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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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基于ParFlow.CLM的居民小区屋顶雨水断接水文效应研究
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作者 王瑶 王卫光 张翔 《中国农村水利水电》 北大核心 2024年第9期181-187,195,共8页
城市不透水面的快速扩张极大地改变了自然的水文循环过程,是造成城市内涝、河湖生态退化等城市水问题的主要原因之一。海绵城市建设及低影响开发利用源头海绵设施或城市绿地断接城市不透水面,减少不透水面的水文效应,是缓解城市水问题... 城市不透水面的快速扩张极大地改变了自然的水文循环过程,是造成城市内涝、河湖生态退化等城市水问题的主要原因之一。海绵城市建设及低影响开发利用源头海绵设施或城市绿地断接城市不透水面,减少不透水面的水文效应,是缓解城市水问题的重要措施。探究不透水面断接的水文效应对我国海绵城市建设具有重要意义。基于全分布式物理水文模型ParFlow.CLM,充分考虑城市地下构筑物,探究了不同土壤质地情景下西宁市某典型居民小区建筑屋顶断接在连续的降雨、蒸发过程中的水文效应。模拟结果显示,利用该居民小区自然绿地断接建筑屋顶能取得较好的径流控制效果:当土壤饱和导水率(K_(s))大于0.01m/h时,屋顶径流的年削减率能达到72.9%以上。屋顶断接在建筑物雨落管附近形成了集中入渗,增加了根区土壤湿度,且这一效应随着土壤渗透性的增加而增强。根区土壤湿度的增加进一步促进了绿地的蒸散发:与屋顶断接前相比,不同土壤质地情景下居民小区年蒸散发总量增加了6.2%~7.8%。另一方面,集中入渗在局部也形成了更深的湿润锋,使得更多下渗水量能够脱离植被根区的蒸散发作用,从而促进根区水分的深层渗漏。模拟结果表明,尽管该居民小区地下停车场限制了大部分区域的深层渗漏,当土壤K_(s)大于0.01m/h时,屋顶断接情景下的年深层渗漏总量仍能超过城市化前的水平。 展开更多
关键词 不透水面断接 海绵城市 低影响开发 ParFlow.CLM 城市地下构筑物
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Organic X-Ray Image Sensors Using a Medium Bandgap Polymer Donor with Low Dark Current
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作者 Jong-Woon Ha Seung Hun Eom +11 位作者 Bo Kyung Cha Seyeong Song Hyeong Ju Eun Jong H.Kim Jong Mok Park BongSoo Kim Byoungwook Park Seo-Jin Ko Sung Cheol Yoon Changjin Lee In Hwan Jung Do-Hoon Hwang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期230-237,共8页
The development of portable X-ray detectors is necessary for diagnosing fractures in unconscious patients in emergency situations.However,this is quite challenging because of the heavy weight of the scintillator and s... The development of portable X-ray detectors is necessary for diagnosing fractures in unconscious patients in emergency situations.However,this is quite challenging because of the heavy weight of the scintillator and silicon photodetectors.The weight and thickness of X-ray detectors can be reduced by replacing the silicon layer with an organic photodetectors.This study presents a novel bithienopyrroledione-based polymer donor that exhibits excellent photodetection properties even in a thick photoactive layer(~700 nm),owing to the symmetric backbone and highly soluble molecular structure of bithienopyrroledione.The ability of bithienopyrroledione-based polymer donor to strongly suppress the dark current density(Jd~10−10 A cm^(−2))at a negative bias(−2.0 V)while maintaining high responsivity(R=0.29 A W−1)even at a thickness of 700 nm results in a maximum shot-noise-limited specific detectivity of D_(sh)^(*)=2.18×10^(13)Jones in the organic photodetectors.Printed organic photodetectors are developed by slot-die coating for use in X-ray detectors,which exhibit D_(sh)^(*)=2.73×10^(12)Jones with clear rising(0.26 s)and falling(0.29 s)response times upon X-ray irradiation.Detection reliability is also proven by linear response of the X-ray detector,and the X-ray detection limit is 3 mA. 展开更多
关键词 low dark current low detection limit organic photodetector printable X-RAY
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Properties of Activated Carbons from Sugarcane Leaves and Rice Straw Derived Charcoals by Activation at Low Temperature via KMnO_(4)Pre-Oxidation-Hydrolysis
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作者 Sumrit Mopoung Narissara Namkaew and Sasiwan Srikasaem 《Journal of Renewable Materials》 EI CAS 2024年第8期1433-1454,共22页
Activated carbon preparation from sugarcane leaves and rice straw by carbonization(250℃–400℃)and activation at 500℃were studied.The effects of pre-oxidation,hydrolysis of derived charcoals by boiled KMnO4 aqueous ... Activated carbon preparation from sugarcane leaves and rice straw by carbonization(250℃–400℃)and activation at 500℃were studied.The effects of pre-oxidation,hydrolysis of derived charcoals by boiled KMnO4 aqueous solution were evaluated.The derived charcoals products were pretreated using oxidation-hydrolysis with 1–5 wt.%KMnO4 at 100℃and then activated at 500℃.The derived charcoal and activated carbon products were characterized by FTIR,XRD,SEM-EDS and BET.Iodine number and methylene blue number of derived products were also used for the analysis of the products.It was found that fabricated charcoal materials made at 350℃–400℃possess good characteristics with low content of surface functional groups and high carbon content.After pre-oxidation-hydrolysis and activation at 500℃,the resulting derived activated carbon materials from charcoals with 400℃carbonization temperature have high content of oxygen containing surface functional groups such as Mn-O,Si-O,Si-O-Si,C-O,or O-H.In addition,MnO2 accumulated on the surface of the derived activated carbon products.The surface area and pore volume of the activated carbon products have also increased with increasing of KMnO4 concentration from 1 to 3 wt.