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...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 La2O3 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
The Co-based catalysts were prepared with different cobalt acetate solutions. Effects of p H value were studied deeply on Fischer–Tropsch synthesis(FTS) through a semi-batch reactor. Among all impregnation solutions(...The Co-based catalysts were prepared with different cobalt acetate solutions. Effects of p H value were studied deeply on Fischer–Tropsch synthesis(FTS) through a semi-batch reactor. Among all impregnation solutions(water, butanol, amyl alcohol, acetic acid, nitric acid and ammonium nitrate), the catalyst prepared by NH_4NO_3 solution showed the highest catalytic activity due to its small particle size and high reduction degree. However, the catalyst with the smallest particle size derived from water as impregnation solution exhibited low activity as well as high methane selectivity since it was difficult to be reduced and inactive in FTS. According to FT-IR spectra results, the low intensity of absorbed CO on the catalyst prepared from water solution resulted in low FTS activity. Whereas, the high activity of catalysts prepared from NH_4NO_3 solution could be explained by the high intensity of absorbed CO on the catalysts.The cobalt species on the catalysts prepared under lower p H conditions exhibited smaller particle size distribution as well as lower CO conversion than those prepared at higher p H value.展开更多
[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
[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
BACKGROUND: 31P magnetic resonance spectroscopy (31P MRS) can be used to non-injuredly and dynamicly detect various metabolites including phosphorus in organis and reflect changes of phospholipid metabolism and energy...BACKGROUND: 31P magnetic resonance spectroscopy (31P MRS) can be used to non-injuredly and dynamicly detect various 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 31P 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 31P 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 experimental 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 various 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. ② Glioma 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
pH value is regarded as one of the most important attributes that affect sensory characteristics and edible quality of apple.The objective of the research was to explore the feasibility of applying shortwave infrared ...pH value is regarded as one of the most important attributes that affect sensory characteristics and edible quality of apple.The objective of the research was to explore the feasibility of applying shortwave infrared hyperspectral imaging system to detect the pH value of apple.A shortwave infrared hyperspectral imaging system was developed over the wavelength region of 1000-2500 nm and used to acquire hyperspectral images of apple samples.After reflectance calibration,mean reflectance spectral was calculated by averaging the intensity of all pixels within the roundness region of interest(ROI).Synergy interval partial least squares(siPLS)algorithms as an effective multivariable method was conducted on the calibration of regression model to estimate the pH value in Fuji apple.The performance of the final model was back-evaluated according to root mean square error of calibration(RMSEC)and correlation coefficient(Rc)in calibration set,and tested in prediction set.The optimal prediction siPLS model was obtained with correlation coefficient(Rp)of 0.8474 and mean square error of prediction(RMSEP)of 0.0398.The results indicated that shortwave infrared hyperspectral imaging combined with siPLS chemometrics could be an accurate and fast method for nondestructive prediction of pH value in Fuji apple.展开更多
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
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
[Objectives] This study was conducted to understand soil p H changes during tobacco planting and its reasons. [Methods]Soil samples were collected from Jingdong,Jinggu and Zhenyuan tobacco-planting areas of Pu'er ...[Objectives] This study was conducted to understand soil p H changes during tobacco planting and its reasons. [Methods]Soil samples were collected from Jingdong,Jinggu and Zhenyuan tobacco-planting areas of Pu'er City before tobacco planting and during different growth stages of tobacco. [Results] Planting flue-cured tobacco changed the soil p H value. First,it was affected by the nicotine produced by the root system of tobacco plants. Second,it was affected by the type of soil. [Conclusions] This study has certain theoretical guiding significance for the cultivation management of flue-cured tobacco and the arrangement of ensuing crops.展开更多
