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Electric transport properties and temperature stability of magnetoresistance of composite system between La_(8/9)Sr_(1/45)Na_(4/45)MnO_3 and Sb_2O_3

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Rare Metals 2013年第4期32卷 363-368页

作者： Gui-Ying Wang Yong-Gang Tang Qi-Xiang Song Ming-Yu Zhang zhen-sheng peng Anhui Key Laboratory of Spintronic and Nano-materials Research School of Mechanical and Electronic Engineering Suzhou University

The samples ofLa8/9Sr1/45Na4/45MnO3 （LSNMO）/x/2（Sb2O3） were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance （MR） of the samples were studied through the measurements of X-ray diffraction patterns, resistivity-temperature （ρ-T） curves, mass magnetization-temperature （σ-T） curves, and magnetoresistance-temper-ature （MR-T） curves. The results indicate that the p-Tcurves of the original material LSNMO show two peaks, and the phenomenon of two peaks of ρ-T curves disappears for the composite samples, which can be explained by a competition between surface-phase resistivity induced by boundary-dependent scattering and body-phase resistivity induced by paramagnetism-ferromagnetism transition. For all the sam-ples in the low temperature range, MR increases continu-ously with the decrease of temperature, which shows a characteristic of low-field magnetoresistance. However, MR basically keeps the same in the high temperature range. The paramagnetism-ferromagnetism transition is observed in the high temperature range due to a composite between perov-skite manganite and insulator, which can enhance the tem-perature of MR appearance in the high temperature range and make it to appear near room temperature. For the sample with x = 0.12, MR remains constant at the value of 7.5 % in the temperature range of 300-260 K, which achieves a tem-perature stability of MR near room temperature. In addition,for the sample with x = 0.16, MR is above 6.8 % in the high temperature range of 318-252 K （△T = 66 K）. MR almost remains constant in this temperature range, which favors the practical application of MR.

关键词： Electric transport property Temperaturestability of magnetoresistance Two-phase composite Perovskite manganite

Abnormal electric transport property and magnetoresistance stability of La-Sr-K-Mn-O system

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Rare Metals 2013年第3期32卷 258-263页

作者： Yong-Gang Tang Gui-Ying Wang Guo-Qing Yan Qi-Xiang Song Ming-Yu Zhang zhen-sheng peng Cultivating Base of Anhui Key Laboratory of Spintronics and Nano-materials Research School of Mechanical and Electronic Engineering Suzhou University

The perovskite samples La1-x（Sr1-yKy）xMnO3 （y = 0.0, 0.2, 04, 0.6, 0.8） were prepared by the solid-state reaction method with comparatively low sintering tem- perature and with comparatively short sintering time, and the electric transport property and temperature stability of MR of this system were studied. The p-T curves show the abnormal phenomenon that with the increase of K doping amount, resistivity increases, and the insulator-metal transition temperature decreases, which is because the influence of the occupation disorder degree of A-site ions σ2 on the electric transport property of perovskite manga- nites is larger than that of the radius of A-site ions （rA）. In the temperature range below 225 K, MR increases contin- uously with the decrease of temperature, which is the characteristic of low-field magnetoresistance; in the com- paratively wide temperature range near 250 K, the MR- T curves of all the samples are comparatively fiat, and the value of MR almost does not change with temperature, which shows the temperature stability of magnetoresis- tance, and can be explained by the competition between the low-field magnetoresistance induced by spin-dependent tunneling of surface phase and the intrinsic magnetoresis- tance of grain phase. The magnetoresistance value of the sample with y = 0.8 keeps at （7.92 ±0.36） % in the very wide temperature range of 225-275 K, and this is a goodreference for the preparation of this kind of sample with practical application value in the future.

关键词： Keywords Magnetoresistance K doping Disorder degree σ2 Electric transport property

Temperature stability of magnetoresistance (MR) and MR enhancement in La_(1-x)(Sr_(1-y)Ag_y)_x MnO_3 system

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Rare Metals 2013年第1期32卷 81-86页

作者： Yong-Gang Tang Gui-Ying Wang Guo-Qing Yan Qi-Xiang Song Ming-Yu Zhang zhen-sheng peng Cultivating Base of Anhui Key Laboratory of Spintronics and Nano-Materials Research School of Mechanical and Electronic Engineering Suzhou University

