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Hybrid improper ferroelectricity and phase transition behavior of Li_(2)Nd_(2)Ti_(3)O_(10)ceramics with A-site ordered triple-layer Ruddlesden-Popper structure

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Journal of Materiomics 2024年第1期10卷 145-153页

作者： Bi Hui Zhang Diming Xu Rui Ze Guo Lu liu xiao qiang liu Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310058China Key Laboratory of Multifunctional Materials and Structures Ministry of EducationSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an710049China

Hybrid improper ferroelectricity has been extensively reported through theoretical prediction and experimental investigation in the oxides with Ruddlesden-Popper(R-P)***,the experimentally reported ferroelectric materials based on triple-layer R-P structures are rare,and the weak ferroelectricity impedes its practical *** the present work,the single-phase Li_(2)Nd_(2)Ti_(3)O_(10)ceramics with A-site cation ordered triple-layer R-P structure was obtained by spark plasma sintering technique,and the crystal structure of P2_(1)ab symmetry was revealed by neutron powder diffraction and transmission electron microscope ***,the switchable ferroelectricity in Li_(2)Nd_(2)Ti_(3)O_(10)ceramics has been observed at room temperature,and the saturated polarization-electric field hysteresis loop was obtained with P_(r)=0.4μC/cm^(2)under the electric field of 250 kV/*** phase transition behavior of Li_(2)Nd_(2)Ti_(3)O_(10)oxides was revealed by the temperature-dependence Raman and dielectric spectra combined with the piezoelectric property.

关键词： Hybrid improper ferroelectricity A-site ordered Ruddlesden-Popper structure Phase transition behavior

Electric-field-controlled magnetism due to field-induced transition of Pna2_(1)/R3c in Bi_(1-x)Gd_(x)FeO_(3) ceramics

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Journal of Materiomics 2021年第5期7卷 967-975页

作者： Jing Chen Nan Su xiao Li Zhu xiao qiang liu Jin-Xing Zhang Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityNo.38 Zheda RoadHangzhou310027China Department of Physics Beijing Normal UniversityNo.19 Xinjiekouwai StBeijing100875China

BiFeO_(3) has been recognized as one of the most important room-temperature single-phase multiferroic materials,but it still suffers from several drawbacks especially the weak magnetoelectric *** the present work,the electric-field-controlled magnetism is achieved in Bi_(1-x)Gd_(x)FeO_(3) system,which involves a field-induced transition of Pna2_(1)/R3c at the morphotropic phase boundary region,and the magnetic state is switched between cycloidal state and canted antiferromagnetic *** electric-field-controlled magnetism becomes reversible with the help of annealing,which is confirmed by magnetic hysteresis loops and the quantitative ratio of the involved phases for the as-sintered,as-poled and as-annealed *** with the systems of Bi_(1-x)Nd_(x)FeO_(3) and Bi_(1-x)Sm_(x)FeO_(3),it is easier to tune the symmetry from R3c to Pna21 with lower rare earth-content,and the field-induced transition is more apparent and subsequently leads to more significant electric-field-controlled magnetism in a wider composition range.

关键词： Bi_(1-x)Gd_(x)FeO_(3) Morphotropic phase boundary Magnetic properties Electric-field-controlled magnetism

Expression and mutation of c-kit gene in gastrointestinal stromal tumors

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World Journal of Gastroenterology 2003年第11期9卷 2548-2551页

作者： Fei Feng xiao-Hong liu qiang Xie Wei-qiang liu Cheng-Guang Bai Da-Lie Ma, Department of Pathology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China Department of Pathology Changhai Hospital Second Military Medical University Shanghai 200433 China.

AIM: To investigate the expression and mutation of c-kit gene and its correlation with the clinical pathology and prognosis of gastrointestinal stromal tumors (GISTs).METHODS: A total of 94 cases of GISTs, 10 leiomyomas and 2 schwannomas were studied for the expression of KIT by immunohistochemistry. The c-kit gene mutations in exon 11 of these specimens were detected by PCR-SSCP ***: Of the 94 cases of GISTs, 91 (96.8 %) expressed the KIT protein. Leiomyomas and schwannomas were negative for KIT. The c-kit gene mutations of exon 11 were found in 38 out of the 94 cases of GISTs (40.4 %). The mutations involved point mutations (Va1560-Asp, Ile563-Met),del 557-559 and 579ins12. No mutations were detectable in benign GISTs, leiomyomas or schwannomas. The patients with mutation-positive GISTs showed more frequent recurrences, invasion and metastasis in adjacent tissues than those with mutation-negative ***: KIT is a useful marker for diagnosis of *** of the c-kit gene may play a significant role in the pathogenesis of GISTs and may be associated with poor prognosis in patients with GISTs.

