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On-line measurement of electrical variables of the transducer during ultrasonic welding and cutting
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作者 闫久春 刘井权 杨士勤 《China Welding》 EI CAS 2002年第2期133-137,共5页
A measurement system for high power electrical variables with ultrasonic frequency was established. It can measure the effective values of the voltage and the current, the active power, the phase difference of voltage... A measurement system for high power electrical variables with ultrasonic frequency was established. It can measure the effective values of the voltage and the current, the active power, the phase difference of voltage and current, the frequency of the transducer during ultrasonic welding and cutting. In sampling circuits of the system, the measured current is sensed by using a no capacitance and no inductance precision resistor and is treated with a difference amplifier, the measured voltage is processed by using a proportional amplifier. For achieving good amplitude frequency characteristics and rapid measurement of high frequency signals, the resistors, capacitors and amplifiers used in the system are rationally selected. Calibrating experiments show that relative errors are less than 1% for voltage and current effective values and less than 2.5% for active power, and absolute errors are ±1 Hz for frequency and ±1.7° for phase difference of voltage and current in the range of 17~23 kHz . 展开更多
关键词 ultrasonic welding ultrasonic cutting on line measurement electrical variables
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Smooth cutting pattern generation technique for membrane structures using geodesic line on subplane and spline interpolation 被引量:1
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作者 SHON Su-deok LEE Seung-jae LEE Kang-guk 《Journal of Central South University》 SCIE EI CAS 2013年第11期3131-3141,共11页
Practical techniques for smooth geodesic patterning of membrane structures were investigated.For the geodesic search,adjustment of the subplane of the extracted elements series was proposed,and various spline approxim... Practical techniques for smooth geodesic patterning of membrane structures were investigated.For the geodesic search,adjustment of the subplane of the extracted elements series was proposed,and various spline approximation methods were used to flatten the strip for the generation of a smooth pattern.This search approach is very simple,and the geodesic line could be easily attained by the proposed method without the need for a difficult computation method.Smooth cutting patterning can also be generated by spline approximation without the noise in discrete nodal information.Additionally,the geodesic cutting pattern saved about 21%of the required area for the catenary model due to the reduction of the curvature of the planar pattern seam line. 展开更多
关键词 membrane structures cutting pattern generation geodesic line spline interpolation triangular mesh sub-plane
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Innovation on Line Cut Methods of Self-aligned Multiple Patterning
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作者 Jeff Shu 《Journal of Microelectronic Manufacturing》 2019年第3期1-6,共6页
Self-aligned multiple patterning (SAMP) can enable the semiconductor scaling before EUV lithography becomes mature for industry use.Theoretically any small size of pitch can be achieved by repeating SADP on same wafer... Self-aligned multiple patterning (SAMP) can enable the semiconductor scaling before EUV lithography becomes mature for industry use.Theoretically any small size of pitch can be achieved by repeating SADP on same wafer but with challenges of pitch walking and line cut since line cut has to be done by lithography instead of self-aligned method.Line cut can become an issue at sub-30nm pitch due to edge placement error (EPE).In this paper we will discuss some recent novel ideas on line cut after self-aligned multiple patterning. 展开更多
关键词 SELF-ALIGNED MULTIPLE PATTERNING SAMP SELF-ALIGNED double PATTERNING SADP selfaligned quadruple PATTERNING SAQP line cut edge PLACEMENT error
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Preliminary Study on Water Demand Law of 1-0 Rooted Cuttings of Populus szechuanica
