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Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury 被引量:1
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作者 Mou Gao Qin Dong +4 位作者 Zhijun Yang Dan Zou Yajuan Han Zhanfeng Chen Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期872-880,共9页
Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regen... Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury. 展开更多
关键词 closed head injury Ctbp2 induced neural stem cell lncRNA H19 miR-325-3p NEUROGENESIS
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THE SUPPORTED GOLD CATALYSTS FOR CLOSED CYCLE CO_2 LASER
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作者 Zheng Ping HAO Li Dun AN Hong Li WANG (Lanxhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第5期447-448,共2页
Sealed-off carbon dioxide lasers encounter problem of dissociation of CO2, Which causes the output power to fall. Reformation of CO2 is therefore essential for long life CO2 lasers. Au/Fe2O3 and Au/NiFe2O4 are promis... Sealed-off carbon dioxide lasers encounter problem of dissociation of CO2, Which causes the output power to fall. Reformation of CO2 is therefore essential for long life CO2 lasers. Au/Fe2O3 and Au/NiFe2O4 are promising candidates for this application. 展开更多
关键词 CO THE SUPPORTED GOLD CATALYSTS FOR closed cycle CO2 LASER
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Modelling and development of recycled water conditioning of copper-molybdenum ores processing 被引量:1
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作者 Irina Pestriak Valery Morozov Erdenetuya Otchir 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第2期313-317,共5页
Current use of enrichment and processing technologies of ores requires the introduction of closed circuits of water treatment. A decrease in technological properties is caused by accumulations of ion-molecular compone... Current use of enrichment and processing technologies of ores requires the introduction of closed circuits of water treatment. A decrease in technological properties is caused by accumulations of ion-molecular components in the circulating water. The objective of the simulation is to determine the maximum allowable concentrations of ions and molecules as well as the choice of conditions for deposition or adsorption.First of all, our examinations decrease the concentration of copper ions and fatty acids in the circulating water. By pre-mixing water with the highest concentration of these ions, a reduction of copper ion and fatty acid concentrations in the recycled water occurs. The results do not only ensure the achievement of the maximum permitted concentration(MPC) of copper and iron, significantly reducing the amount of oxidized copper, they also make it possible to use the united sewage as current water for the flotation process. Mixing and adding filtrate of tailings, discharges of urban wastewater treatment and effluent of ash pit of thermal power stations(TPS) to recycled water causes an increase in the capacity of the enrichment plant by 15–17%. 展开更多
关键词 TAILINGS recycling WATER closed cycle Urban waste WATER CONDITIONING FLOTATION of ORE Natural WATER
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EFFECT OF DYNAMIC STRAIN AGING ON LOW CYCLE FATIGUE BEHAVIOUR OF 18-8 AUSTENITIC STAINLESS STEEL 被引量:2
