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Correspondence between Susceptibility to SCC of 7050 Aluminum Alloy and Passive Film-induced Stress at Various pH Values 被引量:4
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作者 祁星 宋仁国 +4 位作者 QI Wenjuan JIN Jirong WANG Chao LI Hai SUN Bin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第1期173-178,共6页
The passive film-induced stress and the susceptibility to SCC of 7050 aluminum alloy in 3.5%sodium chloride solution at various pH values were investigated by slow strain rate testing(SSRT) and flowing stress differ... The passive film-induced stress and the susceptibility to SCC of 7050 aluminum alloy in 3.5%sodium chloride solution at various pH values were investigated by slow strain rate testing(SSRT) and flowing stress differential method.The results showed that the passive film-induced stress and the susceptibility to SCC decreased with increasing pH values when pH≤7,while they increased with increasing pH values when pH7.However,the corrosion type was interpreted as exfoliation corrosion when pH=l and 14,and there was no film formed on the surface of the specimens.The whole variation plots of film-induced stress and the SCC susceptibility with pH values were both presented as a valley shape.The symbol and amount of the film-induced stress were related to the compositions of the passive film,which were analyzed using X-ray photoelectron spectroscopy(XPS). 展开更多
关键词 7050 aluminum alloy susceptibility to SCC ph value passive film-induced stress
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Microstructure of nano precursors of La-Mg hydrogen storage alloy synthesized by sol-gel technology at different pH values 被引量:3
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作者 WANG Dahui XIA Jihong ZHANG Sha 《Rare Metals》 SCIE EI CAS CSCD 2012年第5期466-469,共4页
Sol-gel technology was employed to synthesize nanosized precursors of La-Mg hydrogen storage alloy at different pH values (0.5, 1.5, 8.0 and 9.0) of reaction solution. The effect of pH value on microstructure of the n... Sol-gel technology was employed to synthesize nanosized precursors of La-Mg hydrogen storage alloy at different pH values (0.5, 1.5, 8.0 and 9.0) of reaction solution. The effect of pH value on microstructure of the nano precursors of La-Mg hydrogen storage alloy was studied by infrared radiation (IR), thermo-gravimetric and differential thermal analysis (TG/DTA), X-ray diffraction analyzer (XRD) and transmission electron microscopy (TEM). IR results indicate that the chelating agent, citric acid, is not fully ionized, and carboxyl groups are not entirely used to complex metal ions in acidic solutions. The efficiency of complexing metal ions is enhanced in basic solutions. TG/DTA results show that the combustion may take place with low rate of the flame propagation that causes the longer combustion time when pH<1.5. On the contrary, the dry gel synthesized in basic solution combusts at low ignition temperature and combustion reaction is violent; it is easy to form fine particles. XRD and TEM results reveal that the precursor powders are mainly two-phase mixture of La 2 O 3 and MgO. The morphology of the particles is almost flake with the size of ~30 nm when pH is 8.0. 展开更多
关键词 ph value MICROSTRUCTURE nano precursors sol-gel technology
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Effect of Cu and Ni on Growth, Mineral Uptake,Photosynthesis and Enzyme Activities of Chlorella vulgaris at Different pH Values 被引量:3
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作者 P.K.RAI NirupamaMALLICK 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第1期56-67,共12页
A pH dependent reduction in growth, Pigment, ATP content, O,' evolution, carbonfixation, Photosynthetic electron transport system, nutrient uptake (NO,' and NH4+),nitrate reductase, and ATPase activities and i... A pH dependent reduction in growth, Pigment, ATP content, O,' evolution, carbonfixation, Photosynthetic electron transport system, nutrient uptake (NO,' and NH4+),nitrate reductase, and ATPase activities and increase in K+ emux of Chlorella vulgaris wasnoticed following supplementation of Cu and Ni to the culture medium. PS II was foundto be more sensitive to both pH and metals than PS I. Though, nitrate reductase (NR) wasmore sensitive to both PH and metals, the ATPase was however, more sensitive t0 metalsbut less sensitive to acidic pH. Acid PH was found to dst the nutrient (NO,' and NH4+)uptake and nitrate reductase in a non-competitive manner. The inhibition Pnduced by thetest metals alone was of noncompetitive type for NO3' uptake, nitrate reductase andATPase and competitive for NH'+ uptake. Acidity not only inhibited the metabolicvariables directly but also through facilitated uptake of metals and increased membranepermeability. A very low sensitivity of ATPase to acidic pH seems to be resgnsible forthe survival of algae in acid environment. 展开更多
关键词 Mineral Uptake photosynthesis and Enzyme Activities of Chlorella vulgaris at Different ph values Effect of Cu and Ni on Growth ph CU NI
