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Blowing up of Solutions to the Cauchy Problem for the Generalized Zakharov System with Combined Power-Type Nonlinearities

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Acta Mathematica Sinica,English Series 2012年第9期28卷 1917-1936页

作者： Zai Hui GAN Bo Ling GUO chun xiao GUO College of Mathematics and Software Science Sichuan Normal University Institute of Applied Physics and Computational Mathematics Department of Mathematics China University of Mining and Technology Beijing

This paper deals with blowing up of solutions to the Cauchy problem for a class of general- ized Zakharov system with combined power-type nonlinearities in two and three space dimensions. On the one hand, for co = ＋oo we obtain two finite time blow-up results of solutions to the aforementioned 4 ≤ p 〈 N＋2/N-2 4 system. One is obtained under the condition a ≥ 0 and 1 ＋ 4/N or a 〈 0 and 1 〈 p 〈 1 ＋（N = 2,3）; the other is established under the condition N = 3, 1 〈 p 〈 N=2/N-2 and α（p - 3）〉 0. On the other hand, for co 〈＋∞ and α（p - 3）〉 0, we prove a blow-up result for solutions with negative energy to the Zakharov system under study.

关键词： Generalized Zakharov system blowing up combined power-type nonlinearities Lyapunov function in time

Effect of microstructure on the impact toughness of a bainitic steel bloom for large plastic molds

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 842-850页

作者： Zheng Zhang xiao-chun Wu Quan Zhou Li-li Duan School of Materials Science and Engineering Shanghai University

The correlation between the impact toughness and microstructural characteristics of a large bainitic steel bloom has been investigated. The study focuses on microcrack nucleation and propagation in the basic cleavage plane. To analyze the phase transformation during the wind-cooling process, the temperature field of the bloom was acquired by computer simulation, and a continuous cooling transformation experiment was conducted. The results show that compared with the surface of the bloom, the toughness of the bloom’s core is decreased by the increase in proeutectoid ferrite and the coarsening of tempered martensite–austenite constituents. The proeutectoid ferrite decreases the toughness via its effects on carbide precipitation, the formation of martensite–austenite constituents, and the bainite transformation. The relatively large tempered martensite–austenite constituents are conducive to microcrack nucleation and propagation.

关键词： mold steel microstructure impact toughness cooling

Optical quasi-periodic oscillation and color behavior of blazar PKS 2155–304

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Research in Astronomy and Astrophysics 2014年第8期14卷 933-941页

作者： Bing-Kai Zhang xiao-Yun Zhao chun-xiao Wang Ben-Zhong Dai Department of Physics Fuyang Normal College Department of Physics Yunnan University

PKS 2155-304 is a well studied BL Lac object in the southern sky. The historical optical data during different periods have been collected and compiled. Light curves spanning 35 yr have been constructed. The R-band light curve has been ana- lyzed by means of three methods： the epoch folding method, the Jurkevich method and the discrete correlation function method. It is derived that there is an evident periodic component of 317 d （i.e. 0.87 yr） superposed on a long-term trend with large- amplitude variation in the light curve. The variability of this source is accompanied by a slight color variation, and the brightness and color index are correlated with each other. On a long-term time scale, PKS 2155-304 exhibits a tendency of bluer-when- brighter, which means the spectrum becomes flatter when the source brightens.

关键词： BL Lacertae objects general -- BL Lacertae objects individual (PKS 2155-304) -- galaxies active -- method statistical

Rapid removal of copper impurity from bismuth-copper alloy melts via super-gravity separation

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International Journal of Minerals,Metallurgy and Materials 2021年第12期28卷 1929-1939页

作者： xiao-chun Wen Lei Guo Qi-peng Bao Zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

A green method of super-gravity separation,which can enhance the filtration process of bismuth and copper phases,was investigated and discussed for the rapid removal of copper impurity from bismuth-copper alloy *** separation by the super-gravity field,the bismuth-rich liquid phases were mainly filtered from the alloy melt along the super-gravity direction,whereas most of the fine copper phases were retained in the opposite *** optimized conditions of separation temperature at 280℃,gravity coefficient at 450,and separation time at 200 s,the mass proportion of the separated bismuth from the Bi-2 wt%Cu and Bi-10 wt%Cu alloys respectively reached 96%and 85%,which indicated the minimal loss of bismuth in the ***,the removal ratio of impurity copper from the Bi-2 wt%Cu and Bi-10 wt%Cu alloys reached 88%and 98%,***,the separation process could be completed rapidly and is environmentally friendly and efficient.

