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Numerical Study on the Pulsation Characteristics of An Attached Air Bubble Under A Nearby Oscillating Bubble
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作者 JIANG Ming-zuo LIU Kun +1 位作者 WANG Jia-xia WEN Xiao-hu 《China Ocean Engineering》 SCIE EI CSCD 2023年第2期299-311,共13页
Numerical simulations of the non-spherical evolution of a pulsating bubble interacting with a stationary air bubble attached to a fixed structure were performed using a three-dimensional boundary integral method by im... Numerical simulations of the non-spherical evolution of a pulsating bubble interacting with a stationary air bubble attached to a fixed structure were performed using a three-dimensional boundary integral method by implementing the mirror image method to simplify the processing of the numerical model. Code validation was accomplished by comparing the numerical results with the laboratory experimental data obtained in our previous study. Complex phenomena were observed, including three types of bubble jet forms, which depended strongly on the distance parameter with respect to the initial location of the bubble from the plate, the bubble strength parameter and the initial air bubble radius parameters. The results of the simulations provide detail insight into interesting bubble jetting phenomena,such as bubble splitting, jets moving away from the plate, and bubble shedding. The dimensionless distance parameter and the initial air bubble radius parameter play a major role in determining the shapes of two bubbles and the jetting direction. The air bubble strength parameter did not change the bubble jet direction but influenced the bubble shape.The detachment of the attached air bubble under oscillating bubble suction was easily observed for a small initial air bubble. These results showed that bubble jetting toward the plate was manipulated through the effect of attached air bubble, and that cavitation-based applications and underwater explosion bubble may benefit from this erosion mitigation approach. 展开更多
关键词 bubble dynamics attached air bubble bubble collapse liquid jet
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Universal Encapsulation Adhesive for Lead Sedimentation and Attachable Perovskite Solar Cells with Enhanced Performance
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作者 Xuehao Zhu Haoyu Cai +7 位作者 Cong Bai Zhengzhe Wu Wenjian Shen Yiming Xiong Juan Zhao Fuzhi Huang Yibing Cheng Jie Zhong 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期303-310,共8页
In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-h... In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-heal within 45 min at room temperature with an efficient lead ion-blocking rate of 99.3%.The PUA film can be coated on a metal electrode with slight efficiency improvement from 23.96%to 24.15%.The thermal stability at 65℃and the humidity stability at 55%relative humidity(RH)are superior to the devices encapsulated with polyisobutylene.The PUA film has strong adhesion to the flexible substrate and the initial efficiency of the flexible perovskite module(17.2%)encapsulated by PUA remains 92.6%within 1825 h.These results suggest that PUA encapsulation is universal for rigid and flexible PSCs with enhanced stability and low lead hazards.Moreover,it was found that flexible PSCs can be well attached to various substrates with PUA,providing a facile route for the A-PSCs in various scenarios without additional encapsulation and installation. 展开更多
关键词 ADHESIVE attachable device flexible module lead leakage POLYURETHANE
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Attachment Styles and Traumatic Responses: Exploring the Impact of Parental Interaction on Child Development and Coping Mechanisms
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作者 Kelvin N. Christie Adalgiza Sandoval 《Open Journal of Psychiatry》 2024年第S1期467-489,共23页
This article explores the intricate relationship between attachment styles formed during early childhood and the subsequent responses to traumatic events, particularly the death of a parent. Drawing on the theoretical... This article explores the intricate relationship between attachment styles formed during early childhood and the subsequent responses to traumatic events, particularly the death of a parent. Drawing on the theoretical framework of attachment theory and incorporating contemporary research, the paper discusses how parental interactions shape the neural circuitry of infants and children, influencing their ability to form secure or insecure attachments. These attachment styles, in turn, play a critical role in determining the child’s coping mechanisms when faced with trauma. This paper focuses on trying to understand how