Water has a pH of around (7.0), making it neither alkaline nor acidic. Alkaline is defined as a pH value greater than (7.0). The power of water to neutralize acids is measured by its alkalinity. The pH scale ranges fr...Water has a pH of around (7.0), making it neither alkaline nor acidic. Alkaline is defined as a pH value greater than (7.0). The power of water to neutralize acids is measured by its alkalinity. The pH scale ranges from (pH = 0 to 14), with anything above (pH = 7.0) being alkaline, and anything below (7.0) being acidic. Much of the research up to now has been investigating the effect of adding alkaline substances to the water to increase the pH levels. Recent evidence suggests that using baking soda (sodium bicarbonate), which is an alkaline substance with a pH of about (9). While studies have shown that adding soda to water increases its alkalinity, it has a number of negative health consequences. For instance, Hypokalemia, Hypochloremia, High levels of sodium in the blood, Worsening kidney disease, Worsening heart failure, Muscle weakness and spasm, and Increased stomach acid production. The main aim of this study is to investigate a natural substance consisting of environmental elements i.e., it is derived from silica by the thermal fusion method (prepared by the authors) that raises the pH of water with a physical field of 80 cm without adding any components to the water. The results showed the effectiveness of this natural substance in its solid and liquid forms in raising the pH of water to reach 8.5 from a distance range = 80 cm, without any side effects on human health.展开更多
In this paper,we have interest in the CdSe(cadmium selenide)semiconductor due to their physical and optical properties that depend on their morphology and size,as well as their possible applications in electronic and ...In this paper,we have interest in the CdSe(cadmium selenide)semiconductor due to their physical and optical properties that depend on their morphology and size,as well as their possible applications in electronic and optoelectronic fields,for example,in the fabrication of solar cells or nanotransistors.For this reason,we synthetized nanoparticles of CdSe using the colloidal method,and varied the pH value:8 to 12,to know the effect of pH on the samples.The nanoparticles were characterized using the SEM(scanning electron microscope)and STM(scanning tunneling microscope)to know the morphology and electronic cloud on the surface of the samples.In each case,we found different sizes(from 6 to 11.5 nm)and shapes as filaments(fibbers),bars and spheres of CdSe nanoparticles and the 3D-FFT was obtained too.展开更多
Cuprous oxide (Cu<sub>2</sub>O) in high yield with controlled shape and size was synthesized via a solution-phase route by reducing cupric sulphate with D-glucose. The solution pH shows strong effects on t...Cuprous oxide (Cu<sub>2</sub>O) in high yield with controlled shape and size was synthesized via a solution-phase route by reducing cupric sulphate with D-glucose. The solution pH shows strong effects on the size and morphology of the products. The products were characterized by X-ray power diffraction (XRD) and Scanning electron microscope (SEM). The infrared emissivity of Cu<sub>2</sub>O was tested by Far infrared emissivity measurer S302. The possible crystal growth processes have been proposed.展开更多
Although their cost-effectiveness and intrinsic safety,aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction,Zn corrosion and passivation,and Zn dendrite formation on th...Although their cost-effectiveness and intrinsic safety,aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction,Zn corrosion and passivation,and Zn dendrite formation on the anode.Despite numerous strategies to alleviate these side reactions have been demonstrated,they can only provide limited performance improvement from a single aspect.Herein,a triple-functional additive with trace amounts,ammonium hydroxide,was demonstrated to comprehensively protect zinc anodes.The results show that the shift of electrolyte pH from 4.1 to 5.2 lowers the HER potential and encourages the in situ formation of a uniform ZHS-based solid electrolyte interphase on Zn anodes.Moreover,cationic NH^(4+)can preferentially adsorb on the Zn anode surface to shield the“tip effect”and homogenize the electric field.Benefitting from this comprehensive protection,dendrite-free Zn deposition and highly reversible Zn plating/stripping behaviors were realized.Besides,improved electrochemical performances can also be achieved in Zn//MnO_(2)full cells by taking the advantages of this triple-functional additive.This work provides a new strategy for stabilizing Zn anodes from a comprehensive perspective.展开更多
The effect of triethyl citrate(TEC)on the stability of cream preparations containing urea or hydroxyethyl urea along with their moisturizing effect on skin was investigated.The results showed that creams incorporating...The effect of triethyl citrate(TEC)on the stability of cream preparations containing urea or hydroxyethyl urea along with their moisturizing effect on skin was investigated.The results showed that creams incorporating urea or hydroxyethyl urea led to increase in pH value after a long-term and high-temperature storage.pH change in the latter one was relatively smaller.With the addition of TEC,the elevated pH of the formula system was suppressed.In the situation of stable formula,the higher the TEC added,the more significant inhibition effect on the pH change was observed.In the moisture retention test in vivo,compared to 27.19%moisture rate in negative control,cream preparations containing 5%urea or 5%hydroxyethyl urea had remarkable moisturizing effect,which were all higher than 52%.The latter one was relatively more prominent.There is no significant effect on moisturizing effect for product with TEC additive.展开更多
