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In-phase and out-of-phase spin pumping effects in Py/Ru/Pysynthetic antiferromagnetic structures
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作者 Zhaocong Huang Xuejian Tang +5 位作者 Qian Chen Wei Jiang Qingjie Guo Milad Jalali Jun Du Ya Zhai 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期541-545,共5页
The spin pumping effect in magnetic heterostructures and multilayers is a highly effective method for the generationand transmission of spin currents. In the increasingly prominent synthetic antiferromagnetic structur... The spin pumping effect in magnetic heterostructures and multilayers is a highly effective method for the generationand transmission of spin currents. In the increasingly prominent synthetic antiferromagnetic structures, the two ferromagneticlayers demonstrate in-phase and out-of-phase states, corresponding to acoustic and optical precession modes. Withinthis context, our study explores the spin pumping effect in Py/Ru/Py synthetic antiferromagnetic structures across differentmodes. The heightened magnetic damping resulting from the spin pumping effect in the in-phase state initially decreaseswith increasing Py thickness before stabilizing. Conversely, in the out-of-phase state, the amplified damping exceeds thatof the in-phase state, suggesting a greater spin relaxation within this configuration, which demonstrates sensitivity to alterationsin static exchange interactions. These findings contribute to advancing the application of synthetic antiferromagneticstructures in magnonic devices. 展开更多
关键词 SPIN pumping SPIN transmission synthetic ANTIFERROMAGNETIC STRUCTURES SPIN dynamics
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Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning
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作者 Yun-Peng He Hai-Bo Cheng +4 位作者 Peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期641-653,共13页
High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an eff... High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis method.However,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational effort.Additionally,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different moments.Thus,there is heterogeneity in field data,which can dramatically impair the diagnostic accuracy.To solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this paper.First,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC data.Subsequently,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data heterogeneity.Finally,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the 4S-TFSM.Experiments on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational cost.To the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS. 展开更多
关键词 Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix
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Ultra-Robust and High-Performance Rotational Triboelectric Nanogenerator by Bearing Charge Pumping
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作者 Xianpeng Fu Yuhan Qin +6 位作者 Zhi Zhang Guoxu Liu Jie Cao Beibei Fan Zhaozheng Wang Zheng Wang Chi Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期343-349,共7页
As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in pra... As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in practical applications.Here,an ultra-robust and high-performance rotational triboelectric nanogenerator(R-TENG)by bearing charge pumping is proposed.The R-TENG composes of a pumping TENG(P-TENG),an output TENG(O-TENG),a voltage-multiplying circuit(VMC),and a buffer capacitor.The P-TENG is designed with freestanding mode based on a rolling ball bearing,which can also act as the rotating mechanical energy harvester.The output low charge from the P-TENG is accumulated and pumped to the non-contact O-TENG,which can simultaneously realize ultralow mechanical wear and high output performance.The matched instantaneous power of R-TENG is increased by 32 times under 300 r/min.Furthermore,the transferring charge of R-TENG can remain 95%during 15 days(6.4×10^(6)cycles)continuous operation.This work presents a realizable method to further enhance the durability of TENG,which would facilitate the practical applications of high-performance TENG in harvesting distributed ambient micro mechanical energy. 展开更多
关键词 bearing charge pumping triboelectric nanogenerators ultralow mechanical wear ultra-robust voltage-multiplying circuit
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Pumpingline管道预制与安装研究——以2023 SH 二次配Pumping-line工程项目为例
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作者 张俊刚 《中国科技期刊数据库 工业A》 2024年第3期0195-0198,共4页
本文以中芯南方集成电路制造有限公司负责的2023?SH?二次配Pumping-line工程项目为例,首先对Pumping line管道预制与安装流程进行了简单介绍。在此基础上,本文围绕机台Pumping line会勘、Pumping line管道测量绘图作业、Pumping line管... 本文以中芯南方集成电路制造有限公司负责的2023?SH?二次配Pumping-line工程项目为例,首先对Pumping line管道预制与安装流程进行了简单介绍。在此基础上,本文围绕机台Pumping line会勘、Pumping line管道测量绘图作业、Pumping line管道的预制与现场安装作业要素、机台Monve-in定位后Hook up相关作业要素等展开分析,希望为相关从业人员提供一定的参考。 展开更多
关键词 pumping line管道 会勘 预制 现场安装
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Comparative Study of the Types of Photovoltaic Panels Used in Solar Pumping Systems in Dry Tropical Zones: Case of Adamawa Region in Cameroon