attachment theory is connected to the reaction to trauma with a highlight on the four major styles of attachments which are secure, anxious, avoidant, and disorganized to mention but a few, and how they influence stress and adversity in children. Attachment theory holds that human beings’ ability to form affectional bonds in infancy determines their patterns of relatedness across the life cycle. The type of attachment that is secure usually supports healthy adaptation and good coping mechanisms regardless of the trauma in the childhood of the child. While secure attachment mostly facilitates favorable trauma-related outcomes, anxious or avoidant attachment can exacerbate or alter the responses. The caregiving system that is avoidant attachment has implications of autonomous self-functioning which has features of suppression of the emotional response and poor search for emotional support during stress. From the principles of developmental psychology and trauma theory, the paper also focuses on the major significance of the child’s early caregivers’ interactions that define the resilience and vulnerability factor. This knowledge is therefore critical in designing specific interventions based on the improvement of coping behaviors and emotional regulatory systems of children who have been exposed to trauma. Finally, we have the synthesis of new knowledge about the role of secure attachment relationships as its fundamental element in shaping adaptive traumatization and psychological development. The article also delves into the physiological processes involved in emotional regulation and the role of cortisol in disrupting attachment. Finally, the implications of these findings for therapeutic interventions and the challenges of addressing prolonged grief and traumatic responses in clinical settings are considered. 展开更多
关键词 attachment Styles Traumatic Response Parental Interaction Child Development Emotional Regulation CORTISOL Grief Coping NEUROBIOLOGY Therapeutic Interventions
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Mechanism of Tourists’Happiness in Traditional Village Tourism: A Perspective Grounded in Nostalgia and Cultural Attachment
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作者 JIANG Juan LIU Yu 《Journal of Landscape Research》 2024年第4期73-79,共7页
In recent years,traditional villages have emerged as popular tourist destinations due to their distinctive resource value.Typically situated in remote and less developed areas,traditional villages boast primitive natu... In recent years,traditional villages have emerged as popular tourist destinations due to their distinctive resource value.Typically situated in remote and less developed areas,traditional villages boast primitive natural surroundings and rich historical and cultural heritage.These characteristics offer urban dwellers a temporary escape from the complexities of modern life,allowing them to experience physical and mental rejuvenation,mental relaxation,and overall happiness during their visit.By conducting a review of the existing literature concerning tourists’happiness in traditional villages,this study establishes a framework to understand tourists’happiness in traditional village tourism.Using the Qiangang ancient village in Conghua District,Guangzhou as a case study,the research examines the current state of rural characteristics,the establishment of cultural brands,and the promotion of the active utilization of ancient villages within the context of integrating culture,sports,tourism,and agriculture.Based on this analysis,the author proposes strategies to enhance tourists’happiness,including the preservation and development of rural characteristics,the promotion and preservation of local cultural attributes,and the collaborative advancement of culture,sports,tourism,and agriculture to engage key stakeholders actively. 展开更多
关键词 Traditional village Qiangang ancient village NOSTALGIA Cultural attachment HAPPINESS
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广义逆多项式模的Attached素理想
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作者 欧阳伦群 刘金旺 《数学物理学报(A辑)》 CSCD 北大核心 2014年第3期521-529,共9页
设R是有单位元1的结合环,(S,≤)是严格全序Artin幺半群,M_R是右R-模,Att(M_R)与Att([M^(S,≤)]_([[R^(S,≤)]]))分别表示模M_R与广义逆多项式模[M^(S,≤)]_([[R^(S,≤)]])的所有Attached素理想组成的集合.该文主要讨论了广义幂级数环[[R... 设R是有单位元1的结合环,(S,≤)是严格全序Artin幺半群,M_R是右R-模,Att(M_R)与Att([M^(S,≤)]_([[R^(S,≤)]]))分别表示模M_R与广义逆多项式模[M^(S,≤)]_([[R^(S,≤)]])的所有Attached素理想组成的集合.该文主要讨论了广义幂级数环[[R^(S;≤)]]广义逆多项式模[[R^(S;≤)]]的Attached素理想的相关性质,证明了在一定条件下,有Att([M^(S,≤)]_([[R^(S,≤)]])={[[PR^(S;≤)]]P∈Att(M_R)}.这一结论表明广义逆多项式模([M^(S,≤)]_([[R^(S,≤)]])的Attached素理想在一定条件下可以用模M_R的Attached素理想来刻画,推广了Annin S在文献[1]中关于斜多项式环上逆多项式模的Attached素理想的相关结论. 展开更多
关键词 attached素理想 广义幂级数环 广义逆多项式模
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Cell-attached膜片上,咖啡因对猪冠状动脉平滑肌细胞K_(Ca)的调节作用 被引量:1
