Method and system for producing hydrogen using sodium ion separation membranes

DOEpatents

Bingham, Dennis N; Klingler, Kerry M; Turner, Terry D; Wilding, Bruce M; Frost, Lyman

2013-05-21

A method of producing hydrogen from sodium hydroxide and water is disclosed. The method comprises separating sodium from a first aqueous sodium hydroxide stream in a sodium ion separator, feeding the sodium produced in the sodium ion separator to a sodium reactor, reacting the sodium in the sodium reactor with water, and producing a second aqueous sodium hydroxide stream and hydrogen. The method may also comprise reusing the second aqueous sodium hydroxide stream by combining the second aqueous sodium hydroxide stream with the first aqueous sodium hydroxide stream. A system of producing hydrogen is also disclosed.

The effect of polymers onto the size of zinc layered hydroxide salt and its calcined product

NASA Astrophysics Data System (ADS)

Hussein, Mohd Zobir bin; Ghotbi, Mohammad Yeganeh; Yahaya, Asmah Hj; Abd Rahman, Mohd Zaki

2009-02-01

Zinc hydroxide nitrate, a brucite-like layered material was synthesized using pH control method. Poly(vinyl alcohol) and poly(ethylene glycol) were used at various percentages as size decreasing agents during the synthesis of zinc hydroxide nitrate. SEM and PXRD showed the decrease of size and thickness of the resultant zinc hydroxide nitrates. TG and surface area data confirmed the decrease of the particle sizes, too. When zinc hydroxide nitrates were heat treated at 500 °C, the physical properties of nano zinc oxides obtained depended on the parent material, zinc hydroxide nitrate.

40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to discharges...

21 CFR 582.1428 - Magnesium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium hydroxide. 582.1428 Section 582.1428 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1428 Magnesium hydroxide. (a) Product. Magnesium hydroxide. (b) Conditions of use. This...

40 CFR 721.10504 - Surface modified magnesium hydroxide (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Surface modified magnesium hydroxide... Specific Chemical Substances § 721.10504 Surface modified magnesium hydroxide (generic). (a) Chemical... as surface modified magnesium hydroxide (PMN P-06-682) is subject to reporting under this section for...

21 CFR 582.1428 - Magnesium hydroxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Magnesium hydroxide. 582.1428 Section 582.1428 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1428 Magnesium hydroxide. (a) Product. Magnesium hydroxide. (b) Conditions of use. This...

21 CFR 582.1428 - Magnesium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Magnesium hydroxide. 582.1428 Section 582.1428 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1428 Magnesium hydroxide. (a) Product. Magnesium hydroxide. (b) Conditions of use. This...

40 CFR 721.10573 - Magnesium hydroxide surface treated with substituted alkoxysilanes (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Magnesium hydroxide surface treated... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10573 Magnesium hydroxide surface... to reporting. (1) The chemical substance identified generically as magnesium hydroxide surface...

21 CFR 582.1428 - Magnesium hydroxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Magnesium hydroxide. 582.1428 Section 582.1428 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1428 Magnesium hydroxide. (a) Product. Magnesium hydroxide. (b) Conditions of use. This...

40 CFR 721.10504 - Surface modified magnesium hydroxide (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Surface modified magnesium hydroxide... Specific Chemical Substances § 721.10504 Surface modified magnesium hydroxide (generic). (a) Chemical... as surface modified magnesium hydroxide (PMN P-06-682) is subject to reporting under this section for...

40 CFR 721.10573 - Magnesium hydroxide surface treated with substituted alkoxysilanes (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Magnesium hydroxide surface treated... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10573 Magnesium hydroxide surface... to reporting. (1) The chemical substance identified generically as magnesium hydroxide surface...

21 CFR 582.1428 - Magnesium hydroxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Magnesium hydroxide. 582.1428 Section 582.1428 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1428 Magnesium hydroxide. (a) Product. Magnesium hydroxide. (b) Conditions of use. This...

21 CFR 582.1205 - Calcium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Calcium hydroxide. 582.1205 Section 582.1205 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1205 Calcium hydroxide. (a) Product. Calcium hydroxide. (b) Conditions of use. This...

21 CFR 582.1631 - Potassium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium hydroxide. 582.1631 Section 582.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1631 Potassium hydroxide. (a) Product. Potassium hydroxide. (b) Conditions of use. This...

21 CFR 582.1631 - Potassium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Potassium hydroxide. 582.1631 Section 582.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1631 Potassium hydroxide. (a) Product. Potassium hydroxide. (b) Conditions of use. This...

21 CFR 582.1631 - Potassium hydroxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Potassium hydroxide. 582.1631 Section 582.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1631 Potassium hydroxide. (a) Product. Potassium hydroxide. (b) Conditions of use. This...

21 CFR 582.1631 - Potassium hydroxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Potassium hydroxide. 582.1631 Section 582.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1631 Potassium hydroxide. (a) Product. Potassium hydroxide. (b) Conditions of use. This...

21 CFR 582.1631 - Potassium hydroxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Potassium hydroxide. 582.1631 Section 582.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1631 Potassium hydroxide. (a) Product. Potassium hydroxide. (b) Conditions of use. This...

Process for changing caking coals to noncaking coals

DOEpatents

Beeson, Justin L.

1980-01-01

Caking coals are treated in a slurry including alkaline earth metal hydroxides at moderate pressures and temperatures in air to form noncaking carbonaceous material. Hydroxides such as calcium hydroxide, magnesium hydroxide or barium hydroxide are contemplated for slurrying with the coal to interact with the agglomerating constituents. The slurry is subsequently dewatered and dried in air at atmospheric pressure to produce a nonagglomerating carbonaceous material that can be conveniently handled in various coal conversion and combustion processes.

Controllable synthesis of layered Co-Ni hydroxide hierarchical structures for high-performance hybrid supercapacitors

NASA Astrophysics Data System (ADS)

Yuan, Peng; Zhang, Ning; Zhang, Dan; Liu, Tao; Chen, Limiao; Ma, Renzhi; Qiu, Guanzhou; Liu, Xiaohe

2016-01-01

A facile solvothermal method is developed for synthesizing layered Co-Ni hydroxide hierarchical structures by using hexamethylenetetramine (HMT) as alkaline reagent. The electrochemical measurements reveal that the specific capacitances of layered bimetallic (Co-Ni) hydroxides are generally superior to those of layered monometallic (Co, Ni) hydroxides. The as-prepared Co0.5Ni0.5 hydroxide hierarchical structures possesses the highest specific capacitance of 1767 F g-1 at a galvanic current density of 1 A g-1 and an outstanding specific capacitance retention of 87% after 1000 cycles. In comparison with the dispersed nanosheets of Co-Ni hydroxide, layered hydroxide hierarchical structures show much superior electrochemical performance. This study provides a promising method to construct hierarchical structures with controllable transition-metal compositions for enhancing the electrochemical performance in hybrid supercapacitors.

40 CFR 721.4600 - Recovered metal hydroxide.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Recovered metal hydroxide. 721.4600... Substances § 721.4600 Recovered metal hydroxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a recovered metal hydroxide (PMN P-91-809...

Polysulfide intercalated layered double hydroxides for metal capture applications

DOEpatents

Kanatzidis, Mercouri G.; Ma, Shulan

2017-04-04

Polysulfide intercalated layered double hydroxides and methods for their use in vapor and liquid-phase metal capture applications are provided. The layered double hydroxides comprise a plurality of positively charged host layers of mixed metal hydroxides separated by interlayer spaces. Polysulfide anions are intercalated in the interlayer spaces.

21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

Code of Federal Regulations, 2010 CFR

2010-04-01

... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white, odorless, tasteless, amorphous powder consisting essentially of aluminum hydroxide (Al2 O3· XH2 O). (2) Color additive...

21 CFR 73.1326 - Chromium hydroxide green.

Code of Federal Regulations, 2010 CFR

2010-04-01

... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1326 Chromium hydroxide green. (a) Identity. (1) The color additive chromium hydroxide green is principally hydrated chromic sesquioxide (Cr2O3·XH2O). (2) Color additive mixtures for drug use made with chromium hydroxide green may contain only those...

40 CFR 415.60 - Applicability; description of the chlorine and sodium or potassium hydroxide production subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... chlorine and sodium or potassium hydroxide production subcategory. 415.60 Section 415.60 Protection of... MANUFACTURING POINT SOURCE CATEGORY Chlor-alkali Subcategory (Chlorine and Sodium or Potassium Hydroxide Production) § 415.60 Applicability; description of the chlorine and sodium or potassium hydroxide production...

40 CFR 415.60 - Applicability; description of the chlorine and sodium or potassium hydroxide production subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... chlorine and sodium or potassium hydroxide production subcategory. 415.60 Section 415.60 Protection of... MANUFACTURING POINT SOURCE CATEGORY Chlor-alkali Subcategory (Chlorine and Sodium or Potassium Hydroxide Production) § 415.60 Applicability; description of the chlorine and sodium or potassium hydroxide production...

21 CFR 184.1428 - Magnesium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... salt or by hydration of reactive grades of magnesium oxide. (b) The ingredient meets the specifications... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Magnesium hydroxide. 184.1428 Section 184.1428... Listing of Specific Substances Affirmed as GRAS § 184.1428 Magnesium hydroxide. (a) Magnesium hydroxide...

21 CFR 184.1428 - Magnesium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... hydration of reactive grades of magnesium oxide. (b) The ingredient meets the specifications of the Food... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium hydroxide. 184.1428 Section 184.1428 Food... Specific Substances Affirmed as GRAS § 184.1428 Magnesium hydroxide. (a) Magnesium hydroxide (Mg(OH)2, CAS...

21 CFR 582.1763 - Sodium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium hydroxide. 582.1763 Section 582.1763 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1763 Sodium hydroxide. (a) Product. Sodium hydroxide. (b) Conditions of use. This substance...

21 CFR 582.1763 - Sodium hydroxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium hydroxide. 582.1763 Section 582.1763 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1763 Sodium hydroxide. (a) Product. Sodium hydroxide. (b) Conditions of use. This substance...

21 CFR 582.1763 - Sodium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium hydroxide. 582.1763 Section 582.1763 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1763 Sodium hydroxide. (a) Product. Sodium hydroxide. (b) Conditions of use. This substance...

21 CFR 582.1763 - Sodium hydroxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium hydroxide. 582.1763 Section 582.1763 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1763 Sodium hydroxide. (a) Product. Sodium hydroxide. (b) Conditions of use. This substance...

21 CFR 582.1763 - Sodium hydroxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium hydroxide. 582.1763 Section 582.1763 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1763 Sodium hydroxide. (a) Product. Sodium hydroxide. (b) Conditions of use. This substance...

40 CFR 415.60 - Applicability; description of the chlorine and sodium or potassium hydroxide production subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... chlorine and sodium or potassium hydroxide production subcategory. 415.60 Section 415.60 Protection of... MANUFACTURING POINT SOURCE CATEGORY Chlor-alkali Subcategory (Chlorine and Sodium or Potassium Hydroxide Production) § 415.60 Applicability; description of the chlorine and sodium or potassium hydroxide production...

40 CFR 415.60 - Applicability; description of the chlorine and sodium or potassium hydroxide production subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... chlorine and sodium or potassium hydroxide production subcategory. 415.60 Section 415.60 Protection of... MANUFACTURING POINT SOURCE CATEGORY Chlor-alkali Subcategory (Chlorine and Sodium or Potassium Hydroxide Production) § 415.60 Applicability; description of the chlorine and sodium or potassium hydroxide production...

40 CFR 415.60 - Applicability; description of the chlorine and sodium or potassium hydroxide production subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... chlorine and sodium or potassium hydroxide production subcategory. 415.60 Section 415.60 Protection of... MANUFACTURING POINT SOURCE CATEGORY Chlor-alkali Subcategory (Chlorine and Sodium or Potassium Hydroxide Production) § 415.60 Applicability; description of the chlorine and sodium or potassium hydroxide production...

