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Characteristics of long-distance mobile mRNAs from shoot to root in grafted plant species
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作者 Mengmeng Fu Zhen Xu +7 位作者 Huaying Ma Yifan Hao Ji Tian Yi Wang Xinzhong Zhang Xuefeng Xu Zhenhai Han Ting Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期25-37,共13页
Thousands of long-distance mobile mRNAs were identified from different grafting systems,based on high-throughput sequencing technology.Moreover,the long-distance delivery of RNAs was proved to involve multiple mechani... Thousands of long-distance mobile mRNAs were identified from different grafting systems,based on high-throughput sequencing technology.Moreover,the long-distance delivery of RNAs was proved to involve multiple mechanisms.Here,we analyzed the homology,motif,and tRNA-like structure(TLS)of long-distance mobile mRNAs identified by RNA-seq as well as the RNA-binding protein(RBP)in nine grafting combinations including Arabidopsis thaliana,Vitis vinifera,Cucumis sativus,Citrullus lanatus,Nicotiana benthamiana,Malus domestica,Pyrus spp.,Glycine max and Phaseolus vulgaris.Although several mRNAs were found to be shared in herbaceous,woody,and related species,the vast majority of long-distance mobile mRNAs were species-specific.Four non-specific movement-related motifs were identified,while the TLS was not necessary for mRNA long distance mobility.In addition,we found that RBPs were conserved among herbaceous and woody plants as well as related species.This paper reports a further in-depth analysis of the endogenous mechanisms by which the species-specific transportable m RNAs were selected by bioinformatics,in order to provide insights for future research on long-distance mobile mRNAs. 展开更多
关键词 Grafting combination long-distance mobile mRNA TLS RNA binding proteins
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Securing offshore resources development:A mathematical investigation into gas leakage in long-distance flexible pipes
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作者 Xiang-An Lu Liang-Liang Jiang +1 位作者 Jian-Sheng Zhang Min-Gui Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2734-2744,共11页
Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development.Under high pressure conditions,small molecular components of natural gas dissolve into the polymer inner liner of the flexib... Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development.Under high pressure conditions,small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space,incurring annular pressure build-up and/or production of acidic environment,which poses serious challenges to the structure and integrity of the flexible pipes.Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature,annular structure,external temperature.In a long-distance gas flexible pipe,moreover,gas permeation exhibits non-uniform features,and the gas permeated into the annular space flows along the metal gap.To assess the complex gas transport behavior in long-distance gas flexible pipes,a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes,the diffusion of gas in the inner liner,and the gas seepage in the annular space under varying permeable properties of the annulus.In addition,the effect of a variable temperature is accounted.A numerical calculation method is accordingly constructed to solve the coupling mathematical equations.The annular permeability was shown to significantly influence the distribution of annular pressure.As permeability increases,the annular pressure tends to become more uniform,and the annular pressure at the wellhead rises more rapidly.After annular pressure relief followed by shut-in,the pressure increase follows a convex function.By simulating the pressure recovery pattern after pressure relief and comparing it with test results,we deduce that the annular permeability lies between 123 and 512 m D.The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources. 展开更多
关键词 Offshore resources development Transport security long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation
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Beyond statistical significance:Embracing minimal clinically important difference for better patient care
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作者 Naveen Jeyaraman Madhan Jeyaraman +2 位作者 Swaminathan Ramasubramanian Sangeetha Balaji Sathish Muthu 《World Journal of Methodology》 2025年第1期33-41,共9页
The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the p... The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the patient's perspective.This comprehensive review analyzes the evolution,applications,and challenges of MCID across medical specialties,emphasizing its necessity in ensuring that clinical outcomes not only demonstrate statistical significance but also offer genuine clinical utility that aligns with patient expectations and needs.We discuss the evolution of MCID since its inception in the 1980s,its current applications across various medical specialties,and the methodologies used in its calculation,highlighting both anchor-based and distribution-based approaches.Furthermore,the paper delves into the challenges associated with the application of MCID,such as methodological variability and the interpretation difficulties that arise in clinical settings.Recommendations for the future include standardizing MCID calculation methods,enhancing patient involvement in setting MCID thresholds,and extending research to incorporate diverse global perspectives.These steps are critical to refining the role of MCID in patient-centered healthcare,addressing existing gaps in methodology and interpretation,and ensuring that medical interventions lead to significant,patient-perceived improvements. 展开更多
关键词 Minimal clinically important difference Patient-centered care Clinical relevance Global health