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作者 PENG Kaiping CHEN Wenzhe OIAN Kuangwu Fuzhou University,Fuzhou,China teaching assistant,Department of Mechanical Engineering,Fuzhou University,Fuzhou 350002,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1993年第6期420-425,共6页
Studies were made of the symmetric tensile-compressive low cycle fatigue behaviour and the influence of dynamic strain aging(DSA)pre-treatment of 18-8 austenitic stainless steel. Within the testing amplitude range of ... Studies were made of the symmetric tensile-compressive low cycle fatigue behaviour and the influence of dynamic strain aging(DSA)pre-treatment of 18-8 austenitic stainless steel. Within the testing amplitude range of strain.±0.5 % to±1.5 %,the three processes of cyclic hardening,cyclic saturation and cyclic softening were observed.In the same amplitude of strain,the peak stress of the samples pre-treated by DSA is higher than that of solid-solu- tion and cold working pre-treatment,but no remarkable differences of the fatigue lives of them were found.TEM observation shows that the uniform and stable dislocation networks with high density form after DSA pre-treatment,which increases the cyclic peak stress.The cyclic softening results from the low dislocation density and elongated cell structure with low energy. 展开更多
关键词 18-8 austenitic stainless steel dynamic strain aging low cycle fatigue
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Biological function of miRNA-145-5p in angiotensin II induced renal inflammation
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作者 BIN LI YUCHENG SHENG +7 位作者 XIAOYING XU SHENGCUN WANG HONGYAN SONG JINGYUAN LI HAONAN JI QINGHUA WANG XIAODI ZHOU LONGJU QI 《BIOCELL》 SCIE 2024年第4期601-611,共11页
Objective:Chronic kidney disease(CKD)is a progressive disorder characterized by intricate structural and functional alterations in the kidneys,attributable to diverse causative factors.Notably,the therapeutic promise ... Objective:Chronic kidney disease(CKD)is a progressive disorder characterized by intricate structural and functional alterations in the kidneys,attributable to diverse causative factors.Notably,the therapeutic promise of miR-145-5p in addressing renal pathologies has been discerned.This investigation seeks to elucidate the functional role of miR-145-5p in injured kidneys by subjecting human glomerular mesangial cells(HGMCs)to stimulation with Angiotensin II(AngII).Materials and Methods:Cellular viability and the levels of inflammatory mediators were evaluated utilizing Cell Counting Kit-8(CCK-8),quantitative real-time polymerase chain reaction(qRT-PCR),and western blot methodologies,both in the presence of AngII incubation and in scenarios of miR-145p overexpression and downregulation.Furthermore,the cell cycle dynamics were elucidated through Fluorescence-activated Cell Sorting(FACS)analysis.Results:AngII incubation induced an upregulation of miR-145-5p and inflammatory factors including Intercellular Adhesion Molecule 1(ICAM-1),Interleukin 6(IL-6),Interleukin 8(IL-8),and Interleukin 1β(IL-1β).Additionally,it elevated the expression of Cyclin A2,Cyclin D1,and the G2/M cell cycle ratio.Conversely,inhibition of miR-145-5p heightened the levels of inflammatory factors and cell cycle regulators induced by AngII incubation.Reduced expression of miR-145-5p correlated with a downregulation of Interleukin 10(IL-10)expression,concurrently promoting HGMC proliferation under AngII stimulation.Moreover,ectopic miR-145-5p expression demonstrated a reduction in inflammatory factors,cell cyclin regulators,G2/M cell cycle ratio,and overall proliferation.Conclusion:MiR-145-5p exhibited inhibitory effects on the inflammatory response and proliferation induced by Angiotensin II in HGMCs,showcasing its potential as a therapeutic avenue for the treatment of kidney injury. 展开更多