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作者 仲维高 曾晓荣 +6 位作者 杨艳 刘智飞 李妙龄 张维维 蔡芳 裴杰 周文 《四川生理科学杂志》 2007年第2期53-56,共4页
目的:研究咖啡因对猪冠状动脉平滑肌细胞KCa通道的调控机理,以期揭示胞内钙库RyR激活后,局部钙离子浓度升高和KCa的关系。方法:采用急性酶分离方法,应用膜片钳单通道电流记录技术记录大脑皮层神经元猪冠状动脉平滑肌细胞上KCa通道电流... 目的:研究咖啡因对猪冠状动脉平滑肌细胞KCa通道的调控机理,以期揭示胞内钙库RyR激活后,局部钙离子浓度升高和KCa的关系。方法:采用急性酶分离方法,应用膜片钳单通道电流记录技术记录大脑皮层神经元猪冠状动脉平滑肌细胞上KCa通道电流活动。电流信号经放大、滤波及A/D、D/A转换后输入微机进行采样和储存。实验数据应用CLAMP9.0软件系统进行数据采集及分析。结果:在cell-attached膜片上咖啡因对KCa通道有明显的作用,咖啡(0.1-5.0 mM)可以增加通道的开放概率(NPo),呈现出浓度依赖性,开放时间延长,关闭时间也随之缩短,而对电流幅值无明显影响,开放概率的增加是通过明显缩短平均关闭时间实现的(n=8,P<0.05);洗去药物后通道活性可以一定程度的恢复到对照水平,再加入一定浓度咖啡因(如1.0mM)可再次激活KCa,激活程度与洗脱前较接近。结论:在细胞贴附式构型上咖啡因浓度依赖性地激活KCa,有饱和性。可能是通过影响胞内信号转导过程而调控KCa活性。 展开更多
关键词 咖啡因 BKCA 猪冠状动脉平滑肌细胞 离子通道 膜片钳技术
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Community structure and controlled factor of attached green algae on the Porphyra yezoensis aquaculture rafts in the Subei Shoal, China 被引量:6
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作者 LI Yan XIAO Jie +6 位作者 DING Lanping WANG Zongling SONG Wei FANG Song FAN Shiliang LI Ruixiang ZHANG Xuelei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期93-99,共7页
This study analyzes the community structure, the quantity changes of the algae and the effect of important environmental factors and estimates the total biomass of the attached green algae in the survey areas. The stu... This study analyzes the community structure, the quantity changes of the algae and the effect of important environmental factors and estimates the total biomass of the attached green algae in the survey areas. The study uses data from surveys of the attached green algae on the Porphyra yezoensis aquaculture rafts and data regarding the environmental factors from October 2010 to April 2011 in the Subei Shoal. The attached green algae on the rafts included Ulva prolifera, Capsosiphon groenlandicus, U. linza, U. intestinalis, U. clathrata, and U. cornpressa. The biomass changes of the attached green algae exhibited an inverted parabola: the biomass was the highest (14 898 t) in April, and was the second highest (2 034 t) in November; it was lowest in February (only 729 t) and increased sharply from March to April. The species diversity differed significantly among the seasons. In September and October, when the P. yezoensis aquaculture rafts were initially set up, the attached green algae had a high biodiversity, while from December to the next February, a variety of green algae species coexisted on the rafts, although the biomass was low, and from March to April, as the biomass increased sharply, the species diversity dropped to the minimum. During this time, C. groenlandicus was apparently dominant with the maximum biomass proportion up to 80%, while the U. prolifera proportion increased exponentially to 20% to 40%. The water temperature had a direct regulating effect on the biomass and the species succession of the attached green algae. The estimation of the community dynamics and the biomass of the green algae provided the evidence needed to track the origin of the large-scale green tide in the southern Yellow Sea. 展开更多
关键词 Porphyra yezoensis aquaculture attached green algae community structure controlled factor SubeiShoal
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Particle size distribution and property of bacteria attached to carbon fines in drinking water treatment 被引量:4
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作者 Wang Leilei Chen Wei Lin Tao 《Water Science and Engineering》 EI CAS 2008年第2期102-111,共10页
The quantitative change and size distribution of particles in the effluents from a sand filter and a granular activated carbon (GAC) filter in a drinking water treatment plant were investigated. The average total co... The quantitative change and size distribution of particles in the effluents from a sand filter and a granular activated carbon (GAC) filter in a drinking water treatment plant were investigated. The average total concentration of particles in the sand filter effluent during a filter cycle was 148 particles/mL, 27 of which were larger than 2 μm in size. The concentration in the GAC effluent (561 particles/mL) was significantly greater than that in the sand filter effluent. The concentration of particles larger than 2 μm in the GAC filter effluent reached 201 particles/mL, with the amount of particles with sizes between 2 μm and 15 μm increasing. The most probable number (MPN) of carbon fines reached 43 unit/L after six hours and fines between 0.45 μm and 8.0 μm accounted for more than 50%. The total concentration of outflowing bacteria in the GAC filter effluent, 350 CFU (colony-forming units) /mL, was greater than that in the sand filter effluent, 210 CFU/mL. The desorbed