关键词：胃肠道基质癌 c-kit基因基因表达基因转化发病机制

A novel sol–gel route to synthesize(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ceramics with enhanced electrocaloric effect

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Journal of Advanced Dielectrics 2017年第2期7卷 28-35页

作者： Ting Chen Shu Ya Wu xiao qiang liu Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and Engineering Zhejiang University Hangzhou 310027 P.R.China

(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ultra-fine powders were synthesized by a novel sol–gel route,and the mechanism of the reaction was ***_(3),BaCO_(3),oxalate niobium and citric acid were used to initiate the sol–gel process,and ethylene glycol(EG)was added to further polymerize the cross-linking *** evolution of the(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) phase,the reaction process and the microstructures were investigated by X-ray diffraction(XRD),Raman spectroscopy,Fourier transform infrared spectroscopy,DSC-TG and scanning electron *** synthesis temperature of the(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) powders reached as low as 1200℃,and the size and morphology of the powders were controlled by *** adjusting the calcination temperature,we obtained(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) powders with uniform sizes of 20 nm to 500 ***,dense(Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ceramics were successfully prepared using these ultrafine ***,an enhanced electrocaloric effect(ECE)value of 0.35℃ was obtained at 100 kV/cm.

关键词： Sol–gel process (Sr_(0.5)Ba_(0.5))Nb_(2)O_(6) ultrafine powders electrocaloric effect

Sand control mechanism of radial well filled with phase change material in hydrate reservoir

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Petroleum Science 2024年第4期21卷 2571-2582页

作者： xiao-qiang liu Zhong-Xi Han Zhi-Lin Luo Hai-Long Lu Ying Sun Qing You Tian-Kui Guo Zhan-Qing Qu School of Energy Resources China University of Geosciences(Beijing)Beijing10083China Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering China University of Geosciences(Beijing)Beijing10083China China Research Institute of Petroleum Exploration and Development Beijing10083China Engineering Technology Research Institute of Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China School of Advanced Material Peking University Shenzhen Graduate SchoolShenzhen518055GuangdongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580shandongChina

Radial well filled with phase change material has been proposed as a novel sand control method for hydrate *** order to reveal the sand control mechanism,CFD-DEM coupling method is applied to simulate the migration,settlement,and blockage processes of sand particles in the radial *** obtained results indicate that three scenarios have been recognized for sand particles passing through sand control medium,based on the diameter ratio of sand control medium to sand particle(D_(d)):fully passing(D_(d)=8.75-22.5),partially passing and partially blocked(D_(d)=3.18-5.63),and completely blocked(D_(d)=2.18-3.21).After being captured by the sand control medium,sand particles can block pores,which increases fluid flow resistance and causes a certain pressure difference in the radial *** pressure in the radial well should be lower than the hydrate phase equilibrium pressure during sand control design,for the purpose of promoting hydrate decomposition,and sand *** length of the radial well should be optimized based on the reservoir pore pressure,production pressure difference,bottom hole pressure,and the pressure gradient in the radial *** should be noticed that the sand control medium leads to a decrease in permeability after sand particles *** the permeability is reduced to several hundred millidarcy,it is still sufficient to ensure the effective flow of gas and water after hydrate *** fluid velocity reduces the blocking capacity of the sand control medium,mainly because of deterioration in bridging between sand particles.

关键词： Hydrate reservoir Sand control Radial well CFD-DEM

Development of self-generated proppant based on modified low-density and low-viscosity epoxy resin and its evaluation

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Petroleum Science 2022年第5期19卷 2240-2252页

作者： Jia-Cheng Fan Zhan-Qing Qu Tian-Kui Guo Ning Qi Ming Chen Jian Hou Ji-Jiang Ge xiao-qiang liu Ji-Wei Wang College of Petroleum Engineering China University of PetroleumQingdao266580ShandongChina Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

Hydraulic fracturing is a critical technology for the economic development of unconventional oil and gas *** main factor influencing fracture propping and reservoir stimulation effect is proppant *** increasing depth of fractured oil and gas reservoirs is causing growing difficulty in hydraulic ***,the migration of conventional proppants within the fracture is always limited due to small fracture width and rigid proppant ***,proppants with good transportation capacity and fracture propping effects are ***,a novel self-generated proppant based on toughened low-viscosity and low-density epoxy resin was developed to satisfy this ***,proppant performances were ***-viscosity and low-density epoxy resin was generated when the thiol-ene click chemical reaction product of eugenol and 1-thioglycerol reacts with the ***,the resin was toughened with graphite particles to increase its compressive strength from50.8 to 72.1 MPa based on micro-cracking mechanism and crazing-nail anchor *** adduct of diethylene triamine and butyl glycidyl ether and the Si O2 nanoparticles were treated as the curing agent and emulsifier respectively to form the *** emulsion is transformed into solid particles of various sizes within a reservoir to prop the *** shows good migration capacity of this self-generated proppant due to the low density of epoxy resin.

