The pH Influence on the Preparation of Hollow Fe2O3 Spheres by Hydrothermal Method

2013 ◽  
Vol 669 ◽  
pp. 119-123
Author(s):  
Liang Qiao ◽  
Jie Chen ◽  
Li Qiang Jiang ◽  
Jing Wu Zheng

In this paper Fe2O3 precursor coating on the surface of carbon balls was prepared by hydrothermal method using Fe(NO3)3·9H20 and glucose as the raw materials. After calcination Fe2O3 hollow sphere could be achieved. The influence of pH value on the preparation of hollow Fe2O3 spheres was studied using XRD and SEM respectively. The results show that the pH value has no effect on the formation of Fe2O3 phase, but has a giant influence on the morphology of the hollow spheres. The Fe2O3 hollow spheres were achieved when the pH value was between 3 and 7. The particles with sheet and block structure form when pH7. The mechanism was studied, When 3

2013 ◽  
Vol 28 (4) ◽  
pp. 387-392
Author(s):  
Tong SUN ◽  
Lian-Li LIU ◽  
Shu-Ying XU ◽  
Xiao-Lin PENG ◽  
Hai-Long YANG

2007 ◽  
Vol 336-338 ◽  
pp. 2176-2178 ◽  
Author(s):  
Zhang Lian Hong ◽  
Huang Guo ◽  
Li Xia Peng ◽  
Min Quan Wang

Yttrium oxide hydroxide nitrate (Y4O(OH)9NO3), which was prepared by polyvinyl alcoholassisted hydrothermal method from the Y(NO3)3 and KOH starting solution, was characterized by XRD and FE-SEM. The results revealed that pH value of the starting solution is an important factor which determines the morphology and size of the products. The obtained products varied from lamina microprisms to circular nanorods when the pH value increased from 7.0 to 8.0. In the high pH value above 8.0, the size of nanorods decreased with increasing pH value. A primary mechanism was proposed to explain the evolution of morphology and size of Y4O(OH)9NO3 products prepared under various pH values.


2018 ◽  
Vol 47 (7) ◽  
pp. 2368-2375 ◽  
Author(s):  
Qianqian Wang ◽  
Quan Zong ◽  
Chunlei Zhang ◽  
Hui Yang ◽  
Qilong Zhang

Homogeneous SnO2 hollow spheres have been synthesized through a hydrothermal method without a template, followed by in situ polymerization of PANI.


2014 ◽  
Vol 27 (2) ◽  
pp. 209-213 ◽  
Author(s):  
Xue Lin ◽  
Yv-ning Gong ◽  
Yao-dan Zhang ◽  
Yong-sheng Yan ◽  
Qing-feng Guan

2014 ◽  
Vol 599-601 ◽  
pp. 58-62 ◽  
Author(s):  
Hui Wang ◽  
Lian Li Liu ◽  
Bing Hou ◽  
Jun Jiao Kou ◽  
Li Li Wang

As the raw materials of Na2WO4•2H2O and ZnSO4•7H2O, ZnWO4 micron spheres and nanorods were synthesized with CH3COOH as the complexing agent by a hydrothermal method at 180 °C for 24h. We analyzed the effect of different pH values in reaction solutions on phase compositions, morphologies and luminescent properties of the ZnWO4 powders. The as-synthesized products were characterized by XRD and SEM. The down-conversion spectrum was measured with spectrophotometer under the excitation wavelength of 291nm. The results indicated that there was a wide emission peaks at 400~550nm. The luminescent intensities of ZnWO4 nanorods synthesized at pH value of 9, 10 and 11 were much stronger than that of ZnWO4 micron spheres synthesized between the pH values of 4 to 8.