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Comparison of pH Value, TBA Value, Glycogen and Lactic Acid Content in Muscle of Landrace and Yorkshire under Different Storage Time and Conditions 被引量:2
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作者 Zhang Yin Guo Jianfeng +3 位作者 Lin Haichao Wang Jiying Wang Cheng Wu Ying 《Animal Husbandry and Feed Science》 CAS 2017年第3期145-150,164,共7页
In order to assess the meat quality under different storage time and conditions, the pH value, TBA value, glycogen and lactic acid content in muscle of Landrace and Yorkshire were measured. The results showed that wit... In order to assess the meat quality under different storage time and conditions, the pH value, TBA value, glycogen and lactic acid content in muscle of Landrace and Yorkshire were measured. The results showed that within 10 h post slaughtering, post slaughtering time had extremely significant influence on pH value and lactic acid content of Landrace, but had no significant influence on glycogen content and TBA value. On the other hand, post slaughtering time had extremely significant influence on pH value of Yorkshire, but had no significant influence on glycogen, lactic acid content and TBA value. The pH values of Yorkshire at 3, 5 and 10 h post slaughtering were 5.21% ( P 〈 0.01 ), 5.64% ( P 〈 0.05 ) and 5.59% ( P 〈 0.05 ) higher than those of Landrace, respectively ; the lactic acid content in muscle of Landrace at 10 h post slaughtering was 56.04% (P 〈0.05) higher than that of Yorkshire; the TBA value in muscle of Yorkshire at 10 h post slaughtering was 89. 19% (P 〈 0.01 ) higher than that of Landrace; there was no significant difference in glycogen content between Yorkshire and Landrace. When pork stored at 4℃, storage time had no significant influence on pH value and glycogen content in muscle of Landrace, but had significant influence on drip loss, lactic acid content and TBA value ; storage time had no significant influence on pH value, glycogen content and TBA value in muscle of Yorkshire, but extremely significant influence on drip loss and significant influence on lactic acid content. The pH value in muscle of Yorkshire at 24 h post storage at 4℃ was 6.56% (P 〈0.05) higher than that of Landrace; the glycogen contents in muscle of Landrace at 24, 48, 72, 96, 120 and 144 h post storage at 4℃ were 84.90% (P〈0.05),78.40% (P〈0.01), 101.87% (P〈0.05), 83.80% (P〈0.05), 83.59% (P〈 0.05)and67.25% (P〈0.01)higher than those of York-shire, respectively; the drip loss of Landrace at 72 h post storage and TBA value at 144 h post storage were 55.70% ( P 〈 0.05 ) and 141.33 % ( P 〈 0.01 ) higher than those of Yorkshire, respectively; there was no significant difference in glycogen content between Yorkshire and Landrace. When pork stored at -20℃, storage time had significant influence on TBA value in muscle of Landrace, but had no significant influence on pH value, thawing water loss rate, glycogen and lactic acid content; storage time had no significant impact on pH value, thawing water loss rate, glycogen content and TBA value in muscle of Yorkshire, and had significant influence on lactic acid content. The pH value in muscle of Yorkshire at 24 h post storage at - 20℃ was 5.43 % ( P 〈 0.05 ) higher than that of I.andrace ; the glycogen contents in muscle of Landrace at 24, 48, 72, 96, 120 h post storage at - 20℃ were 85.08% ( P 〈0. 05 ), 108.66% ( P 〈 0.01 ), 72.69% ( P 〈 0.05 ), 90.31% ( P 〈 0.01 ), 70.38% ( P 〉 0.05 ) higher than those of Yorkshire, respectively ; the thawing water loss rates of Landrace at 24 and 72 h were 160.14% ( P 〈 0.05 ) and 74.32% ( P 〈 0.05 ) higher than those of Yorkshire, respectively ; there was no significant difference in lactic acid content and TBA value at the same time point between Yorkshire and Landrace. 展开更多
关键词 PORK Storage time and conditions ph value GLYCOGEN Lactic acid content TBA value
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Electrochemical Behavior of Steel Bar in Electrolytes:Influence of pH Value and Cations 被引量:1
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作者 濮琦 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第6期1133-1136,共4页
Steel bar corrosion on electrolytes and the influence of cation were investigated. Three electrolytes of Ca(OH)2, NaOH and KOH with pH levels of 12.5, 11.5, 10.5, 9.5, 8.5 were prepared, meanwhile, the methods of fr... Steel bar corrosion on electrolytes and the influence of cation were investigated. Three electrolytes of Ca(OH)2, NaOH and KOH with pH levels of 12.5, 11.5, 10.5, 9.5, 8.5 were prepared, meanwhile, the methods of free corrosion potential and electrochemical impedance spectra (EIS) were used to evaluate the influence of cations on the depassivation of the steel bar in electrolytes. The experimental results indicate that the initial corrosion pH value of the steel bar is influenced by the cation in electrolyte and the influence of K+ in electrolyte is the most remarkable, followed by Na+ and Ca2+. The initial corrosion pH values are 10.5 in KOH electrolyte, 9.5 in NaOH electrolyte and lower than 8.5 in Ca(OH)2 electrolyte. 展开更多
