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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan qing-tao guo Kai-lun Zhang Fu-zhi Yu Yu-ying Li Yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Effects of broth culture filtrate protein of VacA^＋ Helicobacterpylori on the proliferation and apoptosis of gastric epithelial cells

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Chinese Medical Journal 2013年第11期126卷 2168-2173页

作者： ZHAO Yu-qing guo tao QIAN Jia-ming Department of Gastroenterology Peking Union Medical CollegeHospital Chinese Academy of Medical Sciences Beijing 100730China

Background Infection with Helicobacter pylori （H. pylon） may lead to chronic inflammation of the stomach epithelium, mucosal atrophy, imbalance of proliferation and apoptosis of epithelial cells; resulting in chronic gastritis, peptic ulcer, gastric cancer, and many other clinical outcomes. Why and how H. pylorus leads to gastric cancer is not clear yet. Through in vitro experiments, this study evaluated the effects of broth culture filtrate protein （BCF-P） from the supernatant of liquid culture media of H. pylori on proliferation and apoptosis of immortalized human gastric epithelial cell lines （GES-1）and gastric cancer cell lines （AGS）. Methods For the study, GES-1 and AGS cell lines mix with BCF-P and epidermal growth factor （EGF）. MTT assay and flow cytometry （FCM） determined the levels of proliferation and apoptosis. Detected expression levels of cyclooxygenase-2 （COX-2） and Fas mRNA by reverse transcription （RT）-PCR. Also did analysis of the effects of BCF-P on epidermal growth factor receptor （EGFR） tyrosine kinase activity of GES-1 and AGS cells by non-radioactive enzyme-linked assay. The Student＇s t test and one-way analysis of variance （ANOVA） were used for statistical analysis. Results BCF-P inhibited proliferation of GES-1 and AGS cells in a concentration-dependent manner. The inhibition rates are respectively 68.7% in AGS and 61.4% in GES-1. With the same dose and time for inhibiting the proliferation, BCF-P failed to induce apoptosis of GES-1 and AGS cells. Effects of BCF-P reduced the expression of Fas mRNA of GES-1 and AGS cells （P 〈0.05）. This is consistent with the effects of EGF. BCF-P reduced the expression of COX-2 mRNA of AGS cells （P 〈0.05）. This is opposite to the effects of EGF （P 〈0.05）. Effects of BCF-P improved more than three times the EGFR tyrosine kinase activity of GES-1 and AGS cells. Conclusions BCF-P inhibited the proliferation of AGS and GES-1 cells in vitro, unrelated to apoptosis. Effects of BCF-P on gastric epithelial cells in

关键词： gastric epithelial cells Helicobacter pylori vacuolated cytotoxic proliferation apoptosis

Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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Journal of Energy Chemistry 2025年第1期100卷 710-720页

作者： Wenxuan Chen Xiu-qing Qiao guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian Wu tao Wu Dong-Sheng Li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges Laboratory College of Chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-CdS/Mo2C@C heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the CdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-CdS （c-CdS） and hexagonal-CdS （h-CdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-CdS phase junction to realize gradient charge ***,the photothermal effect of Mo2C@C helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-CMC photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of CdS by constructing plasmonic tandem heterogeneous junctions.

关键词： Heterojunctions LSPR Photocatalyst Phase junction Schottky junction Photothermal effect

Ancient Art Retains Splendor in New Era

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China Today 2025年第1期74卷 74-75页

作者： guo qing 不详

With government support,more young people are studying Thangka art,securing its innovative *** 1,300-year-old Thangka art,religious painting on woven material,has been lauded as an illustrated encyclopedia of Tibetan *** unique artistic and cultural value earned it a place on China’s intangible cultural heritage list in *** institution tasked with preserving and developing this ancient art is the Tibet Academy of Thangka(TAT)in *** focuses on the Mansar School of Thangka *** can observe the whole process of creating a Mansar Thangka piece,from sketching to adding the final touch.

关键词： religious earned sketch

China-India: Ties that Bind

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China Today 2025年第1期74卷 59-61页

作者： guo qing 不详

From international student to professor,Tripathi Mani shares his thoughts on Chinese and Indian cultures and the beneficial exchanges between *** Vivek Mani first learned about China from bedtime stories told by his father,a Sanskrit teacher in rural Bihar,a state in east *** of the stories were about the Chinese monk Xuanzang’s adventures during his long journey to India to find Buddhist *** kindled the young boy’s interest in China and the desire to visit it one day.

关键词： India Indian desire

Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 92-101页

作者： Zongyou Cheng qing Zhao Mengjie tao Jijun Du Xingxi Huang Chengjun Liu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical *** controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower *** this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen *** phases and magnetic properties of FeCoNi medium entropy alloy were *** showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal *** alloy prepared by hydrogen reduction was uniform and showed a relatively high ***,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.