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作者 Boussaibo Andre Waoudowa Kande Veronique +1 位作者 Ndjiya Ngasop Stephane Gautier Kitmo 《Open Journal of Energy Efficiency》 2024年第3期79-87,共9页
In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two t... In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two types of solar panels, namely monocrystalline and polycrystalline. However, the part of the local market is more dominated by the polycrystalline panel. In this work, comparative studies are carried out in order to characterize the two types of solar panels with regard to local constraints. Tests were carried out over the course of the sun to establish the performance of each type. The panels used have the same electrical characteristics and are connected to loads with same characteristics. Under the set operating conditions, the monocrystalline panel presents more performance than the polycrystalline panel. Although the local market is dominated by the polycrystalline panel, dust deposition tests on the surface of the panels show that the performance of the polycrystalline panel is more affected compared to the performance of the monocrystalline panel. 展开更多
关键词 Solar pumping Monocrystalline Cell Polycrystalline Cell Dry tropical Zone Dustdeposit
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Adoption of Solar Pumping Systems by Vegetable Farmers in Niayes Agro-Ecological Zone of Senegal: Adoption as a Sequential Process
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作者 Abou Abdoulaye Sow Papa Yona Boubacar Mane +1 位作者 Mamma Sawaneh Halidou Kafando 《Journal of Power and Energy Engineering》 2024年第9期19-36,共18页
This article examines the determinants of the adoption of solar pumping systems (PV) by vegetable farmers in the Niayes area of Senegal. To measure the determinants, we used a sequential logit model to translate the a... This article examines the determinants of the adoption of solar pumping systems (PV) by vegetable farmers in the Niayes area of Senegal. To measure the determinants, we used a sequential logit model to translate the adoption process from becoming aware of solar pumping systems to testing them, i.e. using them at least once, and then continuing to use them over time. The results show that the main variables affecting awareness of the use of solar pumping systems (PV) are age, marital status, experience, access to credit, the farmer’s knowledge of climate change, the farmer’s origin in the Thiès region and length of time in the Niayes area. The first use of PVs is influenced by factors such as the size of the plot, the distance of the plot from the main road or from the market. Finally, the decision to adopt or continue use is influenced by gender, experience, household size and access to credit. Surprisingly, access to credit does not affect the first use of solar pumping systems, but plays a key role in their continued use. 展开更多
关键词 Solar pumping Systems ADOPTION Vegetable Cultivation Niayes (Senegal)
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Few-shot working condition recognition of a sucker-rod pumping system based on a 4-dimensional time-frequency signature and meta-learning convolutional shrinkage neural network 被引量:1
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作者 Yun-Peng He Chuan-Zhi Zang +4 位作者 Peng Zeng Ming-Xin Wang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1142-1154,共13页
The accurate and intelligent identification of the working conditions of a sucker-rod pumping system is necessary. As onshore oil extraction gradually enters its mid-to late-stage, the cost required to train a deep le... The accurate and intelligent identification of the working conditions of a sucker-rod pumping system is necessary. As onshore oil extraction gradually enters its mid-to late-stage, the cost required to train a deep learning working condition recognition model for pumping wells by obtaining enough new working condition samples is expensive. For the few-shot problem and large calculation issues of new working conditions of oil wells, a working condition recognition method for pumping unit wells based on a 4-dimensional time-frequency signature (4D-TFS) and meta-learning convolutional shrinkage neural network (ML-CSNN) is proposed. First, the measured pumping unit well workup data are converted into 4D-TFS data, and the initial feature extraction task is performed while compressing the data. Subsequently, a convolutional shrinkage neural network (CSNN) with a specific structure that can ablate low-frequency features is designed to extract working conditions features. Finally, a meta-learning fine-tuning framework for learning the network parameters that are susceptible to task changes is merged into the CSNN to solve the few-shot issue. The results of the experiments demonstrate that the trained ML-CSNN has good recognition accuracy and generalization ability for few-shot working condition recognition. More specifically, in the case of lower computational complexity, only few-shot samples are needed to fine-tune the network parameters, and the model can be quickly adapted to new classes of well conditions. 展开更多