关键词 steel bar corrosion CATION ph value
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Relationship Between pH Value and Physical and Chemical Properties of Tobacco-growing Soil 被引量:1
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作者 Yunfei CHEN Jiye QIANG Ailian OUYANG 《Agricultural Biotechnology》 CAS 2021年第2期99-101,106,共4页
[Objectives]This study was conducted to understand the relationship between soil pH and soil physical and chemical properties during tobacco planting.[Methods]Through a field experiment,the pH value of tobacco-growing... [Objectives]This study was conducted to understand the relationship between soil pH and soil physical and chemical properties during tobacco planting.[Methods]Through a field experiment,the pH value of tobacco-growing soil,the contents of mineral nutrients(ammonium nitrogen,alkali-hydrolyzable nitrogen,available potassium,available phosphorus),soil bulk density and porosity were investigated.[Results]The pH value of the soil after tobacco planting increased,and the contents of ammonium nitrogen,alkali-hydrolyzable nitrogen,and available potassium were closely related to the change of pH value.The bulk density of the tobacco-planting soil decreased and the porosity increased.Planting flue-cured tobacco had certain impacts on soil pH,soil bulk density and other physical and chemical properties.[Conclusions]This study provides a theoretical basis for the investigation of the fertilization laws in the process of tobacco planting and the selection of subsequent crops. 展开更多
关键词 Tobacco growing soil ph value Mineral nutrients Bulk density POROSITY
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Effects of Straw and Biochar Returned to the Soil on Soil Physical Properties and pH Value in Cold Rice Region 被引量:1
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作者 Yuefeng CUI Hongru SHI +5 位作者 Aonan GUO Guocai SUN Guiyan WANG Jian WANG Wenjia HUANG Tiegang LU 《Asian Agricultural Research》 2021年第2期27-32,共6页
[Objectives]In order to explore the feasibility of using straw and biochar returned to the soil to improve soil physical properties and pH value in cold rice regions of China.[Methods]the effects of straw directly ret... [Objectives]In order to explore the feasibility of using straw and biochar returned to the soil to improve soil physical properties and pH value in cold rice regions of China.[Methods]the effects of straw directly returned to the soil and charred straw(biochar)returned to the soil on soil bulk density,porosity,temperature and pH value of cold paddy soil were studied in this paper.[Results]The results showed that compared with conventional production,straw(6 t/ha),a small amount of biochar(2 t/ha)and a large amount of biochar(40 t/ha)returned to the soil reduced paddy soil bulk density at different growth stages by 6.02%-11.86%,2.69%-6.67%and 8.58%-11.32%,respectively,increased total porosity by 7.41%-14.93%,3.19%-8.38%and 9.81%-14.27%,respectively,and increased aeration porosity by 22.28%-192.11%,17.80%-92.11%and 52.44%-157.11%,respectively.Straw and a small amount of biochar returned to the soil had no significant effect on soil temperature and pH value of paddy field,but a large amount of biochar returned to the soil could significantly increase soil temperature by 5.13%-8.79%and pH value by 3.15%-5.96%in the later stage of rice growth.[Conclusions]The straw and biochar returned to the soil could reduce soil bulk density,increase total porosity and aeration porosity,and only a large amount of biochar returned to the soil could significantly increase soil temperature and pH value. 展开更多
关键词 STRAW BIOCHAR Cold rice region Soil physical properties Soil ph value
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Capacitance Characterization of the Effect of pH Value on the Self-assembled Monolayers of Octadecanethiol
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作者 KeQiangDING QingFeiWANG +1 位作者 RuTingTONG HuiBoSHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第4期411-412,共2页
In this paper, the membrane capacitance (Cm), which was obtained from the electro- chemical impedance spectroscopy (EIS) method, was used to characterize the effect of pH value on the self-assembled monolayers (SAMs) ... In this paper, the membrane capacitance (Cm), which was obtained from the electro- chemical impedance spectroscopy (EIS) method, was used to characterize the effect of pH value on the self-assembled monolayers (SAMs) of octadecanethiol(18SH) for the first time. The results not only strongly proved that inorganic ions could penetrate the SAMs of 18SH, but also ascertained that SAMs of 18SH were not an absolute of free of ion-penetration. Verifying the existence of pin-holes in the octadecanethiol SAMs was the main contribution of this paper, which coincided with the former conjecture very well. 展开更多
关键词 Octadecanethiol SAMS EFFECT ph value capacitance characterization.