%and then decreased with 5 wt.%used during activation.Therefore,activated carbon products made by pre-oxidation-hydrolysis with 3 wt.%KMnO4 were used for Fe(Ⅲ)adsorption experiments.It was found that Fe(Ⅲ)adsorption on the activated carbon materials can be fitted with both the Freundlich and the Langmuir models.The calculated maximum Fe(Ⅲ)adsorption capacities of sugarcane leaves derived activated carbon and rice straw derived activated carbon products were 50.00 and 39.37 mg/g,respectively.It was shown that the effect of pre-oxidation-hydrolysis by KMnO4 and activation at 500℃are beneficial for activated carbon preparation with environmentally friendly and low-cost simplified operation. 展开更多
关键词 Activated carbon potassium permanganate pre-oxidation-hydrolysis low carbonization temperature low activation temperature
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Modeling of multiphase flow in low permeability porous media:Effect of wettability and pore structure properties
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作者 Xiangjie Qin Yuxuan Xia +3 位作者 Juncheng Qiao Jiaheng Chen Jianhui Zeng Jianchao Cai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1127-1139,共13页
Multiphase flow in low permeability porous media is involved in numerous energy and environmental applications.However,a complete description of this process is challenging due to the limited modeling scale and the ef... Multiphase flow in low permeability porous media is involved in numerous energy and environmental applications.However,a complete description of this process is challenging due to the limited modeling scale and the effects of complex pore structures and wettability.To address this issue,based on the digital rock of low permeability sandstone,a direct numerical simulation is performed considering the interphase drag and boundary slip to clarify the microscopic water-oil displacement process.In addition,a dual-porosity pore network model(PNM)is constructed to obtain the water-oil relative permeability of the sample.The displacement efficiency as a recovery process is assessed under different wetting and pore structure properties.Results show that microscopic displacement mechanisms explain the corresponding macroscopic relative permeability.The injected water breaks through the outlet earlier with a large mass flow,while thick oil films exist in rough hydrophobic surfaces and poorly connected pores.The variation of water-oil relative permeability is significant,and residual oil saturation is high in the oil-wet system.The flooding is extensive,and the residual oil is trapped in complex pore networks for hydrophilic pore surfaces;thus,water relative permeability is lower in the water-wet system.While the displacement efficiency is the worst in mixed-wetting systems for poor water connectivity.Microporosity negatively correlates with invading oil volume fraction due to strong capillary resistance,and a large microporosity corresponds to low residual oil saturation.This work provides insights into the water-oil flow from different modeling perspectives and helps to optimize the development plan for enhanced recovery. 展开更多
关键词 low permeability porous media Water-oil flow WETTABILITY Pore structures Dual porosity pore network model(PNM) Free surface model
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Development of Superhydrophobic Nano-SiO_(2)and Its Field Application in Low-permeability,High-temperature,and High-salinity Oil Reservoirs
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作者 Qin Bing Gao Min +4 位作者 Lei Xue Zhao Lin Zhu Qizhi Meng Fanbin Jiang Jianlin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期1-14,共14页
In this study,to meet the stringent requirements on the hydrophobicity of nano-SiO_(2)particles for use in depressurization and enhanced injection operations in high-temperature and high-salinity oil reservoirs,second... In this study,to meet the stringent requirements on the hydrophobicity of nano-SiO_(2)particles for use in depressurization and enhanced injection operations in high-temperature and high-salinity oil reservoirs,secondary chemical grafting modification of nano-SiO_(2)is performed using a silane coupling agent to prepare superhydrophobic nano-SiO_(2) particles.Using these superhydrophobic nano-SiO_(2)particles as the core agent,and liquid paraffin or diesel as the dispersion medium,a uniform dispersion of nano-SiO_(2)particles is achieved under high-speed stirring,and a chemically enhanced water injection system with colloidal stability that can be maintained for more than 60 d is successfully developed.Using this system,a field test of depressurization and enhanced injection is carried out on six wells in an oilfield,and the daily oil production level is increased by 11 t.The cumulative increased water injection is 58784 m^(3),the effective rate of the measures was 100%,and the average validity period is 661 d. 展开更多
