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AHFO-based soil water content sensing technology considering soil-sensor thermal contact resistance
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作者 Mengya Sun Peng Wu +6 位作者 Bin Shi Jin Liu Jie Liu Juncheng Yao Yipin Lu Yunqiang Wang Xiaoyan Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2715-2731,共17页
The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual applicatio... The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual application of AHFO technology to the water content measurement of in situ soil.However,all existing in situ applications of AHFO technology fail to consider the effect of soilesensor contact quality on water content measurements,limiting potential for the wider application of AHFO technology.To address this issue,the authors propose a method for determining the soilesensor thermal contact resistance based on the principle of an infinite cylindrical heat source.This is then used to establish an AHFO water content measurement technology that considers the thermal contact resistance.The reliability and validity of the new measurement technology are explored through a laboratory test and a field case study,and the spatial-temporal evolution of the soil water content in the case is revealed.The results demonstrate that method for determining the soilesensor thermal contact resistance is highly effective and applicable to all types of soils.This method requires only the moisture content,dry density,and thermal response of the in situ soil to be obtained.In the field case,the measurement error of soil water content between the AHFO method,which takes into account the thermal contact resistance,and the neutron scattering method is only 0.011.The water content of in situ soil exhibits a seasonal variation,with an increase in spring and autumn and a decrease in summer and winter.Furthermore,the response of shallow soils to precipitation and evaporation is significant.These findings contribute to the enhancement of the accuracy of the AHFO technology in the measurement of the water content of in situ soils,thereby facilitating the dissemination and utilization of this technology. 展开更多
关键词 Soil water content Actively heated fiber-optic(AHFO) technology Soilesensor thermal contact resistance RELIABILITY In situ application
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The Impact and Intervention of Handheld Tai Chi Water-Resistance Fitness Ball on Middle-Aged and Elderly Patients with Parkinson’s Disease
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作者 He Huang 《Health》 2024年第4期319-349,共31页
Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionna... Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionnaire on exercise compliance for patients with Parkinson’s disease was developed, and its reliability and validity were tested. Then, a survey was conducted to investigate the current status of exercise compliance among Parkinson’s disease patients, including general information, scoring status, and single and multiple factor analyses of influencing factors [1]. The results of the study show that through qualitative research, the dimensions and item pools of the questionnaire were initially constructed, and the reliability analysis of the questionnaire was conducted through Delphi expert consultation, with favorable results in terms of its reliability and validity [2]. Regarding the current status of exercise compliance among Parkinson’s disease patients, the study found that the level of exercise compliance needs improvement, and there are significant differences in exercise compliance levels among patients under different circumstances. Finally, the research results were discussed and conclusions were drawn. The innovation of this study lies in the development of a questionnaire on exercise compliance for patients with Parkinson’s disease and the preliminary qualitative research and Delphi expert consultation conducted on it, providing new ideas and methods for the study of exercise compliance. However, the study also has limitations as it did not examine the effects of other interventions on Parkinson’s disease, so further research should be conducted [3]. 展开更多
关键词 Parkinson’s Disease Exercise Compliance Tai Chi water resistance Fitness Ball Influencing Factors Intervention Effectiveness
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Ionic liquid derived electrocatalysts for electrochemical water splitting 被引量:1
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作者 Tianhao Li Weihua Hu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期604-622,共19页