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Effect of pH Value on Nano-Al_2O_3/Ni+Co Gradient Bionic Composite Coating by Electrodeposition
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作者 刘燕 任露泉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第S1期50-53,共4页
The metal and nano-ceramic composite coatings were formed on gray cast iron surface by electrodepositon method.The Ni-Co was used as metal matrix,and the nano-Al2O3 was chosen as second-phase particulates.The gradient... The metal and nano-ceramic composite coatings were formed on gray cast iron surface by electrodepositon method.The Ni-Co was used as metal matrix,and the nano-Al2O3 was chosen as second-phase particulates.The gradient structure of biology material was the model to avoid bad interface bonding and stress distribution,therefore the gradient composite coating was prepared.The morphology of composite coatings was flatter and the microstructure was more com-pact than the pure Ni-Co coatings.Effect of pH value on surface morphology was analyzed,which some microcracks appeared when pH value was greater than 5.The content of codeposition na-no-Al2O3 reached a maximum value at pH value of 3-4,at the same time the properties including mi-crohardness and wear-resistance were analyzed.The result indicated that the mirohardness reached a maximum value and the wear loss volume was less at pH value 3-4. 展开更多
关键词 ph value ELECTRODEPOSITION gradient composite coating microstructure PROPERTY
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Analyzing pH value, energy and phospholipid metabolism of various cerebral tumors and normal brain tissue with ^(31)P magnetic resonance spectroscopy
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作者 Wei Tan Guangyao Wu Junmo Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第3期248-252,共5页
BACKGROUND: ^31p magnetic resonance spectroscopy (^31p MRS) can be used to non-injuredly and dynamicly detect vadous metabolites including phosphorus in organis and reflect changes of phospholipid metabolism and en... BACKGROUND: ^31p magnetic resonance spectroscopy (^31p MRS) can be used to non-injuredly and dynamicly detect vadous metabolites including phosphorus in organis and reflect changes of phospholipid metabolism and energy metabolism in tissue and pH value in cells. OBJECTIVE: To observe changes of pH value, phospholipid metabolism and energy metabolism of various cerebral tumors and normal brain tissue with sip MRS. DESIGN: Semi-quantitative contrast observation PARTICIPANTS : A total of 44 patients with cerebral tumor diagnosed with surgery operation were selected from the Department of Magnetic Resonance, Central South Hospital, Wuhan University from September 2004 to June 2006. All the subjects had complete sip MRS data before steroid and operation. Among them, 16 patients had glioma of grade Ⅱ-Ⅲ, 12 spongioblastoma and 16 meningioma. The mean age was (45±6) years. Another 36 subjects without focus on cerebral MRI were regarded as normal group, including 19 males and 18 females, and the mean age was (41±4) years. Included subjects were consent. METHODS: Eclipse1.5T MRS (Philips Company) was used to collect wave spectrum; jMRUI(1.3) was used to analyze expenmental data and calculate pH value in voxel and ratios of phosphocreatine (PCr)/inorganic phosphate (Pi), PCr/phosphodiesterase (PDE) and phosphomonoesterase (PME)/β-adenosine triphosphate (β-ATP) of vadous metabolites. ^31p MRS results were compared with t test between tumor patients and normal subjects. MAIN OUTCOME MEASURES: Changes of phospholipid metabolism (PME./PDE), energy metabolism (PCr/ATP) and pH value of various cerebral tumors and normal brain tissues. RESULTS : A total of 44 cases with cerebral tumor and 36 normal subjects were involved in the final analysis. pH value and semi-quantitative measurements of normal brain tissues and various cerebral tumors: ① pH value at top occipital region and temple occipital region of normal brain tissue was 7.04 ±0.02; PCr/β-ATP was 1.51 ±0.03; PCr/Pi was 2.85±0.20; PDE/β-ATP was 2.70±0.40; PME/β-ATP was 1.01 ±0.03. Giioma of grade Ⅱ - Ⅲ : Tumor tissue was alkalized. The pH value was 7.09±0.01, which was higher than that in normal group (t=-1.823, P 〈 0.05); PCr/β-ATP, PME/β-ATP and PCr/ Pi were 1.50±0.04, 1.04±0.07 and 2.49±0.21, respectively, which was close to that in normal group (P 〉 0.05); PDE/β-ATP was 1.73±0.20, which was lower than that in normal group (t=-2.168, P 〈 0.05). ③ Spongioblastoma: Tumor tissue was alkalized. The pH value was 7.12±0.02, which was higher than that in normal group (t=-2.170, P 〈 0.05); PCr/β-ATP and PCr/Pi were 1.48±0.05 and 2.39±0.23, respectively, which