关键词 nano-SiO_(2)particle hydrophobic modification enhanced injection operation low-grade reservoir low permeability oilfield
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Numerical Simulation of Oil-Water Two-Phase Flow in Low Permeability Tight Reservoirs Based on Weighted Least Squares Meshless Method
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作者 Xin Liu Kai Yan +3 位作者 Bo Fang Xiaoyu Sun Daqiang Feng Li Yin 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1539-1552,共14页
In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering comp... In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering complex boundary shapes.Utilizing radial basis function point interpolation,the method approximates shape functions for unknown functions within the nodal influence domain.The shape functions constructed by the aforementioned meshless interpolation method haveδ-function properties,which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells.Moreover,the meshless method offers greater flexibility and freedom compared to grid cell discretization,making it simpler to discretize complex geometries.A variational principle for the flow control equation group is introduced using a weighted least squares meshless method,and the pressure distribution is solved implicitly.Example results demonstrate that the computational outcomes of the meshless point cloud model,which has a relatively small degree of freedom,are in close agreement with those of the Discrete Fracture Model(DFM)employing refined grid partitioning,with pressure calculation accuracy exceeding 98.2%.Compared to high-resolution grid-based computational methods,the meshless method can achieve a better balance between computational efficiency and accuracy.Additionally,the impact of fracture half-length on the productivity of horizontal wells is discussed.The results indicate that increasing the fracture half-length is an effective strategy for enhancing production from the perspective of cumulative oil production. 展开更多
关键词 Weighted least squares method meshless method numerical simulation of low permeability tight reservoirs oil-water two-phase flow fracture half-length
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Low T3 vs low T3T4 euthyroid sick syndrome in septic shock patients:A prospective observational cohort study
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作者 Mirza Kovacevic Visnja Nesek-Adam +1 位作者 Semir Klokic Ekrema Mujaric 《World Journal of Critical Care Medicine》 2024年第3期53-62,共10页
BACKGROUND Both phases of euthyroid sick syndrome(ESS)are associated with worse prognosis in septic shock patients.Although there are still no indications for supplementation therapy,there is no evidence that both pha... BACKGROUND Both phases of euthyroid sick syndrome(ESS)are associated with worse prognosis in septic shock patients.Although there are still no indications for supplementation therapy,there is no evidence that both phases(initial and prolonged)are adaptive or that only prolonged is maladaptive and requires supplementation.AIM To analyze clinical,hemodynamic and laboratory differences in two groups of septic shock patients with ESS.METHODS A total of 47 septic shock patients with ESS were divided according to values of their thyroid hormones into low T3 and low T3T4 groups.The analysis included demographic data,mortality scores,intensive care unit stay,mechanical ventilation length and 28-day survival and laboratory with hemodynamics.RESULTS The Simplified Acute Physiology Score II score(P=0.029),dobutamine(P=0.003)and epinephrine requirement(P=0.000)and the incidence of renal failure and multiple organ failure(MOF)(P=0.000)were significantly higher for the low T3T4.Hypoalbuminemia(P=0.047),neutrophilia(P=0.038),lymphopenia(P=0.013)and lactatemia(P=0.013)were more pronounced on T2 for the low T3T4 group compared to the low T3 group.Diastolic blood pressure at T0(P=0.017)and T1(P=0.007),as well as mean arterial pressure at T0(P=0.037)and T2(P=0.033)was higher for the low T3 group.CONCLUSION The low T3T4 population is associated with higher frequency of renal insufficiency and MOF,with worse laboratory and hemodynamic parameters.These findings suggest potentially maladaptive changes in the chronic phase of septic shock. 展开更多
关键词 Septic shock Euthyroid sick syndrome low T3 low T3T4 Intensive care unit
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Alkyl dimethyl betaine activates the low-temperature collection capacity of sodium oleate for scheelite 被引量:2
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作者 Xu Wang Zhengquan Zhang +5 位作者 Yanfang Cui Wei Li Congren Yang Hao Song Wenqing Qin Fen Jiao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期71-80,共10页
