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Overexpression of the transcription factor MdWRKY115 improves drought and osmotic stress tolerance by directly binding to the MdRD22 promoter in apple 被引量:1
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作者 Qinglong Dong Yi Tian +9 位作者 Xuemei Zhang Dingyue Duan He Zhang Kaiyu Yang Peng Jia Haoan Luan Suping Guo Guohui Qi Ke Mao Fengwang Ma 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期629-640,共12页
Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drou... Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple. 展开更多
关键词 APPLE MdWRKY115 osmotic stress Drought stress Function analysis
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The CBL-interacting protein kinase OsCIPK1 phosphorylated by SAPK10 positively regulates responses to ABA and osmotic stress in rice
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作者 Caihua Qin Xing Fan +2 位作者 Qianqian Fang Lan Ni Mingyi Jiang 《The Crop Journal》 SCIE CSCD 2024年第2期364-374,共11页
SubclassⅢsucrose nonfermenting1-related protein kinase 2s(SnRK2s)function in ABA and abiotic stress responses by unknown mechanisms.We found that osmotic stress/ABA-activated protein kinase 10(SAPK10),a member of ric... SubclassⅢsucrose nonfermenting1-related protein kinase 2s(SnRK2s)function in ABA and abiotic stress responses by unknown mechanisms.We found that osmotic stress/ABA-activated protein kinase 10(SAPK10),a member of rice SnRK2s,physically interacted with CBL-interacting protein kinase 1(OsCIPK1).OsCIPK1 expression was up-regulated by ABA and PEG treatment,and overexpression increased the ABA sensitivity of seed germination and root growth and plant osmotic stress tolerance.Osmotic stress or ABA-induced activation of OsCIPK1 is dependent on SAPK10.SAPK10 phosphorylates Thr-24 of OsCIPK1 in vitro,and this phosphorylation increases the activity of OsCIPK1 and positively regulates the function of OsCIPK1 in ABA responses and plant osmotic stress tolerance.This study suggests that OsCIPK1 is a direct phosphorylated substrate of SAPK10,and SAPK10-mediated phosphorylation of OsCIPK1 functions in ABA signaling and increases rice osmotic stress tolerance. 展开更多
关键词 RICE ABA osmotic stress OsCIPK1 SAPK10
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Impact of Osmotic Pressure on Seepage in Shale Oil Reservoirs
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作者 Lijun Mu Xiaojia Xue +2 位作者 Jie Bai Xiaoyan Li Xueliang Han 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1365-1379,共15页
Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the sh... Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the shut-in phase in augmenting shale oil productivity.Unlike conventional reservoirs,shale oil reservoirs exhibit characteristics such as low porosity,low permeability,and rich content of organic matter and clay minerals.Notably,the osmotic pressure effects occurring between high-salinity formation water and low-salinity fracturing fluids are significant.The current understanding of the mobilization patterns of crude oil in micro-pores during the imbibition process remains nebulous,and the mechanisms underpinning osmotic pressure effects are not fully understood.This study introduces a theoretical approach,by which a salt ion migration control equation is derived and a mathematical model for spontaneous imbibition in shale is introduced,which is able to account for both capillary and osmotic pressures.Results indicate that during the spontaneous imbibition of low-salinity fluids,osmotic effects facilitate the migration of external fluids into shale pores,thereby complementing capillary forces in displacing shale oil.When considering both capillary and osmotic pressures,the calculated imbibition depth increases by 12%compared to the case where only capillary forces are present.The salinity difference between the reservoir and the fracturing fluids significantly influences the imbibition depth.Calculations for the shutin phase reveal that the pressure between the matrix and fractures reaches a dynamic equilibrium after 28 days of shut-in.During the production phase,the maximum seepage distance in the target block is approximately 6.02 m. 展开更多
关键词 Shale oil osmotic pressure numerical simulation effective seepage distance
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Plasma‐oxidized 2D MXenes subnanochannel membrane for high‐performance osmotic energy conversion