was lower than that in normal group, but the difference was not significant (P 〉 0.05); PDE/β-ATP was 1.61±0.25, which was lower than that in normal group (t=-3.582, P 〈 0.01); PME/β-ATP was 1.64±0.05, which was higher than that in normal group (t=-3.930, P 〈 0.01). ④ Meningioma: Tumor tissue was alkalized. The pH value was 7.16±0.03, which was higher than that in normal group (t=-2.978, P 〈 0.01); PCr/β-ATP, PCr/Pi and PDE/β-ATP were 0.46±0.04, 1.08±0.16 and 0.82±0.10, respectively, which was lower than that in normal group (t=-3.132, 3.983, 3.985, P 〉 0.01); PME/β-ATP was 2.05±0.03, which was higher than that in normal group (t=-3.007, P〈 0.01). CONCLUSION: ^31p MRS can provide informations about pH value of cerebral tumor, phospholipid metabolism and energy metabolism. Changes of pH value, PCr, PME and PDE can reflect metabolic characteristics of various cerebral tumors. 展开更多
关键词 P magnetic resonance spectroscopy Analyzing ph value PDE ph
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X-ray absorption near-edge structure study on the configuration of Cu2+/histidine complexes at different pH values
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作者 于梅娟 王宇 徐伟 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期474-478,共5页
The local configurations around metal ions in metalloproteins are of great significance for understanding their biolog- ical functions. Cu2+/histidine (His) is a typical complex existing in many metalloproteins and... The local configurations around metal ions in metalloproteins are of great significance for understanding their biolog- ical functions. Cu2+/histidine (His) is a typical complex existing in many metalloproteins and plays an important role in lots of physiological functions. The three-dimensional (3D) structural configurations of Cu2+/His complexes at different pH values (2.5, 6.5, and 8.5) are quantitatively determined by x-ray absorption near-edge structure (XANES). Generally Cu2+/His complex keeps an octahedral configuration consisting of oxygen atoms from water molecules and oxygen or nitrogen atoms from histidine molecules coordinated around Cu2+. It is proved in this work that the oxygen atoms from water molecules, when increasing the pH value from acid to basic value, are gradually substituted by the Ocarboxy1, Nam, and Nim from hisitidine molecules. Furthermore, the symmetries of Cu2+/His complexes at pH 6.5 and pH 8.5 are found to be lower than at pH 2.5. 展开更多
关键词 x-ray absorption near-edge structure Cu2+/His ph values CONFIGURATION
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pH value monitoring during human albumin purification with near infrared spectroscopy and chemometrics
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作者 Qiaofeng Sun Zhongyu Sun +6 位作者 Fei Wang Lian Li Ronghua Liu Lei Nie Jiayue Wang Mingyu Wang Hengchang Zang 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2018年第3期28-37,共10页
Human albumin(HA)is a very important blood product which requires strict quality controlstrategy.Acid precipitation is a key step which has a great effect on the quality of final product.Therefore,a new method based o... Human albumin(HA)is a very important blood product which requires strict quality controlstrategy.Acid precipitation is a key step which has a great effect on the quality of final product.Therefore,a new method based on quality by design(QbD)was proposed to investigate thefeasibility of realizing online quality control with the help of near infrared spectroscopy(NIRS)and chemometrics.The pH value is the critical process parameter(CPP)in acid precipitationprocess,which is used as the end-point indicator.Six batches,a total of 74 samples of acidprecipitation process,were simulated in our lab.Four batches were selected randomly as cali-bration set and remaining two batches as validation set.Then,the analysis based on materialinformation and three dfferent variable selection methods,including interval partial least squaresregression(iPLS),competitive adaptive reweighted sampling(CARS)and correlation coeficient(CC)were compared for eliminating irrelevant variables,Fimally,iPLS was used for variablesselection.The quantitative model was built up by partial least squares regression(PLSR).Thevalues of determination coeficients(R^(2)_(C) and R^(2)_(P)),root mean squares error of prediction(RMSEP),root mean squares error of calibration(RMSEC)and root mean squared error of crossvalidation(RMSECV)were 0.969,0.953,0.0496,0.0695 and 0.0826,respectively.The paired t test and repeatability test showed that the model had good prediction ability and stability.The results indicated that PLSR model could give accurate measurement of the pH value. 展开更多
