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Monitoring of Karst Rocky Desertification Control Projects Based on Remote Sensing Images with Medium and High Spatial Resolution——A Case Study of Disi River Basin in Puan County 被引量:1
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作者 Haixiang Guo Yulun An 《Meteorological and Environmental Research》 CAS 2013年第7期32-34,38,共4页
[ Objective] The study aimed to improve methods of monitoring Karst Rocky Desertification (KRD) control projects and increase the working efficiency. [Method] Based on remote sensing images with medium and high spat... [ Objective] The study aimed to improve methods of monitoring Karst Rocky Desertification (KRD) control projects and increase the working efficiency. [Method] Based on remote sensing images with medium and high spatial resolution, KRD control projects in Disi River basin in Puan County were monitored, that is, information of the project construction in the study area was extracted using supervised classification and hu- man-computer interactive interpretation, and the monitoring results were testified with the aid of GPS. [Result] It was feasible to monitor KRD con- trol projects in Disi River basin based on remote sensing images with medium and high resolution, and the monitoring accuracy was satisfactory, reaching above 80% or 90%, so the method is worthy of popularizing. [ Conclusion] Remote sensing images with medium and high resolution can be used to monitor other KRD control Droiects. 展开更多
关键词 Karst Rocky Desertification (KRD) Remote sensing images with medium and high spatial resolution MONITORING Puan County China
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Case report:simultaneous femtosecond laser astigmatic keratotomy and toric intraocular lens implantation in femtosecond laser-assisted cataract surgery in a patient with surgically induced high corneal astigmatism
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作者 Yan Guo Heather Edwards +2 位作者 Mark Woodward Tyrone Curtis Gresham Kayla Morgan 《Annals of Eye Science》 2022年第4期69-76,共8页
Background:Femtosecond laser astigmatic keratotomy(FSAK)and toric intraocular lens(IOL)implantation have been studied individually for comparison to treat astigmatism at cataract surgery.We report a case of surgically... Background:Femtosecond laser astigmatic keratotomy(FSAK)and toric intraocular lens(IOL)implantation have been studied individually for comparison to treat astigmatism at cataract surgery.We report a case of surgically induced high corneal astigmatism by laser thermal keratoplasty(LTK)in a patient with cataract who was successfully treated with simultaneous combination of FSAK and toric IOL implantation with femtosecond laser-assisted cataract surgery(FLACS).This is the first report of both procedures combined simultaneously,with or without history of LTK.Case Description:A 68-year-old male presented with a history of LTK with two enhancements each eye in 2004,with subsequent surgically induced high corneal astigmatism,and with age-related nuclear cataract of both eyes.IOL master demonstrated+7.71 diopters of astigmatism at 163 degree right eye and+3.29 diopters of astigmatism at 4 degree left eye.After extensive discussion of the risks and benefits,the patient agreed to undergo FLACS with FSAK with two 61 degrees of relaxation incisions(RIs)and toric IOL(Alcon SN6AT9)right eye;FLACS with toric IOL(Alcon SN6AT7)alone left eye.At 2-year follow-up,uncorrected visual acuity was 20/30 right eye,20/25 left eye.His best corrected visual acuity was 20/25(+0.25+1.00 axis 21)right eye and 20/20(plano+0.25 axis 90)left eye;his best corrected near visual acuity was J1+with add+2.50 diopters right eye and left eye.Conclusions:Patients with age-related cataract and LTK induced high corneal astigmatism can hardly be sufficiently treated with FSAK or toric IOL alone at the time of cataract surgery.An effective way is to combine large FSAK and toric IOL of the highest cylindrical power of T9,in our case,simultaneously,which can achieve an excellent long term visual outcome. 展开更多
关键词 high corneal astigmatism[induced by laser thermal keratoplasty(LTK)] femtosecond laser astigmatic keratotomy(FSAK) toric intraocular lens implantation(IOL implantation) femtosecond laser-assisted cataract surgery(FLACS) case report
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Heterogeneous geological conditions and differential enrichment of medium and high maturity continental shale oil in China