Antimicrobial Activity of Calcium Hydroxide in Endodontics: A Review

PubMed Central

Shalavi, S; Yazdizadeh, M

2012-01-01

The purpose of endodontic therapy is to preserve the patient's natural teeth without compromising the patient's local or systemic health. Calcium hydroxide has been included in several materials and antimicrobial formulations that are used in several treatment modalities in endodontics, such as inter-appointment intracanal medicaments. The purpose of this article was to review the antimicrobial properties of calcium hydroxide in endodontics. Calcium hydroxide has a high pH (approximately 12.5-12.8) and is classified chemically as a strong base. The lethal effects of calcium hydroxide on bacterial cells are probably due to protein denaturation and damage to DNA and cytoplasmic membranes. Calcium hydroxide has a wide range of antimicrobial activity against common endodontic pathogens but is less effective against Enterococcus faecalis and Candida albicans. Calcium hydroxide is also a valuable anti-endotoxin agent. However, its effect on microbial biofilms is controversial. PMID:23323217

21 CFR 872.3250 - Calcium hydroxide cavity liner.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

21 CFR 872.3250 - Calcium hydroxide cavity liner.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

21 CFR 184.1763 - Sodium hydroxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg. No. 1310-73-2) is also known as sodium hydrate, soda lye, caustic soda, white caustic, and lye. The...

21 CFR 184.1763 - Sodium hydroxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg. No. 1310-73-2) is also known as sodium hydrate, soda lye, caustic soda, white caustic, and lye. The...

21 CFR 184.1763 - Sodium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg. No. 1310-73-2) is also known as sodium hydrate, soda lye, caustic soda, white caustic, and lye. The...

21 CFR 184.1763 - Sodium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg. No. 1310-73-2) is also known as sodium hydrate, soda lye, caustic soda, white caustic, and lye. The...

21 CFR 872.3250 - Calcium hydroxide cavity liner.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

21 CFR 872.3250 - Calcium hydroxide cavity liner.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

21 CFR 872.3250 - Calcium hydroxide cavity liner.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

21 CFR 73.1326 - Chromium hydroxide green.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Chromium hydroxide green. 73.1326 Section 73.1326... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1326 Chromium hydroxide green. (a) Identity. (1) The color additive chromium hydroxide green is principally hydrated chromic sesquioxide (Cr2O3·XH2O...

Ytterbium coating of spherical Ni(OH) 2 cathode materials for Ni-MH batteries at elevated temperature

NASA Astrophysics Data System (ADS)

He, Xiangming; Wang, Li; Li, Wen; Jiang, Changyin; Wan, Chunrong

The Yb/Co coated nickel hydroxides were prepared by precipitation of Yb(OH) 3 on the surface of spherical nickel hydroxide, followed by precipitation of Co(OH) 2 on its surface. The optimum coating content of ytterbium was around 2% (atomic concentration) to obtain high discharge capacity at 60 °C. It was shown that the discharge capacity of nickel hydroxide at high temperatures was improved by coating of ytterbium and cobalt hydroxide. The high temperature performances of the sealed AAA-sized Ni-MH batteries using Yb/Co coated nickel hydroxide as positive electrodes were carried out, showing much better than those using the un-coated and only Co(OH) 2 coated nickel hydroxide electrodes. The charge acceptance of the battery using 2% Yb and 2% Co coated nickel hydroxide reached 92% at 60 °C, where the charge acceptances for the un-coated and only cobalt coated ones were only 42 and 46%, respectively. It has shown that the Yb/Co coating is an effective way to improve the high temperature performance of nickel hydroxide for nickel-metal hydride batteries.

Comparison of phenol and sodium hydroxide chemical matricectomies for the treatment of ingrowing toenails.

PubMed

Bostanci, Seher; Kocyigit, Pelin; Gürgey, Erbak

2007-06-01

Chemical matricectomy is performed mainly by two agents: phenol and sodium hydroxide. Both agents have excellent cure rates, but there are no data about the comparison of postoperative healing periods. This study was designed to compare the postoperative morbidity rates of sodium hydroxide and phenol matricectomies. Forty-six patients with 154 ingrowing nail sides were treated with either sodium hydroxide or phenol matricectomy. In the postoperative period, the patients were evaluated for the duration and severity of pain, drainage, and peripheral tissue destruction; complete healing periods; and overall success rates. The incidence of pain was higher in the sodium hydroxide group on the first visit, on the second day, but all patients became pain-free after that. The incidence and duration of drainage and peripheral tissue destruction was significantly higher in the phenol group. The mean period for complete recovery was 10.8 days in the sodium hydroxide group, whereas it was 18.02 days in the phenol group. The overall success rates in the sodium hydroxide and phenol groups were found to be 95.1 and 95.8%, respectively. Both sodium hydroxide and phenol are effective agents giving high success rates, but sodium hydroxide causes less postoperative morbidity and provides faster recovery.

Antimicrobial activity of calcium hydroxide and chlorhexidine on intratubular Candida albicans

PubMed Central

Jacques Rezende Delgado, Ronan; Helena Gasparoto, Thaís; Renata Sipert, Carla; Ramos Pinheiro, Claudia; Gomes de Moraes, Ivaldo; Brandão Garcia, Roberto; Antônio Hungaro Duarte, Marco; Monteiro Bramante, Clóvis; Aparecido Torres, Sérgio; Pompermaier Garlet, Gustavo; Paula Campanelli, Ana; Bernardineli, Norberti

2013-01-01

This study investigated the efficacy of calcium hydroxide and chlorhexidine gel for the elimination of intratubular Candida albicans (C. albicans). Human single-rooted teeth contaminated with C. albicans were treated with calcium hydroxide, 2% chlorhexidine gel, calcium hydroxide plus 2% chlorhexidine gel, or saline (0.9% sodium chloride) as a positive control. The samples obtained at depths of 0–100 and 100–200 µm from the root canal system were analyzed for C. albicans load by counting the number of colony forming units and for the percentage of viable C. albicans using fluorescence microscopy. First, the antimicrobial activity of calcium hydroxide and the 2% chlorhexidine gel was evaluated by counting the number of colony forming units. After 14 days of intracanal medication, there was a significant decrease in the number of C. albicans colony forming units at a depth of 0–100 µm with chlorhexidine treatment either with or without calcium hydroxide compared with the calcium hydroxide only treatment. However, there were no differences in the number of colony forming units at the 100–200 µm depth for any of the medications investigated. C. albicans viability was also evaluated by vital staining techniques and fluorescence microscopy analysis. Antifungal activity against C. albicans significantly increased at both depths in the chlorhexidine groups with and without calcium hydroxide compared with the groups treated with calcium hydroxide only. Treatments with only chlorhexidine or chlorhexidine in combination with calcium hydroxide were effective for elimination of C. albicans. PMID:23538639

Evaluation of calcium ion, hydroxyl ion release and pH levels in various calcium hydroxide based intracanal medicaments: An in vitro study

PubMed Central

Fulzele, Punit; Baliga, Sudhindra; Thosar, Nilima; Pradhan, Debaprya

2011-01-01

Aims: Evaluation of calcium ion and hydroxyl ion release and pH levels in various calcium hydroxide based intracanal medicaments. Objective: The purpose of this study was to evaluate calcium and hydroxyl ion release and pH levels of calcium hydroxide based products, namely, RC Cal, Metapex, calcium hydroxide with distilled water, along with the new gutta-percha points with calcium hydroxide. Materials and Methods: The materials were inserted in polyethylene tubes and immersed in deionized water. The pH variation, Ca++ and OH- release were monitored periodically for 1 week. Statistical Analysis Used: Statistical analysis was carried out using one-way analysis of variance and Tukey's post hoc tests with PASW Statistics version 18 software to compare the statistical difference. Results: After 1 week, calcium hydroxide with distilled water and RC Cal raised the pH to 12.7 and 11.8, respectively, while a small change was observed for Metapex, calcium hydroxide gutta-percha points. The calcium released after 1 week was 15.36 mg/dL from RC Cal, followed by 13.04, 1.296, 3.064 mg/dL from calcium hydroxide with sterile water, Metapex and calcium hydroxide gutta-percha points, respectively. Conclusions: Calcium hydroxide with sterile water and RC Cal pastes liberate significantly more calcium and hydroxyl ions and raise the pH higher than Metapex and calcium hydroxidegutta-percha points. PMID:22346155

21 CFR 184.1205 - Calcium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Calcium hydroxide. 184.1205 Section 184.1205 Food... Specific Substances Affirmed as GRAS § 184.1205 Calcium hydroxide. (a) Calcium hydroxide (Ca(OH)2, CAS Reg. No. 1305-62-0) is also known as slaked lime or calcium hydrate. It is produced by the hydration of...

21 CFR 184.1763 - Sodium hydroxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg. No. 1310-73-2) is also known as sodium hydrate, soda lye, caustic soda, white caustic, and lye. The empirical formula is NaOH. Sodium...

21 CFR 184.1205 - Calcium hydroxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Calcium hydroxide. 184.1205 Section 184.1205 Food... GRAS § 184.1205 Calcium hydroxide. (a) Calcium hydroxide (Ca(OH)2, CAS Reg. No. 1305-62-0) is also known as slaked lime or calcium hydrate. It is produced by the hydration of lime. (b) The ingredient...

The alpha-form of the hydroxides of bivalent metals

NASA Technical Reports Server (NTRS)

Feitknecht, W.

1984-01-01

X-ray analyses were made of the hydroxides of the bivalent metals. The freshly pptd. hydroxide is usually in the alpha-form, which on standing is converted to another form or other forms. The alpha and c grating dimensions of the alpha-form and the C6-type of Co, Zn, C, Co-Zn and Ni-Zn hydroxides are tabulated. Ni hydroxide does not exhibit an alpha-form. The alpha-Co(OH)2, the blue form, is stabilized by sugar or by the higher alcohols: these compounds do not stabilize alpha-Zn(OH)2.

Ammonium hydroxide poisoning

MedlinePlus

Ammonium hydroxide is a colorless liquid chemical solution. It is in a class of substances called caustics. Ammonium hydroxide forms when ammonia dissolves in water. This article discusses poisoning from ...

DOUBLE SHELL TANK (DST) HYDROXIDE DEPLETION MODEL FOR CARBON DIOXIDE ABSORPTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

OGDEN DM; KIRCH NW

2007-10-31

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbon dioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbon dioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed.

21 CFR 582.1139 - Ammonium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Additives § 582.1139 Ammonium hydroxide. (a) Product. Ammonium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

21 CFR 582.1205 - Calcium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Additives § 582.1205 Calcium hydroxide. (a) Product. Calcium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

Magnesium Hydroxide

MedlinePlus

Magnesium hydroxide is used on a short-term basis to treat constipation.This medication is sometimes prescribed ... Magnesium hydroxide come as a tablet and liquid to take by mouth. It usually is taken as ...

Aluminum Hydroxide

MedlinePlus

Aluminum hydroxide is used for the relief of heartburn, sour stomach, and peptic ulcer pain and to ... Aluminum hydroxide comes as a capsule, a tablet, and an oral liquid and suspension. The dose and ...

21 CFR 582.1205 - Calcium hydroxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Additives § 582.1205 Calcium hydroxide. (a) Product. Calcium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

21 CFR 582.1139 - Ammonium hydroxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Additives § 582.1139 Ammonium hydroxide. (a) Product. Ammonium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

21 CFR 582.1205 - Calcium hydroxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Additives § 582.1205 Calcium hydroxide. (a) Product. Calcium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

21 CFR 582.1139 - Ammonium hydroxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Additives § 582.1139 Ammonium hydroxide. (a) Product. Ammonium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

21 CFR 582.1139 - Ammonium hydroxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Additives § 582.1139 Ammonium hydroxide. (a) Product. Ammonium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

21 CFR 582.1139 - Ammonium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Additives § 582.1139 Ammonium hydroxide. (a) Product. Ammonium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

21 CFR 582.1205 - Calcium hydroxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Additives § 582.1205 Calcium hydroxide. (a) Product. Calcium hydroxide. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding...

Pretreatment of rapeseed straw by sodium hydroxide.

PubMed

Kang, Kyeong Eop; Jeong, Gwi-Taek; Park, Don-Hee

2012-06-01

Pretreatment method for rapeseed straw by sodium hydroxide was investigated for production of bioethanol and biobutanol. Various pretreatment parameters, including temperature, time, and sodium hydroxide concentration were optimized using a statistical method which is a central composite design of response surface methodology. In the case of sodium hydroxide pretreatment, optimal pretreatment conditions were found to be 7.9% sodium hydroxide concentration, 5.5 h of reaction time, and 68.4 °C of reaction temperature. The maximum glucose yield which can be recovered by enzymatic hydrolysis at the optimum conditions was 95.7% and the experimental result was 94.0 ± 4.8%. This experimental result was in agreement with the model prediction. An increase of surface area and pore size in pretreated rapeseed straw by sodium hydroxide pretreatment was observed by scanning electron microscope.