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作者 Dabuqiong Haoyu WANG +2 位作者 Huanhuan XIE Zhen XING Yanhui YE 《Meteorological and Environmental Research》 CAS 2021年第4期39-42,共4页
In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and ... In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and the law of water demand of P.szechuanica was grasped.In this paper,potted seedlings of 1-0 rooted cuttings of P.szechuanica were taken as research objects,and change situation of water consumption under different water control gradients was measured regularly by using weighing method,further analyzing dynamic change of water consumption of P.szechuanica and revealing water demand law of 1-0 rooted cuttings of P.szechuanica.The results showed that total change of water consumption of 1-0 rooted cuttings of P.szechuanica had"slow-fast-slow-fast"double-peak trend in the growth period of the current year,and corresponded with univariate linear relation(R^(2)=0.7137),with significant difference.In whole growth period,water consumption in August was the highest,which was 2.7 times of that in June and July and 1.5 times of that after September.In different water control treatments,the dynamic changes of daily and monthly water consumption were significantly different.In seven water control treatments,monthly water consumption was between(6315.95±1690.70)and(10105.28±3065.30)g/month,and mean was(8211.07±2308.23)g/month.With intensification of water control treatment,water consumption increased,but there was no seedling death due to water shortage.P.szechuanica has great plasticity in water demand,and can survive in both arid and humid environments.Meanwhile,it is revealed that P.szechuanica is the most widely distributed tree species in the region. 展开更多
关键词 Populus szechuanica 1-0 rooted cuttings Water consumption Water demand law
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Diagnosis of a submucosal mass at the staple line after sigmoid colon cancer resection by endoscopic cuttingmucosa biopsy
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作者 Mitsuaki Morimoto Koji Koinuma +6 位作者 Alan K Lefor Hisanaga Horie Homare Ito Naohiro Sata Yoshikazu Hayashi Keijiro Sunada Hironori Yamamoto 《World Journal of Gastrointestinal Endoscopy》 CAS 2016年第8期374-377,共4页
A 48-year-old man underwent laparoscopic sigmoid colon resection for cancer and surveillance colonoscopy was performed annually thereafter. Five years after the resection, a submucosal mass was found at the anastomoti... A 48-year-old man underwent laparoscopic sigmoid colon resection for cancer and surveillance colonoscopy was performed annually thereafter. Five years after the resection, a submucosal mass was found at the anastomotic staple line, 15 cm from the anal verge. Computed tomography scan and endoscopic ultrasound were not consistent with tumor recurrence. Endoscopic mucosa biopsy was performed to obtain a definitive diagnosis. Mucosal incision over the lesion with the cutting needle knife technique revealed a creamy white material, which was completely removed. Histologic examination showed fibrotic tissue without caseous necrosis or tumor cells. No bacteria, including mycobacterium, were found on culture. The patient remains free of recurrence at five years since the resection. Endoscopic biopsy with a cutting mucosal incision is an important technique for evaluation of submucosal lesions after rectal resection. 展开更多
关键词 SUBMUCOSAL tumor STAPLE line ENDOSCOPIC cutting-mucosa BIOPSY
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FEASIBILITY AND EXPERIMENT ANALYSIS OF FOUR-ROPES FRICTION HOIST WITHOUT ROPE GROOVES CUTTING
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作者 王广丰 张国忠 +2 位作者 佟刚 李文华 华青松 《Journal of Coal Science & Engineering(China)》 2000年第2期56-59,共4页
Based on theoretical analysis and experiment, when the difference between the ropes length is ensured, the radius difference between the rope grooves and the difference of the rope strain of a double rope friction hoi... Based on theoretical analysis and experiment, when the difference between the ropes length is ensured, the radius difference between the rope grooves and the difference of the rope strain of a double rope friction hoist will decrease with the increasing of hoisting times. Then the rope grooves cutting are not needed. If the connection form of the ropes or the structure of the frictional wheel of a four ropes friction hoist are changed into as a double ropes hoists, the hoist rope grooves will not need to be cut as well, and the working time will be saved and the service life of the rope lining will be lengthened also. 展开更多