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Simulation of long-distance pipeline transportation properties of whole-tailings paste with high sliming 被引量:18
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作者 WU Ai-xiang RUAN Zhu-en +4 位作者 WANG Yi-ming YIN Sheng-hua WANG Shao-yong WANG Yong WANG Jian-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第1期141-150,共10页
Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproper... Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproperties of high sliming paste from a copper mine in China.Based on the rheological properties test,the pressure and velocity of pipeline and elbow are simulated by CFD under different mass concentrations and different stowing capacities.The results show that the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with high sliming and pumping agent at the same mass concentration,and the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with low sliming while without pumping agent.It is very important to add pumping agent to whole-tailings paste with high sliming,and the resistance changes with mass concentration and stowing capacity at the same cement-to-sand ratio of1:5and tailings-to-waste ratio of6:1.However,the change is just limited,that is to say,the paste transportation system is of good stability.Furthermore,at the elbow,the maximum pressure and velocity transfer to the outside of the pipe from the inside.However,lubricating layer is formed at the pipe wall because of high content of fine particles in whole-tailings paste,which will protect the elbow from abrasion.CFD provides an intuitive and accurate basis for pipeline transportation study,and would have a wider application space in the study of paste rheological properties and resistance reduction methods. 展开更多
关键词 whole-tailings paste long-distance transportation computational fluid dynamics
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Water hammer protection for diversion systems in front of pumps in long-distance water supply projects 被引量:4
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作者 Lin Shi Jian Zhang +3 位作者 Xiao-dong Yu Sheng Chen Wen-long Zhao Xu-yun Chen 《Water Science and Engineering》 EI CAS CSCD 2023年第2期211-218,共8页
For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention.... For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up. 展开更多
关键词 long-distance diversion pipeline Water supply Water hammer Overflow surge tank Regulating valve
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Study on the Technology of Supplying Water Safely by Long-Distance Pipeline 被引量:3
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作者 CHEN Yanbo YU Taipin +1 位作者 LIU Junhua ZHAO Hongbin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期80-85,共6页
The extensively built long-distance water transmission pipelines have become the main water sources for urban areas. To ensure the reliability and safety of the water supply, from the viewpoint of overall management, ... The extensively built long-distance water transmission pipelines have become the main water sources for urban areas. To ensure the reliability and safety of the water supply, from the viewpoint of overall management, it would be necessary to establish a system of information management for the pipeline. The monitoring, calculating and analyzing functions of the system serve to give controlling instructions and safe operating rules to the automatic equipment and technician, making sure the resistance coefficient distribution along the pipeline is reasonable; the hydraulic state transition is smooth when operating conditions change or water supply accidents occur, avoiding the damage of water hammer. This paper covered the composition structures of the information management system of long-distance water transmission pipelines and the functions of the subsystems, and finally elaborated on the approaches and steps of building a mathematics model for the analysis of dynamic hydraulic status. 展开更多
关键词 long-distance water transmission pipeline water supply security information management water hammer MODELING
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Study on the long-distance target apperception techniques for underwater vehicles 被引量:2
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作者 Yang Xudong Huang Jianguo Zhang Qunfei Tang Qi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期484-490,共7页
The limited physical size for autonomous underwater vehicles (AUV) or unmanned underwater vehicles (UUV) makes it difficult to acquire enough space gain for localizing long-distance targets. A new technique about ... The limited physical size for autonomous underwater vehicles (AUV) or unmanned underwater vehicles (UUV) makes it difficult to acquire enough space gain for localizing long-distance targets. A new technique about long-distance target apperception with passive synthetic aperture array for underwater vehicles is presented. First, a synthetic aperture-processing algorithm based on the FFT transform in the beam space (BSSAP) is introduced. Then, the study on the flank array passive long-distance apperception techniques in the frequency scope of 11-18 kHz is implemented from the view of improving array gains, detection probability and augmenting detected range under a certain sea environment. The results show that the BSSAP algorithm can extend the aperture effectively and improve detection probability. Because of the augment of the transmission loss, the detected range has the trend of decline with the increase of frequency under the same target source level. The synthesized array could improve the space gain by nearly 7 dB and SNR is increased by about 5 dB. The detected range is enhanced to nearly 2 km under the condition of 108-118 dB of the target source level for AUV system in measurement interval of nearly 1 s. 展开更多
关键词 long-distance apperception synthetic aperture processing array gain detection probability detectedrange.
