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Distinct microstructure and property evolution of 0.76(Bi_(0.5)Na_(0.5))TiO_(3)-0.24SrTiO_(3) ferroelectric ceramics synthesized with different TiO_(2) reactants

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Journal of Materials Science & Technology 2023年第20期151卷 73-79页

作者： Jian guo Ji Zhang Jing Wang shan-Tao Zhang National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences&Jiangsu Key Laboratory of Artificial Functional Materials&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China School of Materials Science and Engineering Nanjing University of Science&TechnologyNanjing 210094China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Single phase 0.76(Bi_(0.5)Na_(0.5))TiO_(3)–0.24SrTiO_(3) ferroelectric ceramics have been synthesized with homogenous anatase and hierarchical rutile TiO_(2) raw reactants(BNST-A and BNST-R).Either calcined powder persists the microstructure characteristics of raw *** the result,when the sintering temperature increases from 1000 to 1200℃,the average grain size and density of BNST-A increase from 0.49 to 1.48μm and 5.02 to 5.61 g/cm^(3),while those of BNST-R from 0.86 to 1.44μm and 5.37 to 5.61 g/cm^(3).BNST-A illustrates a predominant ergodic relaxor state,and BNST-R prefers a non-ergodic relaxor state,as evidenced by the distinct polarization-electric field loops and current-electric field ***,such a distinct ferroelectric state is independent of sintering *** is believed that the special hierarchical microstructure of rutile TiO_(2) reactant is beneficial to form denser ceramics with larger grains,and thus suppresses the contributions of polar nanoregions and defect-induced built-in field to ferroelectric property,leading to non-ergodic relaxor *** work clearly demonstrates the nonnegligible effects of TiO_(2) reactants on the microstructure and properties of BNST ferroelectric ceramics.

关键词： BNST ferroelectric ceramics TiO_(2)raw reactants Microstructure and property evolution

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Influence of carbon content on microstructure and mechanical properties of 1000 MPa deposited metal by gas metal arc welding

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Journal of Iron and Steel Research International 2019年第5期26卷 512-518页

作者： Tong-bang An Jin-shan Wei Lin Zhao Ji-guo shan Zhi-ling Tian Central Iron & Steel Research Institute Beijing 100081 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

The effects of carbon content (0.078-0.100 wt.%) on the microstructure and properties of 1000 MPa grade deposited metal produced by gas metal arc welding have been investigated. Experimental results show that the microstructure of the deposited metal was mainly composed of martensite, bainite and retained austenite. With increasing carbon content, the proportion of martensite increased, and the amount of bainite was reduced. High carbon content is beneficial to strength, but harmful to impact toughness, and thus, carbon reductions lead to the increase in impact toughness. When the carbon content was 0.100 wt.%, the lowest Charpy absorbed energy of 47 J at — 40℃ for the deposited metal was achieved, the highest yield strength of 1038 MPa was attained, and the yield-to-tensile ratio was more than 0.88, while the highest Charpy absorbed energy of 55.7 J at — 40℃ and the lowest yield strength of 915 MPa were obtained when the deposited metal contains 0.078 wt.% C, and the yield-to-tensile ratio was less than 0.85. It is concluded that bainite fraction and fine effective grain size were the dominant factors to achieve good comprehensive mechanical properties (the required strength and an acceptable toughness) of deposited metals with various carbon contents.

关键词： 1000 MPa grade deposited metal Carbon content Microstructure Strength Gas metal arc welding Impact toughness

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A General Law of Precise Asymptotics for Products of Sums under Dependence

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Acta Mathematica Sinica,English Series 2010年第1期26卷 107-116页

作者： Yong ZHANG Xiao yun YANG Zhi shan DONG College of Mathematics Jilin University Changchun 130012 P. R. China

Let {Xn,n ≥ 1} be a strictly stationary LNQD （LPQD） sequence of positive random variables with EX1 = μ 〉 0, and VarX1 = σ^2 〈 ∞. Denote by Sn = ∑i=1^n Xi and γ = σ/μ the coefficients of variation. In this paper, under some suitable conditions, we show that a general law of precise asymptotics for products of sums holds. It can describe the relations among the boundary function, weighted function, convergence rate and limit value in the study of complete convergence.