关键词 miR-145-5p KIDNEY Angiotensin II Cell cycle INFLAMMATION
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Multiple cycles of magnetic activity in the Sun and Sun-like stars and their evolution
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作者 Elena Aleksandrovna Bruevich Vasily Vladimirovich Bruevich Boris Pavlovich Artamonov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第7期21-36,共16页
The wavelet transform method for high-quality time-frequency analysis is applied to sets of observations of relative sunspot numbers and stellar chromosphere fluxes of 10 Sun-like stars. Wavelet analysis of solar data... The wavelet transform method for high-quality time-frequency analysis is applied to sets of observations of relative sunspot numbers and stellar chromosphere fluxes of 10 Sun-like stars. Wavelet analysis of solar data shows that in a certain interval of time there are several cycles of activity with pe- riods of duration which vary considerably from each other: from quasi-biennial cycles to lO0-yr cycles. Cyclic activity was detected in almost all Sun-like stars that we examined, even those that previously were not considered as stars with cyclic activity according to analysis using a Scargle periodogram. The durations of solar and stellar cycles significantly change during the observation period. 展开更多
关键词 SUN activity - multiple cycles - Sun-like stars ACTIVITY
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Net Present Value Method: A Method Recommended by ISO 15686-5 for Economic Evaluation of Building Life Cycle Costs
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作者 Hao Xie Qiao Cui Yang Li 《World Journal of Engineering and Technology》 2022年第2期224-229,共6页
The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This stu... The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method. 展开更多
关键词 NPV ISO 15686-5 BUILDING Life cycle Cost Economic Evaluation
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The Experimental and Clinical Study on the Effect of Curcumin on Cell Cycle Proteins and Regulating Proteins of Apoptosis in Acute Myelogenous Leukemia 被引量:2
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作者 陈燕 吴裕丹 +1 位作者 何静 陈文娟 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第4期295-298,共4页
To investigate whether the Bcl- 2 gene family is involved in m odulating mechanism of apoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL - 6 0 cell line and primary acute m y... To investigate whether the Bcl- 2 gene family is involved in m odulating mechanism of apoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL - 6 0 cell line and primary acute m yelogenous leukem ic cells,the Bcl- 2 family member Mcl- 1,Bax and Bak and cell cycle proteins including P2 7kipl,P2 1wafl,cyclin D3and p Rbp- were selected and their ex- pression detected by SABC imm uno- histochem ical stain m ethod.The attitude of sub- G1 peak