关键词： alloy alloys separation

Twin pregnancy with sudden heart failure and pulmonary hypertension after atrial septal defect repair: A case report

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World Journal of Clinical Cases 2023年第35期11卷 8350-8356页

作者： chun-xiao Tong Tao Meng Department of Obstetrical First Affiliated Hospital of China Medical UniversityShenyang 110000Liaoning ProvinceChina

BACKGROUND Pulmonary arterial hypertension(PAH)in pregnancy is one of the major obstetric complications and is considered a contraindication to pregnancy as it is classified as a class IV risk in the revised risk classification of pregnancy by the World Health ***,with its adaptive and expectant mechanical and hormonal changes,negatively affects the cardiopulmonary circulation in pregnant *** patients with repaired simple congenital heart disease(CHD)develop other pulmonary and cardiac complications during pregnancy?Can pregnant women with sudden pulmonary hypertension be treated and managed in time?In this paper,we present a case of a 39-year-old woman who underwent cesarean section at 33 wk'gestation and developed PAH secondary to repaired simple *** research began by a PubMed search for"pulmonary hypertension"and"pregnancy"and"CHD"case *** cases were selected to review PAH in pregnancy after correction of CHD *** studies were reviewed,coupled with our own clinical *** SUMMARY Herein,a case involving a woman who underwent atrial septal defect repair at the age of 34,became pregnant five years later,and had a sudden onset of PAH and right heart failure secondary to symptoms of acute peripheral edema in the third trimester of her *** a result,the patient underwent a cesarean section and gave birth to healthy *** three days after cesarean delivery,her cardiac function deteriorated as the pulmonary artery pressure ***-tive postpartum management,including diuresis,significant oxygen uptake,vasodilators,capacity and anticoagulants management,led to improvements in cardiac function and *** patient was discharged from hospital with a stable recovery and transferred to local hospitals for further PAH *** This case served as a reminder to obstetricians of the importance of pregnancy after repair of *** is crucial for patients with CHD to receive early co

关键词： Congenital heart defects Pulmonary hypertension Right heart failure Twin pregnancy Perioperative management Case report

Lost expression of thyroid hormone receptor-β1 mRNA in esophageal cancer

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Frontiers in Biology 2012年第4期7卷 368-373页

作者： Hao LI xiao-chun XU Department of Clinical Cancer Prevention UTM. D. Anderson Cancer Center Houston TX 77030 USA Department of Pathology Anhui Medical University Hefei 230032 China

Thyroid hormone receptors （TR）, ligand-mediated transcription factors, regulate cell growth, differentiation, and apoptosis. In humans, two different genes encode TR-α and TR-β and they are often co-expressed in various tissues at different levels. To explore the role of TR in esophageal cancer, we analyzed expression of TR-β1 mRNA （most abundantly expressed in the majority of normal cells） in normal and malignant esophageal tissue specimens using in situ hybridization. The TR-β1 mRNA was detected in 92.3% （96 of 104） of normal esophageal mucosa, whereas TR-β1 mRNA was only detected in 55.8% （58 of 104 cases） of esophageal squamous cell carcinoma specimens （P〈 0.00001）. Expression of TR-β1 mRNA was associated with well-differentiated cancers （P〈 0.001）. Furthermore, we determined whether the loss of heterozygosity （LOH） in TR-β1 gene locus would be responsible for the lost TR-β1 expression. Analysis of 73 esophageal tissue specimens generated 39 informative cases, 17 of which showed LOH （43.6%） but only 9 of these 17 cases were correlated with lost TR-β1 expression. This study demonstrated that expression of TR-β1 mRNA was lost in esophageal cancer tissues, which may be due to multiple mechanisms.