Hydrogen production from electrochemical water splitting is a promising strategy to generate green energy,which requires the development of efficient and stable electrocatalysts for the hydrogen evolution reaction and... Hydrogen production from electrochemical water splitting is a promising strategy to generate green energy,which requires the development of efficient and stable electrocatalysts for the hydrogen evolution reaction and the oxygen evolution reaction(HER and OER).Ionic liquids(ILs)or poly(ionic liquids)(PILs),containing heteroatoms,metal-based anions,and various structures,have been frequently involved as precursors to prepare electrocatalysts for water splitting.Moreover,ILs/PILs possess high conductivity,wide electrochemical windows,and high thermal and chemical stability,which can be directly applied in the electrocatalysis process with high durability.In this review,we focus on the studies of ILs/PILs-derived electrocatalysts for HER and OER,where ILs/PILs are applied as heteroatom dopants and metal precursors to prepare catalysts or are directly utilized as the electrocatalysts.Due to those attractive properties,IL/PIL-derived electrocatalysts exhibit excellent performance for electrochemical water splitting.All these accomplishments and developments are systematically summarized and thoughtfully discussed.Then,the overall perspectives for the current challenges and future developments of ILs/PILs-derived electrocatalysts are provided. 展开更多
关键词 Ionic liquid Electrochemical water splitting Hydrogen evolution reaction Oxygen evolution reaction
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Demonstration of irradiation-resistant 4H-SiC based photoelectrochemical water splitting
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作者 Yan Pei Wenhao Geng +4 位作者 Lingbo Xu Can Cui Xiaodong Pi Deren Yang Rong Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第11期74-80,共7页
4H silicon carbide(4H-SiC)has gained a great success in high-power electronics,owing to its advantages of wide bandgap,high breakdown electric field strength,high carrier mobility,and high thermal conductivity.Conside... 4H silicon carbide(4H-SiC)has gained a great success in high-power electronics,owing to its advantages of wide bandgap,high breakdown electric field strength,high carrier mobility,and high thermal conductivity.Considering the high carrier mobility and high stability of 4H-SiC,4H-SiC has great potential in the field of photoelectrochemical(PEC)water splitting.In this work,we demonstrate the irradiation-resistant PEC water splitting based on nanoporous 4H-SiC arrays.A new two-step anodizing approach is adopted to prepare 4H-SiC nanoporous arrays with different porosity,that is,a constant low-voltage etching followed by a pulsed high-voltage etching.The constant-voltage etching and pulsed-voltage etching are adopted to control the diameter of the nanopores and the depth of the nanoporous arrays,respectively.It is found that the nanoporous arrays with medium porosity has the highest PEC current,because of the enhanced light absorption and the optimized transportation of charge carriers along the walls of the nanoporous arrays.The performance of the PEC water splitting of the nanoporous arrays is stable after the electron irradiation with the dose of 800 and 1600 k Gy,which indicates that 4H-SiC nanoporous arrays has great potential in the PEC water splitting under harsh environments. 展开更多
关键词 4H-SIC nanoporous arrays water splitting irradiation resistance photoanodes
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Aircraft Observation and Simulation of the Supercooled Liquid Water Layer in a Warm Conveyor Belt over North China
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作者 Jiefan YANG Fei YAN +3 位作者 Hengchi LEI Shuo JIA Xiaobo DONG Xiangfeng HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期529-544,共16页
This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer... This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer of warm conveyor belts(WCBs).Based on the aircraft data,we found a fine vertical structure within clouds in the WCB and highlighted a 1-2 km thin supercooled liquid water layer with a maximum Liquid Water Content(LWC) exceeding0.5 g kg^(-1) during the vertical aircraft observation.Although the main features of thermodynamic profiles were essentially captured by both modeling schemes,the microphysical quantities exhibited large diversity with different microphysics schemes.The conventional Morrison two-moment scheme showed remarkable agreement with in-situ observations,both in terms of the thermodynamic structure and the supercooled liquid water layer.However,the microphysical structure of the WCB clouds,in terms of LWC and IWC,was not apparent in HUJI fast bin scheme.To reduce such uncertainty,future work may focus on improving the representation of microphysics in bin schemes with in-situ data and using similar assumptions for all schemes to isolate the impact of physics. 展开更多
关键词 warm conveyor belt Microphysical properties supercooled liquid water microphysics schemes
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Fate and Behavior of Tetracycline Resistance Genes in Activated Carbon Adsorption
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作者 Sri Anggreini Alma Rizky Aurellya +1 位作者 Wenqing Li Fusheng Li 《Journal of Water Resource and Protection》 CAS 2024年第1期1-16,共16页