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作者 Zhengmao Ding Tiancheng Gu +5 位作者 Rui Zhang Shouyi Sun Kaiqiang Wang Hanli Zhang Jinjin Li Yunjun Luo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期178-191,共14页
Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,ene... Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,energy conversion through nanofluidic channels is still facing considerable challenges.Here,a facile and efficient strategy to enhance osmotic energy harvesting based on drastically increasing surface charge density of MXenes subnanochannels via oxygen plasma is proposed.This plasma could break Ti–C bonds in the MXenes subnanochannels and effectively facilitate the formation of more Ti–O,C═O,O–OH,and rutile with a stronger negative charge and work function,which leads the surface potential of MXenes membrane to increase from 205 to 430 mV.This significant rise of surface charge endows the MXenes membrane with high cation selectivity,which could make the output power density of the MXenes membrane increase by 248.2%,reaching a high value of 5.92Wm^(−2)in the artificial sea‐river water system.Furthermore,with the assistance of low‐quality heat at 50℃,the osmotic power is enhanced to an ultrahigh value of 9.68Wm^(−2),which outperforms those of the state‐of‐the‐art two‐dimensional(2D)nanochannel membranes.This exciting breakthrough demonstrates the enormous potential of the facile plasma‐treated 2D membranes for osmotic energy harvesting. 展开更多
关键词 ion transport MXenes membranes osmotic energy harvesting PLASMA two‐dimensional nanochannels
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Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator
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作者 Jens Müller Sebastian Leonow +2 位作者 Johannes Schulz Christian Hansen Martin Monnigmann 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1346-1353,共8页
This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this m... This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation. 展开更多
关键词 BACKFLOW Progressing cavity pump Virtual sensor WEAR
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Optimal Design of High-Speed Partial Flow Pumps using Orthogonal Tests and Numerical Simulations
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作者 Jiaqiong Wang Tao Yang +2 位作者 Chen Hu Yu Zhang Ling Zhou 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1203-1218,共16页
To investigate the influence of structural parameters on the performances and internal flow characteristics of partial flow pumps at a low specific speed of 10000 rpm,special attention was paid to the first and second... To investigate the influence of structural parameters on the performances and internal flow characteristics of partial flow pumps at a low specific speed of 10000 rpm,special attention was paid to the first and second stage impeller guide vanes.Moreover,the impeller blade outlet width,impeller inlet diameter,blade inclination angle,and number of blades were considered for orthogonal tests.Accordingly,nine groups of design solutions were formed,and then used as a basis for the execution of numerical simulations(CFD)aimed at obtaining the efficiency values and heads for each design solution group.The influence of impeller geometric parameters on the efficiency and head was explored,and the“weight”of each factor was obtained via a range analysis.Optimal structural parameters were finally chosen on the basis of the numerical simulation results,and the performances of the optimized model were verified accordingly(yet by means of CFD).Evidence is provided that the increase in the efficiency and head of the optimized model was 12.11%and 23.5 m,respectively,compared with those of the original model. 展开更多
关键词 HIGH-SPEED partial flow pump orthogonal test optimal design numerical calculation
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JA-mediated MYC2/LOX/AOS feedback loop regulates osmotic stress response in tea plant
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作者 Junyan Zhu Hongrong Chen +5 位作者 Lu Liu Xiaobo Xia Xiaomei Yan Xiaozeng Mi Shengrui Liu Chaoling Wei 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期931-946,共16页
Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an i... Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an important phytohormone involving in plant stress.However,underlying molecular mechanisms of JA modulated osmotic stress response remains unclear.In this study,high concentration of mannitol induced JA accumulation and increase of peroxidase activity in tea plant.Integrated transcriptome mined a JA signaling master,MYC2 transcription factor is shown as a hub regulator that induced by mannitol,expression of which positively correlated with JA biosynthetic genes(LOX and AOS)and peroxidase genes(PER).CsMYC2 was determined as a nuclei-localized transcription activator,furthermore,ProteinDNA interaction analysis indicated that CsMYC2 was positive regulator that activated the transcription of CsLOX7,CsAOS2,CsPER1 and CsPER3via bound with their promoters,respectively.Suppression of CsMYC2 expression resulted in a reduced JA content and peroxidase activity and osmotic stress tolerance of tea plant.Overexpression of CsMYC2 in Arabidopsis improved JA content,peroxidase activity and plants tolerance against mannitol stress.Together,we proposed a positive feedback loop mediated by CsMYC2,CsLOX7 and CsAOS2 which constituted to increase the tolerance of osmotic stress through fine-tuning the accumulation of JA levels and increase of POD activity in tea plant. 展开更多
关键词 Camellia sinensis Jasmonic acid(JA) MYC2 transcription factor Lipoxygenase(LOX) osmotic stress Peroxidase(POD) Reactive oxygen species(ROS)
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The advantages of using osmotic pumps in caerulein-induced pancreatitis in Wistar rats
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作者 刘旭盛 Glenn James Farrant +2 位作者 Fikri M Abu-zidan L. Jonathan Zwit John A. Windsor 《Journal of Medical Colleges of PLA(China)》 CAS 2000年第2期87-90,共4页
Objective: To establish a refined model of intravenous Caerulein-induced edematous pancreatitis in order to study the pathogenesis and therapeutic protocols of the disesase. Methods: Wistar rats were employed. The osm... Objective: To establish a refined model of intravenous Caerulein-induced edematous pancreatitis in order to study the pathogenesis and therapeutic protocols of the disesase. Methods: Wistar rats were employed. The osmotic pre-filled with Caerulein and saline was implanted into a subctaneous pocket in the left iliac fossa of the animal. Caerulein was then infused via femoral vein to induce pancreatitis. Results: Pathological examination revealed obvious tissue edema of the pancreas in the rat 6 h after Caerulein infusion. The gross appearance of the pancreas exhibited edema with a clear ’gel- like’ fluid separating the pancreatic Iobules. Interstitial edema and marked vacuolization without inflammatory infiltrations in the Caerulein-infused rats were observed with light microscopy. There was no remarkable remarkable changes in the pancer as of rats infused with normal saline. Conclusion: The advantages of using implantable osmotic pump to infuse Caerulein to rats are the facilitation of animal handling, unrestriction of animal movement in cages and reduction in time lost due to accli matization of the rat to new housing conditions. 展开更多
关键词 PANCREATITIS osmotic PUMP CAERULEIN
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As Planet Warms,Heat Pumps Get Hotter
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作者 Chris Palmer 《Engineering》 SCIE EI CAS CSCD 2023年第10期2-4,共3页
The heat pump,an old device dating back to the early 1850s[1],has captured new attention for its potential to help meet climate change goals.Driven in large part by legislated incentives and bans on fossil-fuel heatin... The heat pump,an old device dating back to the early 1850s[1],has captured new attention for its potential to help meet climate change goals.Driven in large part by legislated incentives and bans on fossil-fuel heating in a growing number of countries,the heightened interest has also spawned improvements in the technology’s efficiency and cost.Another unique benefit is for one device to provide,depending on seasonal needs,both heating and cooling. 展开更多
关键词 PUMP PUMP DATING
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Long-term decay of the water pressure in the osmotic tensiometer
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作者 Hengshuo Liu Harianto Rahardjo +1 位作者 Hejun Du Abdul Halim Hamdany 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期738-746,共9页