Rare earth elements are indispensable raw materials for advanced aero-engines, special optical materials, and high-performance electronic products. With the development of the social economy, the global demand for rar...Rare earth elements are indispensable raw materials for advanced aero-engines, special optical materials, and high-performance electronic products. With the development of the social economy, the global demand for rare earth resources is increasing, and rare earths have become a key metal for the development of new industries and frontier technologies that are highly valued both at home and abroad. Ion-adsorbed rare earth ores are an important source of rare earths, so the efficient green leaching of ion-adsorbed rare earths is important. Researchers found that the selection of an efficient green leaching agent for ion-adsorbed rare earths is based on the zeta potential of tailing clay minerals in addition to leaching efficiency, and both zeta potential and leaching ion concentration are related to mineral acidity and alkalinity, and the pH of tailing water suspension is a direct indicator of environmental water quality requirements. Therefore, the efficiency of the leaching process is closely integrated with the environmental evaluation, and the characteristics and correlation of the changes in zeta potential, pH, conductivity and pollutant concentration of the pulp of clay mineral content during the leaching process of ore leaching and tailings aqueous electrolyte solution leaching are studied by evaluating the leaching system, and a set of correlation leaching efficiency and environmental impact evaluation method is established based on the results of the above analysis, which is of scientific development of ion adsorption rare earth resources. It has important theoretical significance and practical application value.展开更多
基金supported by the Open Foundation of Key Laboratory of the Ministry of Educationof Nonferrous Metal Alloys and Processes(No.EKL09002)The Ph.D.Fund Project of Lanzhou University of Science and Technology(No.BS01200904)
文摘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 La2O3 and MgO.The morphology of the particles is almost flake with the size of～30 nm when pH is 8.0.
基金financial support from the National Natural Science Foundation of China (21528302)Zhejiang Province Natural Science Foundation (LQ15B060004)
文摘The Co-based catalysts were prepared with different cobalt acetate solutions. Effects of p H value were studied deeply on Fischer–Tropsch synthesis(FTS) through a semi-batch reactor. Among all impregnation solutions(water, butanol, amyl alcohol, acetic acid, nitric acid and ammonium nitrate), the catalyst prepared by NH_4NO_3 solution showed the highest catalytic activity due to its small particle size and high reduction degree. However, the catalyst with the smallest particle size derived from water as impregnation solution exhibited low activity as well as high methane selectivity since it was difficult to be reduced and inactive in FTS. According to FT-IR spectra results, the low intensity of absorbed CO on the catalyst prepared from water solution resulted in low FTS activity. Whereas, the high activity of catalysts prepared from NH_4NO_3 solution could be explained by the high intensity of absorbed CO on the catalysts.The cobalt species on the catalysts prepared under lower p H conditions exhibited smaller particle size distribution as well as lower CO conversion than those prepared at higher p H value.
基金School-level Project of Pu'er University (K2017019).
文摘[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.
基金Doctoral Research Start-up Fund Project of Liaoning Province(2019-B-237)National Special Project for the Construction of Modern Agricultural Industrial Technology System(CARS-01-51).
文摘[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.
基金the grants fromHealth Department of HubeiProvince, No. 301140319
文摘BACKGROUND: 31P magnetic resonance spectroscopy (31P MRS) can be used to non-injuredly and dynamicly detect various 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 31P 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 31P 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 experimental 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 various 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. ② Glioma 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.
基金the Beijing Natural Science Foundation(Project No.6144024)Science and Technology Innovation Foundation of Beijing Academy of Agriculture and Forestry Sciences(Project No.CXJJ201314).