in DNA histogram was determined by FCM.The TU NEL positive cell percentage was identified by term inal deoxynucleotidyl transferase (Td T ) - m ediated Biotin d U NP end labeling technique.It was found that when HL - 6 0 cells were treated with 2 5μm ol/ L curcumin for 2 4 h,the expression level of Mcl- 1was down- regulated,but that of Bax and Bak up- regulated time- dependently.There was significant difference in the expression level of Mcl- 1,Bax and Bak between the curcumin- treated groups and control group(P<0 .0 5 - 0 .0 1) .At the sam e time,curcumin had no effect on progress of cell cycle in prim aty acute m yelogenous leukemia at newly diagnosis,but could in- crease the peak of Sub- G1 (P<0 .0 5 ) ,and down- regulate the expression of Mcl- 1and up- regulate the expression of Bax and Bak with the difference being statistically significant.The expression of P2 7kipl,P2 1wafl and p Rbp- were elevated and thatof cyclin D3decreased in the presence of curcum in. These findings suggested thatthe Bcl- 2 gene fam ily indeed participated in the regulatory process of apoptosis induced by curcumin in HL - 6 0 cells and AML cells.Curcumin can induce apoptosis of primary acute myelogenous leukemic cells and disturb cell cycle progression of HL - 6 0 cells.The m echanism appeared to be m ediated by perturbing G0 / G1 phases checkpoints which associated with up- regulation of P2 7kipl,P2 1wafl and p Rbp- expression,and down- regulation of cyclin D3. 展开更多
关键词 curcum in Bcl- 2 gene family cell cycle protein HL - 6 0 cell prim ary leukemic cell
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Can Asymmetry of Solar Activity be Extended into Extended Cycle? 被引量:1
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作者 Ke-JunLi Jing-XiuWang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2002年第1期66-70,共5页
With the use of the Royal Greenwich Observatory data set of sunspot groups, an attempt is made to examine the north-south asymmetry of solar activity in the 'extended' solar cycles. It is inferred that the asy... With the use of the Royal Greenwich Observatory data set of sunspot groups, an attempt is made to examine the north-south asymmetry of solar activity in the 'extended' solar cycles. It is inferred that the asymmetry established for individual solar cycles does not extend to the 'extended' cycles. 展开更多
关键词 Sun: sunspot - Sun: active cycle - Sun: activity
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Molecular Engineering Design for High-Performance Aqueous Zinc-Organic Battery 被引量:5
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作者 Tianjiang Sun Weijia Zhang +1 位作者 Qingshun Nian Zhanliang Tao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第3期98-111,共14页
Novel small sulfur heterocyclic quinones(6a,16adihydrobenzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,7,9,14,16,18-hexaone(4S6Q)and benzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,9,14,18-t... Novel small sulfur heterocyclic quinones(6a,16adihydrobenzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,7,9,14,16,18-hexaone(4S6Q)and benzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,9,14,18-tetraone(4S4Q))are developed by molecule structural design method and as cathode for aqueous zincorganic batteries.The conjugated thioether(–S–)bonds as connected units not only improve the conductivity of compounds but