关键词： medium entropy alloy sol-gel co-precipitation carbothermal hydrogen reduction

The School that Changes Mindsets

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China Today 2025年第1期74卷 62-64页

作者： guo qing KONG SIQI 不详

China’s highest-altitude primary school is not only teaching children of farmers and herders but their parents as *** Sinopec Primary School in Nagqu,a city in Xizang Autonomous Region in southwest China,is known as the school“the closest to the sky”due to its high-altitude location-a breathtaking 4,700 meters above sea *** by oil and gas giant Sinopec as part of its corporate social responsibility,the school opened in 2012 and has since become a microcosm of China’s drive for education,especially in remote and rural areas,to ensure that no one is left behind.

关键词： altitude farmers southwest

基于BP神经网络的智慧城市建设水平评价研究

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数学的实践与认识 2018年第14期48卷 64-72页

作者：马庆涛尚国琲焦新颖河北地质大学土地资源与城乡规划学院

智慧城市建设是一个城市先进性的体现，智慧城市建设水平评价对于城市建设具有重要意义．以石家庄为例，构建由12个指标构成的评价体系，运用样本数据训练BP神经网络模型，评定出2011—2016年智慧城市建设水平等级，给出结论与建议．结... 详细信息

智慧城市建设是一个城市先进性的体现，智慧城市建设水平评价对于城市建设具有重要意义．以石家庄为例，构建由12个指标构成的评价体系，运用样本数据训练BP神经网络模型，评定出2011—2016年智慧城市建设水平等级，给出结论与建议．结果表明：石家庄城市智慧度较低但整体呈上升趋势，2016年上升比较明显，预计未来智慧建设水平继续提升．建议完善城市基础设施建设、增加科技创新投入、加强智慧政务能力，为石家庄智慧城市建设提供帮助．

关键词：石家庄市智慧城市智慧城市建设 BP神经网络

慢性缺氧对大鼠肺内细胞增殖、凋亡及相关基因表达的影响

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中国病理生理杂志 1999年第5期15卷 459-461页

作者：陶清国张珍祥徐永健同济医科大学附属同济医院呼吸研究室

目的：探讨慢性缺氧性肺动脉高压肺血管结构改建（ｐｕｌｍｏｎａｒｙｖａｓｃｕｌａｒｓｔｒｕｃｔｕｒａｌｒｅｍｏｄｅｌｉｎｇ，ＰＶＳＲ）的细胞及分子机制。方法：大鼠慢性缺氧模型复制，免疫组化及Ｎｏｒｔｈｅｒｎ杂交检测大鼠... 详细信息

目的：探讨慢性缺氧性肺动脉高压肺血管结构改建（ｐｕｌｍｏｎａｒｙｖａｓｃｕｌａｒｓｔｒｕｃｔｕｒａｌｒｅｍｏｄｅｌｉｎｇ，ＰＶＳＲ）的细胞及分子机制。方法：大鼠慢性缺氧模型复制，免疫组化及Ｎｏｒｔｈｅｒｎ杂交检测大鼠肺内ｃ－ｍｙｃ及ｂｃｌ－２两基因蛋白及ｍＲＮＡ的表达，免疫组化及原位缺口末端标记法检测大鼠肺内增殖相关抗原Ｋｉ－６７及凋亡细胞。结果：正常及慢性缺氧大鼠肺内均检出一定比率的增殖或凋亡细胞，缺氧１、２周大鼠肺内细胞增殖／凋亡比值比对照组分别增高约３、３５倍。与细胞增殖、凋亡密切相关的ｃ－ｍｙｃ、ｂｃｌ－２基因表达在缺氧１周大鼠肺内显著增高，在缺氧２周更显著。结论：细胞增殖、凋亡机制共同参与了慢性缺氧性肺动脉高压时ＰＶＳＲ的调节。

关键词：大鼠肺动脉高压缺氧细胞增殖细胞凋亡

中国已婚育龄妇女性生活频度及其影响因素分析

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复旦学报（医学版） 2001年第6期28卷 526-530页

作者：陈锡宽高尔生武俊青陶建国上海市计划生育科学研究所流行病室上海200032

目的　了解我国已婚育龄妇女的性生活频度 ,探讨影响性生活频度的因素 ,为提高妇女生殖健康水平提供科学依据。方法　利用 1997年全国人口与生殖健康调查资料 ,对我国已婚育龄妇女的性生活频度及其影响因素进行了分析。结果　月性生活... 详细信息

目的　了解我国已婚育龄妇女的性生活频度 ,探讨影响性生活频度的因素 ,为提高妇女生殖健康水平提供科学依据。方法　利用 1997年全国人口与生殖健康调查资料 ,对我国已婚育龄妇女的性生活频度及其影响因素进行了分析。结果　月性生活频度中位数为 4次 ,90 %的可信限为 1～ 12次。户口性质、民族、年龄、婚龄、是否定期参加妇科检查、怀孕史、流产史、性生活满意度、性生活中妇女的地位等影响性生活的频度。结论　性生活频度不仅受到人口学特征和生理因素的影响。

关键词：已婚妇女育龄妇女性生活频度性生活满意度