关键词： general law precise asymptotics products of sums NA (PA) LNQD (LPQD)

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Cerebral venous sinus thrombosis in pregnancy: A case report

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World Journal of Clinical Cases 2022年第1期10卷 309-315页

作者： Biao Zhou shan-shan Huang Can Huang Shu-yun Liu Department of Neurology Dongguan Tungwah HospitalDongguan 523000Guangdong ProvinceChina Department of Intensive Care Unit The Seventh Affiliated HospitalSun Yat-Sen UniversityShenzhen 518000Guangdong ProvinceChina Department of Neurology Shenzhen Longhua District Central HospitalShenzhen 518000Guangdong ProvinceChina

BACKGROUND Cerebral venous thrombosis(CVT)is a rare but life-threatening disease in pregnant *** is the first-line therapy for CVT ***,some patients have poor outcomes despite ***,the endovascular treatment of CVT in pregnant women remains *** report a rare case of CVT in a pregnant woman who was successfully treated with two stent retriever *** SUMMARY The patient was a 29-year-old pregnant *** was first diagnosed with hyperemesis gravidarum due to severe nausea and vomiting for one *** the disease progressed,she developed acute left *** confirmed the diagnosis of superior sagittal sinus,right transverse sinus and sinus sigmoideus *** anticoagulant therapy was ineffective,she underwent *** the mechanical thrombectomy,her headache *** weeks later,the patient was completely *** a 3-mo follow-up,no relapse of symptoms was *** Mechanical thrombectomy may be an effective alternative therapy for CVT in pregnant women if anticoagulation therapy fails.

关键词： Pregnancy Cerebral venous thrombosis Anticoagulation Mechanical thrombectomy Case report

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A New Sufficient Degree Condition for a Graphic Sequence to Be Forcibly k-Edge-Connected

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 223-228页

作者： Jian-hua YIN Ji-yun guo School of Science Hainan UniversityHaikou 570228China

A graphic sequence π =(d1, d2,..., dn) is said to be forcibly k-edge-connected if every realization of π is k-edge-connected. In this paper, we obtain a new sufficient degree condition for π to be forcibly k-edgeconnected. We also show that this new sufficient degree condition implies a strongest monotone degree condition for π to be forcibly 2-edge-connected and a conjecture about a strongest monotone degree condition for π to be forcibly 3-edge-connected due to Bauer et al.(Networks, 54(2)(2009) 95-98), and also implies a strongest monotone degree condition for π to be forcibly 4-edge-connected.

关键词： graphic sequence forcibly k-edge-connected graphic sequence a strongest monotone degree condition

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Finite NPDM-groups

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Acta Mathematica Sinica,English Series 2021年第2期37卷 306-314页

作者： Jian Ji CAO Xiu yun guo School of Applied Mathematics Shanxi University of Finance and EconomicsTaiyuan 030006P.R.China Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

In this paper the classification is given for finite groups in which the normalizer of every non-normal cyclic subgroup of order divided by the minimal prime of |G| is a maximal subgroup.

关键词： Normalizer cyclic subgroup maximal subgroup

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Maternal and fetal death associated with acute pancreatitis during pregnancy:A case report

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World Journal of Clinical Cases 2025年第10期13卷 53-58页

作者： Jin Li Qing-Yan Zhang Mei-Hong Zhang shan-yun Jiang Department of Anesthesiology Kaihua County People’s HospitalQuzhou 324300Zhejiang ProvinceChina Center for Clinical Inspection and Quarantine Kaihua County Center for Clinical Inspection and QuarantineQuzhou 324300Zhejiang ProvinceChina

BACKGROUND Acute pancreatitis in pregnancy is a rare but serious condition that can lead to high maternal mortality and fetal *** of pregnancy complicated by severe acute pancreatitis,particularly with subsequent respiratory and cardiac arrest,are rarely *** SUMMARY We present the case of a 35-year-old woman,at 36+5 weeks of gestation,who presented with paroxysmal epigastric pain accompanied by low back pain,nausea,and *** to the clinical symptoms,B-ultrasound imaging and biochemical indicators,the patient was diagnosed with acute pancreatitis and initially managed ***,3 hours after admission,the patient experienced respiratory and cardiac arrest,and the fetus *** this case,the adverse outcomes occurred due to the lack of aggressive fluid resuscitation and an active surgical *** Implementing aggressive fluid resuscitation to sustain tissue perfusion,alongside the proactive evaluation of pharmacological agents that suppress gastric acid secretion and inhibit pancreatic enzyme activity,may be beneficial in mitigating the risk of a severely adverse *** management of acute pancreatitis during pregnancy requires careful timing of surgical intervention,a thorough evaluation of the risks and benefits regarding the continuation or termination of pregnancy,and a focus on safeguarding both maternal and fetal health.