Polycrystalline samples of Lal-x（Srl-yAgy）x MnO3 （y = 0.0, 0.2, 0.4, 0.6, 1.0） were prepared by the solid-state reaction method. The temperature stability of magnetoresistance and magnetoresistance enhancement in Lal_x（Srl_yAgy）~MnO3 system with both univalent and bivalent elements doped at A site and with unchanged value of Mn~＋/Mn4＋ ratio were explored through the measurements of X-ray diffraction patterns, magnetiza- tion-temperature （M-T） curves, resistivity-temperature （p-T） curves and magnetoresistance-temperature （MR-T） curves. The results are as follows： there are two peaks in the p-T curves of the samples with Ag doping, one is caused by resistance change during the paramagnetism- ferromagnetism transition, and the other is from boundary- dependent scattering of conduction electrons on the boundaries of grains. The peak value of MR increases with increasing Ag doping content, and it increases from 8.2 % for y ---- 0.2 to 29.6 % for y ---- 1.0 under the magnetic field of B = 0.8 T; MR remains a constant of 12 % in the temperature range of 218-168 K for the sample with y = 1.0, and the temperature stability of MR is in favor of the practical application of MR.

关键词： Ag doping Magnetoresistance enhancement Temperature stability Perovskite manganite

Synthesis of ultralong Si_3N_4 nanowires by a simple thermal evaporation method

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Rare Metals 2013年第2期32卷 186-190页

作者： Wen-Qi Wang Xiao-Ping Zou Nan-Jia Zhou Guang Zhu Gui-Ying Wang zhen-sheng peng Anhui Key Laboratory of Spintronics and Nano-materials (Cultivating Base) Suzhou University Research Center for Sensor Technology Beijing Key Laboratory for SensorBeijing Information Science and Technology University Department of Materials Science and Engineering Northwestern University Structure Research Laboratory University of Science and Technology of China

Largescale vaporsolid synthesis of ultralong silicon nitride （Si3N4） nanowires was achieved by using simple thermal evaporation of mixture powders of active carbon and monoxide silicon. The products were charac terized by Xray diffraction, scanning electron microscopy, energydispersive Xray spectroscopy, and transmission electron microscopy. The results suggest that the silicon nitride nanowires have a smooth surface, with lengths of up to several hundreds of microns and diameters of 100300 nm. A detailed study of both the chemical and structural composition was performed. Such ultralong sil icon nitride nanowires demonstrate potential applications as materials for constructing nanoscale devices and as reinforcement in advanced composites.

关键词： Si3N4 nanowires Ultralong Thermal evaporation

Liver as a new target organ in Alzheimer's disease:insight from cholesterol metabolism and its role in amyloid-beta clearance

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Neural Regeneration Research 2025年第3期20卷 695-714页

作者： Beibei Wu Yuqing Liu Hongli Li Lemei Zhu Lingfeng Zeng zhen Zhang Weijun peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina Yangsheng College of Traditional Chinese Medicine Guizhou University of Traditional Chinese MedicineGuiyangGuizhou ProvinceChina Qinhuangdao Shanhaiguan Pharmaceutical Co. LtdQinhuangdaoHebei ProvinceChina National Clinical Research Center for Mental Disorder The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary *** amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs,targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease *** abnormalities are commonly observed in patients with Alzheimer's *** liver is the primary peripheral organ involved in amyloid-beta metabolism,playing a crucial role in the pathophysiology of Alzheimer's ***,impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's *** this review,we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol ***,we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.

关键词： ABCA1 Alzheimer's disease amyloid-beta apolipoprotein E cholesterol metabolism liver liver X receptor low-density lipoprotein receptor-related protein 1 peripheral clearance tauroursodeoxycholic acid

Apoptotic effect and mechanisms of AHPN on human skin malignant melanoma cell A375

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Journal of Nanjing Medical University 2008年第1期22卷 18-22页

作者： Min Pan zhen-hui peng sheng-xiang Xiao Jian-wen Ren Yan Liu Xiao-li Li zheng-xiao Li Department of Dermatology Second Hospital ofXi＇ an Jiaotong University 157 Xiwu Road Xi＇an 710004. Shaanxi Province China

