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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

Corrosion Behavior of Welded Joints for Cargo Oil Tanks of Crude Oil Carrier

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Journal of Iron and Steel Research International 2016年第9期23卷 955-962页

作者： jin-shan wei Yan-chang QI Zhi-ling TIAN Yun PENG State Key Laboratory of Advanced Steel Processes and Products Central Iron & Steel Research Institute

E32 grade corrosion resistant steel was welded with welding wires with three different S contents. The mi crostructure, mechanical properties, inclusions, and corrosion behavior of welded joint were investigated. The joint coupon corrosion test and potentiodynamic polarization test were carried out under the simulated corrosion environ- ment of the inner bottom plates of cargo oil tanks. The pitting initiation and propagation mechanism of the weld metal were studied by scanning electron microscopy and infinite focus. The results indicated that the microstructures of three kinds of weld metals are all composed of acicular ferrite, ferrite side-plate and proeutectoid ferrite. The micro- structure of heat affected zone is composed predominantly of bainite. Joint welded with low S filler wire has good me- chanical properties. S can decrease free corrosion potential and increase the corrosion tendency. The pitting initiation is oxide inclusion or sulfide oxide inclusion complex. S can induce the formation of occluded area and promote the corrosion propagation. The chemical compositions of weld metal is similar to base metal, which can limit the galvanic corrosion between weld metal and base metal, and avoid formation of corrosion step.

关键词： cargo oil tank welded joint pit corrosion corrosion step

In situ measurement of environmental γ radiation dose rates of key nuclides for large radioactive surface sources

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Nuclear Science and Techniques 2025年第1期36卷 69-79页

作者： Ze-Qian Wu Jian Sun wei-Qi Huang Bai-Rong Wang jin-Xing Cheng Jiang-Feng Wu Yong-Hong Wang Biao Yuan Sheng Qi Kun shan Institute of NBC Defence Beijing 102205China Beijing New-High Technology Academy Beijing 100094China

To monitor nuclear and radiation emergencies,it is crucial to obtain accurate in situ measurements of the environmentalγ radiation dose rate from key radionuclides,particularly for large radioactive surface *** methods currently used for measuring dose rates are inadequate for obtaining the dose rates of key radionuclides and have large angular response errors when monitoring surface *** address this practical problem,this study proposes three methods for measuring the dose rate:the weighted peak total ratio,mean value regression,and numerical integration *** methods are based on energy-spectrum measurement data,and they were theoretically derived and numerically ***,a 1-m-long hexagonal radioactive surface source was integrated into a larger surface *** situ measurement experiments were conducted on a large radioactive surface source using a dose-rate meter and a portable HPGespectrometer to analyze the errors of the three aforementioned methods and verify their validity.

关键词： Environmentalγradiation dose rate HPGespectrometer Key radionuclides Radioactive surface source

Trichobitacin-a new ribosome-inactivating protein Ⅰ.The isolation,physicochemical and biological properties of trichobitacin

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Chinese Journal of Chemistry 1997年第2期15卷 160-168页

作者： jin,shan-wei XIANG,Bang-Ping CAO,Bai-Xun WANG,Yu shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,shanghai 200032,China

From the press-residue of the fresh root tuber of Trichosanthes kirilowii Maxim (Cu-curbitaceae),a new ribosome-inactivating protein (RIP),trichobitacin,was *** has the activity of RNA N-glycosidase and can inhibit the growth of human placental trophoblastic *** molecular weight is 27,228 Da (ES-MS) and pI *** is a single chain basic *** amino acid composition was *** is a new *** consists of 0.7~0.9% galactose and may be a *** A'-and C-terminal amino acid is Asp and Ala,*** N-terminal preliminary amino acid sequence has been determined.