also inhibit their dissolution by both extendedπ-conjugated plane and constructed flexible molecular skeleton.Hence,the Zn//4S6Q and Zn//4S4Q batteries exhibit satisfactory electrochemical performance based on 3.5 mol L-1(M)Zn(ClO4)2electrolyte.For instance,the Zn//4S6Q battery obtains 240 and 208.6 mAh g^(-1)of discharge capacity at 150 mA g^(-1)and 30 A g^(-1),respectively.The excellent rate capability is ascribed to the fast reaction kinetics.This system displays a superlong life of 20,000 cycles with no capacity fading at 3 A g^(-1).Additionally,the H+-storage mechanism of the 4S6Q compound is demonstrated by ex situ analyses and density functional theory calculations.Impressively,the battery can normally work at-60℃benefiting from the anti-freezing electrolyte and maintain a high discharge capacity of 201.7 mAh g^(-1),which is 86.2%of discharge capacity at 25℃.The cutting-edge electrochemical performances of these novel compounds make them alternative electrode materials for Zn-organic batteries. 展开更多
关键词 Aqueous Zn-organic battery Small sulfur heterocyclic quinones Conjugated thioether skeleton Superlong cycling life H+-involved mechanism -60℃
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基于多级压缩回热过程的半闭式S-CO_(2)循环回热优化研究
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作者 孙恩慧 纪洪福 +3 位作者 石嘉豪 张磊 徐进良 李永毅 《中国电机工程学报》 EI CSCD 北大核心 2023年第17期6755-6764,共10页
在单回热半闭式超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))循环中,CO_(2)在不同温度和压力下的比热容差异较大,导致回热器两侧工质的温度匹配性较差,不可逆损失较大。构建多级压缩回热过程是改善单回热循环回热性能的有效... 在单回热半闭式超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))循环中,CO_(2)在不同温度和压力下的比热容差异较大,导致回热器两侧工质的温度匹配性较差,不可逆损失较大。构建多级压缩回热过程是改善单回热循环回热性能的有效方法。该文在单回热循环的基础上,通过添加分流再压缩过程,提出再压缩半闭式S-CO_(2)循环,并获得6.63%的效率提升,同时从数学公式中证明效率提高的原因是叠加了净功。进一步构建三压缩循环时,发现回热器两侧工质流量的不匹配使得回热器内部出现温度交叉,体现出半闭式S-CO_(2)循环存在多种质量流耦合匹配问题,可通过对燃料、氧气和回流CO_(2)在回热器中进行流量匹配来解决。结果表明,三压缩循环相比再压缩循环的效率可进一步提高1.47%。通过构建多级压缩回热过程,充分挖掘了半闭式S-CO_(2)循环的效率潜力,可获得较好的性能。 展开更多
关键词 半闭式S-CO_(2)循环 多级压缩回热 循环效率 回热优化 多流匹配
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Bang-Bang型电推进氙贮供系统两相流仿真研究与开闭周期优化
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作者 高俊 孙臻琦 +4 位作者 陈阳 陈涛 贾泽正 王伟宗 罗颢文 《推进技术》 EI CAS CSCD 北大核心 2023年第7期49-58,共10页
针对某Bang-Bang型电推进氙贮供系统,基于Amesim仿真平台搭建起流动、传热动态数值模型进行两相流仿真研究,采用MBWR状态方程准确揭示氙工质相态变化。仿真模型与试验数据对比验证后,对Bang-Bang阀开闭周期进行参数敏感性分析来优化系... 针对某Bang-Bang型电推进氙贮供系统,基于Amesim仿真平台搭建起流动、传热动态数值模型进行两相流仿真研究,采用MBWR状态方程准确揭示氙工质相态变化。仿真模型与试验数据对比验证后,对Bang-Bang阀开闭周期进行参数敏感性分析来优化系统设计。结果表明:系统各工作阶段Bang-Bang阀下游缓冲罐压强以及各极流量仿真结果与试验数据或额定值误差在1.76%以内。Bang-Bang阀在异步工作周期中,中间小气容由于焦汤效应而温度瞬间下降,氙工质由气态转变为两相态并持续0.315s。采用适中的开闭周期可以在缩短缓冲罐建压响应时间的同时实现Bang-Bang阀的长寿命使用。 展开更多
关键词 电推进 氙贮供系统 Bang-Bang阀 两相流仿真 开闭周期
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The Expression of Cyclooxygenase-2 in Cervical Cancers and Hela Cells Was Regulated by Estrogen/Progestogen
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作者 李允光 濮德敏 李艳丽 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第4期457-460,共4页