Author(s):  
Siti Chairiyah Batubara ◽  
Nindia Arum Pratiwi

Teh dan rempah memiliki kandungan antioksidan yang berguna untuk kesehatan. Tujuan dari pembelajaran ini adalah untuk mendapatkan formula minuman fungsional teh dan rempah terbaik. Penelitian ini menggunakan mixture design untuk menentukan formula optimum minuman fungsional terbaik yang terdiri dari gula merah, bubuk kayu manis dan bubuk kapulaga. Berdasarkan input batas atas dan batas bawah dari bahan baku sehingga didapatkan 16 formulasi yang akan diteliti. Untuk batas atas gula merah yaitu 40 dan batas bawah gula merah yaitu 35. Untuk batas atas bubuk kayu manis yaitu 15 dan batas bawah kayu manis yaitu 10. Untuk batas atas bubuk kapulaga yaitu 50 dan batas bawah bubuk kapulaga yaitu 45. Untuk menentukan kualitas minuman fungsional dilakukan uji kimia (uji karbohidrat, gula total dan nilai pH, uji fisik (Uji viskositas), uji organoleptik (uji hedonik untuk warna, aroma, rasa dan kekentalan) dan mutu hedonik yang ditentukan dari kesukaan panelis terhadap warna, aroma, rasa dan kekentalan) dan uji antioksidan. Penelitian ini untuk mendapatkan formula optimum yang terbaik dari hasil pengacakan oleh mixture design. Hasil dari pengolahan mixture design adalah anova, grafik dan duncan. Berdasarkan hasil penelitian formula minuman fungsional yang masih dapat diterima adalah formulasi 11 yang terdiri dari 40% gula merah, 12.67% bubuk kayu manis dan 47.32% bubuk kapulaga. Formula 11 mengandung 0.39% karbohidrat, 15.46% gula total, 5.38% pH 4.98%  viskositas dan 255.41 mg antoksidanSpice tea have antioxidants compounds that are beneficial for health. The purpose of this study was to get the best spice tea formulation as a functional drink. This research used a mixture design to obtain the best optimum formula functional drink that composed by brown sugar, cinnamon powder and cardamom powder. Based on input the upper and lower limits of raw materials then get 16 formulations will be researched. The upper limit of brown sugar, cinnamon powder and cardamom powder is 40, 15 and 50. The lower limit of brown sugar, cinnamon powder and cardamom powder is 35, 10 and 45. The functional drink quality determined by chemical test (carbohydrate level, total sugar and pH value), physical test (viscosity level), organoleptic test and antioxidan level. Data was processed statistically using Design Expert application with one-way analysis (one way ANOVA) at 95% confidence level. Duncan`s follow-up was carried out to find out the differences between treatments if ANOVA had a significant effect. Based on the results of the research, formulation functional drink are still aceptable is formulation 11 of 40% brown sugar, 12.67% cinnamon powder and 47.32% cardamom powder. Formulation 11 contained carbohydrate level 0.39%, total sugar 15.46% and pH value 5.38%, viscosity level 4.98%, and antioxidan level 255.41 mg


2017 ◽  
Vol 896 ◽  
pp. 167-174 ◽  
Author(s):  
Zhi Yuan Yang ◽  
Zhuo Yue Meng ◽  
Zhi Hua Li ◽  
Si Tong Wang

Polyethylene glycol (PEG-200) and itaconic acid (IA) were used as raw materials to compound macromer through esterification reaction. A new type of specialized water-coke slurry dispersant was synthesized by copolymerization of microware, sodium methallyl sulfonate (SMAS) and maleic anhydride (MA). The experiment showed that the concentration of slurry could be reached to 63% with the dosage of 0.2%, and the apparent viscosity was 1140.3 mPa∙s. Through the analysis of the infrared, the dispersant was confirmed to have polyethylene glycol branched chain and hydrophilic functional groups such as carboxyl or sulfonic group. When the concentration of dispersant was 30 g/L, the surface tension of water could be decreased from 72.70 mN/m to 45.50 mN/m. Furthermore, when the solution pH value was 9, the Zeta potential of semi-coke powder surface could also be decreased from-13.38 mV to-25 mV with the addition of dispersant. Thus, this dispersant could increase electronegativity of semi-coke powder surface, enhance steric-hindrance effect and prevent the phenomenon of powder flocculation and gather. Meantime, it also could reinforce the semi-coke hydrophilic by reducing the surface tension of water effectively. And then, the high performance water-coke slurry could be obtained.