关键词： esophageal cancer thyroid hormone receptor in situ hybridization LOH

Mechanical properties and charge signal characteristics in coal material failure under different loading paths

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International Journal of Coal Science & Technology 2019年第1期6卷 138-149页

作者： Xin Ding xiao-chun xiao Di Wu Xiang-feng Lv School of Mechanics and Engineering Liaoning Technical University Fuxin 123000China Center of Rock Mechanics and Geological Disasters Shaoxing UniversityShaoxing 312009ZhejiangChina School of Civil and Resource Engineering University of Science & Technology Beijing Beijing 100083 China

Rock burst is a catastrophic dynamic disaster caused by sudden failure and instability of coal, loading paths play an important role in the failure of coal, the coal failure process is associated with charge exception infonnation. Hence, violent coal failure mechanics and time-frequency domain distribution of charge signal such as rock burst under different loading paths should be studied in-depth. In this paper, grade and cyclic loading test were carried out for coal with impact tendency samples produced by blocks cored from 800 depth in xiaoqing coal mine of the Tiefa coal group in northeast China. Theory discussion was carried out for the result of stress and strain, frequency-spectra analysis was conducted for the wavelet charge data, figures showing the evolution mechanism of mechanical properties and the relationship of timefrequency domain amplitude of charge signals in coal with different loading paths and stage were obtained. The failure process and characteristics of coal under different loading paths were summarized. It found that the loading path changed the manner of energy accelerate-release, there were more plastic strain generation in coal under cyclic loading than that under grade loading, the former was more likely to cause greater damage and failure, then the strength of coal under cyclic loading is generally lower than that under grade loading, an energy conversion mechanical model of stress, damage and deformation was developed and explained the effect of the loading path. Charge signal was primarily distributed in the strengthening and peak stages, where there was a high amplitude pulse at each stress drop. The charge pulse was a type of low frequency signal with a primary frequency distribution range of 1 -100Hz. Discussion on the charge generating mechanism from the perspective of friction slip, it demonstrated that the charge obtained during the coal failure process directly to stress loaded on and damage, the result verified it better. We p

关键词： Rock burst Coal failure Loading path Damage Energy accelerate-release Charge time-frequency signal

Research on the Mechanism and Prevention of Rockburst at the Yinxin Gold Mine

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Journal of China University of Mining and Technology 2007年第4期17卷 541-545页

作者： ZHANG xiao-chun WANG Jun-qiang Traffic and Communications College Southeast University Nanjing Jiangsu 210096 China Lingbao Gold Company Ltd Lingbao Henan 472500 China

The occurrence and nature of shaft rockburst in the Yinxin gold mine are recorded and analyzed. Rockburst happens along an obvious south-north orientation. The ground and surrounding rock stresses are measured in this mine. The research indicates that the directivity of rockburst is closely related to geological structure and to abnormal distri-bution of ground stress in some parts of the mining area. The mechanism of past rockbursts is discussed based upon the theory of fracture mechanics. Some rockburst release measures and their execution in the Yinxin Gold Mine are de-scribed. These measures have been successful in eliminating rockburst.

关键词： rockburst geological tectonic stress crack extension shaft release technology

Primary shunt hyperbilirubinaemia in a large four-generation family confirming autosomai dominant genetic disorder

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World Journal of Gastroenterology 2006年第19期12卷 3123-3125页

作者： chun-Lian Wang xiao-Wei Liu Fang-Gen Lu xiao-Ping Wu chun-Hui Ouyang Dong-Ye Yang Department of Gastroenterology the Second Xiangya Hospital Central South University Changsha 410011 Hunan Province China

AIM： To describe the pattern of inheritance and confirm the diagnostic criteda of primary shunt hyperbilirubinaemia （PSH）. METHODS： Forty members of a family pedigree across four generations were included in this study. All family members were interviewed and investigated by physical examination, hematology and liver function test and the pattern of inheritance was analyzed. RESULTS： Nine of the forty family members suffered primary shunt hyperbilirubinaemia. The mature erythrocytes of the propositus were irregular in shape and size. The pedigree showed transmission of the trait through four generations with equal distribution in male and female. No individual with a primary shunt hyperbilirubinaemia was born to unaffected parents. The penetrance was complete in adult. CONCLUSION： The pattern of inheritance is autosomal dominant. The abnormality of erythrocytes and decrease in white blood cell could be supplemented in the diagnosis of PSH. The PSH is a genetic disorder and could by renamed as hereditary shunt hyperbilirubinaemia.

关键词： Hyperbilirubinaemia Hereditary Shunt