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个性化护理联合CICARE沟通模式在耳鼻喉门诊患者中的应用
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作者 吕国苹 田志森 张帆 《齐鲁护理杂志》 2024年第17期29-32,共4页
目的:探讨个性化护理联合CICARE沟通模式在耳鼻喉门诊患者中的应用效果。方法:采用便利取样法将2022年6月1日~2023年12月31日就诊于耳鼻喉门诊的256例患者作为研究对象,将2022年6月1日~2023年1月31日就诊的128例作为对照组,将2023年2月1... 目的:探讨个性化护理联合CICARE沟通模式在耳鼻喉门诊患者中的应用效果。方法:采用便利取样法将2022年6月1日~2023年12月31日就诊于耳鼻喉门诊的256例患者作为研究对象,将2022年6月1日~2023年1月31日就诊的128例作为对照组,将2023年2月1日~12月31日就诊的128例作为实验组;对照组给予常规耳鼻喉门诊护理,实验组给予个性化护理联合CICARE沟通模式;比较两组护理前后护理质量、护理满意度。结果:护理后,实验组有形性感知、可靠性感知、响应性感知、保证性感知评分均高于对照组(P<0.05,P<0.01),两组移情性感知比较差异无统计学意义(P>0.05);护理后,实验组服务态度、沟通能力、就诊秩序、专业素质、护理安全、护理满意度总分均高于对照组(P<0.05,P<0.01)。结论:将个性化护理联合CICARE沟通模式应用于耳鼻喉门诊患者中,能够提高护理质量和护理满意度。 展开更多
关键词 个性化护理 CIcare沟通模式 耳鼻喉门诊
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Long-distance propagation of pseudo-partially coherent Gaussian Schell-model beams in atmospheric turbulence 被引量:2
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作者 钱仙妹 朱文越 饶瑞中 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期259-266,共8页
Propagation properties of spatially pseudo-partially coherent Gaussian Schell-model beams through the atmo- spheric turbulence over a long-distance uplink path are studied by numerical simulation. A linear coordinatio... Propagation properties of spatially pseudo-partially coherent Gaussian Schell-model beams through the atmo- spheric turbulence over a long-distance uplink path are studied by numerical simulation. A linear coordination trans- formation is introduced to overcome the window effect and the loss-of-resolution problem. The beam spreading, beam wandering, and intensity scintillation as functions of turbulence strength, source correlation length, and change fre- quency of random phase that models the partial coherence of the source are analyzed. It is found that the beam spreading and the intensity scintillation of the partially coherent beam are less affected by the turbulence than those of the coherent one, but it suffers from a more severe diffractive effect, and the change frequency of random phase has no evident influence on it. The beam wandering is insensitive to the variation of source correlation length, and decreases firstly then goes to a fixed value as the change frequency increases. 展开更多
关键词 long-distance propagation pseudo-partially coherent Caussian Schell-model beam at-mospheric turbulence numerical simulation
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Improvement of heat-tolerance by training I. Evaluation of effects of long-distance running and march training on heat-tolerance 被引量:1
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作者 邱仞之 甄洪钧 +3 位作者 朱受成 万为人 刘汉湘 华旭初 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第3期220-226,共7页
in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6~35.6℃) and 10 km running (WBGT 25.0~31.1℃) were performed in laboratory and field under hot climate.Ten to twelve ... in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6~35.6℃) and 10 km running (WBGT 25.0~31.1℃) were performed in laboratory and field under hot climate.Ten to twelve times (days) of training were carried out 展开更多
关键词 MARCH long-distance running TRAINING HEAT ACCLIMATIZATION heat-tolerance infantryman
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Influencing Factors of Seed Long-distance Dispersal on a Fragmented Forest Landscape on Changbai Mountains,China 被引量:1
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作者 ZHAO Fuqiang QI Lin +1 位作者 FANG Lei YANG Jian 《Chinese Geographical Science》 SCIE CSCD 2016年第1期68-77,共10页
Seed long-distance dispersal(LDD) events are typically rare, but are important in the population processes that determine large-scale forest changes and the persistence of species in fragmented landscapes. However, pr... Seed long-distance dispersal(LDD) events are typically rare, but are important in the population processes that determine large-scale forest changes and the persistence of species in fragmented landscapes. However, previous studies focused on species dispersed via animal-mediated LDD, and ignored those dispersed by wind. The aim of this study was to assess the effects of canopy openness, edge, seed source, and patch tree density on the LDD of seeds by wind in forest. We collected birch seeds, a typical wind-dispersed species, throughout a larch plantation. We then assessed the relationship between birch LDD and each factor that may influence LDD of seeds by wind including distance to edge, canopy openness size, distance to mature forest, and the tree density of the larch plantation. We used univariate linear regression analysis to assess the influence of those factors on birch LDD, and partial correlations to calculate the contribution of each factor to LDD. The results showed that both canopy openness and edge had significant influences on birch LDD. Specifically, a negative relationship was observed between distance to edge and birch LDD, whereas there was a positive correlation between canopy openness size and LDD. In contrast, the distance to the mature forest was not correlated with birch LDD. Our results suggest that patch tree density could potently affect the probability of LDD by wind vectors, which provides novel and revealing insights regarding the effect of fragmentation on wind dynamics. The data also provide compelling evidence for the previously undocumented effect of habitat fragmentation on wind-dispersed organisms. As such, these observations will facilitate reasonable conservation planning, which requires a detailed understanding of the mechanisms by which patch properties hamper the delivery of seeds of wind-dispersed plants to fragmented areas. 展开更多