2013 ◽  
Vol 787 ◽  
pp. 58-64 ◽  
Author(s):  
Xiang Feng Li ◽  
Zhao Zhang ◽  
Fang Liu ◽  
Shu Ping Zheng

The LiFePO4/C composites with different morphology are synthesized by a novel glucose assisted hydrothermal method at various glucose concentrations (from 0 to 0.25mol/L) and the insoluble lithium source Li2CO3, (NH4)2Fe (SO4)2·6H2O and (NH4)2HPO4(n (Li):n (Fe):n (P)=1:1:1) are used as raw materials. The structure, morphology, thermal performance and electrochemical properties of the synthesized composites are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), thermogravimetry/differential scanning calorimetry (TG-DSC), galvanostatic charge/discharge tests and cyclic voltammetry (CV). The results show that the LiFePO4/C synthesized with 0.125mol/L glucose has the relatively small particles size (0.1~0.5μm) and the well spherical morphology. The optimal sample exhibits a high discharge capacity of 160.0mAh/g at the first cycle and exhibits a good reversibility and stability in CV tests.


Author(s):  
О.В. ПРИСТУПКО ◽  
Л.Я. РОДИОНОВА

Разработаны рецептуры напитков функционального назначения из овощных соков с добавлением концентрата из пророщенного зерна полбы Руно . Исследована комплексообразующая способность (КС) напитка при оптимальном соотношении белка и пектина. Определен химический состав используемого сырья и энергетическая ценность готовых напитков. Установлено содержание в 100 г разработанного напитка, образец 1 и 2 соответственно: сухих веществ 8,6 и 7,2 пектиновых веществ 1,80 и 1,79 белков 3,46 и 3,40 г углеводов 10,46 и 7,87 г жиров по 0,14 г. КС образцов 1 и 2 соответственно (58 0,1) и (56 0,2) мг Pb2/мл значение pH 5,1 0,3 и 5,3 0,4. Разработанные овощные соки с мякотью, обогащенные пророщенным зерном полбы Руно , могут быть рекомендованы в качестве овощных напитков функциональной направленности. Recipes of functional drinks from vegetable juices with the addition of concentrate from sprouted grain of spelt Runo have been developed. The complexing ability of the drink with the optimal ratio of protein and pectin was studied. Was determined the chemical composition of the raw materials used and the energy value of the finished beverages. The content of 100 g of developed drinks, the samples 1 and 2, respectively: dry solids 8,6 and 7,2 pectin substances 1,80 and 1,79 proteins 3,46 and 3,40 g carbohydrates 10,46 and 7,87 g of fats in each sample of 0,14 g. The complexing ability of samples 1 and 2, respectively (58 0,1) and (56 0,2) mg Pb2/ml the pH value, respectively 5,1 0,3 and 5,3 0,4. Developed vegetable juices with pulp, enriched with sprouted grain of spelt Runo , can be recommended as vegetable drinks of a functional orientation.


Holzforschung ◽  
2004 ◽  
Vol 58 (4) ◽  
pp. 408-412 ◽  
Author(s):  
C. Xing ◽  
S.Y. Zhang ◽  
J. Deng

Abstract Knowledge of pH and buffering capacity of raw fiber materials is important for understanding the effects of raw material on the curing rate of urea formaldehyde (UF) resin, used for panel manufacturing, especially with some less-desirable wood materials such as bark, top, and commercial thinnings. The effects of pH and buffering capacity as well as catalyst content on the gel time of UF resin were investigated. The results obtained from this study indicate that bark has a lower pH value as well as higher acid and alkaline buffering capacities than wood of the same species due to their extractives. The pH values of the raw fiber materials studied decrease with increased absolute and relative acid buffering capacity due to the increased absolute acidity mass in the solution. At lower levels of added catalyst, the effect of raw material pH on UF resin gel time is significant, while it is insignificant at higher catalyst contents. This may be due to the acidity of wood, which is the main acid catalyst source of the mixture at lower levels of added catalyst, while at higher levels, catalyst is the main source. With higher catalyst contents, all studied raw materials mixed with UF resin result in a longer gel time than does UF resin alone.


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