bacteria concentration reached an average of 310 CFU/mg fines. The disinfection efficiency of desorbed bacteria was lower than 40% with 1.5 mg/L of chlorine. The disinfection effect showed that the inactivation rate with 2.0 mg/L of chloramine (90%) was higher than that with chlorine (70%). Experimental results indicated that the high particle concentration in raw water and sedimentation effluent led to high levels of outflowing particles in the sand filter effluent. The activated carbon fines in the effluent accounted for a small proportion of the total particle amount, but the existing bacteria attached to carbon fines may influence the drinking water safety. The disinfection efficiency of desorbed bacteria was lower than that of free bacteria with chlorine, and the disinfection effect on bacteria attached to carbon fines with chloramine was better than that with only chlorine. 展开更多
关键词 drinking water treatment particles size distribution bacteria attached to carbon fines INACTIVATION
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The contribution of attached Ulva prolifera on Pyropia aquaculture rafts to green tides in the Yellow Sea 被引量:4
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作者 Hongbin Han Shiliang Fan +5 位作者 Wei Song Yan Li Jie Xiao Zongling Wang Xuelei Zhang Dewen Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第2期101-106,共6页
Green tides caused by the unusual accumulation of high floating Ulva prolifera have occurred regularly in the Yellow Sea since 2007.The primary source of the Yellow Sea green tides is the attached algae on the Pyropia... Green tides caused by the unusual accumulation of high floating Ulva prolifera have occurred regularly in the Yellow Sea since 2007.The primary source of the Yellow Sea green tides is the attached algae on the Pyropia aquaculture rafts in the Subei Shoal.Ulva prolifera and Blidingia(Italic)sp.are the main species observed on Pyropia aquaculture rafts in the Subei Shoal.We found that U.prolifera has strong buoyancy and a rapid growth rate,which may explain why it is the dominant species of green tides that occur in the China's sea area of the Yellow Sea.The growth rate of floating U.prolifera was about 20%–31%d–1,which was much higher than Blidingia(Italic)sp.There were about 1.7×104 t of attached algae on the Pyropia aquaculture rafts in May 2012.We found that 39%of attached algae could float when the tide rose in the Subei Shoal,and U.prolifera accounted for 63%of the floating algae.Our analysis estimated that about 4000 t of attached U.prolifera floated into the surrounding waters of the Subei Shoal during the recycling period of aquaculture rafts.These results suggest that the initial floating biomass of large-scale green tides in the Yellow Sea is determined by the U.prolifera biomass attached to Pyropia aquaculture rafts,further impacting the scale of the green tide。 展开更多
关键词 attached algae Pyropia aquaculture rafts Blidingia(Italic)sp. Ulva prolifera green tides
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Determination of optimal blowing-to-suction flow ratio in mechanized excavation face with wall-mounted swirling ventilation using numerical simulations 被引量:5
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作者 Runze Gao Pengfei Wang +1 位作者 Yongjun Li Ronghua Liu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第2期248-264,共17页
Wall-mounted swirling ventilation is a new type of system in mechanized excavation faces with a dust sup-pression performance that is closely related to the blowing-to-suction flow ratio.Physical and simulation models... Wall-mounted swirling ventilation is a new type of system in mechanized excavation faces with a dust sup-pression performance that is closely related to the blowing-to-suction flow ratio.Physical and simulation models were developed according to the No.C103 mechanized excavation face in the Nahe Coal Mine of the Baise Mining Bureau,Guangxi Province to optimize the blowing-to-suction flow ratio for wall-mounted swirling ventilation.Both the k-εturbulence model and the discrete phase model were utilized to simulate airflow field structures and dust concentration distribution patterns at various blowing-to-suction flow ratios.The results suggest that higher blowing-to-suction flow ratios increase the airflow field disturbance around the working face and weaken the intensity of the axial air curtain.On the other hand,both the intensity of the radial air curtain and the dust suppression effect are enhanced.At a blowing-to-suction flow ratio of 0.8,the wall-mounted swirling ventilation system achieved the most favorable dust suppression performance.Both the total dust and respirable dust had their lowest concentrations with maximum efficiencies of reducing both types at 90.33%and 87.16%,respectively. 展开更多