文摘pH value is regarded as one of the most important attributes that affect sensory characteristics and edible quality of apple.The objective of the research was to explore the feasibility of applying shortwave infrared hyperspectral imaging system to detect the pH value of apple.A shortwave infrared hyperspectral imaging system was developed over the wavelength region of 1000-2500 nm and used to acquire hyperspectral images of apple samples.After reflectance calibration,mean reflectance spectral was calculated by averaging the intensity of all pixels within the roundness region of interest(ROI).Synergy interval partial least squares(siPLS)algorithms as an effective multivariable method was conducted on the calibration of regression model to estimate the pH value in Fuji apple.The performance of the final model was back-evaluated according to root mean square error of calibration(RMSEC)and correlation coefficient(Rc)in calibration set,and tested in prediction set.The optimal prediction siPLS model was obtained with correlation coefficient(Rp)of 0.8474 and mean square error of prediction(RMSEP)of 0.0398.The results indicated that shortwave infrared hyperspectral imaging combined with siPLS chemometrics could be an accurate and fast method for nondestructive prediction of pH value in Fuji apple.
文摘近日，深圳市内衣行业协会携安莉芳、伊维斯、都市丽人、嫒秀等国内知名内衣品牌闪耀亮相2016中国国际针织（春夏）博览会（简称PH Value春夏针织展），SIUF国际内衣超模冠军姜贝贝领衔国内外名模上演性感内衣大秀，莱特妮丝、夏娃的诱惑、布迪设计、淳度、ZIM等品牌也联合展示最新产品。“深圳气质”领潮时尚，吸引观众层层围观，成为2016 PH Value 春夏针织展的目光聚焦中心。
基金financially supported by National Natural Science Foundation of China (22209133, 22272131, 21972111, 22211540712)Natural Science Foundation of Chongqing (CSTB2022NSCQ-MSX1411)+1 种基金Chongqing Engineering Research Center for Micro-Nano Biomedical Materials and DevicesChongqing Key Laboratory for Advanced Materials and Technologies。
文摘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.
文摘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.
基金Supported by University-level Project of Pu'er University (No. k2017019)。
文摘[Objectives] This study was conducted to understand soil p H changes during tobacco planting and its reasons. [Methods]Soil samples were collected from Jingdong,Jinggu and Zhenyuan tobacco-planting areas of Pu'er City before tobacco planting and during different growth stages of tobacco. [Results] Planting flue-cured tobacco changed the soil p H value. First,it was affected by the nicotine produced by the root system of tobacco plants. Second,it was affected by the type of soil. [Conclusions] This study has certain theoretical guiding significance for the cultivation management of flue-cured tobacco and the arrangement of ensuing crops.
文摘Water has a pH of around (7.0), making it neither alkaline nor acidic. Alkaline is defined as a pH value greater than (7.0). The power of water to neutralize acids is measured by its alkalinity. The pH scale ranges from (pH = 0 to 14), with anything above (pH = 7.0) being alkaline, and anything below (7.0) being acidic. Much of the research up to now has been investigating the effect of adding alkaline substances to the water to increase the pH levels. Recent evidence suggests that using baking soda (sodium bicarbonate), which is an alkaline substance with a pH of about (9). While studies have shown that adding soda to water increases its alkalinity, it has a number of negative health consequences. For instance, Hypokalemia, Hypochloremia, High levels of sodium in the blood, Worsening kidney disease, Worsening heart failure, Muscle weakness and spasm, and Increased stomach acid production. The main aim of this study is to investigate a natural substance consisting of environmental elements i.e., it is derived from silica by the thermal fusion method (prepared by the authors) that raises the pH of water with a physical field of 80 cm without adding any components to the water. The results showed the effectiveness of this natural substance in its solid and liquid forms in raising the pH of water to reach 8.5 from a distance range = 80 cm, without any side effects on human health.
文摘In this paper,we have interest in the CdSe(cadmium selenide)semiconductor due to their physical and optical properties that depend on their morphology and size,as well as their possible applications in electronic and optoelectronic fields,for example,in the fabrication of solar cells or nanotransistors.For this reason,we synthetized nanoparticles of CdSe using the colloidal method,and varied the pH value:8 to 12,to know the effect of pH on the samples.The nanoparticles were characterized using the SEM(scanning electron microscope)and STM(scanning tunneling microscope)to know the morphology and electronic cloud on the surface of the samples.In each case,we found different sizes(from 6 to 11.5 nm)and shapes as filaments(fibbers),bars and spheres of CdSe nanoparticles and the 3D-FFT was obtained too.