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作者 HU Suyun BAI Bin +10 位作者 TAO Shizhen BIAN Congsheng ZHANG Tianshu CHEN Yanyan LIANG Xiaowei WANG Lan ZHU Rukai JIA Jinhua PAN Zhejun LI Siyang LIU Yuxi 《Petroleum Exploration and Development》 CSCD 2022年第2期257-271,共15页
Based on the comparison of basic geological conditions and enrichment characteristics of shale oil plays, the heterogeneity of source and reservoir conditions and differential enrichment of medium-high maturity contin... Based on the comparison of basic geological conditions and enrichment characteristics of shale oil plays, the heterogeneity of source and reservoir conditions and differential enrichment of medium-high maturity continental shale oil plays in China have been confirmed.(1) Compared with the homogeneous geological settings and wide distribution of marine shale oil strata in North America, the continental medium and high maturity shale oil plays in China are significantly different in geological conditions generally;continental multi-cyclic tectonic evolution forms multiple types of lake basins in multi-stages, providing sites for large-scale development of continental shale oil, and giving rise to large scale high-quality source rocks, multiple types of reservoirs, and diverse source-reservoir combinations with significant heterogeneity.(2) The differences in sedimentary water environments lead to the heterogeneity in lithology, lithofacies, and organic material types of source rocks;the differences in material source supply and sedimentary facies belt result in reservoirs of different lithologies, including argillaceous and transition rocks, and tight siltstone, and complex source-reservoir combination types.(3) The heterogeneity of the source rock controls the differentiation of hydrocarbon generation and expulsion, the diverse reservoir types make reservoir performance different and the source-reservoir configurations complex, and these two factors ultimately make the shale oil enrichment patterns different. Among them, the hydrocarbon generation and expulsion capacity of high-quality source rocks affect the degree of shale oil enrichment. Freshwater hydrocarbon source rocks with TOC larger than 2.5% and saline hydrocarbon source rocks with TOC of 2% to 10% have a high content of retained hydrocarbons and are favorable.(4) High-abundance organic shale is the basis for the enrichment of shale oil inside the source. In addition to being retained in shale, liquid hydrocarbons migrate along laminae, diagenetic fractures, and thin sandy layers, and then accumulate in laminae of argillaceous siltstone, siltstone, and argillaceous dolomite, and dolomitic siltstone suites, etc. with low organic matter abundance in the shale strata, resulting in differences in enrichment pattern. 展开更多
关键词 continental shale oil medium to high maturity geological characteristics heterogeneity enrichment pattern Junggar Basin Songliao Basin Ordos Basin Santanghu Basin
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Effect of TICL implantation on corneal astigmatism and the stability and visual quality after operation
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作者 Zi-Jing Wu Wan-Jiang Dong +5 位作者 Long Chen Zhong Luo Su-Ying Yu Miao He Juan Wu Xian-Ming Lei 《Journal of Hainan Medical University》 2020年第23期22-26,共5页
Objective:To explore the effect of TICL implantation on corneal astigmatism,postoperative stability and visual quality.Methods:110 patients(174 eyes)with high myopia and astigmatism who were treated with TICL implanta... Objective:To explore the effect of TICL implantation on corneal astigmatism,postoperative stability and visual quality.Methods:110 patients(174 eyes)with high myopia and astigmatism who were treated with TICL implantation in our hospital from July 2016 to July 2018 were selected as the research subjects.The follow-up time was 12 months.The changes of UCVA,BCVA,and astigmatism values were used as indicators to evaluate the effectiveness of treatment.The diopter changes of the affected eye at different periods after surgery and the changes in the rotation angle of the intraocular lens axis at different periods after surgery were used as indicators to determine the stability of surgical treatment.Results:The UCVA and BCVA of the affected eyes after operation were significantly higher than those before operation(P<0.05).Compared with pre-operation,the diopter of the affected eyes was significantly reduced after operation(P<0.05);Based on the axial position of the intraocular lens on the first day after surgery,the degree of rotation of the intraocular lens implanted in the affected eyes was significantly reduced(P<0.05);Compared with pre-operation,there was no statistically significant difference in corneal endothelial cell count,intraocular pressure,and arch height after operation.Conclusion:Patients with high myopia and corneal astigmatism received TICL implantation after correction treatment,visual acuity was significantly improved,visual quality was significantly improved,with good postoperative stability,which had good clinical promotion value. 展开更多