Objective： To study apoptotic effects of synthetic retinoic acid 6-[3-（1-adamantyl）-4-hydroxyphenyl]-2-naphthalene carboxylic acid（AHPN） on human skin malignant melanoma A375 cells in comparison with the natural ligand all-trans-retinoic acid（ATRA） in vitro and the mechanisms related to the actions of AHPN. Methods：MTT assay was used to determine the anti-proliferative effects of AHPN and ATRA on A375 cells. Flow cytometry was performed to investigate the influence of AHPN and ATRA on cell cycle and cell apoptosis. In addition, transfection and luciferase activity assays were employed to explore the mechanisms of how AHPN executes its proapoptotic function. Results：Firstly, AHPN promoted apoptosis and GI arrest in A375 cells compared with ATRA. Secondly, the activity of NF-K B in A375 cells treated with AHPN increased 2-3 times compared with solvent DMSO treatment. Conclusion：AHPN, in comparison with ATRA, is a more effective alternative for therapy of malignant melanoma. The potentially proapoptotic function of AHPN requires activation of NF-K B.

关键词： 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid(AHPN) ATRA A375 cell line apoptosis NF-K B

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高功率波长可调谐的激光器设计

激光杂志 2017年第4期38卷 45-48页

作者：于长兴卢振生张艳鹏绥化学院黑龙江绥化152000

为了改善光纤激光器的输出功率和可靠性,设计高功率波长可调谐光纤激光器,重点设计了抽运和光学谐振腔的工作模式和设备结构,使抽运设备在990nm波长下工作,为光学谐振腔选择了环形结构。通过对比抽运工作方式对激光波长的影响,使用双向... 详细信息

为了改善光纤激光器的输出功率和可靠性,设计高功率波长可调谐光纤激光器,重点设计了抽运和光学谐振腔的工作模式和设备结构,使抽运设备在990nm波长下工作,为光学谐振腔选择了环形结构。通过对比抽运工作方式对激光波长的影响,使用双向抽运方式提供高激光输出功率。介绍了实现高功率输出的包层抽运技术和光纤相容技术,在光学谐振腔的DMD芯片上构建波长调谐坐标系,以调整激光光束入射角度,实现波长可调谐。经实验分析得知,高功率波长可调谐光纤激光器的输出功率高、可靠性强。

关键词：高功率波长调谐光纤激光器设计实现

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu Hao-Yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang sheng-Jie Xu Ya-Qi Li Zhi-zhen Ren Liang Wang Wei-Chang Hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts

Extramedullary plasmacytoma with the uvula as first affected site:A case report

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World Journal of Clinical Oncology 2025年第1期16卷 53-58页

作者： Jing Yang Hui peng sheng-Ke Tu Min Li Kui Song Department of Hematology The First Affiliated Hospital of Jishou UniversityJishou 416000Hunan ProvinceChina Department of Pharmacy The First Affiliated Hospital of Jishou UniversityJishou 416000Hunan ProvinceChina

BACKGROUND Extramedullary plasmacytoma(EMP)represents one of the rarer forms of plasma cell malignancies,capable of impacting a variety of tissues and organs throughout the *** majority of EMP cases are predominantly found in the head and neck region,especially within the laryngopharynx,as well as in the gastrointestinal *** there have been documented instances of oropharyngeal involvement in EMP cases in the academic literature,it is important to note that EMP specifically affecting the uvula is exceedingly ***,it is noteworthy that over 60% of epithelial carcinomas in the upper respiratory tract and oropharynx tend to metastasize to the cervical lymph nodes,indicating a propensity for regional spread in these types of *** this context,we present a rare case of extramedullary plasmacytoma where the uvula served as the initially affected *** case emphasizes the need for heightened awareness among clinicians regarding such unusual comorbidities,as early recognition and diagnosis can significantly influence patient management and treatment *** addition,a review of the relevant literature is included to further educate and inform healthcare professionals about this rare presentation,ultimately aiming to enhance clinical understanding and improve patient care in similar *** SUMMARY A 51-year-old man was admitted to our hospital because of a slowly enlarging neck mass.A physical examination revealed a palpable left lymph node,and magnetic resonance imaging(MRI)of the oropharynx and the neck showed a soft tissue mass in the oropharynx and enlargement of multiple lymph nodes in the *** soft tissue mass was diagnosed as plasmacytoma by immunohistochemical *** immunoglobulins and bone marrow biopsy showed normal ***,we diagnosed that as EMP of the *** four cycles of adjuvant chemotherapy dominated by bortezomib,MRI reexamination showed a significant reduction of the mass

关键词： Extramedullary plasmacytoma Plasmacytoma Uvula Multiple myeloma Case report