关键词 Near infrared spectroscopy human albumin acid precipition proces ph value CHEMOMETRICS
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Effect of pH Value on the Micro-structures and Optical Properties of Nano-crystalline CuInS_2 by Solvothermal Method
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作者 冯嘉敏 韩建军 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第3期399-402,共4页
Copper indium disulfide(CuInS2) nano-particles were synthesized by solvothermal method at 150 ℃ using copper(?) chloride,indium(Ш) chloride,thiourea and ethanol as raw materials,and characterized by X-ray dif... Copper indium disulfide(CuInS2) nano-particles were synthesized by solvothermal method at 150 ℃ using copper(?) chloride,indium(Ш) chloride,thiourea and ethanol as raw materials,and characterized by X-ray diffraction(XRD),field-emission scanning electron microscope(FESEM),and UV-Vis spectra.The effects of pH value on its micro-structures and optical properties were investigated.The results show that,with the pH value increasing,the particle size of the nano-crystalline CuInS2 increases,and its band gap becomes narrower under alkaline condition.The band gaps of CuInS2 nano-particles are from 1.52 eV to 1.93 eV,which makes them promising candidates as absorber materials for photovoltaic applications. 展开更多
关键词 solvothermal method CuInS2 nano-particles ph value
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ZnO Additive Boosts Charging Speed and Cycling Stability of Electrolytic Zn–Mn Batteries
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作者 Jin Wu Yang Tang +6 位作者 Haohang Xu Guandie Ma Jinhong Jiang Changpeng Xian Maowen Xu Shu‑Juan Bao Hao Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期293-304,共12页
Electrolytic aqueous zinc-manganese(Zn–Mn) batteries have the advantage of high discharge voltage and high capacity due to two-electron reactions. However, the pitfall of electrolytic Zn–Mn batteries is the sluggish... Electrolytic aqueous zinc-manganese(Zn–Mn) batteries have the advantage of high discharge voltage and high capacity due to two-electron reactions. However, the pitfall of electrolytic Zn–Mn batteries is the sluggish deposition reaction kinetics of manganese oxide during the charge process and short cycle life. We show that, incorporating ZnO electrolyte additive can form a neutral and highly viscous gel-like electrolyte and render a new form of electrolytic Zn–Mn batteries with significantly improved charging capabilities. Specifically, the ZnO gel-like electrolyte activates the zinc sulfate hydroxide hydrate assisted Mn^(2+) deposition reaction and induces phase and structure change of the deposited manganese oxide(Zn_(2)Mn_(3)O_8·H_(2)O nanorods array), resulting in a significant enhancement of the charge capability and discharge efficiency. The charge capacity increases to 2.5 mAh cm^(-2) after 1 h constant-voltage charging at 2.0 V vs. Zn/Zn^(2+), and the capacity can retain for up to 2000 cycles with negligible attenuation. This research lays the foundation for the advancement of electrolytic Zn–Mn batteries with enhanced charging capability. 展开更多
关键词 Electrolytic aqueous zinc-manganese batteries Electrolyte ph value ZnO electrolyte additive Fast constant-voltage charging ability
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Effect of humic substances on the precipitation of calcium phosphate 被引量:11
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作者 SONG Yong-hui Hermann H. HAHN +1 位作者 Erhard HOFFMANN Peter G. WEIDLER 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期852-857,共6页
For phosphorus (P) recovery from wastewater, the effect of humic substances (HS) on the precipitation of calcium phosphate was studied. Batch experiments of calcium phosphate precipitation were undertaken with syn... For phosphorus (P) recovery from wastewater, the effect of humic substances (HS) on the precipitation of calcium phosphate was studied. Batch experiments of calcium phosphate precipitation were undertaken with synthetic water that contained 20 mg/L phosphate (as P) and 20 mg/L HS (as dissolved organic carbon, DOC) at a constant pH value in the range of 8.0-10.0. The concentration variations of phosphate, calcium (Ca) and HS were measured in the precipitation process; the crystalline state and compositions of the precipitates were analysed by powder X-ray diffraction (XRD) and chemical methods, respectively. It showed that at solution pH 8.0, the precipitation rate and removal efficiency of phosphate were greatly reduced by HS, but at solution pH ≥9.0, the effect of HS was very small. The Ca consumption for the precipitation of phosphate increased when HS was added; HS was also removed from solution with the precipitation of calcium phosphate. At solution pH 8.0 and HS concentrations ≤3.5 mg/L, and at pH ≥ 9.0 and HS concentrations ≤ 10 mg/L, the final precipitates were proved to be hydroxyapatite (HAP) by XRD. The increases of solution pH value and initial Ca/P ratio helped reduce the influence of HS on the precipitation of phosphate. 展开更多