The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB... The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement.The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12℃. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures. 展开更多
关键词 SCHEELITE BETAINE low temperature synergistic effect dispersion FOAMABILITY
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An ionic liquid-assisted strategy for enhanced anticorrosion of low-energy PEO coatings on magnesium–lithium alloy 被引量:2
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作者 You Zhang Chuping Chen +3 位作者 Haoyue Tian Shuqi Wang Chen Wen Fei Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2380-2396,共17页
A low-energy plasma electrolytic oxidation(LePEO)technique is developed to simultaneously improve energy efficiency and anti-corrosion.Ionic liquids(1-butyl-3-methylimidazole tetrafluoroborate(BmimBF_(4)))as sustainab... A low-energy plasma electrolytic oxidation(LePEO)technique is developed to simultaneously improve energy efficiency and anti-corrosion.Ionic liquids(1-butyl-3-methylimidazole tetrafluoroborate(BmimBF_(4)))as sustainable corrosion inhibitors are chosen to investigate the corrosion inhibition behavior of ionic liquid(ILs)during the LePEO process for LA91 magnesium-lithium(Mg-Li)alloy.Results show that the ionic liquid BmimBF_(4)participates in the LePEO coating formation process,causing an increment in coating thickness and surface roughness.The low conductivity of the ionic liquid is responsible for the voltage and breakdown voltage increases during the LePEO with IL process(LePEO-IL).After adding BmimBF_(4),corrosion current density decreases from 1.159×10^(−4)A·cm^(−2)to 8.143×10^(−6)A·cm^(−2).The impedance modulus increases to 1.048×10^(4)Ω·cm^(−2)and neutral salt spray remains intact for 24 h.The superior corrosion resistance of the LePEO coating assisted by ionic liquid could be mainly attributed to its compact and thick barrier layer and physical absorption of ionic liquid.The ionic liquid-assisted LePEO technique provides a promising approach to reducing energy consumption and improving film performance. 展开更多
关键词 Magnesium-lithium alloy Plasma electrolytic oxidation low energy Ionic liquid Corrosion resistance
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Electrolyte Design for Low‑Temperature Li‑Metal Batteries:Challenges and Prospects 被引量:1
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作者 Siyu Sun Kehan Wang +3 位作者 Zhanglian Hong Mingjia Zhi Kai Zhang Jijian Xu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期365-382,共18页
Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements ... Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases.Herein,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal batteries.Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding.Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared.Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries. 展开更多
关键词 Solid electrolyte interphase Li metal low temperature Electrolyte design BATTERIES
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Revealing the key role of non-solvating diluents for fast-charging and low temperature Li-ion batteries 被引量:1
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作者 Yuping Zhang Siyin Li +8 位作者 Junkai Shi Jiawei Lai Ziyue Zhuang Jingwen Liu Wenming Yang Liang Ma Yue-Peng Cai Jijian Xu Qifeng Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期171-180,共10页
Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based electrolytes due to t... Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based electrolytes due to their slow kinetics,narrow operating temperature and voltage range.Herein,an acetonitrile(AN)-based localized high-concentration electrolyte(LHCE)is proposed to retain liquid state and high ionic conductivity at ultra-low temperatures while possessing high oxidation stability.We originally reveal the excellent thermal shielding effect of non-solvating diluent to prevent the aggregation of Li^(+) solvates as temperature drops,maintaining the merits of fast Li transport and facile desolvation as at room temperature,which bestows the graphite electrode with remarkable low temperature performance(264 mA h g^(-1) at-20 C).Remarkably,an extremely high capacity retention of 97%is achieved for high-voltage high-energy graphite||NCM batteries after 250 cycles at-20 C,and a high capacity of 110 mA h g^(-1)(71%of its room-temperature capacity)is retained at-30°C.The study unveils the key role of the non-solvating diluents and provides instructive guidance in designing electrolytes towards fast-charging and low temperature LIBs. 展开更多
关键词 Li-ion battery Fast-charging low temperature Non-solvating diluent Shielding effect