The accessibility of tetracycline resistance gene (tetG) into the pores of activated carbon (AC), as well as the impact of the pore size distribution (PSD) of AC on the uptake capacity of tetG, were investigated using... The accessibility of tetracycline resistance gene (tetG) into the pores of activated carbon (AC), as well as the impact of the pore size distribution (PSD) of AC on the uptake capacity of tetG, were investigated using eight types of AC (four coal-based and four wood-based). AC showed the capability to admit tetG and the average reduction of tetG for coal-based and wood-based ACs at the AC dose of 1 g·L<sup>-1</sup> was 3.12 log and 3.65 log, respectively. The uptake kinetic analysis showed that the uptake of the gene followed the pseudo-second-order kinetics reaction, and the uptake rate constant for the coal-based and wood-based ACs was in the range of 5.97 × 10<sup>-12</sup> - 4.64 × 10<sup>-9</sup> and 7.02 × 10<sup>-11</sup> - 1.59 × 10<sup>-8</sup> copies·mg<sup>-1</sup>·min<sup>-1</sup>, respectively. The uptake capacity analysis by fitting the obtained experiment data with the Freundlich isotherm model indicated that the uptake constant (K<sub>F</sub>) values were 1.71 × 10<sup>3</sup> - 8.00 × 10<sup>9</sup> (copies·g<sup>-1</sup>)<sup>1-1/n</sup> for coal-based ACs and 7.00 × 10<sup>8</sup> - 3.00 × 10<sup>10</sup> (copies·g<sup>-1</sup>)<sup>1-1/n</sup> for wood-based ones. In addition, the correlation analysis between K<sub>F</sub> values and pore volume as well as pore surface at different pore size regions of ACs showed that relatively higher positive correlation was found for pores of 50 - 100 Å, suggesting ACs with more pores in this size region can uptake more tetG. The findings of this study are valuable as reference for optimizing the adsorption process regarding antibiotic resistance-related concerns in drinking water treatment. 展开更多
关键词 Antibiotic resistance Genes ADSORPTION Activated Carbon Drinking water Treatment
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Emerging roles of non-coding RNAs in colorectal cancer oxaliplatin resistance and liquid biopsy potential 被引量:2
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作者 Zheng-Dong Luo Yi-Feng Wang +7 位作者 Yu-Xiao Zhao Long-Chen Yu Tian Li Ying-Jing Fan Shun-Jie Zeng Yan-Li Zhang Yi Zhang Xin Zhang 《World Journal of Gastroenterology》 SCIE CAS 2023年第1期1-18,共18页
Colorectal cancer(CRC)is one of the most common malignancies of the digestive tract,with the annual incidence and mortality increasing consistently.Oxaliplatinbased chemotherapy is a preferred therapeutic regimen for ... Colorectal cancer(CRC)is one of the most common malignancies of the digestive tract,with the annual incidence and mortality increasing consistently.Oxaliplatinbased chemotherapy is a preferred therapeutic regimen for patients with advanced CRC.However,most patients will inevitably develop resistance to oxaliplatin.Many studies have reported that non-coding RNAs(ncRNAs),such as microRNAs,long non-coding RNAs,and circular RNAs,are extensively involved in cancer progression.Moreover,emerging evidence has revealed that ncRNAs mediate chemoresistance to oxaliplatin by transcriptional and post-transcriptional regulation,and by epigenetic modification.In this review,we summarize the mechanisms by which ncRNAs regulate the initiation and development of CRC chemoresistance to oxaliplatin.Furthermore,we investigate the clinical application of ncRNAs as promising biomarkers for liquid CRC biopsy.This review provides new insights into overcoming oxaliplatin resistance in CRC by targeting ncRNAs. 展开更多
关键词 Colorectal cancer Non-coding RNAs OXALIPLATIN resistance liquid biopsy biomarkers
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Physiological Response Mechanism and Drought Resistance Evaluation of Passiflora edulis Sims under Drought Stress
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作者 Binyang Zhao Fengchan Wu +3 位作者 Guojun Cai Peiyu Xi Yulin Guo Anding Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第6期1345-1363,共19页
In order to explore the response mechanism of Passiflora edulis Sims to drought stress,the changes in morpho-logical and physiological traits of Passiflora edulis Sims under different drought conditions were studied.A t... In order to explore the response mechanism of Passiflora edulis Sims to drought stress,the changes in morpho-logical and physiological traits of Passiflora edulis Sims under different drought conditions were studied.A total of 7 germplasm resources of Passiflora edulis Sims were selected and tested under drought stress by the pot culture method under 4 treatment levels:75%–80%(Control,CK)of maximumfield water capacity,55%–60%(Light Drought,LD)of maximumfield water capacity,i.e.,mild drought,40%–45%(Moderate Drought,MD)of max-imumfield water capacity,i.e.,moderate drought and 30%–35%(Severe Drought,SD)of maximumfield water capacity,i.e.,severe drought.On the 40th day of drought treatment,13 indices,including seedling growth mor-phology,physiology,and biochemistry,were measured.The results showed that under drought stress,the height and ground diameter of P.edulis Sims