关键词 high myopia Corneal astigmatism TICL implantation
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Comparison between toric and spherical phakic intraocular lenses combined with astigmatic keratotomy for high myopic astigmatism 被引量:4
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作者 Lin-Yan Zheng Shuang-Qian Zhu +3 位作者 Yan-Feng Su Hu-Yong Zou Qin-Mei Wang A-Yong Yu 《Eye and Vision》 SCIE 2017年第1期114-120,共7页
Background:To compare the outcomes of a toric phakic intraocular lens(PIOL)and a spherical PIOL combined with astigmatic keratotomy(AK)for the correction of high myopic astigmatism.Methods:This study enrolled patients... Background:To compare the outcomes of a toric phakic intraocular lens(PIOL)and a spherical PIOL combined with astigmatic keratotomy(AK)for the correction of high myopic astigmatism.Methods:This study enrolled patients with high myopic astigmatism,including 30 eyes(22 patients)that received a toric PIOL implantation(TICL group),and 32 eyes(24 patients)that received combined AK and a spherical PIOL implantation(AK+ICL group).The outcomes were compared between the two groups before surgery,and at the following time points after surgery:1 week,1,3,6 months,and 1,2 years.Results:Preoperatively,the mean manifest spherical equivalent(SE)was−14.14±2.12 D in the TICL group and−14.83±2.79 D in the AK+ICL group(P=0.28),and the mean manifest refractive cylinder,−2.87±1.09 D and−2.58±0.85 D,respectively(P=0.28).Two years postoperatively,the mean safety index was 1.53±0.55 in the TICL group and 1.60±0.70 in the AK+ICL group(P=1.00),and the mean efficacy index,1.18±0.45 and 1.38±0.52,respectively(P=0.86).The mean manifest refractive cylinder correction was 1.94±1.07 D in the TICL group and 1.39±0.71 D in the AK+ICL group(P=0.02).The mean changes in SE and refractive cylinder from 1 week to 2 years were less than 0.50 D in both groups.Conclusions:Both TICL implantation and AK+ICL implantation are a good alternative for correction of astigmatism in addition to high myopia.TICL implantation has better predictability in correction of high myopic astigmatism. 展开更多
关键词 astigmatism high myopia Phakic intraocular lenses Astigmatic keratotomy
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Heat treatment and granule medium internal highpressure forming of AA6061 tube 被引量:3
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作者 毕江 赵长财 +3 位作者 毕蒙蒙 杜冰 陈晓华 董国疆 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1040-1049,共10页
The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the form... The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the forming requirement, and the granule medium internal high pressure forming method for AA6061 alloy tube was also realized by using convenient implementation with low requirement of equipment and flexible design of product. At a solution temperature of 560℃ and time of 120 min, the elongation of the AA6061 extruded tube increases by 300% and the strength and the hardness dramatically decrease too. Therefore, the AA6061 alloy tube meets the requirement of internal high-pressure forming because of the improvement of formability. The experiments shows that the strength and hardness of AA6061 alloy workpiece recover to that of the as-received alloy at an aging temperature of 180℃ and time of 360 min, and the strength of AA6061 alloy workpiece is equal to the base alloy. The typical parts of convex ring tube, stepped shaft tube and hexagonal tube were successfully produced in lab by using the present forming method. The forming tests show that the maximum expansion ratio(MER) of the AA6061 extruded tube increases by 25.5% and the material properties of formed AA6061 alloy tube reached the performance of as-received alloy. 展开更多
关键词 aluminum alloy TUBE solution TREATMENT aging TREATMENT GRANULE medium INTERNAL high pressure FORMING
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Effects of Combined Instantaneous High-Pressure and Medium Temperature on Peroxidase Activity in Wax Gourd Juices 被引量:1