关键词 Few-shot learning Indicator diagram META-LEARNING Soft thresholding Sucker-rod pumping system Time–frequency signature Working condition recognition
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Spin pumping by higher-order dipole-exchange spin-wave modes
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作者 王鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期531-536,共6页
Spin pumping(SP)and inverse spin Hall effect(ISHE)driven by parametrically-excited dipole-exchange spin waves in a yttrium iron garnet film have been systematically investigated.The measured voltage spectrum exhibits ... Spin pumping(SP)and inverse spin Hall effect(ISHE)driven by parametrically-excited dipole-exchange spin waves in a yttrium iron garnet film have been systematically investigated.The measured voltage spectrum exhibits a feature of the field-induced transition from parallel pumping to perpendicular pumping because of the inhomogeneous excitation geometry.Thanks to the high precision of the SP-ISHE detection,two sets of fine structures in the voltage spectrum are observed,which can correspond well to two kinds of critical points in the multimode spin-wave spectrum for magnetic films.One is the q=0 point of each higher-order dispersion branch,and the other is the local minimum due to the interplay between the dipolar and exchange interactions.These fine structures on the voltage spectrum confirm the spin pumping by higher-order dipole-exchange spin-wave modes,and are helpful for probing the multimode spin-wave spectrum. 展开更多
关键词 spin pumping parametric excitation spin-wave spectrum fine structures
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A cladding-pumping based power-scaled noise-like and dissipative soliton pulse fiber laser
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作者 吕志国 滕浩 魏志义 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期298-302,共5页
We report a high-average-power noise-like pulse(NLP) and dissipative soliton(DS) pulse fiber laser. Average power as high as 4.8 W could be obtained at the fundamental mode-locked repetition rate. The NLP can also be ... We report a high-average-power noise-like pulse(NLP) and dissipative soliton(DS) pulse fiber laser. Average power as high as 4.8 W could be obtained at the fundamental mode-locked repetition rate. The NLP can also be transformed into a more powerful DS mode-locking state by optimizing the polarization and losses of intra-cavity pulses in the nonlinear polarization evolution regime. The operation mode between the NLP and DS can be switched, and the laser output performance in both modes has been studied. The main advantage of this work is switchable high-power operation between the NLP and DS. In comparison with conventional single-mode NLP fiber lasers, the multi-function high-power optical source will greatly push its application in supercontinuum generation, coherence tomography, and industrial processing. 展开更多
关键词 cladding pumping high power noise-like pulse dissipative soliton
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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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Design and Operation of Municipal Rain and Sewage United Pumping Station
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作者 Ting Ting Liu 《Journal of Architectural Research and Development》 2023年第4期51-56,共6页
In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifica... In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifically select the location and layout,and select materials reasonably.After completing the process design of the municipal rainwater and sewage pumping station and putting it into operation,in order to ensure the normal and stable operation of the pumping station,it is necessary to focus on strengthening the operation and management of diving equipment,cleaning equipment,and electromechanical equipment.The author analyzes the key points and specific design path of the process design of municipal rainwater and sewage pumping stations,and puts forward effective strategies for operation management,hoping to contribute to the scientific design and stable operation of municipal rainwater and sewage pumping stations. 展开更多
关键词 Municipal administration Rainwater and sewage united pumping stations Design path Operation management
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Petri网语言的Pumping引理 被引量:13
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作者 蒋昌俊 刘关俊 《计算机学报》 EI CSCD 北大核心 2006年第2期274-278,共5页
Petri网语言是Petri网理论的重要组成部分,也是系统行为分析的一种重要的工具.Petri网语言的Pumping引理反映了Petri网语言的共性,可用来证明某些语言不是Petri网语言.已经证明,当一个Petri网语言可被某个有界Petri网产生时,此语言是正... Petri网语言是Petri网理论的重要组成部分,也是系统行为分析的一种重要的工具.Petri网语言的Pumping引理反映了Petri网语言的共性,可用来证明某些语言不是Petri网语言.已经证明,当一个Petri网语言可被某个有界Petri网产生时,此语言是正规语言,因此,正规语言的Pumping引理对此语言是有效的,但正规语言的Pumping引理并不适用于所有的Petri网语言.文中给出了一种Petri网语言的Pumping引理,证明其对任意无空标注的Petri网语言都有效,并且正规语言的Pumping引理是此引理的一种特殊形式.利用此Pumping引理可以证明某些语言是不能由Petri网产生的. 展开更多
关键词 PETRI网 语言 正规语言 pumping引理