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Synergistic anionic/zwitterionic mixed surfactant system with high emulsification efficiency for enhanced oil recovery in low permeability reservoirs 被引量:1
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作者 Hai-Rong Wu Rong Tan +6 位作者 Shi-Ping Hong Qiong Zhou Bang-Yu Liu Jia-Wei Chang Tian-Fang Luan Ning Kang Ji-Rui Hou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期936-950,共15页
Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant... Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant sodium alkyl glucosyl hydroxypropyl sulfonate(APGSHS) and zwitterionic surfactant octadecyl betaine(BS-18) is proposed. The performance of APGSHS/BS-18 mixed surfactant system was evaluated in terms of interfacial tension, emulsification capability, emulsion size and distribution, wettability alteration, temperature-resistance and salt-resistance. The emulsification speed was used to evaluate the emulsification ability of surfactant systems, and the results show that mixed surfactant systems can completely emulsify the crude oil into emulsions droplets even under low energy conditions. Meanwhile,the system exhibits good temperature and salt resistance. Finally, the best oil recovery of 25.45% is achieved for low permeability core by the mixed surfactant system with a total concentration of 0.3 wt%while the molar ratio of APGSHS:BS-18 is 4:6. The current study indicates that the anionic/zwitterionic mixed surfactant system can improve the oil flooding efficiency and is potential candidate for application in low permeability reservoirs. 展开更多
关键词 Anionic/zwitterionic mixed surfactant system EMULSIFICATION Synergistic effect low permeability reservoir Enhanced oil recovery
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Accelerated Sequential Deposition Reaction via Crystal Orientation Engineering for Low-Temperature,High-Efficiency Carbon-Electrode CsPbBr_(3) Solar Cells 被引量:1
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作者 Zeyang Zhang Weidong Zhu +10 位作者 Tianjiao Han Tianran Wang Wenming Chai Jiaduo Zhu He Xi Dazheng Chen Gang Lu Peng Dong Jincheng Zhang Chunfu Zhang Yue Hao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期168-175,共8页
Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation en... Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation engineering strategy of PbBr_(2)precursor film to accelerate its reaction with CsBr precursor during two-step sequential deposition of CsPbBr_(3)films.Such a novel strategy is proceeded by adding CsBr species into PbBr_(2)precursor,which can tailor the preferred crystal orientation of PbBr_(2)film from[020]into[031],with CsBr additive staying in the film as CsPb_(2)Br_(5)phase.Theoretical calculations show that the reaction energy barrier of(031)planes of PbBr_(2)with CsBr is lower about 2.28 eV than that of(O2O)planes.Therefore,CsPbBr_(3)films with full coverage,high purity,high crystallinity,micro-sized grains can be obtained at a low temperature of 150℃.Carbon-electrode PSCs with these desired CsPbBr_(3)films yield the record-high efficiency of 10.27%coupled with excellent operation stability.Meanwhile,the 1 cm^(2)area one with the superior efficiency of 8.00%as well as the flexible one with the champion efficiency of 8.27%and excellent mechanical bending characteristics are also achieved. 展开更多
关键词 carbon-electrode perovskite solar cells crystal orientation engineering CsPbBr_(3) low temperature two-step sequential deposition
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Low palladium content CeO_(2)/ZnO composite for acetone sensor with sub-second response prepared by ultrasonic method
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作者 CHEN Xu-jie XING Qiao-ling +2 位作者 TANG Xuan CAI Yong ZHANG Ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2137-2149,共13页
In practical applications,noble metal doping is often used to prepare high performance gas sensors,but more noble metal doping will lead to higher preparation costs.In this study,CeO_(2)/ZnO-Pd with low palladium cont... In practical applications,noble metal doping is often used to prepare high performance gas sensors,but more noble metal doping will lead to higher preparation costs.In this study,CeO_(2)/ZnO-Pd with low palladium content was prepared by ultrasonic method with fast response and high selectivity for acetone sensing.With the same amount of palladium added,the selectivity coefficient of CeO_(2)/ZnO-Pd is 1.88 times higher than that of the stirred sensor.Compared with the pure PdO-doped CeO_(2)/ZnO-PdO material,the content of Pd in CeO_(2)/ZnO-PdO is about 30%of that in CeO_(2)/ZnO-PdO,but the selectivity coefficient for acetone is 2.56 times higher.The CeO_(2)/ZnO-Pd sensor has a higher response(22.54)to 50×10^(−6) acetone at 300℃and the selectivity coefficient is 2.57 times that of the CeO_(2)/ZnO sensor.The sensor has a sub-second response time(0.6 s)and still has a 2.36 response to 330×10^(−9) of acetone.Ultrasonic doping makes Pd particles smaller and increases the contact area with gas.Meanwhile,the composition of n-p-n heterojunction and the synergistic effect of Pd/PdO improve the sensor performance.It shows that ultrasonic Pd doping provides a way to improve the utilization rate of doped metals and prepare highly selective gas sensors. 展开更多