关键词 friction hoist without rope grooves cutting abrasion of the rope lining service life of the rope lining
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融合Hough直线检测和Grab-cut的风机叶片自适应分割方法 被引量:7
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作者 唐震 彭业萍 +2 位作者 王伟江 曹广忠 吴超 《电子测量与仪器学报》 CSCD 北大核心 2021年第4期161-168,共8页
完整的边缘信息对风力发电机叶片的边缘缺陷检测至关重要,但由于户外采集的风机叶片图像背景复杂多样,现有图像分割算法的分割精度不足,无法保证边缘缺陷的完整性。因此,提出一种基于图像边缘特征与颜色信息的自适应图像分割方法实现风... 完整的边缘信息对风力发电机叶片的边缘缺陷检测至关重要,但由于户外采集的风机叶片图像背景复杂多样,现有图像分割算法的分割精度不足,无法保证边缘缺陷的完整性。因此,提出一种基于图像边缘特征与颜色信息的自适应图像分割方法实现风机叶片边缘检测。首先,使用Hough直线检测初步定位叶片直线边缘;然后,在目标区域应用基于Otus阈值分割和形态学运算的Grab-cut算法,实现叶片图像的自适应分割。采用无人机采集多个场景的图像作为测试样本,对分割方法与其他方法进行定性和定量对比分析。结果表明,该方法能自适应且准确地实现风机叶片图像分割,并保留边缘缺陷的完整性,其边缘覆盖率(0.9717)和边界位移误差(3.0403)指标均优于其他方法,对风机叶片的边缘缺陷检测具有重大潜在应用价值。 展开更多
关键词 风机叶片 无人机 图像分割 Hough直线检测 Grab-cut
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Detecting land subsidence near metro lines in the Baoshan district of Shanghai with multi-temporal interferometric synthetic aperture radar 被引量:4
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作者 Tao Li Guoxiang Liu +3 位作者 Hui Lin Rui Zhang Hongguo Jia Bing Yu 《Journal of Modern Transportation》 2014年第3期137-147,共11页
Land subsidence is a major factor that affects metro line (ML) stability. In this study, an improved multi- temporal interferometric synthetic aperture radar (InSAR) (MTI) method to detect land subsidence near M... Land subsidence is a major factor that affects metro line (ML) stability. In this study, an improved multi- temporal interferometric synthetic aperture radar (InSAR) (MTI) method to detect land subsidence near MLs is presented. In particular, our multi-temporal InSAR method provides surface subsidence measurements with high observation density. The MTI method tracks both point-like targets and distributed targets with temporal radar back- scattering steadiness. First, subsidence rates at the point targets with low-amplitude dispersion index (ADI) values are extracted by applying a least-squared estimator on an optimized freely connected network. Second, to reduce error propagation, the pixels with high-ADI values are classified into several groups according to ADI intervals and processed using a Pearson correlation coefficient and hierarchical analysis strategy to obtain the distributed targets. Then, nonlinear subsidence components at all point-like and distributed targets are estimated using phase unwrapping and spatiotemporal filtering on the phase residuals. The proposed MTI method was applied to detect land subsidence near MLs of No. 1 and 3 in the Baoshan district of Shanghai using 18 TerraSAR-X images acquired between April 21, 2008 and October 30, 2010. The results show that the mean subsidence rates of the stations distributed along the two MLs are -12.9 and -14.0 ram/year. Furthermore, three subsidence funnels near the MLs are discovered through the hierarchical analysis. The testing results demonstrate the satisfactory capacity of the proposed MTI method in providing detailed subsidence information near MLs. 展开更多
关键词 Multi-temporal InSAR - Subsidence Baoshan district - Shanghai Metro lines
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MiR-25-3p attenuates the proliferation of tongue squamous cell carcinoma cell line Tca8113 被引量:3
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作者 Jia-Ying Xu Li-Li Yang +3 位作者 Chao Ma Yuan-Liang Huang Gui-Xiang Zhu Qi-Lin Chen 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第9期743-747,共5页
Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stab... Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stably and highly express miR-25-3p using recombinant reiroviral vector-mediated gene transfer method.The proliferation of transfected Tca8113 was detected by thiazolyl blue tetrazolium bromide(MTT)and cell colony formation assays.eyclnD1,p21^(cipt)and p27^(kipt)mRNA expressions in the transfected Tca-8113 were detected by quantitative PCR.cyclinD1,p21^(cipt),p27^(kipt),AKT,p-AKT,FOXOt and p-FOX01 expressions in the transfected Tca8113 were detected by western blot analysis.In addition,miR-25-3p expression in the tongue squamous cell carcinoma cell line and tissue specimen was also detected by quantitative PCR.Results:Quantitative PCR showed that mitt-25-3p expression in the tongue squamous cell carcinoma cell lines and tissue specimen was significantly lower than that in the adjacent tissue.MTT and cell colony formation assays showed that after miR-25-3p overexpression,the proliferation of transfected Tca8113 was obviously attenuated.Western blot analysis and quantitative PCR showed that after miR-25-3p overexpression.p21^(cipt)and p27^(kipt)expressions were upregulated,while cyclinD1,AKT,FOXO1 expressions were downregulated,and AKT and FOXO1 phosphorylation was inactivated in the transfected Tca8113 cells.Conclusions:MiR-25-3p inhibited the proliferation of tongue squamous cell carcinoma cells and regulated cell cycle-related protein expression,playing an important role in the occurrence and development of squamous cell carcinoma of the tongue. 展开更多
关键词 MiR-25-3p Tongue SQUAMOUS CELL carcinoma Cellular PROLIFERATION RETROVIRUS Stable CELL line AKT/FOXO1
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Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage 被引量:2
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作者 Chuan-Zhi Cui Jian-Peng Xu +3 位作者 Duan-Ping Wang Zhi-Hong Liu Ying-song Huang Zheng-Ling Geng 《Petroleum Science》 SCIE CAS CSCD 2016年第2期272-279,共8页
Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to impro... Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %. 展开更多
关键词 Water-flooded reservoirs Layer regrouping.Flow resistance - High water cut Reservoir simulation
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Discovery of a variable broad absorption line in the BL Lac object PKS B0138-097 被引量:1
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作者 Shao-Hua Zhang Hui-Yuan Wang +2 位作者 Hong-Yan Zhou Ting-Gui Wang Peng Jiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第10期1163-1170,共8页
We report the discovery of a broad absorption line (BAL) of - 10^4 km s^-1 in width in the previously known BL Lac object PKS 0138-097, which we tentatively identified as an Mg II BAL. This is the first detection of... We report the discovery of a broad absorption line (BAL) of - 10^4 km s^-1 in width in the previously known BL Lac object PKS 0138-097, which we tentatively identified as an Mg II BAL. This is the first detection of a BAL, which is sometimes seen in powerful quasars with high accretion rates, in a BL Lac object. The BAL was clearly detected in its spectra spanning two epochs at a high luminosity state taken in the Sloan Digital Sky Survey (SDSS), while it disappeared in three SDSS spectra taken at a low luminosity state. The BAL and its variability pattern were also found in its historical multi-epoch spectra in the literature, but have been overlooked previously. In its high resolution radio maps, PKS 0138-097 shows a core plus a one- sided parsec-scale jet. The BAL variability can be interpreted as follows: The optical emission is dominated by the core in a high state and by the jet in a low state and the BAL material is located between the core and jet so that the BAL appears only when the core is shining. Our discovery suggests that outflows may also be produced in active galactic nuclei at a low accreting state. 展开更多
关键词 GALAXIES active -- galaxies absorption lines -- BL Lacertae objects individual (PKS 0138-097)
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Magneto-induced Line Broadening of Magneto-sensitive Lines in Solar Magnetized Atmospheres 被引量:1
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作者 Zhong-Quan Qu Shuai Wang +3 位作者 Cheng-Lin Xu Xiao-Yu Zhang Ming-Guo Sun Chun-Lan Jin 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第4期426-432,共7页