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作者 CHEN Cong gui, WANG Wu, ZHANG Li, FANG Hong mei and HE Jing min (School of Biology and Food Engineering, Hefei University of Technology, Hefei 230061, P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2003年第9期1030-1034,共5页
Based on the instantaneous pressurization and depressurization produced by high pressure single pole cylinder pump and valve, the effects of the continuous processing on the peroxidase (POD) activity in wax gourd ju... Based on the instantaneous pressurization and depressurization produced by high pressure single pole cylinder pump and valve, the effects of the continuous processing on the peroxidase (POD) activity in wax gourd juices were investigated. Results showed that the processing factors such as pressure, temperature, pH and processing time are important to the POD activity. POD in crude juices could be inactivated apparently above 50 MPa(pH 4.6, 35℃, 4 min), and activated at 20 MPa ( P < 0.01). Its remarkable inactivation could also be observed at 45 and 55℃ (20 MPa, pH 4.6, 4 min), and the evident activation appears at the material temperature 35℃ ( P < 0.01). The pH 3.0 could destroy POD almost completely (20 MPa, 35℃, 4 min), while pH 6.0 could not influence apparently the POD activity in crude juices( P > 0.05). In addition, the rules of POD activity along with the treatment time are variational under different processing pressures. The higher the treating pressure is, the shorter the processing time is needed to inactivate POD. 展开更多
关键词 Instantaneous high pressure medium temperature Combined process POD ACTIVITY
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Effects of Combined Instantaneous High-Pressure and MediumTemperature on the Retention of Total Vitamin Cin Wax Gourd Juices 被引量:2
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作者 LIUJin-jie WANGWu +2 位作者 ZHANGLi HEJing-min CHENCong-gui 《Agricultural Sciences in China》 CAS CSCD 2003年第8期919-923,共5页
Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juic... Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juices were investigated under 20 - 80 MPa, 35 - 58℃, pH 3. 0 - 6. 0 and processing time 0-8 min. Results showed that the loss of Vc increased with elevated processing temperatures(50 MPa, 4 min). When the temperature of raw juices was 35℃, the retention of total Vc was higher under 40 - 60 MPa than that under the pressure < 40 MPa or > 60 MPa, and it was up to 94%(4 min). The retention of total Vc decreases slowly within 6 min, but rapidly after 6 min. The pH can also influence the retention of total Vc, and this retention can come to a highest point at pH 6.0. 展开更多
关键词 Instantaneous high-pressure medium temperature Combined process Vitamin C RETENTION
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Effect of RE-Modifier on Microstructure and Mechanical Property of High-Carbon Medium-Manganese Steel 被引量:1
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作者 SONG Yan-pei XIE Jing-pei +1 位作者 ZHU Yao-min WANG Ai-qin 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2002年第1期36-39,共4页
The effect of RE-modifier on the microstructure and mechanical properties of high carbon-medium manganese steel has been investigated in present work.The results showed that the RE-modifier can refine the crystalline ... The effect of RE-modifier on the microstructure and mechanical properties of high carbon-medium manganese steel has been investigated in present work.The results showed that the RE-modifier can refine the crystalline grain of high-carbon medium-manganese steel.The shape and distribution of carbides are improved and the columnar grains and phosphide in grain boundary are eliminated.Consequently,the impact toughness of the steel is increased by more than one time,compared with no addition of RE-modifier. 展开更多
关键词 RE-modifier high-carbon medium-manganese steel microstructure and property
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Robust Synchronization in an E/I Network with Medium Synaptic Delay and High Level of Heterogeneity
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作者 韩芳 王直杰 +1 位作者 范宏 龚涛 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期25-28,共4页
