Synthesis of nanometric TiO2 in aqueous solution by soft chemistry: obtaining of anatase, brookite and rutile with controlled shapes

AbstractNanometric particles of titania, exhibiting anatase, brookite or rutile polymorphs, were synthesized by thermohydrolysis of TiCl4 in aqueous medium. The adjustement of physico-chemical parameters (acidity, ionic strength, anions, temperature) allows to tune the crystalline structure, the size and the morphology of the particles. Brookite results from the precipitation of titanium in HCl, HBr or HNO3 whereas anatase is formed in H2SO4 medium. Adding salts in HCl medium leads to ionic strength or complexation effect. Varying the temperature of thermohydrolysis implies modification on yield, size and morphology of the particles.

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EVALUATION OF PHYSICO-CHEMICAL PARAMETERS OF DIFFERENT SHODHIT GUGGUL

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i9.18668 ◽

2017 ◽

Vol 9 (9) ◽

pp. 247

Author(s):

Mayuree A. Patel ◽

Sanjeev R Acharya ◽

Carol P. Macwan ◽

Tejas B. Patel ◽

B. N. Suhagia

Keyword(s):

Aqueous Solution ◽

Physicochemical Parameters ◽

Ph Value ◽

Water Soluble ◽

Chemical Parameters ◽

Analytical Results ◽

Physico Chemical ◽

Standard Value ◽

The Difference ◽

Physicochemical Data

Objective: The present study was aimed to identify the physicochemical data of shodhit guggul. Guggul is a gum-resin exudate from the plant Commiphora weightii (Arn.) Bhandari, belonging to Burseraceae family. In Ayurveda, guggul is always purified. This purification is known as Shodhan. Shodhan is a process by which guggul is made non-toxic, effective, suitable and fit for therapeutic purposes.Methods: The seven different shodhan dravya were used to prepare shodhit guggul. They were evaluated by performing physicochemical parameters including five different extractive value; total ash, acid insoluble, water soluble and sulphated ash value; pH, and loss on drying.Results: Analytical results of raw guggul showed total ash, acid insoluble ash, water soluble ash and sulphated ash value to 5.36±0.04%, 0.96±0.03%, 4.51±0.03 % and 8.40±0.04% respectively. These all values of each shodhit guggul were different. The extractive value of raw guggul was comparable with standard value while the extractive value of each shodhit guggul was totally different. The pH value of 1% w/v and 10% w/v aqueous solution of raw guggul was 6.44±0.18 though pH of each shodhit guggul was changed. The loss on drying of raw guggul was found to be 1.88±0.02%w/v, however, this value was different for each shodhit guggul.Conclusion: The present study revealed that the different shodhan process with specific shodhan dravya affects the physicochemical parameters. The analysis and comparison of the data showed the difference in the properties of seven shodhit guggul with respect to raw Guggul.

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Coordinating Properties of Aromatic and Aliphatic Sulfur with Bivalent Metals in Aqueous Solution. A Calorimetric Study

Australian Journal of Chemistry ◽

10.1071/ch9790709 ◽

1979 ◽

Vol 32 (4) ◽

pp. 709 ◽

Cited By ~ 3

Author(s):

R Aruga

Keyword(s):

Aqueous Solution ◽

Ionic Strength ◽

Complex Formation ◽

Aqueous Medium ◽

Formation Constants ◽

Calorimetric Study ◽

Thermodynamic Quantities ◽

Direct Calorimetry ◽

Bivalent Metals

Heats and entropies of complex formation of the thiophen-2-carboxylate ion with Ni2+, Cu2+, Zn2+ and Cd2+ have been determined by direct calorimetry, the formation constants being known from the literature. The measurements were carried out in aqueous medium at 25�C and an ionic strength of 1. The values of the thermodynamic quantities for thiophen-2-carboxylate, compared with those for (ethylthio)acetate and (phenylthio)acetate obtained previously, indicate a greater tendency for aromatic sulfur to form bonds with the above metals than for aliphatic sulfur. The causes of this behaviour are discussed.