关键词 Mechanized excavation face wall-mounted swirling ventilation Blowing-to-suction flow ratio Airflow field DUST
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HUSTserver:Implementation for Reliable and High-Performance Network Attached Storage System 被引量:2
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作者 郭辉 周敬利 余胜生 《Journal of Shanghai University(English Edition)》 CAS 2003年第2期156-162,共7页
Network attached storage (NAS) with the properties of improved scalability, simplified management, low cost and balanced price performance, is desirable for high performance storage systems applied to extensive area... Network attached storage (NAS) with the properties of improved scalability, simplified management, low cost and balanced price performance, is desirable for high performance storage systems applied to extensive areas. Unfortunately, it also has some disadvantages such as increased network workload, and inconvenience in disaster recovery. To overcome these disadvantages, we propose a channel bonding technique and provide hot backup functions in the designed NAS system, named HUSTserver. Channel bonding means merging multiple Ethernet channels into integrated one, and that the data packets can be transferred through any available network channels in a parallel mode. The hot backup function provides automatic data mirroring among servers. In this paper, we first describe the whole system prototype from a software and hardware architecture view. Then, multiple Ethernet and hot backup technologies that distinguish HUSTserver from others are discussed in detail. The findings presented demonstrate that network bandwidth can be scaled by the use of multiple commodity networks. Dual parallel channels of commodity 100 Mbps Ethernet are both necessary and sufficient to support the data rates of multiple concurrent file transfers. And the hot backup function introduced in our system provides high data accessibility. 展开更多
关键词 storage systems network attached storage computer network channel bonding data mirroring.
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Studies on the Attached Cultivation of Filamentous Oleaginous Microalga Tribonema minus 被引量:3
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作者 ZHANG Yan JI Chunli +3 位作者 ZHOU Wenjun WANG Hui WANG Junfeng LIU Tianzhong 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第3期691-699,共9页
Attached cultivation is a promising method for microalgal biomass production. Filamentous oleaginous microalga Tribonema minus(hereafter T. minus) has shown a remarkable potential for biofuel production in terms of it... Attached cultivation is a promising method for microalgal biomass production. Filamentous oleaginous microalga Tribonema minus(hereafter T. minus) has shown a remarkable potential for biofuel production in terms of its high lipid content. However, the strain has only been cultivated in suspended cultivation systems including open pond and closed photobioreactors. Here, we attempted to study the attached cultivation of T. minus, which might be helpful for its scale-up cultivation and industrial applications. As the results, the optimal conditions for T. minus growth in the attached biofilm are 200 μmol photons m^-2 s^-1 of light intensity and 5% of CO2, and the maximum biomass density of 223 g m^-2 has been achieved under the light intensity. The non-woven fabric as substratum was found as the best substratum in thin layer attached bioreactor, on which the average biomass productivity of T. minus is about(9.73 ± 2.19) g m^-2)d^-1. Furthermore, two attached bioreactor systems, rotary drum and rotation disc, were designed following the light dilution strategy and introduced into T. minus cultivation. The highest footprint areal biomass productivity of these two systems is 33 and 47.1 g m^-2 d^-1, respectively, much higher than that in suspended cultivation system. The results shows that T. minus can be cultured with attached cultivation method to improve its biomass productivity. 展开更多
关键词 Tribonema minus attached culture biomass productivity light dilution
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Role of mental health professionals in dealing with the stigma attached to COVID-19 被引量:2
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作者 Shobhit Kumar Prasad Aarti Karahda +1 位作者 Priti Singh Rajiv Gupta 《General Psychiatry》 CSCD 2020年第5期363-365,共3页