关键词： Trichobitacin ribosome-inactivating protein trichosantbin protein isolation Trichosanthes kirilowii Maxim

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： shan Ping Yu Emily Choi Michael QJiang Ling wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Association between inflammatory mediators and angiographic morphologic features indicating thrombus formation in patients with acute myocardial infarction

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Chinese Medical Journal 2009年第15期122卷 1738-1742页

作者： LI Dong-bao HUA Qi LIU Zhi LI jing XU Li-qing WANG shan jin wei-ying Department of Cardiology Xuanwu Hospital of Capital Medical University Beijing 100053 China

Background Inflammatory mechanisms had played an important role in the occurrence and prognosis of acute myocardial infarction, inflammatory mediators was associated with adverse outcomes of acute myocardial infarction. This study tested the hypothesis that in the acute phase of myocardial infarction with ST-segment elevation, neutrophil count and high-sensitivity C-reactive protein are predictive of angiographic morphologic features that indicate thrombus formation in the infarct-related artery. Methods This retrospective study included 182 consecutive patients with acute myocardial infarction and ST-segment elevation. Patients were assigned to a thrombus-formation group （n=77） and a non-thrombus-formation group （n=-106）. All patients had a Killip＇s classification 〈3 and onset 〈12 hours prior to presentation. All the cases were going to undergo coronary angiography, including primary percutaneous coronary intervention, simple coronary angiography, or thrombolysis in a coronary artery （or arteries） or coronary artery bypass graft（s）. Blood samples for measurement of high-sensitivity C-reactive protein and for routine blood laboratory studies were collected prior to coronary angiography. Results The levels of high-sensitivity C-reactive protein, total leukocyte counts, neutrophil counts, and neutrophil/ lymphocyte ratios were substantially higher in the thrombus-formation group than in the non-thrombus-formation group patients （for each, P 〈0.05）. Stepwise Logistic regression analyses identified high-sensitivity C-reactive protein, neutrophil count, and neutrophil/lymphocyte ratio as independent predictors of thrombus formation in the infarct-related artery （for each, P 〈0.05）. Conclusions In patients with acute myocardial infarction levels of high-sensitivity C-reactive protein are predictors to higher neutrophil counts, neutrophil/lymphocyte ratio, and ndicate thrombus formation

关键词： acute myocardial infarction thrombosis neutrophil percutaneous coronary intervention C-reactive protein

天花粉蛋白的故事——中药现代化的一个成功实例

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生命的化学 2006年第6期26卷 564-567页

作者：金善炜中国科学院上海有机化学研究所 200032

天花粉蛋白是我国独创的用于计划生育,治疗宫外孕、恶性葡萄胎和艾滋病等的良药。该文简要回顾了天花粉蛋白从复方到单方,从外用到针剂的研究历史,在应用研究和基础研究方面,都取得了重大成果,是用现代科学技术促进中药现代化的一个成... 详细信息

天花粉蛋白是我国独创的用于计划生育,治疗宫外孕、恶性葡萄胎和艾滋病等的良药。该文简要回顾了天花粉蛋白从复方到单方,从外用到针剂的研究历史,在应用研究和基础研究方面,都取得了重大成果,是用现代科学技术促进中药现代化的一个成功实例。

关键词：天花粉天花粉蛋白引产人类艾滋病毒(HIV)

Achieving further refinement of grain structure and improvement of mechanical properties in Al-12Si-4Cu-2Ni-1Mg alloy by Al-Ti-C-B master alloy addition and deep cryogenic treatment

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China Foundry 2025年第1期22卷 75-82页

作者： Lin-fei Xia Wen-bo Li Zuo-shan wei Yu-ying Wu Xiang-fa Liu China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China shandong Key Laboratory of Advanced Aluminum Materials and Technology Binzhou Institute of TechnologyBinzhou 256600ShandongChina

Near-eutectic Al-Si alloys are widely used in automotive manufacturing due to their superior wear resistance and high temperature *** of high Si content,the grain refinement of near-eutectic Al-Si alloy has been a problem for many *** this study,the effect of deep cryogenic treatment(DCT)on the microstructure and mechanical properties of Al-12Si-4Cu-2Ni-Mg alloy with addition of Al-Ti-C-B master alloy was fully *** show that the average grain size of the alloy is greatly reduced from 0.92 mm to 0.50 mm,and the eutectic Si and Al7Cu4Ni precipitates are spheroidized and refined in Al-12Si-4Cu-2Ni-Mg after DCT for 24 h and aging *** these changes of microstructures result in a significant increment of about 22.5%in elongation and a slight enhancement of about 6.8%in tensile ***,the refinement of microstructure also significantly improves the fatigue life of the alloy.