Matric suction is an important state variable required for the assessment of unsaturated soil properties.Tensiometers are commonly used for direct matric suction measurement but have a limited measuring range up to 90... Matric suction is an important state variable required for the assessment of unsaturated soil properties.Tensiometers are commonly used for direct matric suction measurement but have a limited measuring range up to 90 kPa due to the cavitation problem.Osmotic tensiometer(OT)can improve the measuring range of tensiometers by increasing the osmotic pressure of water to avoid the cavitation.However,the long-term water pressure decay that appeared in OTs caused a gradual decrease in their measuring range.In this study,crosslinked poly(acrylamide-co-acrylic acid)potassium salt(PAM-co-PAAK)was used for the preparation of OTs(five in total)to explore the mechanism of water pressure decay of OTs.The maximum water pressure in the OT versus the volume fraction of polymer filled in the OT was described based on the Flory-Huggins polymer theories and validated using WP4C dewpoint hygrometer.The long-term pressure decay of OT-1,OT-2,and OT-3 was observed for 130 d and constant pressures were found for OT-1 and OT-2,indicating that the pressure decay of OT was mainly caused by the stress relaxation of the polymer hydrogels,and standard linear solid(SLS)rheological model was appropriate to fit the decay data.For OT-1,OT-2 and OT-3,the theoretical osmotic pressure that was calculated based on the mass of retrieved polymer from OTs after 130-d pressure observation was higher than the actual osmotic pressure as observed,indicating that polymer leakage cannot explain the pressure decay of the OT.The ultravioletevisible(UVevisible)spectrophotometry examined the change in polymer concentrations in the water containers of OT-4 and OT-5 and demonstrated that there was no increase in polymer leakage during the period of pressure decay of OT-4 and OT-5.As a result,the pressure decay of OT was not caused by polymer leakage.The results of this research suggested that the viscoelastic properties of polymers should be taken into consideration in further OT development. 展开更多
关键词 High suction measurement osmotic tensiometers Long-term pressure decay Polymer leakage Viscoelasticity of polymers
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Factors of Pumping Capacity in Some Different Types of Channel Brownian Pumps
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作者 谢嘉泳 《Journal of Donghua University(English Edition)》 CAS 2023年第3期326-333,共8页
The motion of particles in different channel Brownian pumps can be described by Langevin equations,and the pumping capacity is a useful indicator to demonstrate the strength of a pump’s transportation ability.Via the... The motion of particles in different channel Brownian pumps can be described by Langevin equations,and the pumping capacity is a useful indicator to demonstrate the strength of a pump’s transportation ability.Via the simulation,there is always an optimal value of temperature and unbiased external force for different pumps which make the concentration ratio between the right tube and left tube derive its maximum and minimum in two asymmetric tubes respectively.Besides,the concentration ratio will keep 1 regardless of radius,temperature or magnitude of force in the tube in a symmetric tube.To obtain more information about pumping capacity,exploring the average probability current(APC) of tubes in different conditions is necessary.Results indicate that as the concentration ratio is 1,the change of the APC when x_(0)=0 is similar to that when x_(0)=π.Also,when the concentration ratio is more than 1,there are optimal values of temperature,radius and magnitude of force where the APC gains a maximum,and the maximum decreases as the concentration in the right tube increases when x_(0)=0. 展开更多
关键词 Brownian pump pumping capacity unbiased external force average probability current(APC)
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Cavitation recognition of axial piston pumps in noisy environment based on Grad-CAM visualization technique
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作者 Qun Chao Xiaoliang Wei +2 位作者 Jianfeng Tao Chengliang Liu Yuanhang Wang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期206-218,共13页