The stigma associated with the disease may be as subtle as avoidance,or dramatic as physical aggression.COVID-19 has begun to cause social disruption by growing disease-related stigma and xenophobia against some cultu... The stigma associated with the disease may be as subtle as avoidance,or dramatic as physical aggression.COVID-19 has begun to cause social disruption by growing disease-related stigma and xenophobia against some cultural,national,racial or religious groups worldwide.1 People of East Asian origin and those with facial features like them,or those with a travel history to areas affected by the outbreak,are especially being subjected to xenophobia in personal contact and online threats.COVID-19 has arisen as an unknown and newly emerged highly contagious infection that has spread rapidly across the globe and is associated with high mortality,leading to fear of encountering those infected.2 Leaders across the world have taken strict measures such as lockdowns and shutdown of various vital services that have caused chaos in people’s lives and increased concerns about the disease.3 Box 1 lists the factors leading to stigmatisation towards those infected with COVID-19. 展开更多
关键词 attached dealing RELIGIOUS
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Cyclin B1 is localized to unattached kinetochores and contributes to efficient microtubule attachment and proper chromosome alignment during mitosis 被引量:3
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作者 Chen,Q Zhang,X +2 位作者 Jiang,Q Clarke,PR Zhang,C 《Cell Research》 SCIE CAS CSCD 2008年第2期268-280,共13页
Cyclin B1 is a key regulatory protein controlling cell cycle progression in vertebrates. Cyclin B1 binds CDK1, a cy-clin-dependent kinase catalytic subunit, forming a complex that orchestrates mitosis through phosphor... Cyclin B1 is a key regulatory protein controlling cell cycle progression in vertebrates. Cyclin B1 binds CDK1, a cy-clin-dependent kinase catalytic subunit, forming a complex that orchestrates mitosis through phosphorylation of key proteins. Cyclin B1 regulates both the activation of CDK1 and its subcellular localization, which may be critical for substrate selection. Here, we demonstrate that cyclin B1 is concentrated on the outer plate of the kinetochore during prometaphase. This localization requires the cyclin box region of the protein. Cyclin B1 is displaced from individual kinetochores to the spindle poles by microtubule attachment to the kinetochores, and this displacement is dependent on the dynein/dynactin complex. Depletion of cyclin B1 by vector-based siRNA causes inefficient attachment between kinetochores and microtubules, and chromosome alignment defects, and delays the onset of anaphase. We conclude that cyclin B1 accumulates at kinetochores during prometaphase, where it contributes to the correct attachment of mi- crotubules to kinetochores and efficient alignment of the chromosomes, most likely through localized phosphorylation of specific substrates by cyclin B1-CDK1. Cyclin B1 is then transported from each kinetochore as microtubule attachment is completed, and this relocalization may redirect the activity of cyclin B1-CDK1 and contribute to inactivation of the spindle assembly checkpoint. 展开更多
关键词 cyclin B1 KINETOCHORE DYNEIN chromosome alignment microtubule attachment
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Effects of forced aeration on community dynamics of free and attached bacteria in copper sulphide ore bioleaching 被引量:4
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作者 Wei Chen Shenghua Yin I.M.S.K.Ilankoon 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第1期59-69,共11页
Bacterial community dynamics and copper leaching with applied forced aeration were investigated during low-grade copper sulphide bioleaching to obtain better bioleaching efficiency.Results illustrated that appropriate... Bacterial community dynamics and copper leaching with applied forced aeration were investigated during low-grade copper sulphide bioleaching to obtain better bioleaching efficiency.Results illustrated that appropriate aeration improved bacterial concentrations and leaching efficiencies.The highest bacterial concentration and Cu^(2+)concentration after 14-d leaching were 7.61×10^(7) cells·mL^(−1) and 704.9 mg·L^(−1),respectively,at aeration duration of 4 h·d^(−1).The attached bacteria played a significant role during bioleaching from 1 to 7 d.However,free bacteria dominated the bioleaching processes from 8 to 14 d.This phenomenon was mainly caused by the formation of passivation layer through Fe3+hydrolysis along with bioleaching,which inhibited the contact between the attached bacteria and ore.Meanwhile,16S rDNA analysis verified the effect of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans on the bioleaching process.The results demonstrate the importance of free and attached bacteria in bioleaching. 展开更多
关键词 attached bacteria BIOLEACHING forced aeration free bacteria low-grade copper sulphide ore
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Dynamic analysis of elastic screen surface with multiple attached substructures and experimental validation 被引量:2