It is known that both excitatory and inhibitory neuronal networks can achieve robust synchronization only under certain conditions, such as long synaptic delay or low level of heterogeneity. In this work, robust synch... It is known that both excitatory and inhibitory neuronal networks can achieve robust synchronization only under certain conditions, such as long synaptic delay or low level of heterogeneity. In this work, robust synchronization can be found in an excitatory/inhibitory (E/I) neuronal network with medium synaptie delay and high level of heterogeneity, which often occurs in real neuronal networks. Two effects of post-synaptic potentials (PSP) to network synchronization are presented, and the synaptic contribution of excitatory and inhibitory neurons to robust synchronization in this E/I network is investigated. It is found that both excitatory and inhibitory neurons may contribute to robust synchronization in E/I networks, especially the excitatory PSP has a more positive effect on synchronization in E/I networks than that in excitatory networks. This may explain the strong robustness of synchronization in Eli neuronal networks. 展开更多
关键词 PSP Robust Synchronization in an E/I Network with medium Synaptic Delay and high Level of Heterogeneity
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The Research and Analysis to the Financing Dilemma and Countermeasures of China's Medium and Small Sized High-tech Enterprises
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作者 Wang Zhi 《International English Education Research》 2014年第8期36-38,共3页
关键词 高新技术企业 融资问题 中国 法人治理结构 法律法规 信用担保 参考价值 无声音
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Vacuum Infusion Molding Process Part 1:VIMP Based on a High-Permeable Medium 被引量:1
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作者 祝颖丹 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第3期72-75,共4页
The visualization experiments were carried out to investigate the permeability of the high permeable medium (HPM) and the roles of the peel ply and the HPM in the mold filling.The influence of process parameters on m... The visualization experiments were carried out to investigate the permeability of the high permeable medium (HPM) and the roles of the peel ply and the HPM in the mold filling.The influence of process parameters on mold filling is discussed.Furthermore,the whole vacuum infusion molding process (VIMP) procedure is introduced in detail taking the manufacture of a model boat for example. 展开更多
关键词 vacuum infusion molding process high permeable medium PERMEABILITY mold filling
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Development of a Medium Voltage, High Power, High Frequency Four-Port Solid State Transformer 被引量:1
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作者 Ahmad El Shafei Saban Ozdemir +2 位作者 Necmi Altin Garry Jean-Pierre Adel Nasiri 《CES Transactions on Electrical Machines and Systems》 CSCD 2022年第1期95-104,共10页
The power and voltage levels of renewable energy resources is growing with the evolution of the power electronics and switching module technologies.For that,the need for the development of a compact and highly efficie... The power and voltage levels of renewable energy resources is growing with the evolution of the power electronics and switching module technologies.For that,the need for the development of a compact and highly efficient solid-state transformer is becoming a critical task in-order to integrate the current AC grid with the new renewable energy systems.The objective of this paper is to present the design,implementation,and testing of a compact multi-port solid-state transformer for microgrid integration applications.The proposed system has a four-port transformer and four converters connected to the ports.The transformer has four windings integrated on a single common core.Thus,it can integrate different renewable energy resources and energy storage systems.Each port has a rated power of 25 kW,and the switching frequency is pushed to 50 k Hz.The ports are chosen to represent a realistic industrial microgrid model consisting of grid,energy storage system,photovoltaic system,and load.The grid port is designed to operate at 4.16 k VAC corresponding to 7.2 kV DC bus voltage,while the other three ports operate at 500 VDC.Moreover,the grid,energy storage and photovoltaic ports are active ports with dual active bridge topologies,while the load port is a passive port with full bridge rectifier one.The proposed design is first validated with simulation results,and then the proposed transformer is implemented and tested.Experimental results show that the designed system is suitable for 4.16 k VAC medium voltage grid integration. 展开更多
关键词 CO-SIMULATION high frequency high power medium voltage MICROGRID MULTI-PORT solid state transformer
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Medium Optimization for Improved Ethanol Production in Very High Gravity Fermentation 被引量:6
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作者 胡纯铿 秦晴 高培培 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期1017-1022,共6页
最佳的媒介(300 g 螆铧 ? 髧 ?? 颼賥??? 旤??