关键词 seed long-distance dispersal (LDD) forest fragmentation patch property wind dispersal Changbai Mountains
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Criterions and Measures of Route Selection of Shallowly Embedded Long-Distance Oil and Gas Pipeline in Mountain Areas 被引量:1
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作者 WANG Chenghua MA Qingwen +2 位作者 KONG Jiming CHEN Zefu LI Xiuzhen 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期787-792,共6页
According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows: the flat landform is the first choice in route alignment. The fo... According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows: the flat landform is the first choice in route alignment. The foot of mountain is the first choice when the route passes by the valley. The route should pass by but the shady and deposited slope and not in sunny and erosive slope as possible as it can. The pipeline should be vertical to contour climbing and descending the mountain except steep slope. Tunnel can be used in crossing foothill. Perpendicularly traversing the river is better than beveling; the worst choice is to put the pipeline along the river. Bypass is the best choice in karsts area. The order of route selection should be pre-choosing, investigation, optimization and adjustment. 展开更多
关键词 shallowly embedded long-distance oil and gas pipeline criterions and measures of route selection avoiding geological hazards
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Significant risk factors for intensive care unit-acquired weakness:A processing strategy based on repeated machine learning 被引量:10
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作者 Ling Wang Deng-Yan Long 《World Journal of Clinical Cases》 SCIE 2024年第7期1235-1242,共8页
BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective pr... BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective preventive measures.AIM To identify significant risk factors for ICU-AW through iterative machine learning techniques and offer recommendations for its prevention and treatment.METHODS Patients were categorized into ICU-AW and non-ICU-AW groups on the 14th day post-ICU admission.Relevant data from the initial 14 d of ICU stay,such as age,comorbidities,sedative dosage,vasopressor dosage,duration of mechanical ventilation,length of ICU stay,and rehabilitation therapy,were gathered.The relationships between these variables and ICU-AW were examined.Utilizing iterative machine learning techniques,a multilayer perceptron neural network model was developed,and its predictive performance for ICU-AW was assessed using the receiver operating characteristic curve.RESULTS Within the ICU-AW group,age,duration of mechanical ventilation,lorazepam dosage,adrenaline dosage,and length of ICU stay were significantly higher than in the non-ICU-AW group.Additionally,sepsis,multiple organ dysfunction syndrome,hypoalbuminemia,acute heart failure,respiratory failure,acute kidney injury,anemia,stress-related gastrointestinal bleeding,shock,hypertension,coronary artery disease,malignant tumors,and rehabilitation therapy ratios were significantly higher in the ICU-AW group,demonstrating statistical significance.The most influential factors contributing to ICU-AW were identified as the length of ICU stay(100.0%)and the duration of mechanical ventilation(54.9%).The neural network model predicted ICU-AW with an area under the curve of 0.941,sensitivity of 92.2%,and specificity of 82.7%.CONCLUSION The main factors influencing ICU-AW are the length of ICU stay and the duration of mechanical ventilation.A primary preventive strategy,when feasible,involves minimizing both ICU stay and mechanical ventilation duration. 展开更多
关键词 Intensive care unit-acquired weakness Risk factors Machine learning PREVENTION Strategies
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Long-Distance Pipe Jacking in Complex Urban Geological Environment 被引量:1
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作者 Yi Gong Yang Liu Qigao Li 《Journal of Architectural Research and Development》 2022年第1期7-12,共6页