We analyze the spectral line broadening of those magneto-sensitive lines in solar magnetized atmospheres. The broadening at the line wings is due to the increase of the effective width of energy levels involved in Zee... We analyze the spectral line broadening of those magneto-sensitive lines in solar magnetized atmospheres. The broadening at the line wings is due to the increase of the effective width of energy levels involved in Zeeman splitting,and the broadening at the line core also originated in Zeeman splitting under the condition that the Zeeman components are mixed. Therefore, the magneto-induced or Zeeman broadening take effects on the whole line. The observed Stokes parameter data in a sunspot and outside it acquired by Solar Stokes Spectrum Telescope (S^3T) are analyzed for the demonstration of this mechanism, and the Zeeman broadening rates are calculated for Fe16302.5 under some assumptions.Our result shows that the broadening is increased as the magnetic field strength becomes stronger, but the rate of increase at the line core is decreased as the field strength increases, while the rate at the wing does not show such an obvious regularity. The broadening is more effective in the line core than in the wings. 展开更多
关键词 sunspots - line profiles-magnetic fields - radiative transfer-polarization
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Line Broadening in a Limb Flare: Derivation of Macro-turbulent Velocity Fields 被引量:1
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作者 Ying Liu and Ming-De DingDepartment of Astronomy, Nanjing University, Nanjing 210093 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2002年第3期277-286,共10页
The line profiles of Ha in a limb flare on 1998 November 11 appear to be unusually broadened. It is considered that macro-turbulence (or macroscopic mass motions) may be one of the main causes. We use an inversion tec... The line profiles of Ha in a limb flare on 1998 November 11 appear to be unusually broadened. It is considered that macro-turbulence (or macroscopic mass motions) may be one of the main causes. We use an inversion technique to extract the probability distribution of the line-of-sight velocity in the flare. There exist some differences between the velocity distributions deduced from Ha and from Ca II λ8542, which may be because the two lines depend differently on the temperature and velocity. Since the loop density is high, we obtain a rather short cooling time (several tens of seconds) from the hot X-ray loops to the cool loops visible in Ha. Possible origins of the large scale motions are discussed. 展开更多
关键词 Sun: flares - Sun: atmospheric motions - line: profiles
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Effect of Cutting Speed on Surface Quality by Bandsawing
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作者 于建国 LiangkaiTING 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第4期246-249,共4页
The surface profile behavior of workpieces sawn has been investigated. Six species were sawn under the condi-tion of four different kinds of cutting speed by the band saw. The real surface profile of a sawn workpiecc ... The surface profile behavior of workpieces sawn has been investigated. Six species were sawn under the condi-tion of four different kinds of cutting speed by the band saw. The real surface profile of a sawn workpiecc is composed of twosections, which arc the additivity of the waviness of filtered wave and roughness curve. The roughness of center line avernge aswell as amplitude decrease with the increasing of cutting speed for different kinds of species used in the experiment. 展开更多
关键词 Band saw. cutting speed. Profile curve. WAVINESS or filtered wave. ROUGHNESS CURVE ROUGHNESS of center line AVERAGE
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THE DIFFERENTIATION OF HUMAN GASTRIC ADENOCAR-CINOMA CELL LINE MGc80-3 INDUCED BY DIBUTYRYL cAMP IN VITRO 被引量:2
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作者 李祺福 汪德耀 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第1期7-13,共7页