关键词 calcium phosphate phosphorus recovery PRECIPITATION humic substances initial CaJP ratio solution ph value
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Physical and Chemical Transformation of Hydroxyapatite Nanoparticles in Aqueous Sol after Preparation and in vitro 被引量:3
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作者 I W Bauer 李世普 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期283-286,共4页
The co-precipitation method followed by ultrasound and heat treatment is a common way to prepare below 100 nm sized hydroxyapathe nanoparticles for biomedical studies and applications. The size and pH value of the ob... The co-precipitation method followed by ultrasound and heat treatment is a common way to prepare below 100 nm sized hydroxyapathe nanoparticles for biomedical studies and applications. The size and pH value of the obtained calcium phosphate nanoparticles in aqueous sol have a strong impact on the interactions with cells and tissue. The physical and chemical properties of material samples for in vitro and in vivo studies are often assumed to remain constant from the time after fabrication to the actual use. Only little attention is paid to eventual changes of the material over time or due to the different in vitro conditions. In this study, the physical and chemical transformation of calcium phosphate nanoparticles after preparation and in vitro was investigated. As the result showed, dispersed nano sized amorphons calcium phosphate precipitation as well as crystallized hydroxyapathe nanoparticles continue to crystallize even when kept at 4℃ leading to declining pH values and particle sizes. Due to the pH buffer in the medium the pH value of the cell culture remained stable after adding 20% nanoparticle sol in vitro. However, hydroxyapathe nanoparticles immediately became unstable in the presents of cell culture medium. The resulting loose agglomerations showed a size of above 500 nm. 展开更多
关键词 Nanoparticles HYDROXYAPATITE CRYSTALLIZATION ph value particle size in vitro
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Historical simulation and twenty-first century prediction of oceanic CO_2 sink and pH change 被引量:3
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作者 BAO Ying QIAO Fangli SONG Zhenya 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第5期87-97,共11页
A global ocean carbon cycle model based on the ocean general circulation model POP and the improved biogeochemical model OCMIP-2 is employed to simulate carbon cycle processes under the historically observed atmospher... A global ocean carbon cycle model based on the ocean general circulation model POP and the improved biogeochemical model OCMIP-2 is employed to simulate carbon cycle processes under the historically observed atmospheric CO 2 concentration and different future scenarios (called Rep- resentative Concentration Pathways, or RCPs). The RCPs in this paper follow the design of Inter- governmental Panel on Climate Change (IPCC) for the Fifth Assessment Report (AR5). The model results show that the ocean absorbs CO 2 from atmosphere and the absorbability will continue in the 21st century under the four RCPs. The net air-sea CO 2 flux increased during the historical time and reached 1.87 Pg/a (calculated by carbon) in 2005; however, it would reach peak and then decrease in the 21st century. The ocean absorbs CO 2 mainly in the mid latitude, and releases CO 2 in the equator area. However, in the Antarctic Circumpolar Current (ACC) area the ocean would change from source to sink under the rising CO 2 concentration, including RCP4.5, RCP6.0, and RCP8.5. In 2100, the anthropogenic carbon would be transported to the 40 S in the Atlantic Ocean by the North Atlantic Deep Water (NADW), and also be transported to the north by the Antarctic Bottom Water (AABW) along the Antarctic continent in the Atlantic and Pacific oceans. The ocean pH value is also simulated by the model. The pH decreased by 0.1 after the industrial revolution, and would continue to decrease in the 21st century. For the highest concentration sce- nario of RCP8.5, the global averaged pH would decrease by 0.43 to reach 7.73 due to the absorption of CO 2 from atmosphere. 展开更多
关键词 ocean carbon cycle model air-sea CO 2 flux anthropogenic carbon ph value