文摘Cuprous oxide (Cu<sub>2</sub>O) in high yield with controlled shape and size was synthesized via a solution-phase route by reducing cupric sulphate with D-glucose. The solution pH shows strong effects on the size and morphology of the products. The products were characterized by X-ray power diffraction (XRD) and Scanning electron microscope (SEM). The infrared emissivity of Cu<sub>2</sub>O was tested by Far infrared emissivity measurer S302. The possible crystal growth processes have been proposed.
基金supported by the National Key Research and Development Program of China(2019YFE0114400)the Guangdong Basic and Applied Basic Research Foundation(2021B1515120005)+7 种基金the National Natural Science Foundation of China(32171721)the Guangdong Basic and Applied Basic Research Foundation(2021B151512000)the Guangzhou Science and Technology Plan Project(202102020262)the State Key Laboratory of Pulp&Paper Engineering(2022C01),the State Key Laboratory of Pulp&Paper Engineering(202208)the Engineering and Physical Sciences Research Council(EPSRCEP/V027433/1EP/V027433/2EP/Y008707/1)。
文摘Although their cost-effectiveness and intrinsic safety,aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction,Zn corrosion and passivation,and Zn dendrite formation on the anode.Despite numerous strategies to alleviate these side reactions have been demonstrated,they can only provide limited performance improvement from a single aspect.Herein,a triple-functional additive with trace amounts,ammonium hydroxide,was demonstrated to comprehensively protect zinc anodes.The results show that the shift of electrolyte pH from 4.1 to 5.2 lowers the HER potential and encourages the in situ formation of a uniform ZHS-based solid electrolyte interphase on Zn anodes.Moreover,cationic NH^(4+)can preferentially adsorb on the Zn anode surface to shield the“tip effect”and homogenize the electric field.Benefitting from this comprehensive protection,dendrite-free Zn deposition and highly reversible Zn plating/stripping behaviors were realized.Besides,improved electrochemical performances can also be achieved in Zn//MnO_(2)full cells by taking the advantages of this triple-functional additive.This work provides a new strategy for stabilizing Zn anodes from a comprehensive perspective.
文摘The effect of triethyl citrate(TEC)on the stability of cream preparations containing urea or hydroxyethyl urea along with their moisturizing effect on skin was investigated.The results showed that creams incorporating urea or hydroxyethyl urea led to increase in pH value after a long-term and high-temperature storage.pH change in the latter one was relatively smaller.With the addition of TEC,the elevated pH of the formula system was suppressed.In the situation of stable formula,the higher the TEC added,the more significant inhibition effect on the pH change was observed.In the moisture retention test in vivo,compared to 27.19%moisture rate in negative control,cream preparations containing 5%urea or 5%hydroxyethyl urea had remarkable moisturizing effect,which were all higher than 52%.The latter one was relatively more prominent.There is no significant effect on moisturizing effect for product with TEC additive.
文摘Rare earth elements are indispensable raw materials for advanced aero-engines, special optical materials, and high-performance electronic products. With the development of the social economy, the global demand for rare earth resources is increasing, and rare earths have become a key metal for the development of new industries and frontier technologies that are highly valued both at home and abroad. Ion-adsorbed rare earth ores are an important source of rare earths, so the efficient green leaching of ion-adsorbed rare earths is important. Researchers found that the selection of an efficient green leaching agent for ion-adsorbed rare earths is based on the zeta potential of tailing clay minerals in addition to leaching efficiency, and both zeta potential and leaching ion concentration are related to mineral acidity and alkalinity, and the pH of tailing water suspension is a direct indicator of environmental water quality requirements. Therefore, the efficiency of the leaching process is closely integrated with the environmental evaluation, and the characteristics and correlation of the changes in zeta potential, pH, conductivity and pollutant concentration of the pulp of clay mineral content during the leaching process of ore leaching and tailings aqueous electrolyte solution leaching are studied by evaluating the leaching system, and a set of correlation leaching efficiency and environmental impact evaluation method is established based on the results of the above analysis, which is of scientific development of ion adsorption rare earth resources. It has important theoretical significance and practical application value.