For providing some experimental basis in establishing malignant phenotypic reversed indexes of gastric carcinoma cells, human gastric adenocar-cinoma cell line MGc80-3 was induced by dBcAMP in vitro to appraise the ef... For providing some experimental basis in establishing malignant phenotypic reversed indexes of gastric carcinoma cells, human gastric adenocar-cinoma cell line MGc80-3 was induced by dBcAMP in vitro to appraise the effect of gastric carcinoma cell differentiation by chemical inducers.Under light microscope, MGc80-3 cells, after treated with 1 mM dBcAMP, tended to be flat and disperse, and their volume gradually enlarged, with their uncleus relatively smaller and their shape rather regular. Morphological changes, like norma differentiated epithelial cells, were observed. The cells attached firmly, grew slowly, their growth curve showed inhibitory rate amounted to 52.87%, and cellular division exponent displayed their peak value 1.5 times less than that of MGc80-3 cells. It was clear that dBcAMP could effectively inhibit the multiplication activity of MGc80-3 cells. After dBcAMP treatment, remarkable changes of cell surface charges was indicated by cell electrophoresis, the ratio dropped to 3.043 from 3.988, and their re-tardant ratio reached up to 31.2%. cAMP content in cells after this treatment, detected by cAMP and cGMP radioimmunoassay, was enhanced by 2.42 times, and cAMP/cGMP ratio, by 1.73 times. Thus, cAMP level within MGc80-3 cells was raised obviously by dBcAMP. Heterotransplantation experiments showed that tuntorigenic rate of MGc80-5 cells (transplanted subcutaneously to BALB/c mice) amounted to 100%, and that of the cells after this treatment was only 5.6%. Their tumorigenic ability was extremely reduced.These results confirmed that dBcAMP was able to change malignant phenotypic characteristics of MGc80-3 cells and produce a reversed alteration: Thus, it has a remarkable inductive effect in differentiating gastric carcinoma cells. All these characteristics were also considered as the reference indexes in appraising reversed effect for the homologous cancer cells. 展开更多
关键词 THE DIFFERENTIATION OF HUMAN GASTRIC ADENOCAR-CINOMA CELL line MGc80-3 INDUCED BY DIBUTYRYL cAMP IN VITRO
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A search for evidence of small-scale inhomogeneities in dense cores from line profile analysis
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作者 Lev Pirogov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第8期97-102,共6页
In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming... In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model. 展开更多
关键词 lineS profiles - molecular data - methods data analysis - ISM clouds - ISM molecules - ISM structure - ISM individual objects (S 140)
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ESTABLISHMENT OF A MAMMARY CANCER CELL LINE Ca 761-86 AND ITS BIOLOGICAL CHARACTERISTICS IN INBRED 615 MICE
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作者 程一棹 黄敏 +5 位作者 王明俭 郑怀祖 袁保和 许广源 程佳 钱振超 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期43-48,共6页
A cell line designated as Ca 761-86 has been established from the solid mouse mammary cancer (Ca 761) by suspension culture. It has been passaged for more than 212 generations. Moderate round cells were predominant an... A cell line designated as Ca 761-86 has been established from the solid mouse mammary cancer (Ca 761) by suspension culture. It has been passaged for more than 212 generations. Moderate round cells were predominant and most of them were mononuclear. Some characteristics of malignant cells and A-type viral-like particles were observed by electron microscopy. The results of cytochemical studies (DNA, RNA, SDH, 5' AMPase, ACP etc.) were comparable to the ultramicroscopic results. It multiplied approximately 27.4 fold on day 5 with mitotic index reaching 1.8% on day 3. This cell line was a hyperdiploid with karyotype of 45 or 45, -2X, tril2, tri17, +M1-5. Cell agglutination was observed when treated with ConA (≥7 fig, ml). Spontaneous agglutination might also take place without adding any ConA. After 5×106 cells of Ca 761-86 suspension were transplanted into the normal inbred 615 mice by different ways (subcutan eous, intrafoot-pad or intraperitoneal), the transplan lability rate reached 100%. Spontaneous remission was never observed and its metastatic ability reserved. PPLO were not detected. Ca 761-86 may be of value for practical purposes. 展开更多
关键词 line ESTABLISHMENT OF A MAMMARY CANCER CELL line Ca 761-86 AND ITS BIOLOGICAL CHARACTERISTICS IN INBRED 615 MICE RER ConA CA
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Strong optical and UV intermediate-width emission lines in the quasar SDSS J232444.80–094600.3:dust-free and intermediate-density gas at the skin of dusty torus?