Sodium hydroxide poisoning

MedlinePlus

Sodium hydroxide is a very strong chemical. It is also known as lye and caustic soda. This ... poisoning from touching, breathing in (inhaling), or swallowing sodium hydroxide. This article is for information only. Do ...

Lifetime of Sodium Beta-Alumina Membranes in Molten Sodium Hydroxide

DTIC Science & Technology

2008-07-01

ABSTRACT Summary: Sodium metal can be made by electrolysis of molten sodium hydroxide in sodium beta-alumina membrane electrolysis cells... electrolysis of molten sodium hydroxide in sodium ”-alumina membrane electrolysis cells. However, there are some uncertainties about the lifetime of the...the properties of the membrane degrade upon long term contact with molten sodium hydroxide. Electrolysis cells were designed, but it proved

Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bortolaz de Oliveira, Henrique; Wypych, Fernando, E-mail: wypych@ufpr.br

Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO{sub 4}{sup 2−}/g of material, respectively. Although the removal values obtained for Zn/NiHN andmore » Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO{sub 4}{sup 2−}/g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated. - Highlights: • Zinc hydroxide nitrate and Zn/Ni hydroxide nitrate or acetate were synthesized. • The interlayer anions were replaced by chromate anions at pH=8.0. • Only Zn/Ni hydroxide nitrate or acetate have the structure preserved after exchange. • Fast exchange reaction and high capacity of chromate removal were observed. • Magnetic materials were obtained to facilitate the solids removal the from solutions.« less

Effect of the Association of Nonsteroidal Anti-inflammatory and Antibiotic Drugs on Antibiofilm Activity and pH of Calcium Hydroxide Pastes.

PubMed

de Freitas, Rafaela Pignatti; Greatti, Vanessa Raquel; Alcalde, Murilo Priori; Cavenago, Bruno Cavalini; Vivan, Rodrigo Ricci; Duarte, Marco Antonio Hungaro; Weckwerth, Ana Carolina Villas Bôas; Weckwerth, Paulo Henrique

2017-01-01

The objective of the present study was to evaluate the in vitro antibiofilm activity and pH of calcium hydroxide associated with different nonsteroidal anti-inflammatory drugs (NSAIDs). The groups analyzed were as follows: group 1, calcium hydroxide paste with propylene glycol; group 2, calcium hydroxide paste with propylene glycol + 5% diclofenac sodium; group 3, calcium hydroxide paste with propylene glycol + 5% ibuprofen; group 4, calcium hydroxide paste with propylene glycol + 5% ciprofloxacin; and group 6, positive control (without medication). For analysis of the pH, the pastes were inserted into tubes and immersed in flasks containing ultrapure water. At the time intervals of 3, 24, 72, and 168 hours, the pH was measured with a calibrated pH meter. For microbial analysis, biofilm was induced in 30 bovine dentin blocks for 21 days. Subsequently, the pastes were placed on the blocks with biofilm for 7 days. Afterward, the pastes were removed by irrigation with sterile water, and the specimens were analyzed with a laser scanning confocal microscope with the 50 μL Live/Dead BacLight Bacterial Viability solution L7012 Kit (Molecular Probes, Inc, Eugene, OR). Data were subjected to statistical analysis at a significance level of 5%. The highest pH values were found for calcium hydroxide associated with ciprofloxacin in all periods analyzed. With the exception of pure calcium hydroxide paste, the other groups showed statistically significant differences (P < .05) in comparison with the positive control. The association of NSAIDs or antibiotic did not interfere with the pH of calcium hydroxide paste and increased the antimicrobial action of calcium hydroxide paste against Enterococcus faecalis biofilm formation. Published by Elsevier Inc.

Intercalation studies of zinc hydroxide chloride: Ammonia and amino acids

NASA Astrophysics Data System (ADS)

Arízaga, Gregorio Guadalupe Carbajal

2012-01-01

Zinc hydroxide chloride (ZHC) is a layered hydroxide salt with formula Zn5(OH)8Cl2·2H2O. It was tested as intercalation matrix for the first time and results were compared with intercalation products of the well-known zinc hydroxide nitrate and a Zn/Al layered double hydroxide. Ammonia was intercalated into ZHC, while no significant intercalation occurred in ZHN. Aspartic acid intercalation was only achieved by co-precipitation at pH=10 with ZHC and pH=8 with zinc hydroxide nitrate. Higher pH resistance in ZHC favored total deprotonation of both carboxylic groups of the Asp molecule. ZHC conferred more thermal protection against Asp combustion presenting exothermic peaks even at 452 °C while the exothermic event in ZHN was 366 °C and in the LDH at 276 °C.

Synthesis and adsorption properties of flower-like layered double hydroxide by a facile one-pot reaction with an eggshell membrane as assistant

NASA Astrophysics Data System (ADS)

Li, Songnan; Zhang, Jiawei; Jamil, Saba; Cai, Qinghai; Zang, Shuying

In this paper, flower-like layered double hydroxides were synthesized with eggshell membrane assistant. The as-prepared samples were characterized by a series of techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Thermal gravity-differential thermal analysis and Nitrogen sorption/desorption. The resulting layered double hydroxides were composed of nanoplates with edge-to-face particle interactions. The specific surface area and total pore volume of the as-prepared flower-like layered double hydroxides were 160m2/g and 0.65m3/g, respectively. The adsorption capacity of flower-like layered double hydroxides to Congo Red was 258mg/g, which was higher than that of layered double hydroxides synthesized by the traditional method.

Hydroxide Solvation and Transport in Anion Exchange Membranes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Chen; Tse, Ying-Lung Steve; Lindberg, Gerrick E.

Understanding hydroxide solvation and transport in anion exchange membranes (AEMs) can provide important insight into the design principles of these new membranes. To accurately model hydroxide solvation and transport, we developed a new multiscale reactive molecular dynamics model for hydroxide in aqueous solution, which was then subsequently modified for an AEM material. With this model, we investigated the hydroxide solvation structure and transport mechanism in the membrane. We found that a relatively even separation of the rigid side chains produces a continuous overlapping region for hydroxide transport that is made up of the first hydration shell of the tethered cationicmore » groups. Our results show that hydroxide has a significant preference for this overlapping region, transporting through it and between the AEM side chains with substantial contributions from both vehicular (standard diffusion) and Grotthuss (proton hopping) mechanisms. Comparison of the AEM with common proton exchange membranes (PEMs) showed that the excess charge is less delocalized in the AEM than the PEMs, which is correlated with a higher free energy barrier for proton transfer reactions. The vehicular mechanism also contributes considerably more than the Grotthuss mechanism for hydroxide transport in the AEM, while our previous studies of PEM systems showed a larger contribution from the Grotthuss mechanism than the vehicular mechanism for proton transport. The activation energy barrier for hydroxide diffusion in the AEM is greater than that for proton diffusion in PEMs, implying a more significant enhancement of ion transport in the AEM at elevated temperatures.« less

The effect of calcium hydroxide on the antibiotic component of Odontopaste and Ledermix paste.

PubMed

Athanassiadis, M; Jacobsen, N; Nassery, K; Parashos, P

2013-06-01

To investigate the chemical interaction of calcium hydroxide with the antibiotics demeclocycline calcium in Ledermix Paste and clindamycin hydrochloride in Odontopaste. Validated methods were developed to analyse the interaction of calcium hydroxide in two forms, Pulpdent and calcium hydroxide powder, with the two antibiotics. High-performance liquid chromatography (HPLC) was used to analyse the mixed samples of the pastes and calcium hydroxide. The concentration of demeclocycline calcium over 0-, 1-, 18-, 24-, 72-h and 7-day time-points was determined. The concentration of clindamycin hydrochloride over 1-, 6-, 24-, 72-h and 7-day time-points was determined. All tests with HPLC involved testing of the standard in duplicate alongside the samples. Linearity, precision and specificity of the testing procedures and apparatus were validated. Descriptive statistics are provided. The antibiotics in both Odontopaste and Ledermix Paste were affected by the addition of calcium hydroxide. When mixed with calcium hydroxide powder, Odontopaste had a 2% loss of clindamycin hydrochloride over 7 days, but when mixed with Pulpdent, there was a 36% loss over 7 days. Ledermix Paste showed an 80% loss of demeclocycline calcium over 7 days when mixed with calcium hydroxide powder and a 19% loss when mixed with Pulpdent over the 7-day period. The addition of calcium hydroxide to Odontopaste or Ledermix Paste results in reductions of the respective antibiotic over a 7-day time period. © 2012 International Endodontic Journal. Published by Blackwell Publishing Ltd.

Hydroxide Solvation and Transport in Anion Exchange Membranes.

PubMed

Chen, Chen; Tse, Ying-Lung Steve; Lindberg, Gerrick E; Knight, Chris; Voth, Gregory A

2016-01-27

Understanding hydroxide solvation and transport in anion exchange membranes (AEMs) can provide important insight into the design principles of these new membranes. To accurately model hydroxide solvation and transport, we developed a new multiscale reactive molecular dynamics model for hydroxide in aqueous solution, which was then subsequently modified for an AEM material. With this model, we investigated the hydroxide solvation structure and transport mechanism in the membrane. We found that a relatively even separation of the rigid side chains produces a continuous overlapping region for hydroxide transport that is made up of the first hydration shell of the tethered cationic groups. Our results show that hydroxide has a significant preference for this overlapping region, transporting through it and between the AEM side chains with substantial contributions from both vehicular (standard diffusion) and Grotthuss (proton hopping) mechanisms. Comparison of the AEM with common proton exchange membranes (PEMs) showed that the excess charge is less delocalized in the AEM than the PEMs, which is correlated with a higher free energy barrier for proton transfer reactions. The vehicular mechanism also contributes considerably more than the Grotthuss mechanism for hydroxide transport in the AEM, while our previous studies of PEM systems showed a larger contribution from the Grotthuss mechanism than the vehicular mechanism for proton transport. The activation energy barrier for hydroxide diffusion in the AEM is greater than that for proton diffusion in PEMs, implying a more significant enhancement of ion transport in the AEM at elevated temperatures.

Positive Active Material For Alkaline Electrolyte Storage Battert Nickel Electrodes

DOEpatents

Bernard, Patrick; Baudry, Michelle

2000-12-05

A method of manufacturing a positive active material for nickel electrodes of alkaline storage batteries which consists of particles of hydroxide containing mainly nickel and covered with a layer of a hydroxide phase based on nickel and yttrium is disclosed. The proportion of the hydroxide phase is in the range 0.15% to 3% by weight of yttrium expressed as yttrium hydroxide relative to the total weight of particles.

Synthesis, characterization, and evaluation of simple aluminum-based adsorbents for fluoride removal from drinking water.

PubMed

Du, Junyi; Sabatini, David A; Butler, Elizabeth C

2014-04-01

Simple aluminum (hydr)oxides and layered double hydroxides were synthesized using common chemicals and equipment by varying synthesis temperature, concentrations of extra sulfate and citrate, and metal oxide amendments. Aluminum (hydr)oxide samples were aged at either 25 or 200°C during synthesis and, in some cases, calcined at 600 °C. Despite yielding increased crystallinity and mineral phase changes, higher temperatures had a generally negative effect on fluoride adsorption. Addition of extra sulfate during synthesis of aluminum (hydr)oxides led to significantly higher fluoride adsorption capacity compared to aluminum (hydr)oxides prepared with extra citrate or no extra ligands. X-ray diffraction results suggest that extra sulfate led to the formation of both pseudoboehmite (γ-AlOOH) and basaluminite (Al4SO4(OH)10⋅4H2O) at 200 °C; energy dispersive X-ray spectroscopy confirmed the presence of sulfur in this solid. Treatment of aluminum (hydr)oxides with magnesium, manganese, and iron oxides did not significantly impact fluoride adsorption. While layered double hydroxides exhibited high maximum fluoride adsorption capacities, their adsorption capacities at dissolved fluoride concentrations close to the World Health Organization drinking water guideline of 1.5 mg L(-1) were much lower than those for the aluminum (hydr)oxides. Copyright © 2013 Elsevier Ltd. All rights reserved.

Arsenic removal from water

DOEpatents

Moore, Robert C [Edgewood, NM; Anderson, D Richard [Albuquerque, NM

2007-07-24

Methods for removing arsenic from water by addition of inexpensive and commonly available magnesium oxide, magnesium hydroxide, calcium oxide, or calcium hydroxide to the water. The hydroxide has a strong chemical affinity for arsenic and rapidly adsorbs arsenic, even in the presence of carbonate in the water. Simple and commercially available mechanical methods for removal of magnesium hydroxide particles with adsorbed arsenic from drinking water can be used, including filtration, dissolved air flotation, vortex separation, or centrifugal separation. A method for continuous removal of arsenic from water is provided. Also provided is a method for concentrating arsenic in a water sample to facilitate quantification of arsenic, by means of magnesium or calcium hydroxide adsorption.