关键词 培养基优化 发酵生产 乙醇发酵 重力 ATP酶活性 ATPASE活性 酵母提取物 发酵时间
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Effect of Boron on Delayed Fracture Resistance of Medium-Carbon High Strength Spring Steel 被引量:2
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作者 NIE Yi-hong HUI Wei-jun +1 位作者 FU Wan-tang WENG Yu-qing 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2007年第6期53-57,67,共6页
The delayed fracture behavior of medium carbon high strength spring steel containing different amounts of boron (0. 000 5%, 0. 001 6 %) was studied using sustained load delayed fracture test. The results show that d... The delayed fracture behavior of medium carbon high strength spring steel containing different amounts of boron (0. 000 5%, 0. 001 6 %) was studied using sustained load delayed fracture test. The results show that delayed fracture resistance of boron containing steels is higher than that of conventional steel 60Si2MnA at the same strength level and it increases with the increase of boron eontent from 0. 000 5% to 0. 001 6%. The delayed fracture mode is mainly intergranular in the boron containing steels tempered at 350℃, which indicates that the addition of boron does not change the fracture character. However, the increase of boron content enlarges the size of the crack initia tion area. Further study of phase analysis indicates that most boron is in solid solution, and only a very small quantity of boron is in the M3 (C, B) phase. 展开更多
关键词 borons delayed fracture resistances medium-carbon high strength spring steel
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High Performance Liquid Chromatography Separation and Simultaneous Fluorometric Detection of Trace Amount of Polyamines in Ce
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作者 王淳本 雷景迈 +1 位作者 柴锡禄 何善述 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1995年第2期125-128,共4页
A highly sensitive and precise method for the determination of the polyamines (including putrescine, spermidine and spermine) in cell culture media is described. The samples were concentrated by C18 column and the pol... A highly sensitive and precise method for the determination of the polyamines (including putrescine, spermidine and spermine) in cell culture media is described. The samples were concentrated by C18 column and the polyamines were converted to fluorometric derivatives with DNS-Cl. The polyamine derivatives were then completely separated by HPLC and determined by simultaneous fluorometric detection. The CV of intragroup and intergroup were 2. 49 %-4. 26% and 4. 29 %-5. 16 %, respectively. The rate of recovery was 103%- 99%. There was trace amount of polyamines detected by this method in the media of F12, 8900, RPMI1640, DMEM and M199 even without incubation with cells. So this method can be used for detecting the changes of polyamines in a medium before and after incubation with cells. It is helpful for the researches on the regulation of cell proliferation by polyamines. 展开更多
关键词 medium PUTRESCINE SPERMIDINE SPERMINE high performance liquid chromatography fluorospectrophotometry
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Mold Filling Analysis in Vacuum Infusion Molding Process Based on a High-Permeable Medium 被引量:2
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作者 Yingdan ZHU, Hua TAN and Jihui WANGState Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第5期467-471,共5页
The objective of this paper is to understand the flow mechanism through visualization experiments and discuss theinfluence of process parameters on mold filling process. A 2D leakage flow model is developed to simulat... The objective of this paper is to understand the flow mechanism through visualization experiments and discuss theinfluence of process parameters on mold filling process. A 2D leakage flow model is developed to simulate the moldingprocess, and the simulation results show good agreement with experiments. 展开更多
关键词 Vacuum infusion molding process (VIMP) high-permeable medium Mold filling SIMULATION
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ANALYSES OF ERRORS IN MEDIUM-TERM NUMERICAL FORECAST PRODUCTS FOR THE SUBTROPICAL HIGH 1998 被引量:1
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作者 王兴荣 姚叶青 +3 位作者 尚瑜 陈晓平 程小泉 率爱梅 《Journal of Tropical Meteorology》 SCIE 2003年第1期105-112,共8页