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A new electroplated Ir/Ir(OH)_x pH electrode and its application in the coastal areas of Newport Harbor, California 被引量:2
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作者 ZHANG Xiao YE Ying +5 位作者 KAN Yating HUANG Yuanfeng JIA Jianjun ZHAO Yue CHEN Chen-Tung Arthur QIN Huawei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第5期99-104,共6页
Resulting from the rising levels of atmospheric carbon, ocean acidification has become a global problem. It has significant impacts on the development, survival, growth and physiology of marine organisms. Therefore, a... Resulting from the rising levels of atmospheric carbon, ocean acidification has become a global problem. It has significant impacts on the development, survival, growth and physiology of marine organisms. Therefore, a high- precision sensor is urgently needed to measure the pH of sea-water. Iridium wire with a diameter of 0.25 mm is used as the substrate, and an Ir/Ir(OH)x pH electrode is prepared by a one-step electrochemical method in a LiOH solution at the room temperature. A scanning electron microscope (SEM) observation reveals that it is coated with nanoscale particles. In laboratory tests, the electrode exhibits a very promising pH response, with an ideal Nernst slope (56.14-59.52), fast response, good stability and long fife-span in tested pH buffer solutions. For a sea trial, four pH electrodes and one Ag/AgC1 reference electrode are integrated with a self-made chemical sensor, and a profile detection of nearly 70 m is implemented near Newport Harbor, California on August 3, 2015. The results reflect that the pH value measured by the sensor is very close to the data given by Sea-Bird 911 plus CTD, with a difference value ranging from 0.000 075 to 0.064 719. And the sensor shows a better data matching degree in 0-40 m water depth. In addition, the high precision and accuracy of the sensor make it possible to use in the ocean observation field. 展开更多
关键词 Ir/Ir(OH)x electrode ph value ELECTROPLATING Newport Harbor California
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Variables Affecting the pH Measurement of Cement Mortars 被引量:1
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作者 PAYAM Shafigh SUMRA Yousuf ZAINAH Ibrahim 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2021年第5期689-696,共8页
A quantitative pH measuring method has been used to measure the pH of pure and blended cement mortars.The blended cement mortars incorporating supplementary cementitious materials(SCMs)such as fly ash(FA),ground granu... A quantitative pH measuring method has been used to measure the pH of pure and blended cement mortars.The blended cement mortars incorporating supplementary cementitious materials(SCMs)such as fly ash(FA),ground granulated ballast furnace slag(GGBFS)and palm oil fuel ash(POFA)were used.Moreover,different variables affecting the pH values of CBMs such as temperature of sample solution,quantity of sample powder,dilution ratio and temporary storage of sample during pH measuring process have been studied for all cement mortars. 展开更多
关键词 MORTAR cementitious materials ph value dilution ratio TEMPERATURE
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Effects of Different Heavy Crude Oil Fractions on the Stability of Oil-in-Water Emulsion——Ⅲ. Effects of pH on the interfacial properties of heavy crude functional fractions and water system 被引量:1
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作者 FanWeiyu NanGuozhi LiShuiping SongYuanming 《Petroleum Science》 SCIE CAS CSCD 2005年第2期103-106,111,共5页
In this paper, effects of pH on the interfacial properties of heavy crude functional fractions and water system are investigated. The influence of pH on π-A isotherms of acid fraction, basic fraction, amphoteric frac... In this paper, effects of pH on the interfacial properties of heavy crude functional fractions and water system are investigated. The influence of pH on π-A isotherms of acid fraction, basic fraction, amphoteric fraction and asphaltene is great. The interfacial pressure of fractions increases in strongly basic conditions. The ζ (-80mv) of acid fraction is the largest under basic conditions (pH=11-12), with the result to show that the interfacial activity of the acid fraction is superior to that of other fractions. The results of model emulsions show that strongly basic conolition (pH≥11) is beneficial to oil-in- water emulsion stability. The interfacial activity of acid fraction and asphaltene is superior to that of other crude fractions. 展开更多
关键词 ph value stable factors of emulsion interfacial properties
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