关键词 low palladium sub-second responce ultrasonic method acetone sensor heterojunction
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Arginine promotes seed energy metabolism,increasing wheat seed germination at low temperature
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作者 Jiayu Li Zhiyuan Li +3 位作者 Yangyang Tang Jianke Xiao Vinay Nangia Yang Liu 《The Crop Journal》 SCIE CSCD 2024年第4期1185-1195,共11页
Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly ... Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly important for achieving high and stable wheat yields.In this study,Tongmai 6(insensitive)and Zhengmai 113(sensitive),which have different low-temperature sensitivities during germination were treated with low temperature during germination.The transcriptome,metabolome and physiological data revealed that low temperature decreased the germination rate,downregulated the expression of a large number of genes involved in regulating glycometabolism,and inhibited carbon,nitrogen(especially amino acids)and energy metabolism in the seeds.Arginine content increased at low temperature,and its increase in the low-temperature-tolerant variety was significantly greater than that in the sensitive variety.Arginine priming experiment showed that treatment with an appropriate concentration of arginine improved the seed germination rate.The conversion of starch to soluble sugar significantly increased under exogenous arginine conditions,the content of key metabolites in energy metabolism increased,and the utilization of ATP in the seeds increased.Taken together,arginine priming increased seed germination at low temperature by relieving inhibition of seed carbon and nitrogen metabolism and improving seed energy metabolism. 展开更多
关键词 low temperature Seed germination ARGININE Energy metabolism WHEAT
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Efficient and reversible separation of NH_(3) by deep eutectic solvents with multiple active sites and low viscosities
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作者 Jiayin Zhang Lu Zheng +4 位作者 Siqi Fang Hongwei Zhang Zhenping Cai Kuan Huang Lilong Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期97-105,共9页
The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the environment.In this work,ethanolammonium hydrochloride(EtOHACl)... The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the environment.In this work,ethanolammonium hydrochloride(EtOHACl)and phenol(PhOH)were used to prepare a novel class of deep eutectic solvents(DESs)with multiple active sites and low viscosities.The NH_(3) separation performance of EtOHACl+PhOH DESs was analyzed completely.It is figured out that the NH_(3) absorption rates in EtOHACl+PhOH DESs are very fast.The NH_(3) absorption capacities are very high and reach up to 5.52 and 10.74 mol·kg1 at 11.2 and 100.4 kPa under 298.2 K,respectively.In addition,the EtOHACl+PhOH DESs present highly selective absorption of NH_(3) over N_(2) and H_(2) and good regenerative properties after seven cycles of absorption/desorption.The intrinsic separation mechanism of NH_(3) by EtOHACl+PhOH DESs was further revealed by spectroscopic analysis and quantum chemistry calculations. 展开更多
关键词 SEPARATION Absorption Ionic liquid Deep eutectic solvent Multiple active site low viscosity
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Highly Efficient Broadband Achromatic Microlens Design Based on Low-Dispersion Materials
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作者 Xueqian Wang Chuanbao Liu +7 位作者 Feilou Wang Weijia Luo Chengdong Tao Yuxuan Hou Lijie Qiao Ji Zhou Jingbo Sun Yang Bai 《Engineering》 SCIE EI CAS CSCD 2024年第7期194-200,共7页
Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultracompact configuration;however,they suffer from complex fabrication processes and low focusing efficiency.In this stu... Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultracompact configuration;however,they suffer from complex fabrication processes and low focusing efficiency.In this study,we propose an efficient design method for achromatic microlenses on a wavelength scale using materials with low dispersion,an adequately designed convex surface,and a thickness profile distribution.By taking into account the absolute chromatic aberration,relative focal length shift(FLS),and numerical aperture(NA),microlens with a certain focal length can be realized through our realized map of geometric features.Accordingly,the designed achromatic microlenses with low-dispersion fused silica were fabricated using a focused ion beam,and precise surface profiles were obtained.The fabricated microlenses exhibited a high average focusing efficiency of 65%at visible wavelengths of 410-680 nm and excellent achromatic capability via white light imaging.Moreover,the design exhibited the advantages of being polarization-insensitive and near-diffraction-limited.These results demonstrate the effectiveness of our proposed achromatic microlens design approach,which expands the prospects of miniaturized optics such as virtual and augmented reality,ultracompact microscopes,and biological endoscopy. 展开更多
关键词 Broadband achromatic focusing Metamaterials low dispersion materials Visible wavelength MICROLENSES
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Overview of radar detection methods for low altitude targets in marine environments
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作者 YANG Yong YANG Boyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期1-13,共13页
In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath scattering.The performance... In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath scattering.The performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments. 展开更多
关键词 RADAR sea clutter multipath scattering detection low altitude target
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Debaryomyces hansenii supplementation in low fish meal diets promotes growth,modulates microbiota and enhances intestinal condition in juvenile marine fish
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作者 Ignasi Sanahuja Alberto Ruiz +9 位作者 Joana P.Firmino Felipe E.Reyes-López Juan B.Ortiz-Delgado Eva Vallejos-Vidal Lluis Tort Dariel Tovar-Ramírez Isabel M.Cerezo Miguel A.Moriñigo Carmen Sarasquete Enric Gisbert 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期253-276,共24页
Background The development of a sustainable business model with social acceptance,makes necessary to develop new strategies to guarantee the growth,health,and well-being of farmed animals.Debaryomyces hansenii is a ye... Background The development of a sustainable business model with social acceptance,makes necessary to develop new strategies to guarantee the growth,health,and well-being of farmed animals.Debaryomyces hansenii is a yeast species that can be used as a probiotic in aquaculture due to its capacity to i)promote cell proliferation and differen-tiation,ii)have immunostimulatory effects,iii)modulate gut microbiota,and/or iv)enhance the digestive function.To provide inside into the effects of D.hansenii on juveniles of gilthead seabream(Sparus aurata)condition,we inte-grated the evaluation of the main key performance indicators coupled with the integrative analysis of the intestine condition,through histological and microbiota state,and its transcriptomic profiling.Results After 70 days of a nutritional trial in which a diet with low levels of fishmeal(7%)was supplemented with 1.1%of D.hansenii(17.2×10^(5) CFU),an increase of ca.12%in somatic growth was observed together with an improve-ment in feed conversion in fish fed a yeast-supplemented diet.In terms of intestinal condition,this probiotic modu-lated gut microbiota without affecting the intestine cell organization,whereas an increase in the staining intensity of mucins rich in carboxylated and weakly sulphated glycoconjugates coupled with changes in the affinity for certain lectins were noted in goblet cells.Changes in microbiota were characterized by the reduction in abundance of several groups of Proteobacteria,especially those characterized as opportunistic groups.The microarrays-based transcrip-tomic analysis found 232 differential expressed genes in the anterior-mid intestine of S.aurata,that were mostly related to metabolic,antioxidant,immune,and symbiotic processes.Conclusions Dietary administration of D.hansenii enhanced somatic growth and improved feed efficiency param-eters,results that were coupled to an improvement of intestinal condition as histochemical and transcriptomic tools indicated.This probiotic yeast stimulated host-microbiota interactions without altering the intestinal cell organization nor generating dysbiosis,which demonstrated its safety as a feed additive.At the transcriptomic level,D.hansenii pro-moted metabolic pathways,mainly protein-related,sphingolipid,and thymidylate pathways,in addition to enhance antioxidant-related intestinal mechanisms,and to regulate sentinel immune processes,potentiating the defensive capacity meanwhile maintaining the homeostatic status of the intestine. 展开更多
关键词 Debaryomyces hansenii Intestine condition low fish meal diet MICROBIOTA TRANSCRIPTOMICS Yeast probiotic
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