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作者 王宏 刘初升 +2 位作者 彭利平 蒋小伟 冀连权 《Journal of Central South University》 SCIE EI CAS 2012年第10期2910-2917,共8页
A feasible method to improve the reliability and processing efficiency of large vibrating screen via the application of an elastic screen surface with multiple attached substructures (ESSMAS) was proposed. In the ES... A feasible method to improve the reliability and processing efficiency of large vibrating screen via the application of an elastic screen surface with multiple attached substructures (ESSMAS) was proposed. In the ESSMAS, every screen rod, with ends embedded into elastomer, is coupled to the main screen structure in a relatively flexible manner. The theoretical analysis was conducted, which consists of establishing dynamic model promoted from the fuzzy structure theory as well as calculating for the equivalent stiffness of each attached structure. According to the numerical simulation using the NEWMARK-fl integration method, this assembling pattern significantly leads to the screen surface/rod having larger vibration intensity than that of the corresponding position on screen structure, which specifically, with an averaged acceleration amplitude increasing ratio of 11.37% in theoretical analysis and 20.27% in experimental test. The experimental results, within a tolerant error, also confirm the established model and demonstrate the feasibility of ESSMAS. 展开更多
关键词 mineral processing vibrating screen elastic screen surface attached substructures dynamic analysis reliability processing efficiency
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Effects of processing pH stimulation on cooperative bioleaching of chalcopyrite concentrate by free and attached cells 被引量:2
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作者 Tang-jian PENG Li-juan SHI +5 位作者 Run-lan YU Guo-hua GU Dan ZHOU Miao CHEN Guan-zhou QIU Wei-min ZENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第8期2220-2229,共10页
In order to investigate the effects of processing pH stimulation on bioleaching of chalcopyrite by moderate thermophiles,copper leaching rates and the dynamics of microbial community structures of free and attached ce... In order to investigate the effects of processing pH stimulation on bioleaching of chalcopyrite by moderate thermophiles,copper leaching rates and the dynamics of microbial community structures of free and attached cells were monitored. The results indicated that when the processing pH values were respectively adjusted to 1.0 and 3.0 on day 14, both free and attached cells experienced an adaptive phase. Meanwhile, the copper leaching rates were 86.9% and 64.0%,respectively, as opposed to a copper leaching rate of 87.5% in the control group without pH stimulation. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis suggested that pH stimulation imposed less impact on the attached organisms than on the free cells, indicating that the attached cells were more resistant to processing pH stimulation than the free cells. Furthermore, adjusting processing pH to 3.0 significantly disrupted both free and attached microbial communities, and the bioleaching system could not recover to the normal status as the control group. 展开更多
关键词 CHALCOPYRITE processing pH stimulation free cells attached cells microbial community real-time quantitative PCR
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Ultrafine Fraction and Aerosol Attached Activity Size Distribution of Radon Progeny in Living Room 被引量:2
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作者 Amer Mohamed Mohamed Moustafa lotfy Abd EI-Hady Mona Moustafa Mahmoud Mostafa Yuness Abd El Fatah 《Journal of Physical Science and Application》 2012年第7期205-215,共11页
Inhalation of 222Rn progeny in the domestic environment contributes the greatest fraction of the natural radiation exposure to the public. The ultrafine activity of these progeny amounts up to about l 0 percent of the... Inhalation of 222Rn progeny in the domestic environment contributes the greatest fraction of the natural radiation exposure to the public. The ultrafine activity of these progeny amounts up to about l 0 percent of the total activity (attached and ultrafine), but is considered to yield about 50 percent of the total radiation dose. Therefore, measurements of ultrafine fraction are essential for the estimation of radiation dose. The current study presents measured data on the total equilibrium equivalent concentration (EEC) and ultrafine equilibrium equivalent concentration (EECUn), ultrafine fraction (fb), attached and unattached activity size distributions of radon progeny in the low ventilated rooms at Minia University, Minia city, Egypt. A screen diffusion