The cavitation in axial piston pumps threatens the reliability and safety of the overall hydraulic system.Vibration signal can reflect the cavitation conditions in axial piston pumps and it has been combined with mach... The cavitation in axial piston pumps threatens the reliability and safety of the overall hydraulic system.Vibration signal can reflect the cavitation conditions in axial piston pumps and it has been combined with machine learning to detect the pump cavitation.However,the vibration signal usually contains noise in real working conditions,which raises concerns about accurate recognition of cavitation in noisy environment.This paper presents an intelligent method to recognise the cavitation in axial piston pumps in noisy environment.First,we train a convolutional neural network(CNN)using the spectrogram images transformed from raw vibration data under different cavitation conditions.Second,we employ the technique of gradient-weighted class activation mapping(Grad-CAM)to visualise class-discriminative regions in the spectrogram image.Finally,we propose a novel image processing method based on Grad-CAM heatmap to automatically remove entrained noise and enhance class features in the spectrogram image.The experimental results show that the proposed method greatly improves the diagnostic performance of the CNN model in noisy environments.The classification accuracy of cavitation conditions increases from 0.50 to 0.89 and from 0.80 to 0.92 at signal-to-noise ratios of 4 and 6 dB,respectively. 展开更多
关键词 axial piston pump cavitation recognition CNN Grad-CAM spectrogram image
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Experimental and Numerical Investigation on High-Pressure Centrifugal Pumps:Ultimate Pressure Formulation,Fatigue Life Assessment and Topological Optimization of Discharge Section
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作者 Abdourahamane Salifou Adam Hatem Mrad +1 位作者 Haykel Marouani Yasser Fouad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2845-2865,共21页
A high percentage of failure in pump elements originates from fatigue.This study focuses on the discharge section behavior,made of ductile iron,under dynamic load.An experimental protocol is established to collect the... A high percentage of failure in pump elements originates from fatigue.This study focuses on the discharge section behavior,made of ductile iron,under dynamic load.An experimental protocol is established to collect the strain under pressurization and depressurization tests at specific locations.These experimental results are used to formulate the ultimate pressure expression function of the strain and the lateral surface of the discharge section and to validate finite element modeling.Fe-Safe is then used to assess the fatigue life cycle using different types of fatigue criteria(Coffin-Manson,Morrow,Goodman,and Soderberg).When the pressure is under 3000 PSI,pumps have an unlimited service life of 107 cycles,regardless of the criterion.However,for a pressure of 3555 PSI,only the Morrow criterion denotes a significant decrease in fatigue life cycles,as it considers the average stress.The topological optimization is then applied to the most critical pump model(with the lowest fatigue life cycle)to increase its fatigue life.Using the solid isotropic material with a penalization approach,the Abaqus Topology OptimizationModule is employed.The goal is to reduce the strain energy density while keeping the volume within bounds.According to the findings,a 5%volume reduction causes the strain energy density to decrease from 1.06 to 0.66106 J/m^(3).According to Morrow,the fatigue life cycle at 3,555 PSI is 782,425 longer than the initial 309,742 cycles. 展开更多
关键词 Centrifugal pump ultimate pressure fatigue life topological optimization
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Influence of specific speed on hydraulic performances and pressure fluctuations in mixed-flow pumps
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作者 FU Yanxia JIA Qi +1 位作者 SHEN Yang PACE Giovanni 《排灌机械工程学报》 CSCD 北大核心 2023年第10期981-987,共7页