To investigate the relationship between the expression of cyclooxygenase-2 (COX-2) and menstrual cycle, the regulatory effects of 17-β-estradiol (E2) and medroxyprogesterone acetate (MPA) on the expression of C... To investigate the relationship between the expression of cyclooxygenase-2 (COX-2) and menstrual cycle, the regulatory effects of 17-β-estradiol (E2) and medroxyprogesterone acetate (MPA) on the expression of COX-2 in cervical cancer Hela cells were examined. Cervical cancer specimens were obtained from 47 pre-menopausal patients. The phase of menstrual cycle was determined by case history and HE staining of uterine endometrium. COX-2 was immunohistochemically stained by SABC staining and the staining intensity was determined with computerized image analysis system. Hela cells were incubated with alcohol, E2, E2+MPA, MPA for 12, 24 and 48 h respectively. The expression of COX-2 in Hela cells was detected by Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Our results showed that the expression of COX-2 was significantly higher during proliferative phase than secretory phase (P〈0.05), but there was no difference in the positive rate between proliferative phase and secretory phase (P〉0.05). Incubation with E2 could significantly enhance the expression of COX-2 continually. On the contrary, E2+MPA and MPA alone could decrease the expression of COX-2 as compared with the control and E2 group (P〈0.05 and P〈0.01 respectively). It is concluded that the expression of COX-2 in cervical cancer of pre-menopausal patients and Hela cells was regulated by estrogen/progestogen. 展开更多
关键词 cervical cancer cyclOOXYGENASE-2 menstrual cycle 17-Β-ESTRADIOL medroxyprogesterone acetate
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基于占空比波表的三相四线整流器控制
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作者 肖义平 田垚 王超 《电力电子技术》 2024年第1期1-5,共5页
三相脉宽调制(PWM)整流器应用广泛。针对三相四线(TPFW)PWM整流器,提出了一种基于占空比波表的电压电流双闭环控制策略。该控制策略电压外环采用波表系数步进调节控制,电流内环采用离散比例积分微分(PID)控制叠加电容电压步进调节均衡... 三相脉宽调制(PWM)整流器应用广泛。针对三相四线(TPFW)PWM整流器,提出了一种基于占空比波表的电压电流双闭环控制策略。该控制策略电压外环采用波表系数步进调节控制,电流内环采用离散比例积分微分(PID)控制叠加电容电压步进调节均衡控制。该方法能够提高系统功率因数,同时也能抑制整流器输出直流侧电压波动以及实现电容电压均衡。最后在硬件平台上进行实验验证,实验结果表明该控制策略具有抑制输出电压纹波、功率因数高、系统稳定性好等优点。与传统方法相比,该控制方法控制简单,易于工程实践. 展开更多
关键词 整流器 占空比波表 双闭环控制策略 步进调节
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Dynamic simulation of a space gas-cooled reactor power system with a closed Brayton cycle 被引量:2
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作者 Chenglong WANG Ran ZHANG +4 位作者 Kailun GUO Dalin ZHANG Wenxi TIAN Suizheng QIU Guanghui SU 《Frontiers in Energy》 SCIE CSCD 2021年第4期916-929,共14页
Space nuclear reactor power(SNRP)using a gas-cooled reactor(GCR)and a closed Brayton cycle(CBC)is the ideal choice for future high-power space missions.To investigate the safety characteristics and develop the control... Space nuclear reactor power(SNRP)using a gas-cooled reactor(GCR)and a closed Brayton cycle(CBC)is the ideal choice for future high-power space missions.To investigate the safety characteristics and develop the control strategies for gas-cooled SNRP,transient models for GCR,energy conversion unit,pipes,heat exchangers,pump and heat pipe radiator are established and a system analysis code is developed in this paper.Then,analyses of several operation conditions are performed using this code.In full-power steady-state operation,the core hot spot of 1293 K occurs near the upper part of the core.If 0.4$reactivity is introduced into the core,the maximum temperature that the fuel can reach is 2059 K,which is 914 K lower than the fuel melting point.The system finally has the ability to achieve a new steady-state with a higher reactor power.When the GCR is shut down in an emergency,the residual heat of the reactor can be removed through the conduction of the core and radiation heat transfer.The results indicate that the designed GCR is inherently safe owing to its negative reactivity feedback and passive decay heat removal.This paper may provide valuable references for safety design and analysis of the gas-cooled SNRP coupled with CBC. 展开更多