Effect of ammonium hydroxide on ultrastructure and tenderness of buffalo meat.

PubMed

Naveena, B M; Kiran, M; Reddy, K Sudhakar; Ramakrishna, C; Vaithiyanathan, S; Devatkal, Suresh K

2011-08-01

This study was conducted with an objective to improve the tenderness of tough buffalo meat using ammonium hydroxide. Buffalo meat chunks from Biceps femoris muscle were marinated with distilled water (control), 0.1%, 0.5% and 1.0% solution of ammonium hydroxide for 48 h at 4±1 °C and subjected to various physico-chemical analysis and ultrastructural studies. Ammonium hydroxide increased (P<0.05) the pH, water holding capacity (WHC), collagen solubility, total and salt soluble protein extractability and cooking yield. Reduction (P<0.05) in Warner-Bratzler shear force values were observed in all ammonium hydroxide treated samples compared to non-treated control. Electrophoretic pattern of muscle proteins exhibited reduction in the intensity and number of certain protein bands for 0.1% and 0.5% ammonium hydroxide treated samples compared to control. Scanning and transmission electron microscopy also revealed breakdown of endothelium layers surrounding muscle fibers and weakening of Z-discs respectively, in treated samples compared to controls. These results suggest that ammonium hydroxide might be used to tenderize tough buffalo meat. Copyright © 2011 Elsevier Ltd. All rights reserved.

Calcium hydroxide suppresses Porphyromonas endodontalis lipopolysaccharide-induced bone destruction.

PubMed

Guo, J; Yang, D; Okamura, H; Teramachi, J; Ochiai, K; Qiu, L; Haneji, T

2014-05-01

Porphyromonas endodontalis and its main virulence factor, lipopolysaccharide (LPS), are associated with the development of periapical diseases and alveolar bone loss. Calcium hydroxide is commonly used for endodontic therapy. However, the effects of calcium hydroxide on the virulence of P. endodontalis LPS and the mechanism of P. endodontalis LPS-induced bone destruction are not clear. Calcium hydroxide rescued the P. endodontalis LPS-suppressed viability of MC3T3-E1 cells and activity of nuclear factor-κB (NF-κB) in these cells, resulting in the reduced expression of interleukin-6 and tumor necrosis factor-α. In addition, calcium hydroxide inhibited P. endodontalis LPS-induced osteoclastogenesis by decreasing the activities of NF-κB, p38, and ERK1/2 and the expression of nuclear factor of activated T-cell cytoplasmic 1 in RAW264.7 cells. Calcium hydroxide also rescued the P. endodontalis LPS-induced osteoclastogenesis and bone destruction in mouse calvaria. Taken together, our present results indicate that calcium hydroxide suppressed bone destruction by attenuating the virulence of P. endodontalis LPS on bone cells.

40 CFR 721.10018 - Calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Calcium hydroxide oxide silicate (Ca6... New Uses for Specific Chemical Substances § 721.10018 Calcium hydroxide oxide silicate (Ca6(OH)2O2... substance identified as calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3) (PMN P-01-442; CAS No. 13169...

40 CFR 721.10018 - Calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Calcium hydroxide oxide silicate (Ca6... New Uses for Specific Chemical Substances § 721.10018 Calcium hydroxide oxide silicate (Ca6(OH)2O2... substance identified as calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3) (PMN P-01-442; CAS No. 13169...

40 CFR 721.10018 - Calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Calcium hydroxide oxide silicate (Ca6... New Uses for Specific Chemical Substances § 721.10018 Calcium hydroxide oxide silicate (Ca6(OH)2O2... substance identified as calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3) (PMN P-01-442; CAS No. 13169...

40 CFR 721.10018 - Calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Calcium hydroxide oxide silicate (Ca6... New Uses for Specific Chemical Substances § 721.10018 Calcium hydroxide oxide silicate (Ca6(OH)2O2... substance identified as calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3) (PMN P-01-442; CAS No. 13169...

40 CFR 721.10018 - Calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Calcium hydroxide oxide silicate (Ca6... New Uses for Specific Chemical Substances § 721.10018 Calcium hydroxide oxide silicate (Ca6(OH)2O2... substance identified as calcium hydroxide oxide silicate (Ca6(OH)2O2(Si2O5)3) (PMN P-01-442; CAS No. 13169...

Rapeseed-straw enzymatic digestibility enhancement by sodium hydroxide treatment under ultrasound irradiation.

PubMed

Kang, Kyeong Eop; Jeong, Gwi-Taek; Park, Don-Hee

2013-08-01

In this study, we carried out sodium hydroxide and sonication pretreatments of rapeseed straw (Brassica napus) to obtain monosugar suitable for production of biofuels. To optimize the pretreatment conditions, we applied a statistical response-surface methodology. The optimal pretreatment conditions using sodium hydroxide under sonication irradiation were determined to be 75.0 °C, 7.0 % sodium hydroxide, and 6.8 h. For these conditions, we predicted 97.3 % enzymatic digestibility. In repeated experiments to validate the predicted value, 98.9 ± 0.3 % enzymatic digestibility was obtained, which was well within the range of the predicted model. Moreover, sonication irradiation was found to have a good effect on pretreatment in the lower temperature range and at all concentrations of sodium hydroxide. According to scanning electron microscopy images, the surface area and pore size of the pretreated rapeseed straw were modified by the sodium hydroxide pretreatment under sonication irradiation.

Influence of different desapping agents on the incidence of sapburn, ripening behaviour and quality of mango.

PubMed

Barman, Kalyan; Asrey, Ram; Pal, R K; Jha, S K; Sharma, Swati

2015-01-01

Sapburn injury in mango is regarded as the most serious problem as it reduces the aesthetic appeal and downgrade the fruit quality with considerable economic losses. For the control of sapburn injury, physiologically mature mango fruits of cv. Chausa were harvested along with 5-8 cm stalk attached. Immediately after harvesting, fruits were de-stemmed and treated with different desapping agent solutions [calcium hydroxide (1 %), sodium hydroxide (1 %), alum (0.5 and 1 %)] by dipping them for 5 min. In control fruits, the pedicels were removed and sap was allowed to spread freely over the fruit surface. After treatment application, fruits were air-dried and stored at ambient condition (30 ± 2 °C) for 12 days. Among the treatments, fruits desapped with sodium hydroxide (1 %) showed significantly lower (7.6-fold) sapburn injury followed by alum (0.5 %) treatment than control. Respiration and ethylene evolution rates were also significantly suppressed and delayed with sodium hydroxide (1 %) treatment. Fruit firmness and functional properties like, antioxidant capacity, total carotenoids and total phenolics content were also found higher in sodium hydroxide (1 %) treated fruits. Pectin methyl esterase and polygalacturonase enzyme activity were recorded higher in fruits of control and calcium hydroxide treatment however; it was suppressed by sodium hydroxide and alum treatments. Fruit quality parameters like color, total soluble solids, titratable acidity and total sugars content were found higher in calcium hydroxide and sodium hydroxide treated fruits than control and alum treated fruits.

Study of nickel hydroxide electrodes. 2: Oxidation products of nickel (2) hydroxides

NASA Technical Reports Server (NTRS)

Bode, H.; Demelt, K.; White, J.

1986-01-01

Pure phases of some oxidized Ni oxides were prepared galvanimetrically with the Ni(2) hydroxide electrode of an alkaline battery. The crystallographic data of these phases, their chemical behavior, and conditions of transition were studied.

System for removal of arsenic from water

DOEpatents

Moore, Robert C.; Anderson, D. Richard

2004-11-23

Systems for removing arsenic from water by addition of inexpensive and commonly available magnesium oxide, magnesium hydroxide, calcium oxide, or calcium hydroxide to the water. The hydroxide has a strong chemical affinity for arsenic and rapidly adsorbs arsenic, even in the presence of carbonate in the water. Simple and commercially available mechanical systems for removal of magnesium hydroxide particles with adsorbed arsenic from drinking water can be used, including filtration, dissolved air flotation, vortex separation, or centrifugal separation. A system for continuous removal of arsenic from water is provided. Also provided is a system for concentrating arsenic in a water sample to facilitate quantification of arsenic, by means of magnesium or calcium hydroxide adsorption.

Layered double hydroxide stability. 1. Relative stabilities of layered double hydroxides and their simple counterparts

NASA Technical Reports Server (NTRS)

Boclair, J. W.; Braterman, P. S.

1999-01-01

Solutions containing di- and trivalent metal chlorides [M(II) = Mg2+, Zn2+, Co2+, Ni2+, Mn2+; M(III) = Al3+, Fe3+] were titrated with NaOH to yield hydrotalcite-like layered double hydroxides (LDH), [[M(II)]1-x[M(III)]x(OH)2][Cl]x yH2O, by way of M(III) hydroxide/hydrous oxide intermediates. Analysis of the resultant titration curves yields nominal solubility constants for the LDH. The corresponding LDH stabilities are in the order Mg < Mn < Co approximately Ni < Zn for M(II) and Al < Fe for M(III). The stability of LDH relative to the separate metal hydroxides/hydrous oxides is discussed.

Conversion coatings prepared or treated with calcium hydroxide solutions

NASA Technical Reports Server (NTRS)

Maxey, Jason (Inventor); Nelson, Carl (Inventor); Eylem, Cahit (Inventor); Minevski, Zoran (Inventor); Clarke, Eric (Inventor)

2002-01-01

A conversion coating process that forms a stable and corrosion-resistant oxide layer on metal or metal oxide substrates or layers. Particularly, the conversion coating process involves contacting the metal or metal oxide substrate or layer with the aqueous calcium hydroxide solutions in order to convert the surface of the substrate to a stable metal oxide layer or coating. According to the present invention, the calcium hydroxide solution is prepared by removing carbon dioxide from water or an aqueous solution before introducing the calcium hydroxide. In this manner, formation of calcium carbonate particles is avoided and the porosity of the conversion coating produced by the calcium hydroxide solution is reduced to below about 1%.

The effect of calcium hydroxide on the steroid component of Ledermix and Odontopaste.

PubMed

Athanassiadis, M; Jacobsen, N; Parashos, P

2011-12-01

To investigate the chemical interaction of calcium hydroxide with the corticosteroid triamcinolone acetonide in Ledermix Paste and in Odontopaste, a new steroid/antibiotic paste. Validated methods were developed to analyse the interaction of calcium hydroxide in two forms, Pulpdent Paste and calcium hydroxide powder, with triamcinolone acetonide within Odontopaste and Ledermix Paste. High-performance liquid chromatography (HPLC) was used to analyse the mixed samples of the pastes and calcium hydroxide. The concentration of triamcinolone acetonide within the pastes was determined over 0, 2, 6, 24 and 72-h time-points. All tests with the HPLC involved the testing of the standard with triplicate injections alongside the samples. All samples were tested in duplicate with each injected twice; therefore, four tests were performed for each investigation. Linearity, precision and specificity of the testing procedures and apparatus were validated. Descriptive statistics are provided. In both pastes, there was a marked rapid destruction of the triamcinolone acetonide steroid upon mixing with calcium hydroxide. Odontopaste suffered a lower rate of destruction of the triamcinolone acetonide component than Ledermix Paste, but both pastes showed very similar degrees of steroid destruction after 72 h. When using calcium hydroxide powder with Ledermix Paste, the triamcinolone was destroyed entirely and immediately. The addition of calcium hydroxide to Odontopaste or Ledermix Paste results in the rapid destruction of the steroid. © 2011 International Endodontic Journal.

Study on improving the heat storage property of Ba(OH)2·8H2O with paraffin

NASA Astrophysics Data System (ADS)

Cui, Kaixuan; Liu, Liqiang; Sun, Mingjie

2017-12-01

Barium hydroxide octahydrate is the crystalline hydration salt with the highest latent heat density within the phase change temperature interval of 0-120 °C and it has a broad application prospect as a phase-change material (PCM). Firstly, red copper test tube was used for the melting—solidification heat cycle experiment in this paper, which was verified by the corrosion experiment of barium hydroxide solution. After the thermogravimetric analysis, it is found that paraffin can effectively reduce the evaporation escape of barium hydroxide octahydrate crystal water within 100 °C. Repeated heat cycle experiments indicated that the paraffin with larger coverage mass fraction can reduce the inhibiting effect of barium hydroxide octahydrate crystal water more obviously. X-ray diffraction analysis indicated that the phase composition of the barium hydroxide octahydrate sample covered with 50 wt% paraffin nearly had no change, while the sample not covered with paraffin has the weight loss ratio of 34.67% and reacted with CO2 in the air, generating BaCO3. In summary, paraffin can not only inhibit the evaporation of crystal water, but also effectively isolate the air to prevent barium hydroxide octahydrate from denaturation. This greatly improved the practicability of barium hydroxide octahydrate as a PCM, laying a good foundation for the further application of barium hydroxide octahydrate.