gradually decreased with increasing drought stress,and there were signifi-cant differences in seedling height and ground diameter among the treatments.Drought stress significantly inhib-ited the growth of seven P.edulis Sims varieties.The contents of soluble sugar(SS),soluble protein(SP),proline(Pro),and other substances in P.edulis Sims basically increased with increasing drought stress.With the aggrava-tion of drought stress,the malondialdehyde(MDA)content of P.edulis Sims tended to increase to different degrees,the superoxide dismutase(SOD)activity and peroxidase(POD)activity both tended to increase atfirst and then decrease,and the change in catalase(CAT)activity mostly showed a gradual increasing trend.The con-tents of endogenous hormones in P.edulis Sims significantly differed under different degrees of drought stress.With the aggravation of drought stress,the abscisic acid(ABA)content of P.edulis Sims tended to increase,whereas the contents of gibberellin(GA),indoleacetic acid(IAA),and zeatin nucleoside(ZR)exhibited a down-ward trend.A comprehensive evaluation of the drought resistance of seven P.edulis Sims varieties was conducted based on the principal component analysis method,and the results showed that the drought resistance decreased in the order XH-BL>XH-TWZ>TN1>GH1>ZJ-MT>LP-LZ>DH-JW. 展开更多
关键词 Drought resistance water stress PHYTOHORMONE morphological trait physiological traits
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Experimental Study on the Resistance and Splash Performances of Water Collecting Devices for Mechanical Draft Cooling Towers
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作者 Guoqing Long Guogang Zhang +3 位作者 Qi Zhang Cuilin Zhao Suoying He Fengzhong Sun 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1789-1801,共13页
In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To ex... In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To explore the feasibility of this approach for mechanical draft cooling towers,a small-scale experimental device has been built to study the resistance and splash performances of three U-type water collecting devices(WCDs)for different water flow rates and wind speeds.The experimental results show that within the considered ranges of wind speed and water flow rate,the pressure drop of the different WCDs can vary significantly.The resistance and local splash performances can also be remarkably different.Some recommendations about the most suitable system are provided.Moreover,a regression analysis of the experimental data is conducted,and the resulting fitting formulas for resistance and splash performance of WCD are reported. 展开更多
关键词 Mechanical draft cooling towers water collecting device resistance performance splash performance fitting formulas
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High Water Resistance and Enhanced Mechanical Properties of Bio-Based Waterborne Polyurethane Enabled by in-situ Construction of Interpenetrating Polymer Network
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作者 Henghui Deng Jingyi Lu +5 位作者 Dunsheng Liang Xiaomin Wang Tongyao Wang Weihao Zhang Jing Wang Chaoqun Zhang 《Journal of Renewable Materials》 SCIE EI 2023年第3期1209-1222,共14页
In this study,acrylic acid was used as a neutralizer to prepare bio-based WPU with an interpenetrating polymer network structure by thermally induced free radical emulsion polymerization.The effects of the content of ... In this study,acrylic acid was used as a neutralizer to prepare bio-based WPU with an interpenetrating polymer network structure by thermally induced free radical emulsion polymerization.The effects of the content of acrylic acid on the properties of the resulting waterborne polyurethane-poly(acrylic acid)(WPU-PAA)dispersion and the films were systematically investigated.The results showed that the cross-linking density of the interpenetrating network polymers was increased and the interlocking structure of the soft and hard phase dislocations in the molecular segments of the double networks was tailored with increasing the content of acrylic acid,leading to enhancement of the mechanical properties and water resistance of WPU-PAA films.Notably,with the increase in content of acrylic acid,the tensile strength,Young’s modulus,and toughness of the WPU-PAA-110 film increased by 3 times,and 8 times,and 2.4 times compared with WPU-PAA-80,respectively.The WPU-PAA-100 film showed the best water resistance,and the water absorption rate at 96 h was only 3.27%.This work provided a new design scheme for constructing bio-based WPU materials with excellent properties. 展开更多
关键词 Bio-based waterborne polyurethane interpenetrating polymer network highly water resistance superior mechanical performance
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Research of Oxidation Resistance of PVDF Hollow Fiber Membrane Used in Water Treatment
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作者 曾令强 王志强 陈文清 《Agricultural Science & Technology》 CAS 2010年第9期17-21,共5页