A steel underground pipeline with a diameter of 2.4 m and a total length of 3,617 m(plate thickness of 26 mm)has been constructed in a city in central Hubei,and the engineering,procurement,and construction(EPC)project... A steel underground pipeline with a diameter of 2.4 m and a total length of 3,617 m(plate thickness of 26 mm)has been constructed in a city in central Hubei,and the engineering,procurement,and construction(EPC)project has been lifted from the upstream channel to supplement water to the downstream lake inside the city.Through preliminary geological survey data,site topographic and geomorphic survey,urban construction,as well as the requirements of the construction party,the preliminary arrangement of working wells and receiving wells as well as the selection and customization of pipe jacking machines have been proposed.Frequency conversion motor and remote monitoring technology are adopted for geotechnical change and long-distance pipe jacking.Through detailed survey,the rock and soil change section as well as gradual change conditions have been determined,the accuracy of construction mechanics calculation and construction operation control have improved,the basis and analysis basis are provided,and some experiences in construction operation are summarized. 展开更多
关键词 long-distance pipe jacking Complex geology Urban area New technology
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THE RISK ASSESSMENT OF THE LONG-DISTANCE OILPIPELINE ENGINEERING
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作者 Wang Jinghua Mu Congru(Institute of Geography, CAS, Beijing 100101People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第1期78-83,共6页
The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development o... The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development of oil industry , The risk assessment of oil industry has many subjects worthy to be studied.The major purpose of the paper is to research the risk cases of long-distance oil pipeline engineering in Ganshu and Shaanxi provinces. 展开更多
关键词 long-distance oil pipeline risk assessment ENGINEERING GANSU SHAANXI
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Long-distance super-exchange and quantum magnetic relaxation in a hybrid metal–organic framework
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作者 田英 申世鹏 +3 位作者 丛君状 闫丽琴 柴一晟 孙阳 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期390-393,共4页
The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-... The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-(Y-CH-O- Fe exchange path leads to a canted antiferromagnetic ordering at TN - 19 K, a second transition of magnetic blocking develops at TB- 9 K. The stair-shaped magnetization hysteresis loops below TB resemble the behaviors of resonant quantum tunneling of magnetization in single-molecular quantum magnets. Moreover, the magnetic relaxation also exhibits several features of resonant quantum relaxation, such as the exponential law with a single characteristic relaxation time, and the nonmonotonic dependence of relaxation rate on the applied magnetic field with a much faster relaxation around the resonant fields. The origin of quantum tunneling behaviors in the [(CH3)2NH2]Fe(HCOO)3 metal-organic framework is discussed in terms of magnetic phase separation due to the modification of hydrogen bonding on the long-distance super-exchange interaction. 展开更多
关键词 metal-organic frameworks resonant quantum relaxation long-distance super-exchange interac- tion hydrogen bonds
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Estimation of the Probability of Long-Distance Dispersal: Stratified Diffusion of <i>Spartina alterniflora</i>in the Yangtze River Estuary
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作者 Wei Yang Qing Wang +1 位作者 Xiaoyun Pan Bo Li 《American Journal of Plant Sciences》 2014年第24期3642-3651,共10页
The relative contribution of long-distance dispersal and local diffusion in the spread of invasive species has been a subject of much debate. Invasion of the intertidal mudflats by Spartina alterniflora is an ideal ex... The relative contribution of long-distance dispersal and local diffusion in the spread of invasive species has been a subject of much debate. Invasion of the intertidal mudflats by Spartina alterniflora is an ideal example of stratified diffusion, involving both long-distance dispersal of seeds and local diffusion due to clonal growth. In conjunction with experimental data on range radius-versus-time curve, a traveling wave equation-based model is used to investigate the sensitivity of the spread rate of exotic S. alterniflora to parameters of long distance dispersal (c, maximum colonial establishment rate) and local colony diffusion (r, intrinsic growth rate) at two tidal marshes, the Eastern Chongming and the Jiuduansha Islands, at the Yangtze River estuary. Both Eastern Chong ming and Jiuduansha Islands are now national natural reserves in China, which were established in 2005. However, the mudflats and salt marshes in the two reserves are now heavily infested with introduced S. alterniflora, which may threaten the estuarine ecosystems and their biodiversity. S. alterniflora was first found in 1995 on Chongming. For rapid sediment accretion in mudflats in the estuary, S. alterniflora was also intentionally introduced to Jiuduansha in 1997 and Chongming in 2001, which has led to a rapid range expansion in the estuary. Our results show that range expansion of species with stratified diffusion is affected by both long-distance