battery was used for collection the ultrafine fraction and measuring the total activity concentration of radon progeny. The attached activity size distribution of 214pb is determined by using a low pressure cascade impactor. The EEC of radon progeny varied between 1.3 and 18.9 Bq/m3 with a mean value of 5.2 ± 0.48 Bq/m2. The mean activity thermodynamic diameter (AMTD) ofultrafine of radon progeny was determined to be 1.26 nm with relative mean geometric standard deviations (GSD) of 1.3. The ultrafine fraction of radon progeny, fb, has a range 0.01 to 0.21 with an average of 0.08 ± 0.03. A relative mean GSD of 2.7 was determined for attached 2Lapb at a mean active median aerodynamic diameter (AMD) of 350 nm. Based on the above experimental results, the deposition fractions have been evaluated in each air way generation through the human lung by applying a lung deposition model. The bronchial deposition efficiencies of particles in the size range of attached radon progeny were found to be lower than those of ultrafine progeny. The effect of radon progeny deposition by adult male has been also studied for various levels of physical exertion. The dose conversion factor has been discussed as a function of fb. 展开更多
关键词 AEROSOL radon progeny activity size distribution ultrafine fraction and attached fraction.
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Construction of Crack Perturbation Model and Forward Semi-analytical Model of Attached Eddy Current Sensor
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作者 焦胜博 程礼 +2 位作者 李晓微 李培源 高君宇 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第3期279-288,共10页
Fatigue damage monitoring is critical metallic structure health monitoring of aircraft.The sensor should be high sensitive,easy to be integrated into structure and well adaptable for poor working conditions.Therefore,... Fatigue damage monitoring is critical metallic structure health monitoring of aircraft.The sensor should be high sensitive,easy to be integrated into structure and well adaptable for poor working conditions.Therefore,an attached eddy current sensor with flexible plane is put forward and its characteristics are analyzed.By extracting material′s conductivity as the crack features,forward semi-analytical model is established and parameter optimizations are carried out.Crack perturbation model of attached eddy current sensor is constructed,and perturbation voltages of sensing channels under three-dimension structural crack are obtained.To verify the sensor′s performance,monitoring experiment on crack extension is conducted under condition of 3 MHz frequency.The validation experimental results show that perturbation model of 2A12-T4 aluminum alloy agrees well with experiment results,and perturbation model errors of four sensing channels are within 25%.The attached eddy current sensor is capable of testing the crack nondestructively and measuring the crack extension quantitatively with the accuracy of 1mm. 展开更多
关键词 attached EDDY CURRENT sensor SEMI-ANALYTICAL model
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Free vibration of a sagged cable with attached discrete elements
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作者 W.PAKOS 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第5期631-648,共18页
An algorithm is presented to analyze the free vibration in a system composed of a cable with discrete elements, e.g., a concentrated mass, a translational spring, and a harmonic oscillator. The vibrations in the cable... An algorithm is presented to analyze the free vibration in a system composed of a cable with discrete elements, e.g., a concentrated mass, a translational spring, and a harmonic oscillator. The vibrations in the cable are modeled and analyzed with the Lagrange multiplier formalism. Some fragments of the investigated structure are modeled with continuously distributed parameters, while the other fragments of the structure are modeled with discrete elements. In this case, the linear model of a cable with a small sag serves as a continuous model, while the elements, e.g., a translational spring, a concentrated mass, and a harmonic oscillator, serve as the discrete elements. The method is based on the analytical solutions in relation to the constituent elements, which, when once derived, can be used to formulate the equations describing various complex systems compatible with an actual structure. The numerical analysis shows that, the method proposed in this paper can be successfully used to select the optimal parameters of a system composed of a cable with discrete elements, e.g., to detune the frequency resonance of some structures. 展开更多
关键词 free vibration sagged CABLE with attachMENTS CONTINUOUS DISCRETE model
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