[Objective] The aim was to research the influences of different formulations on oxidation resistance of PVDF hollow fiber membrane.[Method]The immersion precipitation phase inversion method was employed to make castin... [Objective] The aim was to research the influences of different formulations on oxidation resistance of PVDF hollow fiber membrane.[Method]The immersion precipitation phase inversion method was employed to make casting solution with different formulations into hollow fiber membrane.The membrane was immersed in 1% NaClO solution for testing its performance changes.[Result]The membrane made by materials with bigger molecular weight had better oxidation resistance performance;the surfactant tween-80 could increase water flux,but lead to lower rupture intension;Pore-forming agent PEG400 do better than PVP in the oxidation resistance of membrane.[Conclusion]This study will provide a good idea for the development of the PVDF membrane with high oxidation resistance. 展开更多
关键词 water treatment Hollow fiber membrane Oxidation resistance
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Relationship Between Changes of Endogenous Hormone in Sweet Potato Under Water Stress and Variety Drought-resistance 被引量:12
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作者 ZHANG Ming-sheng, XIE Bo and TAN Feng( Agricultural College, Guizhou University, Guiyang 550025 , P. R . China The College of Life Sciences , Southwest Normal University , Chongqing 400715 , P. R . China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第6期626-630,共5页
The IAA, GA3, iPA, ZR and ABA contents in sweet potato leaves under drought conditions were determined by the method of ELISA, and the relationship between these endogenous hormones and drought resistance of different... The IAA, GA3, iPA, ZR and ABA contents in sweet potato leaves under drought conditions were determined by the method of ELISA, and the relationship between these endogenous hormones and drought resistance of different sweet potato varieties were studied. The results showed the IAA, GA3, iPA and ZR contents in sweet potato leaves decreased, but ABA contents increased obviously. The stronger the drought resistance of the variety was, the more IAA, GA3, iPA and ZR contents decreased and the less ABA contents increased. Their relative contents correlated significantly negatively(r were -0.9070, -0.9493, -0.9509, -0.8674 and -0.9117 respectively)to drought-resistability. 展开更多
关键词 Sweet potato water stress Endogenous hormone Drought resistance
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A drought resistance index to select drought resistant plant species based on leaf water potential measurements 被引量:4
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作者 SayedJamaleddin KHAJEDDIN SayedHamid MATINKHAH Zahra JAFARI 《Journal of Arid Land》 SCIE CSCD 2019年第4期623-635,共13页
The water deficit in arid and semi-arid regions is the primary limiting factor for the development of urban greenery and forestation. In addition, planting the species that consume low levels of water is useful in ari... The water deficit in arid and semi-arid regions is the primary limiting factor for the development of urban greenery and forestation. In addition, planting the species that consume low levels of water is useful in arid and semi-arid regions that have poor water management measures. Leaf water potential(Ψ) is a physiological parameter that can be used to identify drought resistance in various species. Indeed, Ψ is one of the most important properties of a plant that can be measured using a pressure chamber. Drought avoiding or drought resistant species have a lower Ψ than plants that use normal or high levels of water. To determine drought resistance of species that are suitable for afforestation in arid urban regions, we evaluated twenty woody species in the Isfahan City, central Iran. The experimental design was random split-split plots with five replications. The species were planted outdoor in plastic pots and then subjected to treatments that consisted of two soil types and five drip irrigation regimes. To evaluate the resistance of each species to drought, we used the Ψ and the number of survived plants to obtain the drought resistance index(DRI). Then, cluster analysis, dendrogram, and similarity index were used to group the species using DRI. Result indicates that the evaluated species were classified into five groups:(1) high water consuming species(DRI>–60 MPa);(2) above normal water consuming species(–60 MPa≥DRI>–90 MPa);(3) normal water consuming species(–90 MPa≥DRI>–120 MPa);(4) semi-drought resistant species(–120 MPa≥DRI>–150 MPa);and(5) drought resistant species(DRI≤–150 MPa). According to the DRI, Salix babylonica L., Populus alba L., and P. nigra L. are high water consuming species, Platanus orientalis L. and Albizia julibrissin Benth are normal water consuming species, and Quercus infectoria Oliv. and Olea europaea L. can be considered as drought resistant species. 展开更多
关键词 DROUGHT resistANT species DROUGHT resistance index forestation leaf water potential water DEFICIT