By statistic and dynamic analyses, we have come to the following conclusions: (1) The ECMWF medium-term numerical forecast can forecast medium-term activity of subtropical high, and the accuracy rate of forecast canno... By statistic and dynamic analyses, we have come to the following conclusions: (1) The ECMWF medium-term numerical forecast can forecast medium-term activity of subtropical high, and the accuracy rate of forecast cannot have large improvement by translational corrections. (2) The important cause for the ECMWF medium-term numerical forecast to have errors in 1998 is that the astronomical tide is not included in the model. (3) Two indexes are found from which it can be judged that ECMWF medium-term numerical forecast will have errors if the astronomical tide is ignored in the model : ① When the 54.7?line under the moon of the nodical month astronomical singularities coincides with the trough-line of the subtropical jet flow from 50癊 to 150癊 on the 500 hPa level at 2000 L.T. of the same day, and is approximately vertical (α>60? with the isotherm, then the day 0 2 days after the appearance of the nodical month astronomical singularities is defined as the initial day. Then in three successive days after the initial day, ECMWF medium-term numerical forecast of the northern latitude of the 588 line at 120 癊 will have continuous errors as large as two latitudes (7/9). Otherwise, it won’t have continuous errors (13/13). ② Otherwise, if the 54.7 ?line is in the range of a low pressure between two high pressures, then there is a dispersive error on the day of the nodical month astronomical singularities (5/7). There is not any error (6/6) otherwise. 展开更多
关键词 中期数值预报 天气预报 副热带高压 误差分析 大气动力学分析 大气潮汐
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Microstructural Transformation and Precipitation of an Ultra-high Strength Steel under Continuous Cooling
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作者 陈永利 ZHAO Yang +1 位作者 ZHOU Xuejiao HUANG Jianguo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第2期387-392,共6页
We investigated phase transition and precipitation of ultra-high strength steel(UHSS)in a new "short process" with controlled rolling and controlled cooling.Thermalexpansion test combined with metallographic obser... We investigated phase transition and precipitation of ultra-high strength steel(UHSS)in a new "short process" with controlled rolling and controlled cooling.Thermalexpansion test combined with metallographic observation was used to research the continuous cooling transformation(CCT)curve.Moreover,the microstructuraltransformation and precipitation law was revealed by morphologicalobservation and alloying elements by electron probe micro-analyzer(EPMA).Transmission electron microscopy(TEM)was utilized to analyze the composition and grain orientation of microstructure.The study showed that the measured criticaltransformation temperatures of Ac1 and Ac3 were 746 and 868 ℃,respectively.The CCT curve indicated that the undercooled austenite was transformed into proeutectoid ferrite and bainite with HV 520 in a broad range of cooling rate 0.1^(-1) ℃·s^(-1).When subjected to a cooling rate of 1 ℃·s^(-1),the undercooled austenite was divided into small-sized blocks by formed martensite.With further increase of cooling rate,micro-hardness increased dramatically,the microstructure of specimen was mainly lathe bainite(LB),granular bainite(GB),lath martensite(LM)and residualaustenite.By diffraction test analysis,it was identified that there was K-S orientation relationship between martensite and austenite for {110}_α//{111}_γ,{111}_α//{101}_γ.EPMA clearly showed that carbon diffused adequately due to staying for a long time at high temperature with a lower cooling rate of 2 ℃·s-1.Phase transition drive force was lower and the residualaustenite existed in the block form of Martensite austenite island(M-A).With the increase of cooling rate to 10 ℃·s^(-1),the block residualaustenite reduced,the carbon content of residualaustenite increased and α phase around the residualaustenite formed into a low carbon bainite form. 展开更多
关键词 ultra high strength steel continuous cooling transformation medium plate bainite martensite residual austenite
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Polymorphism analyses of HLAB-15 group in Chinese with medium to high resolution method
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《中国输血杂志》 CAS CSCD 2001年第S1期366-,共1页
关键词 high Polymorphism analyses of HLAB-15 group in Chinese with medium to high resolution method
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