Layered zinc hydroxide salts: delamination, preferred orientation of hydroxide lamellae, and formation of ZnO nanodiscs.

PubMed

Demel, Jan; Pleštil, Josef; Bezdička, Petr; Janda, Pavel; Klementová, Mariana; Lang, Kamil

2011-08-15

Delamination of layered zinc hydroxide salts (LZH) into hydroxide layers provides nanobuilding blocs of a two-dimensional anisotropy. The methodology, extent of delamination, the size and stability of hydroxide lamellae are described in detail. The ability of lamellae to restack to form oriented hydroxide films depends on the solvent, original LZH salt, and conditions used for delamination. The most interesting results were obtained using LZH intercalated with dodecyl sulfate anions and LZH nitrate delaminated in butanol at 60 °C and in formamide at room temperature, respectively. The former method produces hydroxide lamellae of a lateral size of ca. 10-20 nm. The inner structure of the hydroxide layers is conserved and separated lamellae restack to the original layered structure of LZH dodecyl sulfate. The latter method yields lamellae with a size decreasing from 73.3 nm to 10 nm after a 2-week aging, while their thickness is nearly constant (2.6-3.8 nm). However, the use of formamide is complicated by the formation of Zn(II) formate. The major part of LZH intercalated with dodecyl sulfate anions is transformed during the delamination procedure to anisotropic ZnO nanoparticles, either needle-like particles prolonged in the [0 0 1] direction or disc-like particles flattened along the (0 0 1) plane. Copyright © 2011 Elsevier Inc. All rights reserved.

Anodes for alkaline electrolysis

DOEpatents

Soloveichik, Grigorii Lev [Latham, NY

2011-02-01

A method of making an anode for alkaline electrolysis cells includes adsorption of precursor material on a carbonaceous material, conversion of the precursor material to hydroxide form and conversion of precursor material from hydroxide form to oxy-hydroxide form within the alkaline electrolysis cell.

21 CFR 331.11 - Listing of specific active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... aluminosilicates. (4) Magnesium carbonate. (5) Magnesium glycinate. (6) Magnesium hydroxide. (7) Magnesium oxide..., aluminum hydroxide-magnesium carbonate codried gel, aluminum hydroxide-magnesium trisilicate codried gel... or salt; maximum daily dosage limit 8 grams. (f) Glycine (aminoacetic acid). (g) Magnesium-containing...

21 CFR 331.11 - Listing of specific active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... aluminosilicates. (4) Magnesium carbonate. (5) Magnesium glycinate. (6) Magnesium hydroxide. (7) Magnesium oxide..., aluminum hydroxide-magnesium carbonate codried gel, aluminum hydroxide-magnesium trisilicate codried gel... or salt; maximum daily dosage limit 8 grams. (f) Glycine (aminoacetic acid). (g) Magnesium-containing...

Pretreatment of poly(l-lactide-co-glycolide) scaffolds with sodium hydroxide enhances osteoblastic differentiation and slows proliferation of mouse preosteoblast cells.

PubMed

Carpizo, Katherine H; Saran, Madeleine J; Huang, Weibiao; Ishida, Kenji; Roostaeian, Jason; Bischoff, David; Huang, Catherine K; Rudkin, George H; Yamaguchi, Dean T; Miller, Timothy A

2008-02-01

Surface topography is important in the creation of a scaffold for tissue engineering. Chemical etching of poly(l-lactide-co-glycolide) with sodium hydroxide has been shown to enhance adhesion and function of numerous cell types. The authors investigated the effects of sodium hydroxide pretreatment of three-dimensional poly(l-lactide-co-glycolide) scaffolds on the adhesion, differentiation, and proliferation of MC3T3-E1 murine preosteoblasts. MC3T3-E1 cells were seeded onto three-dimensional poly(l-lactide-co-glycolide) scaffolds with and without 1 M sodium hydroxide pretreatment. Cells were then cultured in osteogenic medium and harvested at varying time points for RNA extraction. Quantitative real-time reverse-transcriptase polymerase chain reaction was performed to measure mRNA expression of several osteogenic marker genes. In addition, cell numbers were determined at varying time points during the culture period. All experiments were performed in triplicate. Pretreatment of three-dimensional poly(l-lactide-co-glycolide) scaffolds with sodium hydroxide resulted in statistically significant up-regulation of mRNA expression of alkaline phosphatase, bone sialoprotein, osteocalcin, and vascular endothelial growth factor during the first 10 days of culture. Histologic analysis demonstrated a striking increase in mineralized cell matrix deposition in the sodium hydroxide-treated group. Cell number was statistically higher in the sodium hydroxide-treated group immediately after cell seeding, suggesting improved adhesion. During the first 24 hours of culture, cells grew faster in the control group than in the sodium hydroxide-treated group. Chemical etching of poly(l-lactide-co-glycolide) scaffolds with sodium hydroxide strongly influences the behavior of MC3T3-E1 preosteoblasts in vitro by enhancing adhesion and differentiation and slowing proliferation. Sodium hydroxide treatment may represent a simple and inexpensive way of improving scaffolds for use in bone tissue engineering.

Structural Differentiation between Layered Single (Ni) and Double Metal Hydroxides (Ni–Al LDHs) Using Wavelet Transformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siebecker, Matthew G.; Sparks, Donald L.

2017-09-07

Layered double hydroxides (LDHs) are anionic clays important in disciplines such as environmental chemistry, geochemistry, and materials science. Developments in signal processing of extended X-ray absorption fine structure (EXAFS) data, such as wavelet transformation (WT), have been used to identify transition metals and Al present in the hydroxide sheets of LDHs. The WT plots of LDHs should be distinct from those of isostructural single metal hydroxides. However, no direct comparison of these minerals appears in the literature using WT. This work systematically analyzes a suite of Ni-rich mineral standards, including Ni–Al LDHs, single metal Ni hydroxides, and Ni-rich silicates usingmore » WT. The results illustrate that the WT plots for α-Ni(OH)2 and Ni–Al LDHs are often indistinguishable from each other, with similar two-component plots for the different mineral types. This demonstrates that the WT of the first metal shell often cannot be used to differentiate an LDH from a single metal hydroxide. Interlayer anions adsorbed to the hydroxide sheet of α-Ni(OH)2 affect the EXAFS spectra and are not visible in the FT but are clearly resolved and discrete in the WT.« less

Chemical matricectomy with sodium hydroxide: long-term follow-up results.

PubMed

Bostanci, Seher; Kocyigit, Pelin; Parlak, Nehir; Gungor, Hilayda Karakok

2014-11-01

Chemical matricectomy with sodium hydroxide is a method being used successfully in the treatment of ingrown toenail. In this study, it was aimed to evaluate long-term recurrence rates after chemical matricectomy using sodium hydroxide application of different durations. Two hundred two patients with ingrown nail edges were treated with either 1-minute (Group 1) or 2-minute (Group 2) applications of sodium hydroxide matricectomy. All patients were followed for at least 2 years. Chemical matricectomy with sodium hydroxide was applied to a total of 585 nail edges of 202 cases. The overall recurrence rates in Group 1 and Group 2 were 6.4% and 7.1%, respectively, during the average 7.5-year follow-up period. No statistically significant differences were detected in terms of recurrence between the 2 groups (p = .73). Chemical matricectomy with sodium hydroxide is an easy method in the treatment of ingrown nails, with low morbidity and high success rates. There was no difference between 1-minute and 2-minute applications in terms of recurrence during the long-term follow-up. Chemical matricectomy with 1-minute application of sodium hydroxide showed high success in terms of long-term follow-up results.

Method of determining pH by the alkaline absorption of carbon dioxide

DOEpatents

Hobbs, David T.

1992-01-01

A method for measuring the concentration of hydroxides in alkaline solutions in a remote location using the tendency of hydroxides to absorb carbon dioxide. The method includes the passing of carbon dioxide over the surface of an alkaline solution in a remote tank before and after measurements of the carbon dioxide solution. A comparison of the measurements yields the absorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to absorption fraction.

Method of treating inflammatory diseases using a radiolabeled ferric hydroxide calloid

DOEpatents

Atcher, Robert W.; Hines, John J.

1992-01-01

A ferric hydroxide colloid having an alpha-emitting radionuclide essentially on the outer surfaces and a method of forming same. The method includes oxidizing a ferrous hydroxide to ferric hydroxide in the presence of a preselected radionuclide to form a colloid having the radionuclide on the outer surface thereof, and thereafter washing the colloid, and suspending the washed colloid in a suitable solution. The labelled colloid is useful in cancer therapy and for the treatment of inflamed joints.

Nickel hydroxide/cobalt-ferrite magnetic nanocatalyst for alcohol oxidation.

PubMed

Bhat, Pooja B; Inam, Fawad; Bhat, Badekai Ramachandra

2014-08-11

A magnetically separable, active nickel hydroxide (Brønsted base) coated nanocobalt ferrite catalyst has been developed for oxidation of alcohols. High surface area was achieved by tuning the particle size with surfactant. The surface area of 120.94 m2 g(-1) has been achieved for the coated nanocobalt ferrite. Improved catalytic activity and selectivity were obtained by synergistic effect of transition metal hydroxide (basic hydroxide) on nanocobalt ferrite. The nanocatalyst oxidizes primary and secondary alcohols efficiently (87%) to corresponding carbonyls in good yields.

Neutralization of Hydroxide Ion in Melt-Grown NaCl Crystals

NASA Technical Reports Server (NTRS)

Otterson, Dumas A.

1961-01-01

Many recent studies of solid-state phenomena, particularly in the area of crystal imperfections, have involved the use of melt-grown NaCl single crystals. Quite often trace impurities in these materials have had a prominent effect on these phenomena. Trace amounts of hydroxide ion have been found in melt-grown NaCl crystals. This paper describes a nondestructive method of neutralizing the hydroxide ion in such crystals. Crystals of similar hydroxide content are maintained at an elevated temperature below the melting point of NaCl in a flowing atmosphere containing. dry hydrogen chloride. Heat treatment is continued until an analysis of the test specimens shows no excess hydroxide ion. A colorimetric method previously described4 is used for this analysis.

The effects of lithium hydroxide solution on alkali silica reaction gels created with opal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitchell, Lyndon D.; Beaudoin, James J.; Grattan-Bellew, Patrick

The reaction of Nevada opal with calcium hydroxide, potassium hydroxide and lithium hydroxide solutions was investigated. In addition, opal was exposed to a combined solution of these three hydroxides. The progress of the three reactions was followed using X-ray diffraction (XRD), {sup 29}Si nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM). The XRD results indicated the presence of a low-angle peak exclusive to the lithium-based reactions. The NMR results suggested a change in the silicate structure in the presence of lithium. These techniques indicated that the reaction of the alkali with the opal starting material is inhibited and perhapsmore » stopped in the presence of lithium hydroxide. SEM revealed that the morphology of the reaction products on the surface of the reacted opal grains is markedly different invariably. It was concluded that evidence to support the theory of a protective layer exists and that the nature of the layer varies with ion type.« less

Mixing Acid Salts and Layered Double Hydroxides in Nanoscale under Solid Condition

PubMed Central

Nakayama, Hirokazu; Hayashi, Aki

2014-01-01

The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution. However, no intercalation was achieved for sorbic acid. Although intercalation of sorbate and aspartate into chloride-type layered double hydroxide was possible, the uptakes for these intercalation compounds were lower than those obtained using nitrate-type layered double hydroxide. The intercalation under solid condition could be achieved to the same extent as for ion-exchange reaction in aqueous solution, and the reactivity was similar to that observed in aqueous solution. This method will enable the encapsulation of acidic drug in layered double hydroxide as nano level simply by mixing both solids. PMID:25080007

Mixing Acid Salts and Layered Double Hydroxides in Nanoscale under Solid Condition.