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Viscosimetric studies of chitosan nitrate and chitosan chlorhydrate in acid free NaCl aqueous solution

e-Polymers ◽

10.1515/epoly.2008.8.1.137 ◽

2008 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Cristóbal Lárez Velásquez ◽

Joel Sánchez Albornoz ◽

Enrique Millán Barrios

Keyword(s):

Aqueous Solution ◽

Ionic Strength ◽

Aqueous Solutions ◽

Aqueous Medium ◽

Intrinsic Viscosity ◽

Free Acid ◽

Film Formation ◽

Stiffness Parameter ◽

Low Ionic Strength

AbstractTwo salts of the biopolymer chitosan were prepared in aqueous medium by employing an excess of HCl or HNO3 in order to ensure neutralization of all NH2-chitosan groups. Chitosan salts were extensively dialyzed in dionised water and dried at 40 ºC until film formation. The films were characterized by thermogravimetry, FTIR and conductimetric tritration. QH+Cl− and QH+NO3− salts were viscosimetrically evaluated in free acid aqueous solutions in the presence of NaCl to control ionic strength of the medium. Unexpected high intrinsic viscosity values were obtained at low ionic strength when QH+NO3− salt were evaluated. Smidsrod´s approach was employed to estimate the stiffness parameter of both salts and B = 0.084 and 0.120 for QH+Cl− and QH+NO3−, respectively, were obtained.

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Rational design of one-dimensional vanadium(v) oxide nanocrystals: an insight into the physico-chemical parameters controlling the crystal structure, morphology and size of particles

CrystEngComm ◽

10.1039/c5ce00554j ◽

2015 ◽

Vol 17 (36) ◽

pp. 6780-6795 ◽

Cited By ~ 11

Author(s):

Nathalie Steunou ◽

Jacques Livage

Keyword(s):

Crystal Structure ◽

Aqueous Solution ◽

Rational Design ◽

Chemical Parameters ◽

One Dimensional ◽

Recent Advances ◽

Physico Chemical ◽

Structure Morphology ◽

Size Of Particles ◽

Insight Into

This highlight deals with the recent advances on the synthesis in aqueous solution of one-dimensional vanadium(v) oxide nanocrystals.

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Controlled synthesis of anganese (oxihydr)oxides in queous olution by hermolysis

MRS Proceedings ◽

10.1557/proc-822-s3.8 ◽

2004 ◽

Vol 822 ◽

Cited By ~ 1

Author(s):

S. Cassaignon ◽

M. Koelsch ◽

J-P. Jolivet

Keyword(s):

Aqueous Medium ◽

Controlled Synthesis ◽

Chemical Parameters ◽

Nanometric Particles

AbstractNanometric particles of manganese (oxihydr)oxides (Hausmannite, Manganite, Nsutite, Pyrolusite and Vernadite) have been synthesized by thermohydrolysis of MnCl2 and/or KMnO4in aqueous medium. The modification of various chemical parameters (pH and precursors concentration, nature of the reducer or oxidizer, temperature and duration of the thermolysis) allow the control of the nature, the size and the morphology of the obtained particles.

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ADSORPTIVE REMOVAL OF PHOSPHATE ONTO IRON LOADED LITCHI CHINENSIS SEED WASTE

Journal of Institute of Science and Technology ◽

10.3126/jist.v23i1.22200 ◽

2019 ◽

Vol 23 (1) ◽

pp. 81-87

Author(s):

Asmita Shrestha ◽

Bhoj Raj Poudel ◽

Manoj Silwal ◽

Megh Raj Pokhrel

Keyword(s):

Waste Water ◽

Aqueous Solution ◽

Phosphate Removal ◽

Chemical Parameters ◽

Litchi Chinensis ◽

Equilibrium Time ◽

Adsorptive Removal ◽

Adsorption Capacities ◽

Physico Chemical ◽

Experiment Method

Raw and charred Fe(III)-loaded Litchi chinensis seed waste (FeRLW and FeCLW) as bio-adsorbents was investigated to remove phosphate from aqueous solution. Various physico-chemical parameters such as equilibrium time, pH and adsorbent dosage were studied by batch experiment method. The maximum adsorption capacities for phosphate removal by FeRLW and FeCLW were found to be 96.5 mg/g and 100 mg/g, respectively. The experimental results revealed that biomaterials of FeRLW and FeCLW can be used as effective and economically viable adsorbents for the removal of phosphate from waste water.

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