关键词： Low-viscosity and low-density epoxy resin Resin toughening Self-generated proppant Performance evaluation

Restoration of outer segments of foveal photoreceptors after resolution of malignant hypertensive retinopathy

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International Journal of Ophthalmology(English edition) 2012年第6期5卷 776-778页

作者： xiao-qiang liu Xin-Rui Gao Ding Xu Chong Xu Li-Ning Cao Fang Wang Department of Ophthalmology Shanghai Tenth People's Hospital Tongji University School of Medicine

Dear Sir,I am Dr. xiao-qiang liu, from the Department of Ophthalmology, Shanghai Tenth People’s Hospital,Tongji University School of Medicine, Shanghai, China. I write to report a case of malignant hypertensive retin... 详细信息

关键词： line Restoration of outer segments of foveal photoreceptors after resolution of malignant hypertensive retinopathy OS

Seminal plasma miR-210-3p induces spermatogenic cell apoptosis by activating caspase-3 in patients with varicocele

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Asian Journal of Andrology 2020年第5期22卷 513-518页

作者： Ya-Wei Xu Ning-Jing Ou Yu-Xuan Song Xian-Hao Wang Jia-Qi Kang Yong-Jiao Yang Ye-Gang Chen xiao-qiang liu Departm ent of Urology Tianjin Medical University General HospitalTianjin 300052China Department of Urology Tianjin Institute of UrologyThe Second Hospital of Tianjin Medical UniversityTianjin 3CX3211China

The aim of this study was to investigate the role of seminal plasma miR-210-3p in the impairment of semen quality caused by *** study included 102 patients whose semen quality was normal when they were diagnosed with varicocele.A 2-year follow-up for included patients was performed,and they were divided into Group A(semen quality became abnormal)and Group B(semen quality remained normal)according to the results of semen analysis during the *** parameters and seminal plasma miR-210-3p expression were investigated by semen analysis and quantitative real-time polymerase chain reaction,*** vitro experiments with GC-2 cells were performed to explore the role of miR-210-3p in spermatogenic *** results of quantitative real-time polymerase chain reaction showed that the level of seminal plasma miR-210-3p in Group A was higher than that in Group B both after 2-year follow-up and when they were diagnosed with varicocele(both P<0.01).Apoptosis and proliferation assays showed that miR-210-3p induces apoptosis of spermatogenic cells by promoting caspase-3 *** conclusion,our study indicated that seminal plasma miR-210-3p induces spermatogenic cell apoptosis by activating caspase-3 in patients with *** plasma miR-210-3p may be a potential biomarker for predicting impaired semen quality caused by varicocele.

关键词： biomarker cleaved caspase-3 m iR-210-3p semen quality varicocele

安哥拉Gandjelas混凝土重力坝安全检测与评价分析(英文)

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岩土工程学报 2008年第11期30卷 1683-1691页

作者： KE Min-yong YE xiao-qiang liu Hai-xiang JIN Chu-yang Nanjing Hydraulic Research Institute Nanjing 210029 China

介绍了安哥拉Gandjelas重力坝的现场调查、检测、试验和理论分析的方法、依据和主要结论。检测表明,原混凝土的水平施工缝张开,层间施工质量难以保证;复核计算表明大坝整体稳定略显不足,坝体应力分布符合DL5108—1999《混凝土重力坝设... 详细信息

介绍了安哥拉Gandjelas重力坝的现场调查、检测、试验和理论分析的方法、依据和主要结论。检测表明,原混凝土的水平施工缝张开,层间施工质量难以保证;复核计算表明大坝整体稳定略显不足,坝体应力分布符合DL5108—1999《混凝土重力坝设计规范》规定。为综合解决整体稳定不足、渗漏和外观缺陷等影响正常运行的问题,建议在大坝上游面采用预应力岩锚加固,上游面裂缝采用灌浆、嵌缝和使用水泥结晶防渗材料处理等综合措施,下游溢流面采用20mm丙乳砂浆修补,廊道内裂缝进行EA改性环氧灌浆材料灌浆处理。

关键词：病害检测安全评估混凝土重力坝