PubMed

Nakayama, Hirokazu; Hayashi, Aki

2014-07-30

The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution. However, no intercalation was achieved for sorbic acid. Although intercalation of sorbate and aspartate into chloride-type layered double hydroxide was possible, the uptakes for these intercalation compounds were lower than those obtained using nitrate-type layered double hydroxide. The intercalation under solid condition could be achieved to the same extent as for ion-exchange reaction in aqueous solution, and the reactivity was similar to that observed in aqueous solution. This method will enable the encapsulation of acidic drug in layered double hydroxide as nano level simply by mixing both solids.

Associating cooking additives with sodium hydroxide to pretreat bamboo residues for improving the enzymatic saccharification and monosaccharides production.

PubMed

Huang, Caoxing; He, Juan; Wang, Yan; Min, Douyong; Yong, Qiang

2015-10-01

Cooking additive pulping technique is used in kraft mill to increase delignification degree and pulp yield. In this work, cooking additives were firstly applied in the sodium hydroxide pretreatment for improving the bioconversion of bamboo residues to monosaccharides. Meanwhile, steam explosion and sulfuric acid pretreatments were also carried out on the sample to compare their impacts on monosaccharides production. Results indicated that associating anthraquinone with sodium hydroxide pretreatment showed the best performance in improving the original carbohydrates recovery, delignification, enzymatic saccharification, and monosaccharides production. After consecutive pretreatment and enzymatic saccharification process, 347.49 g, 307.48 g, 142.93 g, and 87.15 g of monosaccharides were released from 1000 g dry bamboo residues pretreated by sodium hydroxide associating with anthraquinone, sodium hydroxide, steam explosion and sulfuric acid, respectively. The results suggested that associating cooking additive with sodium hydroxide is an effective pretreatment for bamboo residues to enhance enzymatic saccharification for monosaccharides production. Copyright © 2015 Elsevier Ltd. All rights reserved.

Formation of iron (hydr)oxides during the abiotic oxidation of Fe(II) in the presence of arsenate.

PubMed

Song, Jia; Jia, Shao-Yi; Yu, Bo; Wu, Song-Hai; Han, Xu

2015-08-30

Abiotic oxidation of Fe(II) is a common pathway in the formation of Fe (hydr)oxides under natural conditions, however, little is known regarding the presence of arsenate on this process. In hence, the effect of arsenate on the precipitation of Fe (hydr)oxides during the oxidation of Fe(II) is investigated. Formation of arsenic-containing Fe (hydr)oxides is constrained by pH and molar ratios of As:Fe during the oxidation Fe(II). At pH 6.0, arsenate inhibits the formation of lepidocrocite and goethite, while favors the formation of ferric arsenate with the increasing As:Fe ratio. At pH 7.0, arsenate promotes the formation of hollow-structured Fe (hydr)oxides containing arsenate, as the As:Fe ratio reaches 0.07. Arsenate effectively inhibits the formation of magnetite at pH 8.0 even at As:Fe ratio of 0.01, while favors the formation of lepidocrocite and green rust, which can be latterly degenerated and replaced by ferric arsenate with the increasing As:Fe ratio. This study indicates that arsenate and low pH value favor the slow growth of dense-structured Fe (hydr)oxides like spherical ferric arsenate. With the rapid oxidation rate of Fe(II) at high pH, ferric (hydr)oxides prefer to precipitate in the formation of loose-structured Fe (hydr)oxides like lepidocrocite and green rust. Copyright © 2015 Elsevier B.V. All rights reserved.

21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Alumina (dried aluminum hydroxide). 73.1010 Section 73.1010 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...) Specifications. Alumina (dried aluminum hydroxide) shall conform to the following specifications: Acidity or...

Method of purifying isosaccharinate

DOEpatents

Rai, Dhanpat; Moore, Robert C.; Tucker, Mark D.

2010-09-07

A method of purifying isosaccharinate by mixing sodium carbonate, potassium carbonate, sodium hydroxide or potassium hydroxide with calcium isosaccharinate, removing the precipitated calcium carbonate and adjusting the pH to between approximately 4.5 to 5.0 thereby removing excess carbonate and hydroxide to provide an acidic solution containing isosaccharinate.

21 CFR 73.1326 - Chromium hydroxide green.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Chromium hydroxide green. 73.1326 Section 73.1326 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1326 Chromium hydroxide green. (a) Identity. (1...

21 CFR 73.1326 - Chromium hydroxide green.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Chromium hydroxide green. 73.1326 Section 73.1326 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1326 Chromium hydroxide green. (a) Identity. (1...

21 CFR 73.1326 - Chromium hydroxide green.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Chromium hydroxide green. 73.1326 Section 73.1326 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1326 Chromium hydroxide green. (a) Identity. (1...

BIOGEOCHEMICAL PROCESSES CONTROLLING ARSENIC SPECIATION AND BIOTRANSFORMATION IN GRANULAR FERRIC HYDROXIDE COATED SAND

EPA Science Inventory

Arsenic mobilization from solid phase Fe (III) hydroxides is an issue of concern, as water-borne arsenic can migrate into pristine environments, endangering aquatic and human life. In general, metal oxide (hydroxides) exerts a dominating effect on the fate and transport of arseni...

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow...

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow...

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow...

Method of determining pH by the alkaline absorption of carbon dioxide

DOEpatents

Hobbs, D.T.

1992-10-06

A method is described for measuring the concentration of hydroxides in alkaline solutions in a remote location using the tendency of hydroxides to absorb carbon dioxide. The method includes the passing of carbon dioxide over the surface of an alkaline solution in a remote tank before and after measurements of the carbon dioxide solution. A comparison of the measurements yields the absorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to absorption fraction. 2 figs.

Complications of sodium hydroxide chemical matrixectomy: nail dystrophy, allodynia, hyperalgesia.

PubMed

Bostancı, Seher; Koçyiğit, Pelin; Güngör, Hilayda Karakök; Parlak, Nehir

2014-11-01

Ingrown toenails are seen most commonly in young adults, and they can seriously affect daily life. Partial nail avulsion with chemical matrixectomy, generally by using either sodium hydroxide or phenol, is one of the most effective treatment methods. Known complications of phenol matrixectomy are unpredictable tissue damage, prolonged postoperative drainage, increased secondary infection rates, periostitis, and poor cosmetic results. To our knowledge, there have been no reports about the complications related to sodium hydroxide matrixectomy. Herein, we describe three patients who developed nail dystrophy, allodynia, and hyperalgesia after sodium hydroxide matrixectomy.

Detection of interstellar sodium hydroxide in self-absorption toward the galactic center

NASA Technical Reports Server (NTRS)

Hollis, J. M.; Rhodes, P. J.

1982-01-01

A weak self-absorbed emission line, which is identified as the J = 4-3 transition of sodium hydroxide, has been detected in the direction of Sgr B2(OH). The correspondingly weak Sgr B2(QH) emission line U75406, previously reported as an unidentified spectral feature by other investigators, is consistent with the J = 3-2 transition of sodium hydroxide. This detection may represent the first evidence of a grain reaction formation mechanism for simple metal hydroxides. The detection of H62 Delta toward Orion A is also reported.

Synthesis and structure of [Na11(OtBu)10(OH)]: 1H NMR shift of a hydroxide ion encapsulated in a 21-vertex alcoholate cage.

PubMed

Geier, Jens; Grützmacher, Hansjörg

2003-12-07

[Na11(OtBu)10(OH)], a hydroxide enclosing 21-vertex cage compound, was found to crystallize from mixtures of sodium tert.butanolate with sodium hydroxide. Its structure can be derived from the known (NaOtBu)6-hexaprismane by replacing one butanolate unit with OH- and capping the latter with five additional units of NaOtBu. The hydroxide shows a signal at -3.21 ppm in the 1H NMR spectrum.

Rapid Production of Mixed-Base Hydrogen Peroxide by Direct-Contact Liquefied Nitrogen Evaporation; Process Design, Scale-Up, and Validation

DTIC Science & Technology

2004-01-01

phase in November 1996. 1-2. BASIC HYDROGEN PEROXIDE In the early COIL work, either potassium hydroxide (KOH) or sodium hydroxide (NaOH) was the base of...the candidate refrigerants include: R22, R404a, R134a, carbon dioxide, and ammonia. 2-3-3. Surface Evaporator To improve the heat transfer efficiency...monohydrate (LiOH.H20), sodium hydroxide (NaOH), and potassium hydroxide (KOH). The use of solids allows numerous variations of blending sequence and heat

On the Nickel Hydroxide Electrode. I. On Nickel (II) Hydroxide Hydrate,

DTIC Science & Technology

1980-10-27

1 - 4.60 A), and the hydrous form is halloysite , AI 2Si2 O5 (OH)4 .2H20 with d001 - 10.25 A (analogous to a-3Ni(OH)2 .2H20 with do01 - 8.07 A). On...heating of halloysite , the entire intermediate layer water is lost at about 1500 C, as for a nickel hydroxide, without the hydroxide layer separation...significantly reducing to meta- halloysite . 13 The conversion of the a form under the influence of alkali goes only in one direction. This monotropic

Green Rust: Its Electrochemical Generation, Characterization, and Implications

DTIC Science & Technology

2009-02-01

FeOOH), and lepidocrocite ( γ -FeOOH) in well-aerated systems, and hematite (α- Fe2O3 ) maghemite (δ- Fe2O3 ) or magnetite (Fe3O4) in oxygen-depleted...ferric hydroxides that belong to a family of minerals known as layered double hydroxides ( LDH ). Its general formula is [FeII(6-x) FeIIIx (OH)12]x+[Ax...of ferrous and ferric hydroxides that belong to a family of minerals known as layered double hydroxides ( LDH ). Its general formula is [FeII (6-x) FeIII

Ni/metal hydride secondary element

DOEpatents

Bauerlein, Peter

2005-04-19

A Ni/metal hydride secondary element having a positive nickel hydroxide electrode, a negative electrode having a hydrogen storage alloy, and an alkaline electrolyte, the positive electrode, provided with a three-dimensional metallic conductive structure, also contains an aluminum compound which is soluble in the electrolyte, in addition to nickel hydroxide and cobalt oxide. The aluminum compound is aluminum hydroxide and/or aluminum oxide, and the mass of the aluminum compound which is present in the positive bulk material mixture is 0.1 to 2% by weight relative to the mass of the nickel hydroxide which is present. In combination with aluminum hydroxide or aluminum oxide, the positive electrode further contains lanthanoid oxidic compounds Y.sub.2 O.sub.3, La.sub.2 O.sub.3 and Ca(OH).sub.2, as well as mixtures of these compounds.

Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

NASA Astrophysics Data System (ADS)

de Oliveira, Henrique Bortolaz; Wypych, Fernando

2016-11-01

Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO42-/g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO42-/g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated.

Enhancing the antibacterial activity of the gold standard intracanal medicament with incorporation of silver zeolite: An in vitro study.

PubMed

Ghatole, Kiran; Gowdra, Ramesh Halebathi Giriyappa; Azher, Samer; Sabharwal, Sumit; Singh, Veerandar T; Sundararajan, Bharath Vardhana

2016-01-01

Enterococcus faecalis is a persistent organism that plays a major role in the etiology of persistent periradicular lesions after root canal treatment has been associated with different forms of periradicular disease including primary endodontic infections and persistent infections. The present study compares the antibacterial activities of calcium hydroxide, calcium hydroxide mixed with silver zeolite, and calcium hydroxide mixed with 2% chlorhexidine against E. faecalis using direct contact test. The test materials of the in vitro experimental study were grouped as group 1-calcium hydroxide mixed with sterile water, group 2-2% silver zeolite added in calcium hydroxide mixed with sterile water, and group 3-calcium hydroxide mixed with 2% chlorhexidine. The bottom of microtiter plate were coated with freshly mixed tested material and a 10 μL of bacterial suspension was placed. After 1 h of incubation at 37°C, brain-heart infusion (BHI) broth (245 μL) was added and mixed for 2 min. These were designated as "subgroup 1" wells. A volume of 15 μL of broth then transferred from subgroup 1 wells to an adjacent set of four wells containing fresh BHI medium (215 μL); these wells were designated as "subgroup 2"' wells. The optical density was measured by a spectrophotometer after the first day, third day, and seventh day. One-way analysis of variance (ANOVA) and Tukey tests were performed for the analysis. Calcium hydroxide mixed with silver zeolite showed maximum antibacterial activity. Silver zeolite can be added in calcium hydroxide to enhance the latter's antibacterial activity against E. faecalis.

Treatment of As(V) and As(III) by electrocoagulation using Al and Fe electrode.