A series of steady and unsteady numerical calculations of the internal flow in mixed-flow pumps with three different specific speeds were carried out based on the N-S equation coupled with the standard k-εturbulence ... A series of steady and unsteady numerical calculations of the internal flow in mixed-flow pumps with three different specific speeds were carried out based on the N-S equation coupled with the standard k-εturbulence model under different operating conditions to investigate the relationship between the impeller specific speed and the pump performance as well as pressure pulsations.Meanwhile,the pump performance and pressure pulsations inside the mixed-flow pump with three different specific speeds were also analyzed and compared with the corresponding test data.From the results,the averaged deviations between the predicted and tested head among different impellers are below 5%,and with respect to the equivalent impeller specific speeds of 280 and 260,the values are 4.30%and 3.69%,respectively.For all the impeller schemes,the best efficiency point of the mixed-flow pump is found at the flow rate of 1.2 Q_(d) and the higher head deviation occurs at lower flow rates.Especially,it can be found that the specific speed has a slight effect on the pressure fluctuation in the impellers.Eventually,it is determined that the pump performance curves calculated by numerical simu-lations have good agreement with the relevant experimental results,which verifies that the numerical methods used in the present study are accurate to a certain extent.Furthermore,the results also provide some references to the pressure pulsation analysis and the performance improvement of the mixed-flow pump design. 展开更多
关键词 mixed-flow pumps impeller specific speed hydraulic performance pressure pulsation numerical simulation EXPERIMENT
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Adaptive strategy of Nitraria sibirica to transient salt,alkali and osmotic stresses via the alteration of Na+/K+fluxes around root tips
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作者 Xindi Mei Ting Dai Yingbai Shen 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期425-432,共8页
Nitraria sibirica Pall.is an important shrub with a strong salt-alkali tolerance,but the mechanism underlying this tolerance remains obscure.In this study,N.sibirica,with salt-sensitive Vigna radiata(Linn.)Wilczek as ... Nitraria sibirica Pall.is an important shrub with a strong salt-alkali tolerance,but the mechanism underlying this tolerance remains obscure.In this study,N.sibirica,with salt-sensitive Vigna radiata(Linn.)Wilczek as the control,was subjected to transient salt stress(100 mM NaCl),alkali stress(50 mM Na_(2)CO_(3)),and osmotic stress(175 mM mannitol).The ionic fluxes of Na^(+)and K^(+)in the root apical region were measured.Results show that,under salt and alkali stress,N.sibirica roots exhibited higher capacities to limit Na+influx and reduce K+efflux,thereby resulting in lower Na^(+)/K^(+)ratios compared with V.radiata roots.Alkali stress induced stronger Na^(+)influx and K+efflux in the root salt stress treatment;Na^(+)influx was mainly observed in the root cap,while K^(+)efflux was mainly observed in the elongation zone.While under osmotic stress,N.sibirica roots showed stronger Na+efflux and weaker K+efflux than V.radiata roots.Na+efflux was mainly observed in the root elongation zone,while K+efflux was in the root cap.These results reveal the ionic strategy of N.sibirica in response to transient salt,alkali,and osmotic stresses through the regulation of Na+/K+flux homeostasis. 展开更多
关键词 Nirtaria sibirica Na^(+)/K^(+)fl uxes Na^(+)/K^(+)ratios Salt stress Alkali stress osmotic stress
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Review:Measurement-Based Monitoring and Fault Identification in Centrifugal Pumps
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作者 Janani Shruti Rapur Rajiv Tiwari +1 位作者 Aakash Dewangan D.J.Bordoloi 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第2期25-47,共23页
Condition based maintenance(CBM) is one of the solutions to machinery maintenance requirements. Latest approaches to CBM aim at reducing human engagement in the real-time fault detection and decision making. Machine l... Condition based maintenance(CBM) is one of the solutions to machinery maintenance requirements. Latest approaches to CBM aim at reducing human engagement in the real-time fault detection and decision making. Machine learning techniques like fuzzy-logic-based systems, neural networks, and support vector machines help to reduce human involvement. Most of these techniques provide fault information with 100% confidence. It is undeniably apparent that this area has a vast application scope. To facilitate future exploration, this review is presented describing the centrifugal pump faults, the signals they generate, their CBM based diagnostic schemes, and case studies for blockage and cavitation fault detection in centrifugal pump(CP) by performing the experiment on test rig. The classification accuracy is above 98% for fault detection. This review gives a head-start to new researchers in this field and identifies the un-touched areas pertaining to CP fault diagnosis. 展开更多