关键词 gas-cooled space nuclear reactor power closed Brayton cycle system startup and shutdown positive reactivity insertion accident
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基于过程拆分的半闭式超临界CO_(2)循环热力学分析及流程优化
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作者 于良 辛团团 +1 位作者 张逸飞 许诚 《动力工程学报》 CAS CSCD 北大核心 2024年第6期991-1000,共10页
面对日益紧迫的减碳降耗需求,发展高效低碳的先进热力循环愈发重要。提出了一种基于天然气的零碳排放的半闭式超临界CO_(2)循环,并通过工质拆分,将半闭式循环拆解为开式循环和闭式循环,以阐明循环热功转化的过程;进一步采用循环拆分法... 面对日益紧迫的减碳降耗需求,发展高效低碳的先进热力循环愈发重要。提出了一种基于天然气的零碳排放的半闭式超临界CO_(2)循环,并通过工质拆分,将半闭式循环拆解为开式循环和闭式循环,以阐明循环热功转化的过程;进一步采用循环拆分法将复杂重构循环拆解为若干简单循环,建立不同流程重构措施的热力学评价模型,直观地揭示不同循环构型的节能机理;通过参数敏感性分析获得各个流程改良措施关键参数的最优点。结果表明:再热、分流再压缩、中间冷却、部分冷却等多种循环流程改良措施均可有效提高循环效率,其效率增益为1.79~5.59个百分点;多种流程改良措施集成优化后,系统净发电效率较基础循环提高10.18个百分点。 展开更多
关键词 超临界CO_(2)循环 碳捕集 循环拆分法 半闭式循环
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玻璃纤维滤材的疏水改性及过滤性能
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作者 陈欣 俞杰 +8 位作者 李永国 李昕 林中鑫 裴鉴禄 郑芹 刘涛 张昭辰 刘经国 张继荣 《材料工程》 EI CAS CSCD 北大核心 2024年第4期200-208,共9页
闭式循环过程会产生大量放射性气溶胶,其高湿、高酸、高放射性的特点导致基于玻璃纤维滤材的高效过滤器失效快、更换频率高。为解决上述问题,提出对传统的玻璃纤维滤材进行疏水性改性,以提高玻璃纤维滤材对苛刻工况的耐受性。利用低表... 闭式循环过程会产生大量放射性气溶胶,其高湿、高酸、高放射性的特点导致基于玻璃纤维滤材的高效过滤器失效快、更换频率高。为解决上述问题,提出对传统的玻璃纤维滤材进行疏水性改性,以提高玻璃纤维滤材对苛刻工况的耐受性。利用低表面能改性剂(聚二甲基硅氧烷)对滤材进行化学性疏水性改性,通过引用SiO_(2)纳米颗粒物进行微结构构造,进一步改善疏水效果。借助SEM、FTIR、接触角测量仪等手段对改性效果进行了分析,并进一步研究了改性滤材的过滤性能。研究结果表明:改性方案能够有效改善玻璃纤维滤材的疏水性,并提高其耐湿性;单纯化学改性滤材的静态接触角可达146°,引入SiO_(2)纳米颗粒物后改性滤材的接触角超过150°;当改性剂中聚二甲基硅氧烷质量分数为2.0%、SiO_(2)纳米颗粒物质量分数为0.5%时,所得GF-PS-0.5滤材展现出最优的耐酸性,主要源于化学性疏水和结构性疏水的有效协同;GF-PS-0.5在经受足量的γ照射后,疏水性保持稳定,表明其良好的耐辐照性;改性滤材仍然保持了优异的过滤性能,其过滤效率超过99.99%。改性过程在提高滤材耐受性的同时,没有影响其过滤性能,展现出良好的应用前景。 展开更多
关键词 闭式循环 玻璃纤维滤材 疏水改性 耐酸性 耐辐照性
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植物黄体素(Lutein)与环氧化黄体素-黄体素循环 被引量:9
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作者 林植芳 彭长连 林桂珠 《植物生理学通讯》 CAS CSCD 北大核心 2006年第3期385-394,共10页
介绍黄体素的生物合成途径,其在光合膜中的定位、生理功能及调控因子,提高黄体素水平的基因工程研究与生产应用概况以及近年来对新发现的环氧化黄体素-黄体素循环在植物中的分布、运行动态与功能的初步研究进展,并提出尚需深入研究的问题。
关键词 黄体素(lutein) 环氧化黄体素-黄体素循环(lutein epoxide—lutein cycle) 生物合成途径 生理功能
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一类被开发的捕食-食饵系统的定性分析 被引量:5
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作者 韦煜明 曾琬婷 丁昌明 《广西师范大学学报(自然科学版)》 CAS 北大核心 2006年第3期30-33,共4页
讨论了一类食饵种群被开发的两种群捕食系统,主要讨论了系统平衡点的行为以及系统的全局稳定性。用P ioncare切性曲线法及Du lac函数法得到了闭轨不存在的充分条件。用Hop f分支理论及张芷芬唯一性定理证明了极限环的存在唯一性。
关键词 捕食系统 极限环 闭轨 HOPF分支 平衡点
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15kW等级闭式海洋温差KSC-11发电系统的性能分析 被引量:2
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作者 高铁瑜 龚建英 钱继扬 《太阳能学报》 EI CAS CSCD 北大核心 2012年第2期343-348,共6页
对15kW等级混合工质海洋温差卡林纳-11循环(简称KSC-11)系统进行计算和分析。结果表明,对于给定的透平进口压力,KSC-11系统存在相对应的最佳氨质量分数。对于给定氨质量分数的KSC-11系统,也存在相对应的最佳透平进口压力。在可利用海水... 对15kW等级混合工质海洋温差卡林纳-11循环(简称KSC-11)系统进行计算和分析。结果表明,对于给定的透平进口压力,KSC-11系统存在相对应的最佳氨质量分数。对于给定氨质量分数的KSC-11系统,也存在相对应的最佳透平进口压力。在可利用海水温差19℃条件下,15kW等级KSC-11系统中,氨质量分数对最大净功影响不大,对应最佳透平进口压力为0.60~0.75MPa;氨质量分数为0.95的KSC-11系统综合性能最好,单位净功产量的换热器总面积γ为6~7m2/kW,对应的最佳透平进口压力为0.75MPa。 展开更多
关键词 海洋温差发电 闭式循环 卡林纳-11循环 氨工质
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