PubMed

Kuan, W H; Hu, C Y; Chiang, M C

2009-01-01

A batch electrocoagulation (EC) process with bipolar electrode and potentiodynamic polarization tests with monopolar systems were investigated as methods to explore the effects of electrode materials and initial solution pH on the As(V) and As(III) removal. The results displayed that the system with Al electrode has higher reaction rate during the initial period from 0 to 25 minutes than that of Fe electrode for alkaline condition. The pH increased with the EC time because the As(V) and As(III) removal by either co-precipitation or adsorption resulted in that the OH positions in Al-hydroxide or Fe-hydroxide were substituted by As(V) and As(III). The pH in Fe electrode system elevate higher than that in Al electrode because the As(V) removal substitutes more OH position in Fe-hydroxide than that in Al-hydroxide. EC system with Fe electrode can successfully remove the As(III) but system with Al electrode cannot because As(III) can strongly bind to the surface of Fe-hydroxide with forming inner-sphere species but weakly adsorb to the Al-hydroxide surface with forming outer-sphere species. The acidic solution can destroy the deposited hydroxide passive film then allow the metallic ions liberate into the solution, therefore, the acidic initial solution can enhance the As(V) and As(III) removal. The over potential calculation and potentiodynamic polarization tests reveal that the Fe electrode systems possess higher over potential and pitting potential than that of Al electrode system due to the fast hydrolysis of and the occurrence of Fe-hydroxide passive film.

Effect of ferric hydroxide suspension on blood chemstry in the common shiner, Notropus cornutus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brenner, F.J.; Corbett, S.; Shertzer, R.

1976-05-01

Common shiners, Notropus cornutus, were exposed to 3 ppM ferric hydroxide for periods from two to eight weeks. Ferric hydroxide resulted in initial changes in serum protein, glucose, Na and K ions, but these changes did not adversely affect the internal dynamics of the fish.

A facile one-pot synthesis of ruthenium hydroxide nanoparticles on magnetic silica: Aqueous hydration of nitriles to amides

EPA Science Inventory

One-pot synthesis of ruthenium hydroxide nanoparticles on magnetic silica is described which involve the in situ generation of magnetic silica (Fe3O4@ SiO2) and ruthenium hydroxide immobilization; the hydration of nitriles occurs in high yield and excellent selectivity using this...

Vibrational dynamics of aqueous hydroxide solutions probed using broadband 2DIR spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mandal, Aritra; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139; Tokmakoff, Andrei, E-mail: tokmakoff@uchicago.edu

2015-11-21

We employed ultrafast transient absorption and broadband 2DIR spectroscopy to study the vibrational dynamics of aqueous hydroxide solutions by exciting the O–H stretch vibrations of the strongly hydrogen-bonded hydroxide solvation shell water and probing the continuum absorption of the solvated ion between 1500 and 3800 cm{sup −1}. We observe rapid vibrational relaxation processes on 150–250 fs time scales across the entire probed spectral region as well as slower vibrational dynamics on 1–2 ps time scales. Furthermore, the O–H stretch excitation loses its frequency memory in 180 fs, and vibrational energy exchange between bulk-like water vibrations and hydroxide-associated water vibrations occursmore » in ∼200 fs. The fast dynamics in this system originate in strong nonlinear coupling between intra- and intermolecular vibrations and are explained in terms of non-adiabatic vibrational relaxation. These measurements indicate that the vibrational dynamics of the aqueous hydroxide complex are faster than the time scales reported for long-range transport of protons in aqueous hydroxide solutions.« less

Nickel hydroxides and related materials: a review of their structures, synthesis and properties

PubMed Central

Hall, David S.; Lockwood, David J.; Bock, Christina; MacDougall, Barry R.

2015-01-01

This review article summarizes the last few decades of research on nickel hydroxide, an important material in physics and chemistry, that has many applications in engineering including, significantly, batteries. First, the structures of the two known polymorphs, denoted as α-Ni(OH)2 and β-Ni(OH)2, are described. The various types of disorder, which are frequently present in nickel hydroxide materials, are discussed including hydration, stacking fault disorder, mechanical stresses and the incorporation of ionic impurities. Several related materials are discussed, including intercalated α-derivatives and basic nickel salts. Next, a number of methods to prepare, or synthesize, nickel hydroxides are summarized, including chemical precipitation, electrochemical precipitation, sol–gel synthesis, chemical ageing, hydrothermal and solvothermal synthesis, electrochemical oxidation, microwave-assisted synthesis, and sonochemical methods. Finally, the known physical properties of the nickel hydroxides are reviewed, including their magnetic, vibrational, optical, electrical and mechanical properties. The last section in this paper is intended to serve as a summary of both the potentially useful properties of these materials and the methods for the identification and characterization of ‘unknown’ nickel hydroxide-based samples. PMID:25663812

Method of preparing electrolyte for use in fuel cells

DOEpatents

Kinoshita, Kimio; Ackerman, John P.

1978-01-01

An electrolyte compact for fuel cells includes a particulate support material of lithium aluminate that contains a mixture of alkali metal compounds, such as carbonates or hydroxides, as the active electrolyte material. The porous lithium aluminate support structure is formed by mixing alumina particles with a solution of lithium hydroxide and another alkali metal hydroxide, evaporating the solvent from the solution and heating to a temperature sufficient to react the lithium hydroxide with alumina to form lithium aluminate. Carbonates are formed by reacting the alkali metal hydroxides with carbon dioxide gas in an exothermic reaction which may proceed simultaneously with the formation with the lithium aluminate. The mixture of lithium aluminate and alkali metal in an electrolyte active material is pressed or otherwise processed to form the electrolyte structure for assembly into a fuel cell.

Structure of bayerite-based lithium-aluminum layered double hydroxides (LDHs): observation of monoclinic symmetry.

PubMed

Britto, Sylvia; Kamath, P Vishnu

2009-12-21

The double hydroxides of Li with Al, obtained by the imbibition of Li salts into bayerite and gibbsite-Al(OH)(3), are not different polytypes of the same symmetry but actually crystallize in two different symmetries. The bayerite-derived double hydroxides crystallize with monoclinic symmetry, while the gibbsite-derived hydroxides crystallize with hexagonal symmetry. Successive metal hydroxide layers in the bayerite-derived LDHs are translated by the vector ( approximately -1/3, 0, 1) with respect to each other. The exigency of hydrogen bonding drives the intercalated Cl(-) ion to a site with 2-fold coordination, whereas the intercalated water occupies a site with 6-fold coordination having a pseudotrigonal prismatic symmetry. The nonideal nature of the interlayer sites has implications for the observed selectivity of Li-Al LDHs toward anions of different symmetries.

Alkaline solution absorption of carbon dioxide method and apparatus

DOEpatents

Hobbs, D.T.

1991-01-01

Disclosed is a method for measuring the concentration of hydroxides (or pH) in alkaline solutions, using the tendency of hydroxides to adsorb CO{sub 2}. The method comprises passing CO{sub 2} over the surface of an alkaline solution in a remote tank before and after measurements of the CO{sub 2} concentration. Comparison of the measurements yields the adsorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to adsorption fraction. A schematic is given of a process system according to a preferred embodiment of the invention. 2 figs.

Protein loss in human hair from combination straightening and coloring treatments.

PubMed

França-Stefoni, Simone Aparecida; Dario, Michelli Ferrera; Sá-Dias, Tânia Cristina; Bedin, Valcinir; de Almeida, Adriano José; Baby, André Rolim; Velasco, Maria Valéria R

2015-09-01

Hair chemical treatments, such as dyeing and straightening products, are known to cause damage that can be assessed by protein loss. The aim of this study was to evaluate the hair protein loss caused by combined chemical treatments (dye and relaxer) using the validated bicinchoninic acid (BCA) method. Three kinds of straighteners, based on ammonium thioglycolate, guanidine hydroxide and sodium hydroxide, were evaluated and the least harmful combination indicated. Caucasian virgin dark brown hair tresses were treated with developed natural brown color oxidative hair dyeing and/or straightening commercial products based on ammonium thioglycolate, sodium hydroxide, or guanidine hydroxide. Protein loss quantification was assessed by the validated BCA method which has several advantages for quantifying protein loss in chemically treated hair. When both treatments (straightening and dyeing) were combined, a higher negative effect was observed, particularly for dyed hair treated with sodium hydroxide. In this case, a 356% increase in protein loss relative to virgin hair was observed and 208% in relation to only dyed hair. The combination of dying and relaxers based on ammonium thioglycolate or guanidine hydroxide caused a small increase in protein loss, suggesting that these straightening products could be the best alternatives for individuals wishing to combine both treatments. These results indicated that when application of both types of products is desired, ammonium thioglycolate or guanidine hydroxide should be chosen for the straightening process. © 2015 Wiley Periodicals, Inc.

Respiration of metal (hydr)oxides by Shewanella and Geobacter: a key role for multihaem c-type cytochromes

PubMed Central

Shi, Liang; Squier, Thomas C; Zachara, John M; Fredrickson, James K

2007-01-01

Dissimilatory reduction of metal (e.g. Fe, Mn) (hydr)oxides represents a challenge for microorganisms, as their cell envelopes are impermeable to metal (hydr)oxides that are poorly soluble in water. To overcome this physical barrier, the Gram-negative bacteria Shewanella oneidensis MR-1 and Geobacter sulfurreducens have developed electron transfer (ET) strategies that require multihaem c-type cytochromes (c-Cyts). In S. oneidensis MR-1, multihaem c-Cyts CymA and MtrA are believed to transfer electrons from the inner membrane quinone/quinol pool through the periplasm to the outer membrane. The type II secretion system of S. oneidensis MR-1 has been implicated in the reduction of metal (hydr)oxides, most likely by translocating decahaem c-Cyts MtrC and OmcA across outer membrane to the surface of bacterial cells where they form a protein complex. The extracellular MtrC and OmcA can directly reduce solid metal (hydr)oxides. Likewise, outer membrane multihaem c-Cyts OmcE and OmcS of G. sulfurreducens are suggested to transfer electrons from outer membrane to type IV pili that are hypothesized to relay the electrons to solid metal (hydr)oxides. Thus, multihaem c-Cyts play critical roles in S. oneidensis MR-1- and G. sulfurreducens-mediated dissimilatory reduction of solid metal (hydr)oxides by facilitating ET across the bacterial cell envelope. PMID:17581116

75 FR 28608 - Calcium Hydroxide; Receipt of Application for Emergency Exemption, Solicitation of Public Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-21

... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2010-0411; FRL-8826-7] Calcium Hydroxide; Receipt of... Department of Agriculture to use the pesticide calcium hydroxide (CAS No. 1305-62-0) to treat up to 1,000...: [email protected] . SUPPLEMENTARY INFORMATION: I. General Information A. Does this Action Apply to Me...

Density-functional tight-binding investigation of the structure, stability and material properties of nickel hydroxide nanotubes

NASA Astrophysics Data System (ADS)

Jahangiri, Soran; Mosey, Nicholas J.

2018-01-01

Nickel hydroxide is a material composed of two-dimensional layers that can be rolled up to form cylindrical nanotubes belonging to a class of inorganic metal hydroxide nanotubes that are candidates for applications in catalysis, energy storage, and microelectronics. The stabilities and other properties of this class of inorganic nanotubes have not yet been investigated in detail. The present study uses self-consistent-charge density-functional tight-binding calculations to examine the stabilities, mechanical properties, and electronic properties of nickel hydroxide nanotubes along with the energetics associated with the adsorption of water by these systems. The tight-binding model was parametrized for this system based on the results of first-principles calculations. The stabilities of the nanotubes were examined by calculating strain energies and performing molecular dynamics simulations. The results indicate that single-walled nickel hydroxide nanotubes are stable at room temperature, which is consistent with experimental investigations. The nanotubes possess size-dependent mechanical properties that are similar in magnitude to those of other inorganic nanotubes. The electronic properties of the nanotubes were also found to be size-dependent and small nickel oxyhydroxide nanotubes are predicted to be semiconductors. Despite this size-dependence, both the mechanical and electronic properties were found to be almost independent of the helical structure of the nanotubes. The calculations also show that water molecules have higher adsorption energies when binding to the interior of the nickel hydroxide nanotubes when compared to adsorption in nanotubes formed from other two-dimensional materials such as graphene. The increased adsorption energy is due to the hydrophilic nature of nickel hydroxide. Due to the broad applications of nickel hydroxide, the nanotubes investigated here are also expected to be used in catalysis, electronics, and clean energy production.