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Synthesis of a Novel Core-shell Type Acrylic-polyurethane Hybrid Emulsion Containing Siloxane and Fluorine as well as Water and the Oil Resistances of Cured Film 被引量:7
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作者 Jing CHAO Xing Yuan ZHANG Jia Bing DAI Zhen GE Lin Lin FENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1121-1124,共4页
Siliconated polyurethane (Si-PU) was synthesized using isophorone diisocyanate (IPDI), hydroxybutyl-terminated polydimethylsiloxane (PDMS), polytetramethylene ether glycol (PTMG), polypropylene glycol (PPG),... Siliconated polyurethane (Si-PU) was synthesized using isophorone diisocyanate (IPDI), hydroxybutyl-terminated polydimethylsiloxane (PDMS), polytetramethylene ether glycol (PTMG), polypropylene glycol (PPG), 1,6-hexanediol (HDO), dimethylol propionic acid (DMPA) and triethylamine (TEA). Based on butyl acrylate (BA), 2, 2, 2-trifluoroethylmethacrylate (TFEMA) and Si-PU as a seed emulsion, a novel core-shell type acrylic-polyurethane hybrid emulsion, containing siloxane and fluorine (F-Si-PU), was prepared by seeded emulsion polymerization. The contents of siloxane and fluorine were determined according to the feed ratio. Fourier transform infrared spectroscopy (FTIR) was used to identify the chain structures of Si-PU and F-Si-PU. Investigation of transmission electron microscopy (TEM) confirmed the core-shell structure of F-Si-PU emulsion. Measurement results of water contact angle and the swelling ratio in water and n-octane for cured film showed that the water and the oil resistances for F-Si-PU had been significantly improved at a suitable content of fluorine and siloxane. 展开更多
关键词 CORE-SHELL SILOXANE FLUORINE acrylic-polyurethane water and oil resistance.
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INFLUENCE OF SILOXANE CO-SEGMENT LENGTH AND CONTENT OF WATERBORNE POLYSILOXANE-URETHANE COPOLYMERS ON THEIR WATER RESISTANCE,THERMAL STABILITY AND MECHANICAL PROPERTIES 被引量:7
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作者 郑强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期219-229,共11页
A series of stable waterborne polysiloxaneurethane (WPSUR) dispersions were prepared using amino-terminated polydimethylsiloxane (NS), dimethylolpropionic acid (DMPA), castor oil, polypropylene glycol and toluen... A series of stable waterborne polysiloxaneurethane (WPSUR) dispersions were prepared using amino-terminated polydimethylsiloxane (NS), dimethylolpropionic acid (DMPA), castor oil, polypropylene glycol and toluene diisocyanate. Meanwhile, NS with different molecular weights was synthesized and used as the soft co-segment. Effects of types and contents of soft co-segments as well as chain extenders on the thermal degradation and stability for WPSUR films were examined. Results reveal that WPSUR films exhibit excellent water resistance and mechanical properties as compared with pure polyurethane (PU) films, and the NS soft co-segment possesses a remarkable effect on the second stage (stage Ⅱ), while the content of the hard segment is propitious to the initial stage (stage Ⅰ). Moreover, the highest temperature of stage Ⅱ (T2m) for WPSUR films using NS as soft co-segment is 413℃, approximately being 30℃ higher than that of those typical PUs using HDA and APDMS as the chain extenders, respectively. 展开更多
关键词 waterBORNE POLYSILOXANE Polyurethane Castor oil Thermal properties water resistance.
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RESEARCH ON THE WATER-RESISTANCE OF MAGNESIUM OXYCHLORIDE CEMENT——I:THE STABILITY OF THE REACTION PRODUCTS OF MAGNESIUM OXYCHLORIDE CEMENT IN WATER 被引量:9
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作者 张传镁 邓德华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1994年第3期51-59,共9页
In this paper .the change of the crystalline phases in hardened magnesium oxychloride cement (MOC) paste in mater was analyzed by XRD. It was developed that the reaction products 5 phase or 3 phase of MOC are instable... In this paper .the change of the crystalline phases in hardened magnesium oxychloride cement (MOC) paste in mater was analyzed by XRD. It was developed that the reaction products 5 phase or 3 phase of MOC are instable in water and can be changed into Mg(OH)2 by the action of water, which causes the content of 5 phase or 3 phase to be less and less,the content of Mg(OH)2 to be more and more and the strength to be the lower the lower,after hardended MOC paste was immersed in water. The change of 5 pliase and 3 phase into Mg(OH)2 is not a dissolve process, but a hydrolysis process. The hydrolysis products of 5 phase and 3 phase are Mg(OH)2 precipitation and soluble Cl-,AIg+ ions and H2O. The hydrolysis is sponta-neous thermodynamically and its chemical kinatic equation is C = C,,e-k Thus .it is suggested that only by enhancing the stability of 5 phase or 3 phase in water and preventing 5 phase or 3 phase from the hydrolyzing can the water resistance of MOC be improved well. 展开更多
关键词 magnesitt籭. oxychloride cement stability of the reaction products water resistance hydrolysis.