关键词： deep cryogenic treatment near-eutectic Al-Si master alloy microstructure mechanical properties

Multi-channel microelectrode arrays for detection of single-cell level neural information in the hippocampus CA1 under general anesthesia induced by low-dose isoflurane

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Fundamental Research 2025年第1期5卷 72-81页

作者： Hu, Ruilin Fan, Penghui Wang, Yiding shan, jin jing, Luyi Xu, wei Mo, Fan Wang, Mixia Luo, Yan Wang, Ying Cai, Xinxia Luo, jinping State Key Laboratory of Transducer Technology Aerospace Information Research Institute Chinese Academy of Science Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Department of Anesthesiology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China

Timely monitoring of anesthesia status during surgery is important to prevent an overdose of isoflurane anesthesia. Therefore, in-depth studies of the neural mechanisms of anesthetics are warranted. Hippocampal CA1 plays an important role during anesthesia. Currently, a high spatiotemporal resolution microdevice technology for the accurate detection of deep brain nuclei is lacking. In this research, four-shank 32-channel implantable microelectrode arrays (MEAs) were developed for the real-time recording of single-cell level neural information in rat hippocampal CA1. Platinum nanoparticles were modified onto the microelectrodes to substantially enhance the electrical properties of the microelectrode arrays. The modified MEAs exhibited low impedance (11.5 ± 1 kΩ) and small phase delay (-18.5° ± 2.54°), which enabled the MEAs to record single-cell level neural information with a high signal-to-noise ratio. The MEAs were implanted into the CA1 nuclei of the anesthetized rats, and the electrophysiological signals were recorded under different degrees of anesthesia mediated by low-dose concentrations of isoflurane. The recorded signals were analyzed in depth. Isoflurane caused an inhibition of spike firing rate in hippocampal CA1 neurons, while inducing low-frequency oscillations in CA1, thus enhancing the low-frequency power of local field potentials. In this manner, the spike firing rate and the power of local field potentials in CA1 could characterize the degree of isoflurane anesthesia. The present study provides a technical tool to study the neural mechanisms of isoflurane anesthesia and a research method for monitoring the depth of isoflurane anesthesia in clinical practice. © 2023

关键词： Hippocampal CA1 Isoflurane anesthesia Local field potentials Micro electrode array Spike

Expression of vascular endothelial growth factor and its role in oncogenesis of human gastric carcinoma

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World Journal of Gastroenterology 2001年第4期7卷 500-505页

作者： Du-Hu Liu Xue-Yong Zhang Dai-Ming Fan Yu-Xin Huang jin-shan Zhang wei-Quan Huang Yuan-Qiang Zhang Qing-Sheng Huang Wen-Yu Ma Yu-Bo Chai Ming jin Institute of Digestive Disease,Xijing Hospital,~2 Department of Gastroenterology,Tangdu Hospital,~3Department of Histology and Embryology,~4 Department of Microbiology,~5 Department of Biochemistry,Fourth Military Medical University,Xi’an 710033,Shaanxi Province,China Institute of Combined Injury Third Military Medical University Chongqing 400038 China. liuduhu@***

AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P<0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P<0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P<0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P<0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.

关键词： Gene Expression Regulation, Neoplastic Adult Aged Animals Cell Division Cloning, Molecular DNA, Antisense DNA, Complementary Endothelial Growth Factors Endothelium, Vascular Female Humans Lymphokines Male Mice Mice, Nude Middle Aged Neovascularization, Pathologic Receptor Protein-Tyrosine Kinases Receptors, Growth Factor Receptors, Vascular Endothelial Growth Factor Stomach Neoplasms Transfection Tumor Cells, Cultured Vascular Endothelial Growth Factor A Vascular Endothelial Growth Factors