为研究对象,研究其对佐剂关节炎大鼠抗凝血作用,以期发现不同部位桂枝和肉桂药效的异同及为其活血化瘀作用机理提供前期基础。方法:参照《中国药典》(2020年版)对桂枝直径描述,设计按横切面直径选取不同取材... 详细信息

目的:以不同部位桂枝和肉桂为研究对象,研究其对佐剂关节炎大鼠抗凝血作用,以期发现不同部位桂枝和肉桂药效的异同及为其活血化瘀作用机理提供前期基础。方法:参照《中国药典》(2020年版)对桂枝直径描述,设计按横切面直径选取不同取材直径的桂枝(A:0.3 cm以下;B:0.3~1 cm;C:1~4 cm);肉桂药材根据药典规定剥取、加工获得。采用水蒸气蒸馏法提取3组桂枝和肉桂中挥发性成分。除正常组外,其余大鼠注射弗氏完全佐剂(FCA)复制佐剂关节炎(AA)模型。5天后,选取80只造模成功大鼠随机分为8组,包括模型组,雷公藤多苷片组(20 mg/kg),桂枝挥发油A、B、C组(0.1 mL/kg)和肉桂挥发油3个剂量组(0.05,0.1和0.2 mL/kg),另取10只大鼠编入正常组。正常组和模型组给予橄榄油(5 mL/kg),其他组分别给予不同试药,1次/d,连续灌胃给药16 d,采用玻片法和玻璃毛细管法检测凝血时间。结果:不同部位桂枝和肉桂均可延长大鼠玻片法和玻璃毛细管法凝血时间,其中以桂枝B、C挥发油和肉桂挥发油0.1 mL/kg剂量组作用最显著。结论:不同部位桂枝和肉桂对佐剂关节炎大鼠都有抗凝血作用,桂枝B、C组和肉桂高剂量组具有明显的抗凝血作用。

关键词：桂枝肉桂佐剂关节炎抗凝血作用