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Studies on the Proton Pumping Activity of H^+-ATPase in Tonoplast Vesicles of Populus euphratica 被引量:6
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作者 刘群录 张旭家 +2 位作者 李义 王沙生 蒋湘宁 《Acta Botanica Sinica》 CSCD 2001年第5期495-500,共6页
Tonoplast-enriched vesicles were prepared from suspension-cultured Populus euphratica Oliv. cells by differential centrifugation and discontinuous sucrose density gradient centrifugation. The properties of the proton ... Tonoplast-enriched vesicles were prepared from suspension-cultured Populus euphratica Oliv. cells by differential centrifugation and discontinuous sucrose density gradient centrifugation. The properties of the proton pumping activity of H+-ATPases in tonoplast vesicles were studied by acridine orange fluorescent quenching measured at 22 degreesC. The proton pumping activity of ATPase was ATP-dependent with apparent Michaelis-Menten Constant (K-m) for ATP about 0.65 mmol/L. The optimal pH for H+-ATPases activity was 7.5. The proton pumping activity of H+-ATPase could be initiated by some divalent cations, Mg2+ being highly efficient, much more than Fe2+; and Ca2+, Cu2+ and Zn2+ were inefficient under the experimental condition. The proton translocation could be stimulated by halide anions, with potencies decreasing in the order Cl- > Br- > I- > F-. The proton pumping activity was greatly inhibited by N-ethylmaleimide (NEM), N, N'-dicyclohexylcarbodiimide (DCCD), NO3- and Bafilomycin A(1), but not by orthovanadate and azide. These results demonstrated that the H+-ATPase in the tonoplast of Populus euphratica belonged to vacuolar type ATPase. This work was the first time that tonoplast-enriched vesicles were isolated from Populus euphratica cells. 展开更多
关键词 Populus euphratica H+-ATPase proton pumping activity
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Pumping引理的Petri网描述──Petri网语言属型的一组判定条件 被引量:33
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作者 吴哲辉 《计算机学报》 EI CSCD 北大核心 1994年第11期852-858,共7页
本文通过Pumping引理在Petri网的变迁节引发序列中的反映,揭示了对应的Petri网结构内涵,从而给出了判定一个标准Petri网产生的语言分别为正规语言或上下文无关语言的充要条件.这样,就可以从网的结构直接判断... 本文通过Pumping引理在Petri网的变迁节引发序列中的反映,揭示了对应的Petri网结构内涵,从而给出了判定一个标准Petri网产生的语言分别为正规语言或上下文无关语言的充要条件.这样,就可以从网的结构直接判断其语言属型. 展开更多
关键词 形式语言 pumping引理 PETRI网 PETRI网语言
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上下文无关Petri网语言的Pumping引理 被引量:3
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作者 张继军 吴哲辉 《小型微型计算机系统》 CSCD 北大核心 2008年第4期698-702,共5页
Petri网语言可分为正规Petri网语言、上下文无关Petri网语言和Petri网语言三类,Pumping引理反映了一类语言的共性.对于正规Petri网语言类和Petri网语言类都已给出了其相应的Pumping引理,而对于上下文无关Petri网语言类的Pumping引理却... Petri网语言可分为正规Petri网语言、上下文无关Petri网语言和Petri网语言三类,Pumping引理反映了一类语言的共性.对于正规Petri网语言类和Petri网语言类都已给出了其相应的Pumping引理,而对于上下文无关Petri网语言类的Pumping引理却一直未给出.本文通过分析上下文无关Petri网语言的结构性质,给出了上下文无关Petri网语言的Pumping引理,并且正规Petri网语言的Pumping引理是上下文无关Petri网语言的Pumping引理的一种特殊形式,而上下文无关Petri网语言的Pump-ing引理又是Petri网语言Pumping引理的一种特殊形式,从而完整地解决了三类Petri网语言Pumping引理以及它们之间的关系. 展开更多
关键词 pumping引理 语言 PETRI网 上下文无关语言
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An NMOS output-capacitorless low-dropout regulator with dynamic-strength event-driven charge pump 被引量:1
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作者 Yiling Xie Baochuang Wang +1 位作者 Dihu Chen Jianping Guo 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期23-34,共12页
In this paper,an NMOS output-capacitorless low-dropout regulator(OCL-LDO)featuring dual-loop regulation has been proposed,achieving fast transient response with low power consumption.An event-driven charge pump(CP)loo... In this paper,an NMOS output-capacitorless low-dropout regulator(OCL-LDO)featuring dual-loop regulation has been proposed,achieving fast transient response with low power consumption.An event-driven charge pump(CP)loop with the dynamic strength control(DSC),is proposed in this paper,which overcomes trade-offs inherent in conventional structures.The presented design addresses and resolves the large signal stability issue,which has been previously overlooked in the event-driven charge pump structure.This breakthrough allows for the full exploitation of the charge-pump structure's poten-tial,particularly in enhancing transient recovery.Moreover,a dynamic error amplifier is utilized to attain precise regulation of the steady-state output voltage,leading to favorable static characteristics.A prototype chip has been fabricated in 65 nm CMOS technology.The measurement results show that the proposed OCL-LDO achieves a 410 nA low quiescent current(IQ)and can recover within 30 ns under 200 mA/10 ns loading change. 展开更多
关键词 output-capacitorless low-dropout regulator fast transient low quiescent current event-driven charge pump
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Hydrocarbon accumulation characteristics in basement reservoirs and exploration targets of deep basement reservoirs in onshore China
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作者 WANG Zecheng JIANG Qingchun +10 位作者 WANG Jufeng LONG Guohui CHENG Honggang SHI Yizuo SUN Qisen JIANG Hua ABULIMITI Yiming CAO Zhenglin XU Yang LU Jiamin HUANG Linjun 《Petroleum Exploration and Development》 SCIE 2024年第1期31-43,共13页