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作者 Zhen-Zhen Li Hong-Yan Zhou +3 位作者 Lei Hao Shu-Fen Wang Tuo Ji Bo Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第9期107-116,共10页
Emission lines from the broad emission line region (BELR) and the narrow emission line region (NELR) of active galactic nuclei (AGNs) have been extensively studied. However, emission lines are rarely detected be... Emission lines from the broad emission line region (BELR) and the narrow emission line region (NELR) of active galactic nuclei (AGNs) have been extensively studied. However, emission lines are rarely detected between these two regions. We present a detailed analysis of quasar SDSS J232444.80-094600.3 (SDSS J2324-0946), which is remarkable for its strong intermediate-width emission lines (IELs) with FWHM ≈ 1800 km s^-1. The IEL component is present in different emission lines, including the permitted lines Lyαλ1216, CⅣ λ1549, semiforbidden line C Ⅲ] λ1909, and forbidden lines [OⅢ] ss4959, 5007. With the aid of photo-ionization models, we found that the IELs are produced by gas with a hydrogen density of nH - 10^6.2 -- 10^6.3 cm^-3, a distance from the central ionizing source of R - 35 - 50 pc, a covering factor of - 6%, and a dust-to-gas ratio of ≤ 4% that of the SMC. We suggest that the strong IELs of this quasar are produced by nearly dust-free and intermediate-density gas located at the skin of the dusty torus. Such strong IELs, which serve as a useful diagnostic, can provide an avenue to study the properties of gas between the BELR and the NELR. 展开更多
关键词 GALAXIES active -- galaxies nuclei -- quasars emission lines -- individual (SDSSJ2324-0946)
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Effect of DRB on the Biological Characteristics of Human Laryngeal Carcinoma Hep-2 Cell Line
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作者 王建亭 龚树生 +3 位作者 付勇 薛秋红 陈广理 刘英鹏 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第1期104-106,共3页
In order to study the effect of 5, 6-Dichloro-l-13-D-ribofuranosyl-benzimidazole (DRB) on the biological characteristics of human laryngeal carcinoma Hep-2 cell line in vitro, Hep-2 cells cultured in vitro were trea... In order to study the effect of 5, 6-Dichloro-l-13-D-ribofuranosyl-benzimidazole (DRB) on the biological characteristics of human laryngeal carcinoma Hep-2 cell line in vitro, Hep-2 cells cultured in vitro were treated with different concentrations of DRB. Changes in cell proliferation, apoptotic rate and invasiveness were detected by MTT assay, flow cytometry (FCM) and matrigel in vitro invasion assay, respectively. It was found that DRB inhibited the proliferation of Hep-2 cells in a dose- and time-dependent manner. After being treated with 0, 10, 20, 40, 80 μmmol/L DRB for 24 h, the apoptotic rate in Hep-2 cells was (0.68±0.19)%, (1.95±0.12)%, (8.51±0.26)%, (11.26±0.17)% and (14.99±0.32)%, respectively. The matrigel in vitro invasion assay revealed that DRB began to inhibit the invasion of Hep-2 cells at the concentration of 5 μmmol/L, and with the increase of DRB concentration, the inhibitory effect was enhanced. It was suggested that DRB could influence the essential biological characteristics of Hep-2 cells, inhibit Hep-2 cells proliferation, reduce invasive ability and induce apoptosis of Hep-2 cells. 展开更多
关键词 protein-serine-threonine kinases 5 6-Dichloro-1-β-D-ribofuranosyl- benzimidazole laryngeal neoplasms Hep-2 cell line
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Relation between Starlight and Nebular Emission Lines of Star-Forming Galaxies
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作者 Hong-LinLu Hong-YanZhou +4 位作者 Ting-GuiWang Zhen-QuanZhuang Xiao-BoDong Jun-XianWang ChengLi 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第3期221-228,共8页
We present an exercise that intends to establish a relationship between the strength of nebular emission lines and optical stellar features in the spectrum of a galaxy. After accurately subtracting the stellar continu... We present an exercise that intends to establish a relationship between the strength of nebular emission lines and optical stellar features in the spectrum of a galaxy. After accurately subtracting the stellar continuum and the underlying stellar absorption, we made reliable measurements of the emission lines of all the galaxies in the Sloan Digital Sky Survey Data Release 2 (SDSS DR2). More than 4000 star-forming galaxies with high S/N ratio of both the stellar spectrum and the emission lines are selected. These galaxy spectra are fitted with the 10 PCs of Yip et al., after all the emission line regions have been filtered out. We find that the flux of hydrogen Balmer emission lines, Ha and Hβ can be well recovered from the PCs, while the metal lines are not well reproduced. The fluxes of Ha and Hβ measured from the PC-reconstructed spectra and from the observed spectra agree well with an rms scatter of only - 0.1 dex. This result suggests that, with moderate spectral resolution and S/N ratio, the optical stellar spectrum of a galaxy can serve as an indicator of star formation rate. 展开更多
关键词 galaxies: fundamental parameters - galaxies: starburst - radiation: lines CONTINUUM
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