dispersal and local colony diffusion, and that there is a critical c*, below which the spread rate is more influenced by long-distance dispersal than by local diffusion. After applying this model to the invasion of S. alterniflora in the Yangtze River estuary, we derive that c = 1.7 × 10-3, c* = 0.126 and c = 4.8 × 10-3 km-2·yr-1, c* = 0.140 km-2·yr-1 at Chongming and Jiuduansha (Shanghai), respectively. Our results suggest that the range spread of S. alterniflora in the Yangtze River estuary is more influenced by long-distance dispersal than local colony diffusion, and that S. alterniflora generates about 1.7 × 10-3 to 4.8 × 10-3 colonies per square kilometers per year. This study provides important information about dispersal dynamics of S. alterniflora that may be useful for finding optimal control strategies. · 展开更多
关键词 long-distance Dispersal STRATIFIED DIFFUSION Sensitivity Analysis Traveling Wave Equation SPARTINA alterniflora
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Electrochemical biosensors for point-of-care testing 被引量:1
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作者 Jinsol Kim Juho Jeong Seung Hwan Ko 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期548-565,共18页
Point-of-care testing(POCT)is the practice of diagnosing and monitoring diseases where the patient is located,as opposed to traditional treatment conducted solely in a medical laboratory or other clinical setting.POCT... Point-of-care testing(POCT)is the practice of diagnosing and monitoring diseases where the patient is located,as opposed to traditional treatment conducted solely in a medical laboratory or other clinical setting.POCT has been less common in the recent past due to a lack of portable medical devices capable of facilitating effective medical testing.However,recent growth has occurred in this field due to advances in diagnostic technologies,device miniaturization,and progress in wearable electronics.Among these developments,electrochemical sensors have attracted interest in the POCT field due to their high sensitivity,compact size,and affordability.They are used in various applications,from disease diagnosis to health status monitoring.In this paper we explore recent advancements in electrochemical sensors,the methods of fabricating them,and the various types of sensing mechanisms that can be used.Furthermore,we delve into methods for immobilizing specific biorecognition elements,including enzymes,antibodies,and aptamers,onto electrode surfaces and how these sensors are used in real-world POCT settings. 展开更多
关键词 Point-of-care testing(POCT) Electrochemical sensor ENZYME ANTIBODY Health care
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High-Performance Sodium Bose-Einstein Condensate Apparatus with a Hybrid Trap and Long-Distance Magnetic Transfer
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作者 张峰 龙云 +3 位作者 杨江陵 马国强 殷冀平 王如泉 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期51-54,共4页
We report on the production of large sodium Bose^Einstein condensates in a hybrid of magnetic quadrupole and optical dipole trap. With an optimized spin-flip Zeeman slower, 2 ~ 1010 sodium atoms are captured in the ma... We report on the production of large sodium Bose^Einstein condensates in a hybrid of magnetic quadrupole and optical dipole trap. With an optimized spin-flip Zeeman slower, 2 ~ 1010 sodium atoms are captured in the magneto-optical trap (MOT). A long distance magnetic transfer setup moves the cold atom over 46cm from the MOT chamber to the UHV science chamber, which provides great optical access and long conservative trap lifetime. After evaporative cooling in the hybrid trap, we produce nearly pure condensates of 1 ~ 107 atoms with lifetime of 80 s in the optical dipole trap. 展开更多
关键词 MOT High-Performance Sodium Bose-Einstein Condensate Apparatus with a Hybrid Trap and long-distance Magnetic Transfer BEC
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Research on the Long-distance Transmission
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作者 Xueli Wu Xiuyuan Yang +1 位作者 Hong Shen Qinyong Zhou 《Energy and Power Engineering》 2013年第4期1293-1297,共5页
In view of the imbalanced distribution of power load and resources, including the status of “electric shortage” in some cities in our country, the article discusses the long-distance transmission technology. It main... In view of the imbalanced distribution of power load and resources, including the status of “electric shortage” in some cities in our country, the article discusses the long-distance transmission technology. It mainly analyzed two ways of the long-distance transmission: UHV AC transmission and UHV DC transmission. The fractional frequency transmission technology and half wavelength AC transmission technology of AC transmission are introduced. Some key technologies of long-distance transmission are described. It has a guess for long-distance transmission future direction. 展开更多
关键词 Energy long-distance Ultra-high VOLTAGE (UHV) ALTERNATING CURRENT (AC) Direct CURRENT (DC) TRANSMISSION
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