Based on the global basement reservoir database and the dissection of basement reservoirs in China,the characteristics of hydrocarbon accumulation in basement reservoirs are analyzed,and the favorable conditions for h... Based on the global basement reservoir database and the dissection of basement reservoirs in China,the characteristics of hydrocarbon accumulation in basement reservoirs are analyzed,and the favorable conditions for hydrocarbon accumulation in deep basement reservoirs are investigated to highlight the exploration targets.The discovered basement reservoirs worldwide are mainly buried in the Archean and Precambrian granitic and metamorphic formations with depths less than 4500 m,and the relatively large reservoirs have been found in rift,back-arc and foreland basins in tectonic active zones of the Meso-Cenozoic plates.The hydrocarbon accumulation in basement reservoirs exhibits the characteristics in three aspects.First,the porous-fractured reservoirs with low porosity and ultra-low permeability are dominant,where extensive hydrocarbon accumulation occurred during the weathering denudation and later tectonic reworking of the basin basement.High resistance to compaction allows the physical properties of these highly heterogeneous reservoirs to be independent of the buried depth.Second,the hydrocarbons were sourced from the formations outside the basement.The source-reservoir assemblages are divided into contacted source rock-basement and separated source rock-basement patterns.Third,the abnormal high pressure in the source rock and the normal–low pressure in the basement reservoirs cause a large pressure difference between the source rock and the reservoirs,which is conducive to the pumping effect of hydrocarbons in the deep basement.The deep basement prospects are mainly evaluated by the factors such as tectonic activity of basement,source-reservoir combination,development of large deep faults(especially strike-slip faults),and regional seals.The Precambrian crystalline basements at the margin of the intracontinental rifts in cratonic basins,as well as the Paleozoic folded basements and the Meso-Cenozoic fault-block basements adjacent to the hydrocarbon generation depressions,have favorable conditions for hydrocarbon accumulation,and thus they are considered as the main targets for future exploration of deep basement reservoirs. 展开更多
关键词 basement reservoir granite reservoir source-reservoir assemblage pumping effect strike-slip fault deep basement reservoir
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Relationship between mitochondrial respiratory dysfunction of blood mononuclear cells and heart failure severity
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作者 Viacheslav A.Korepanov Tariel A.Atabekov +2 位作者 Tatiana Yu.Rebrova Roman E.Batalov Sergey A.Afanasiev 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第1期130-134,共5页
Chronic heart failure(CHF)is a clinical syndrome manifested by reduced pumping ability of the heart,increased pressure in heart chambers in both physical activity and at rest.The symptoms of this syndrome are dyspnea,... Chronic heart failure(CHF)is a clinical syndrome manifested by reduced pumping ability of the heart,increased pressure in heart chambers in both physical activity and at rest.The symptoms of this syndrome are dyspnea,undue fatigability,peripheral edema,which follow structural and functional changes of the myocardium.[1]The growing incidence of CHF,especially among elderly people,is an urgent problem for medicine in the vast majority of industrialized countries.For instance,in Russian Federation,CHF is diagnosed in about 7%of cardiovascular patients.At the same time,this indicator varies from 0.3%in young people(20-29 years old)to 70%in the older age group.[2,3]. 展开更多
关键词 SEVERITY instance pumping
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Transport Properties of Two Coupled Quantum Dots Under Optical Pumping
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作者 葛传楠 温俊 +1 位作者 彭菊 王伯根 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期598-603,共6页
Using the Keldysh-Green function,we present a theoretical study on the electron transport properties of two coupled quantum dots under optical pumping. Plateaus in the I-V curve and resonant peaks in the transmission ... Using the Keldysh-Green function,we present a theoretical study on the electron transport properties of two coupled quantum dots under optical pumping. Plateaus in the I-V curve and resonant peaks in the transmission coefficient occur and can be explained by the local electron density of states in the quantum dots. The effects of the optical pumping frequency and intensity on the transport properties of the system are also discussed. The electron dynamical localization phenomenon occurs when the optical pumping frequency is equal to the discrete hole energy level. This result can be used to realize optical control switches. 展开更多
关键词 Keldysh-Green function optical pumping quantum dot electron transport dynamical localization
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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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