关键词： Severe acute pancreatitis Pregnancy Cardiac arrest Fetal death Case report

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Synthesis of Calix[4]resorcinarene Core Dendrimers with Peripheral Salicylideneimine Functional Groups

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Chemical Research in Chinese Universities 2006年第4期22卷 537-542页

作者： HAN Jun GE yun YAN Chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

First to third-generation calix[4] resorcinarene core dendrimers, compounds 4a, 4b, 7a, 7b, 10a and 10b, were prepared via the divergent method in seven steps with the corresponding tetraphenyl- and tetra （hydroxyphenyl） calix[4] resorcinarenes （compounds 1a, 1b） as the starting material. The repeat units of the polyamidoamines of these dendrimers were obtained by the ammonolysis of ethyl calixarylacetates 2a and 2b with 1,3-diaminopropane, that is, amide derivatives with terminal amino groups, which in turn reacted with ethyl acrylate to give a higher generation of ester derivatives. The structures of these dendrimers were characterized by IR, ^1H and ^13C NMR spoctrometries. The crystal structure of compound 2b with 12 ethoxycarbonylmethoxy groups was determined by X-ray analysis.

关键词： Calixresorcinarene Dendrimer Schiffbase Amide Calixarene

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Endoscopic ultrasonographic features of gastric linitis plastica in fifty-five Chinese patients

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第9期14卷 844-848页

作者： guo-dong shan guo-qiang XU You-ming LI Department of Gastroenterology the First Affiliated HospitalSchool of MedicineZhejiang University

The objective of this study was to investigate the endosonographic appearance of gastric linitis plastica(GLP) and to study the usefulness of endoscopic ultrasonography(EUS) for the T and N staging of *** examinations of 55 patients with histologically proven GLP were retrospectively *** all patients,EUS showed that lesions involved at least one-third of the circumference of the *** on the findings of the EUS,the 55 patients were divided into two *** were 32(58.2%) patients in the first *** of this group showed that the five sonographic layers had disappeared and had been replaced by a hypoechogenic thickening of the gastric *** were 23(41.8%) patients in the second *** of this group showed that the first three sonographic layers were blurred and thickened,and the fourth layer was significantly *** full thickness of the gastric wall was significantly thicker in first than in the second group of patients(P<0.01).The incidence of perigastric lesions was significantly higher in the first than in the second group of patients(P<0.01).Results for the 15 patients following preoperative EUS were compared postoperatively with histopathologic findings for T and N *** overall diagnostic accuracy of the T stage was 73.3% and of the N stage was 60.0%.In eight patients,we used EUS to assess a therapeutic *** response was observed in five patients and a partial response in *** images of GLP are *** is helpful in diagnosing GLP and for assessing the T and N stages.

关键词： Gastric linitis plastica Endoscopic ultrasonography Diagnosis Differentiation Follow-up

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Biofluid Biomarkers of Alzheimer's Disease:Progress,Problems,and Perspectives

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Neuroscience Bulletin 2022年第6期38卷 677-691页

作者： shan Huang Yan-Jiang Wang Junhong guo Department of Neurology First HospitalShanxi Medical UniversityTaiyuan 030000China Department of Neurology and Centre for Clinical Neuroscience Daping HospitalThird Military Medical UniversityChongqing 400042China

Since the establishment of the biomarker-based A-T-N(Amyloid/Tau/Neurodegeneration)framework in Alzheimer's disease(AD),the diagnosis of AD has become more precise,and cerebrospinal fluid tests and positron emission tomography examinations based on this framework have become widely ***,the A-T-N framework does not encompass the whole spectrum of AD pathologies,and problems with invasiveness and high cost limit the application of the above diagnostic methods aimed at the central nervous ***,we suggest the addition of an“X”to the A-T-N framework and a focus on peripheral biomarkers in the diagnosis of *** this review,we retrospectively describe the recent progress in biomarkers based on the A-T-N-X framework,analyze the problems,and present our perspectives on the diagnosis of AD.

关键词： Alzheimer's disease Biomarker Amyloidbeta Tau Diagnosis

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