关键词 centrifugal pumps condition-based maintenance fault diagnosis machine learning techniques REVIEW
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Synthesis and Design of Distillation Columns for Wide-Boiling Binary Mixtures with Vapor Recompression Heat Pumps
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作者 Shi Li 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第4期127-138,共12页
The vapor recompression heat pump(VRHP) distillation technology offers significant improvements in energy efficiency for distillation systems with small temperature differences between the top and bottom of the column... The vapor recompression heat pump(VRHP) distillation technology offers significant improvements in energy efficiency for distillation systems with small temperature differences between the top and bottom of the column. However, the separation of wide-boiling binary mixtures leads to substantial temperature differences between the top and bottom of the column. This limits the applicability of conventional VRHP due to high capital costs and strict performance requirements of the compressor. To overcome these challenges and to accommodate compressor operating conditions, a novel synthesis and design method is introduced to integrate VRHPs with wide-boiling binary mixture distillation columns(WBMDCs). This method enables quick determination of an initial configuration for the integrated WBMDC-VRHP system and helps identify the optimum configuration with the minimum total annual cost. Two examples, namely the separation of benzene/toluene and isopropanol/chlorobenzene, are employed to derive optimum configurations of the WBMDC-VRHP and compare them with the WBMDC. A systematic comparison between the WBMDC-VRHP and WBMDC demonstrates the superior steady-state performance and economic efficiency of the WBMDC-VRHP. 展开更多
关键词 vapor recompression heat pump wide-boiling binary mixtures distillation column energy saving synthesis and design
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珊瑚礁生态系统固碳过程及储碳机制研究进展 被引量:1
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作者 黄晖 袁翔城 +3 位作者 宋严 李颖心 周伟华 龙爱民 《热带海洋学报》 CAS CSCD 北大核心 2024年第3期13-21,共9页
珊瑚礁生态系统在全球碳循环和气候变化中发挥着重要作用。珊瑚礁生态系统是潜在的蓝色碳汇,我国珊瑚礁总面积约占全球的11%,每年的固碳量大约在3.5×10^(6)~4.5×10^(6)t之间。珊瑚礁生态系统的总储碳量非常巨大,同时珊瑚礁生... 珊瑚礁生态系统在全球碳循环和气候变化中发挥着重要作用。珊瑚礁生态系统是潜在的蓝色碳汇,我国珊瑚礁总面积约占全球的11%,每年的固碳量大约在3.5×10^(6)~4.5×10^(6)t之间。珊瑚礁生态系统的总储碳量非常巨大,同时珊瑚礁生态系统作为碳库在碳交易中具有非常大的潜在应用价值。文章综述了珊瑚礁生态系统中的固碳过程及储碳机制,包括碳酸盐泵、生物泵和微型生物碳泵,阐述了三种碳泵的研究进展。同时,针对目前研究存在的不足和问题,提出未来研究方向,以期为南海岛礁珊瑚礁生态系统的保护和管理提供科学依据。 展开更多
关键词 珊瑚礁 生态系统 固碳 碳酸盐泵 生物泵 微型生物碳泵
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流固耦合作用下深部岩石动态力学响应研究进展 被引量:1
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作者 夏开文 王峥 +2 位作者 吴帮标 徐颖 岳腾泷 《煤炭学报》 EI CAS CSCD 北大核心 2024年第1期454-478,共25页
深部岩石处于高地应力、高渗透压和强动态扰动的复杂地质环境之中,3者作用下岩石体更加容易发生损伤破裂,诱发突涌水、渗漏、井喷等工程地质灾害,因而探究流固耦合作用下岩石的动态力学响应是开展岩石工程建设的前提之一。近年来,国内... 深部岩石处于高地应力、高渗透压和强动态扰动的复杂地质环境之中,3者作用下岩石体更加容易发生损伤破裂,诱发突涌水、渗漏、井喷等工程地质灾害,因而探究流固耦合作用下岩石的动态力学响应是开展岩石工程建设的前提之一。近年来,国内外众多学者在考虑水和不同应力状态下的岩石动态力学实验研究方面取得了显著的成果。为给工程建设提供更加全面的指导并为后续研究奠定基础,从实验装置、测试结果以及围压与水的作用机理层面,对上述工作进行了回顾与总结。首先介绍了分离式霍普金森压杆测试装置的基本原理,以及用于模拟深部岩石赋存环境所进行的装置改进,包括围压分离式霍普金森压杆实验系统和孔压(渗透压)耦合的分离式霍普金森压杆实验系统,简要分析了各类装置在研究流固耦合作用下岩石动力学问题时的优势和不足。其次,总结了考虑不同应力状态(单向加载、三向围压加载)的流固耦合作用下岩石的动态力学响应特性。详细介绍了固定预设孔压、渗透压耦合作用下深部岩石的动态力学响应及其随孔隙水压、渗透压变化的规律。随后,概述了围压对岩石动力学性质的影响机理,分析了不同围压条件下的影响规律;总结了水对岩石动态力学性质的强化、弱化微观机制和定量表达。最后,对流固耦合作用下深部岩石的动态力学响应进行了概括总结,并对未来实验研究工作和深部赋存条件下岩石动态力学的研究方向进行了展望。 展开更多
关键词 流固耦合 岩石动力学 分离式霍普金森压杆 孔隙水压 渗透压
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基于锥形掺镱光纤实现20 kW高光束质量激光输出 被引量:1
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作者 肖虎 潘志勇 +15 位作者 陈子伦 马鹏飞 刘伟 杨欢 闫志平 王蒙 奚小明 李智贤 杨保来 杨林永 黄良金 黄值河 曹涧秋 王小林 王泽锋 陈金宝 《强激光与粒子束》 CAS CSCD 北大核心 2024年第1期94-96,共3页
锥形光纤能够有效兼顾非线性效应抑制和模式控制,具备实现高功率、高光束质量光纤激光的潜力。近期国防科技大学研制了锥形掺镱光纤,采用1 018 nm光纤激光后向级联泵浦实现了20.2 kW激光输出,光束质量β因子平均值优于2,拉曼抑制比为33... 锥形光纤能够有效兼顾非线性效应抑制和模式控制,具备实现高功率、高光束质量光纤激光的潜力。近期国防科技大学研制了锥形掺镱光纤,采用1 018 nm光纤激光后向级联泵浦实现了20.2 kW激光输出,光束质量β因子平均值优于2,拉曼抑制比为33 dB。研究结果展示了锥形光纤在实现万瓦级高光束质量激光方面的优势。 展开更多
关键词 光纤激光器 级联泵浦 锥形光纤 光束质量
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