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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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Flow-resistance analysis of nano-confined fluids inspired from liquid nano-lubrication:A review 被引量:3
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作者 Xianzhu Huang Jian Wu +3 位作者 Yudan Zhu Yumeng Zhang Xin Feng Xiaohua Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第11期1552-1562,共11页
How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are... How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are inapplicable to explain the significant differences in the flow resistance of different liquid–solid systems.On the other hand, friction reduction in liquid nano-lubrication has received considerable attention during the past decades. Both fields are exposed to a common scientific issue regarding friction reduction during liquid–solid relative motion at nanoscale. A promising approach to control the flow resistance of nano-confined fluids is to reference the factors affecting liquid nano-lubrication. In this review, two concepts of the friction coefficient derived from fluid flow and tribology were discussed to reveal their intrinsic relations. Recent progress on low or ultra-low friction coefficients in liquid nano-lubrication was summarized based on two situations. Finally, a new strategy was introduced to study the friction coefficient based on analyzing the intermolecular interactions through an atomic force microscope(AFM), which is a cutting-point to build a new model to study flowresistance at nanoscale. 展开更多
关键词 Flow resistance Membrane separation liquid nano-lubrication MODEL Intermolecular interactions AFM
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Hydraulic resistance partitioning between shoot and root system and plant water status of Haloxyolon ammodendron growing at sites of contrasting soil texture 被引量:4
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作者 Xu, GuiQing Li, Yan Zou, Ting 《Journal of Arid Land》 SCIE 2010年第2期98-106,共9页
Hydraulic resistance components and water relations were studied on Haloxyolon ammoden-dron,a small xeric tree,growing at sites significantly differed in soil texture.Soil water content,leaf water potential(ψl),xylem... Hydraulic resistance components and water relations were studied on Haloxyolon ammoden-dron,a small xeric tree,growing at sites significantly differed in soil texture.Soil water content,leaf water potential(ψl),xylem water potential(ψx),root water potential(ψroot),leaf transpiration rate(TR) and stomatal conductance(gs) were measured at the two sites during the growing season of 2005 and 2006.Leaf spe-cific hydraulic resistance(Rplant) during the whole growing season,hydraulic resistance of plants(Rp),shoots(Rshoot) and roots(Rroot) in the August of both years were calculated and expressed on leaf area basis.The results showed the proportion of the hydraulic resistance of the aerial part(Rshoot) to the Rp was the same to the proportion of the hydraulic resistance of the soil part(Rroot) to the Rp,indicating that both parts were equivalent important to plant water hydraulic system from soil to leaf.Positive significant corre-lations were found between Rp and Rroot,suggesting that root hydraulics resistance was a major determinant of plant hydraulic resistance(Rp) and transpiration rate.The integrated effect of stomatal control,hy-draulic regulation and morphology adjustment enabled plants at heavy soil site surviving the extreme water deficit period. 展开更多
关键词 hydraulic architecture leaf water potential TRANSPIRATION hydraulic resistance stomatal conductance hydraulic limitation
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A SRUDY ON CORROSION RESISTANCE OF DIFFERENT MATERIAL IN CONDENSATE WATER FROM A NATURAL GAS PURIFYING STATION 被引量:3
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作者 Y.Z. Luo,D.Y. Yu,Z.M. Xu,Y. Luo,G.T. Qi and J.L. Yang Departent of Chemistry, Huazhong University of Science and Technology, Wuhan 430074,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期936-939,共4页
The corrosion behaviors of different material in the condensate water from the natural gas purifying station were studied by laboratory tests, field tests and measurements of polarization curve. The results showed tha... The corrosion behaviors of different material in the condensate water from the natural gas purifying station were studied by laboratory tests, field tests and measurements of polarization curve. The results showed that hot dipping aluminum steel had a good corrosion resistance to the accompanying gas of crude oil and condensate water in the natural gas purifying station. 展开更多
关键词 condencate water hot dipping aluminum steel corrosion resistance
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