A Comparative Study of Ion Diffusion from Calcium Hydroxide with Various Herbal Pastes through Dentin

PubMed Central

Dhirawani, Rajesh B; Marya, Jayant; Dhirawani, Vrinda; Kumar, Vijayendra

2017-01-01

Aim The aim of this study was to evaluate the diffusion ability of ions through dentinal tubules of different nonalcoholic calcium hydroxide-containing herbal pastes and compare it with the calcium hydroxide paste prepared with saline. Materials and methods A total of 36 single-rooted premolar teeth were used in this study. The tooth crowns were removed and the root canals were prepared. Depending on the vehicle to be used for preparing calcium hydroxide pastes, six groups were made: Group I: Ca(OH)2 saline paste (control group), group II: Ca(OH)2 papaya latex paste, group III: Ca(OH)2 coconut water paste, group IV: Ca(OH)2 Ashwagandha (Withania somnifera) paste, group V: Ca(OH)2 Tulsi (Ocimum tenuiflorum) paste, and group VI: Ca(OH)2 garlic (Allium sativum) paste. After biomechanical preparation, calcium hydroxide herbal paste dressings were applied and sealed with resin-based cement. The teeth were placed in containers with deionized water, and the pH of the water was measured at regular intervals over 3, 24, 72, and 168 hours. Results We observed that all herbal pastes allowed the diffusion of ions, but pastes prepared with Ashwagandha and papaya latex showed more ion diffusion after 168 hours and marked increase in pH, depicting better support for calcium hydroxide action. Conclusion We conclude that Ashwagandha and papaya latex allow better diffusion of calcium hydroxide through den-tinal tubules, thus enhancing its action, and advise its use as a vehicle for placing intracanal medicament. How to cite this article Dausage P, Dhirawani RB, Marya J, Dhirawani V, Kumar V. A Comparative Study of Ion Diffusion from Calcium Hydroxide with Various Herbal Pastes through Dentin. Int J Clin Pediatr Dent 2017;10(1):41-44. PMID:28377654

Hydroxide diffuses slower than hydronium in water because its solvated structure inhibits correlated proton transfer

NASA Astrophysics Data System (ADS)

Chen, Mohan; Zheng, Lixin; Santra, Biswajit; Ko, Hsin-Yu; DiStasio, Robert A., Jr.; Klein, Michael L.; Car, Roberto; Wu, Xifan

2018-03-01

Proton transfer via hydronium and hydroxide ions in water is ubiquitous. It underlies acid-base chemistry, certain enzyme reactions, and even infection by the flu. Despite two centuries of investigation, the mechanism underlying why hydroxide diffuses slower than hydronium in water is still not well understood. Herein, we employ state-of-the-art density-functional-theory-based molecular dynamics—with corrections for non-local van der Waals interactions, and self-interaction in the electronic ground state—to model water and hydrated water ions. At this level of theory, we show that structural diffusion of hydronium preserves the previously recognized concerted behaviour. However, by contrast, proton transfer via hydroxide is less temporally correlated, due to a stabilized hypercoordination solvation structure that discourages proton transfer. Specifically, the latter exhibits non-planar geometry, which agrees with neutron-scattering results. Asymmetry in the temporal correlation of proton transfer leads to hydroxide diffusing slower than hydronium.

Sodium to sodium carbonate conversion process

DOEpatents

Herrmann, Steven D.

1997-01-01

A method of converting radioactive alkali metal into a low level disposable solid waste material. The radioactive alkali metal is atomized and introduced into an aqueous caustic solution having caustic present in the range of from about 20 wt % to about 70 wt % to convert the radioactive alkali metal to a radioactive alkali metal hydroxide. The aqueous caustic containing radioactive alkali metal hydroxide and CO.sub.2 are introduced into a thin film evaporator with the CO.sub.2 present in an amount greater than required to convert the alkali metal hydroxide to a radioactive alkali metal carbonate, and thereafter the radioactive alkali metal carbonate is separated from the thin film evaporator as a dry powder. Hydroxide solutions containing toxic metal hydroxide including one or more metal ions of Sb, As, Ba, Be, Cd, Cr, Pb, Hg, Ni, Se, Ag and T1 can be converted into a low level non-hazardous waste using the thin film evaporator of the invention.

Reactive transport modeling at uranium in situ recovery sites: uncertainties in uranium sorption on iron hydroxides

USGS Publications Warehouse

Johnson, Raymond H.; Tutu, Hlanganani; Brown, Adrian; Figueroa, Linda; Wolkersdorfer, Christian

2013-01-01

Geochemical changes that can occur down gradient from uranium in situ recovery (ISR) sites are important for various stakeholders to understand when evaluating potential effects on surrounding groundwater quality. If down gradient solid-phase material consists of sandstone with iron hydroxide coatings (no pyrite or organic carbon), sorption of uranium on iron hydroxides can control uranium mobility. Using one-dimensional reactive transport models with PHREEQC, two different geochemical databases, and various geochemical parameters, the uncertainties in uranium sorption on iron hydroxides are evaluated, because these oxidized zones create a greater risk for future uranium transport than fully reduced zones where uranium generally precipitates.

Aspects of Solvent Chemistry for Calcium Hydroxide Medicaments

PubMed Central

Athanassiadis, Basil

2017-01-01

Calcium hydroxide pastes have been used in endodontics since 1947. Most current calcium hydroxide endodontic pastes use water as the vehicle, which limits the dissolution of calcium hydroxide that can be achieved and, thereby, the maximum pH that can be achieved within the root canal system. Using polyethylene glycol as a solvent, rather than water, can achieve an increase in hydroxyl ions release compared to water or saline. By adopting non-aqueous solvents such as the polyethylene glycols (PEG), greater dissolution and faster hydroxyl ion release can be achieved, leading to enhanced antimicrobial actions, and other improvements in performance and biocompatibility. PMID:29065542

Color stable phosphors for LED lamps and methods for preparing them

DOEpatents

Murphy, James Edward; Setlur, Anant Achyut; Camardello, Samuel Joseph

2013-11-26

An LED lamp includes a light source configured to emit radiation with a peak intensity at a wavelength between about 250 nm and about 550 nm; and a phosphor composition configured to be radiationally coupled to the light source. The phosphor composition includes particles of a phosphor of formula I, said particles having a coating composition disposed on surfaces thereof; ((Sr.sub.1-zM.sub.z).sub.1-(x+w)A.sub.wCe.sub.x).sub.3(Al.sub.1-ySi.sub.y-)O.sub.4+y+3(x-w)F.sub.1-y-3(x-w) I wherein the coating composition comprises a material selected from aluminum oxide, magnesium oxide, calcium oxide, barium oxide, strontium oxide, zinc oxide, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide, strontium hydroxide, zinc hydroxide, aluminum phosphate, magnesium phosphate, calcium phosphate, barium phosphate, strontium phosphate, and combinations thereof; and A is Li, NA, K, or Rb, or a combination thereof; M is Ca, Ba, Mg, Zn, or a combination thereof; and 0

[Antimicrobial effect of various calcium hydroxide on Porphyromonas endodontalis in vitro].

PubMed

Du, Ting-ting; Qiu, Li-hong; Jia, Ge; Yang, Di; Guo, Yan

2012-04-01

To compare the antimicrobial activity of Endocal, calcium hydroxide paste, Calxyl, Vitapex on Porphyromonas endodontalis(P.e). (1) The antimicrobial activity of different calcium hydroxide on P.e was examined at different exposure times by dynamic nephelometry. (2) 85 freshly extracted single-rooted human teeth were selected and cut at the amelocemental junction. All roots were randomly divided into five groups. The bacteria were incubated in each canal and were sampled and counted before and after enveloping five kinds of intercanal medicine seeded. Student's t test, One-way ANOVA were used with SPSS11.0 software package for statistical analysis. The bacteria from each group were reduced significantly after intracanal medication (P<0.05). The antibacterial efficacy of Endocal and calcium hydroxide paste were superior to others under dynamic nephelometry test (P<0.05). Endocal, calcium hydroxide paste, Calxyl, Vitapex had strong inhibitory effect on P.e from infected root canals, and the rate of bacteria clearance was 95%. The antimicrobial activity of Endocal was significantly greater than others (P<0.05). Endocal, calcium hydroxide paste, Calxyl and Vitapex were effective for intercanal disinfection. The antibacterial activity of Endocal is greater than Vitapex.

Test Results for Caustic Demand Measurements on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doll, Stephanie R.; Bolling, Stacie D.

Caustic demand testing is used to determine the necessary amount of caustic required to neutralize species present in the Hanford tank waste and obtain a target molarity of free hydroxide for tank corrosion control. The presence and quantity of hydroxide-consuming analytes are just as important in determining the caustic demand as is the amount of free hydroxide present. No single data point can accurately predict whether a satisfactory hydroxide level is being met, as it is dependent on multiple factors (e.g., free hydroxide, buffers, amphoteric metal hydroxides, bicarbonate, etc.). This enclosure contains the caustic demand, scanning electron microscopy (SEM), polarizedmore » light microscopy (PLM), and X-ray diffraction (XRD) analysis for the tank 241-AX-101 (AX-101) and 241-AX-103 (AX-103) samples. The work was completed to fulfill a customer request outlined in the test plan, WRPS-1505529, “Test Plan and Procedure for Caustic Demand Testing on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples.” The work results will provide a baseline to support planned retrieval of AX-101 and AX-103.« less

Kinetics of de-N-acetylation of the chitin disaccharide in aqueous sodium hydroxide solution.

PubMed

Khong, Thang Trung; Aachmann, Finn L; Vårum, Kjell M

2012-05-01

Chitosan is prepared from chitin, a process which is carried out at highly alkaline conditions, and that can be performed either on chitin in solution (homogeneous deacetylation) or heterogeneously with the chitin as a solid throughout the reaction. We report here a study of the de-N-acetylation reaction of the chitin dimer (GlcNAc-GlcNAc) in solution. The reaction was followed by (1)H NMR spectroscopy in deuterated aqueous sodium hydroxide solution as a function of time, sodium-hydroxide concentration and temperature. The (1)H NMR spectrum of GlcNAc-GlcNAc in 2.77 M deuterated aqueous sodium hydroxide solution was assigned. The interpretation of the (1)H NMR spectra allowed us to determine the rates of de-N-acetylation of the reducing and non-reducing ends, showing that the reaction rate at the reducing end is twice the rate at the non-reducing end. The total deacetylation reaction rate was determined as a function of the hydroxide ion concentration, showing for the first time that this de-N-acetylation reaction is second order with respect to hydroxide ion concentration. No significant difference in the deacetylation rates in deuterated water compared to water was observed. The activation energy for the reaction (26-54 °C) was determined to 114.4 and 98.6 kJ/mol at 2.77 and 5.5 M in deuterated aqueous sodium hydroxide solution, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

Calcium Hydroxide-induced Proliferation, Migration, Osteogenic Differentiation, and Mineralization via the Mitogen-activated Protein Kinase Pathway in Human Dental Pulp Stem Cells.

PubMed

Chen, Luoping; Zheng, Lisha; Jiang, Jingyi; Gui, Jinpeng; Zhang, Lingyu; Huang, Yan; Chen, Xiaofang; Ji, Jing; Fan, Yubo

2016-09-01

Calcium hydroxide has been extensively used as the gold standard for direct pulp capping in clinical dentistry. It induces proliferation, migration, and mineralization in dental pulp stem cells (DPSCs), but the underlying mechanisms are still unclear. The aim of this study was to investigate the role of the mitogen-activated protein (MAP) kinase pathway in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Human DPSCs between passages 3 and 6 were used. DPSCs were preincubated with inhibitors of MAP kinases and cultured with calcium hydroxide. The phosphorylated MAP kinases were detected by Western blot analysis. Cell viability was analyzed via the methylthiazol tetrazolium assay. Cell migration was estimated using the wound healing assay. Alkaline phosphatase (ALP) expression was analyzed using the ALP staining assay. Mineralization was studied by alizarin red staining analysis. Calcium hydroxide significantly promoted the phosphorylation of the c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase. The inhibition of JNK and p38 signaling abolished calcium hydroxide-induced proliferation of DPSCs. The inhibition of JNK, p38, and extracellular signal-regulated kinase signaling suppressed the migration, ALP expression, and mineralization of DPSCs. Our study showed that the MAP kinase pathway was involved in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Automated solid-phase extraction of phenolic acids using layered double hydroxide-alumina-polymer disks.

PubMed

Ghani, Milad; Palomino Cabello, Carlos; Saraji, Mohammad; Manuel Estela, Jose; Cerdà, Víctor; Turnes Palomino, Gemma; Maya, Fernando

2018-01-26

The application of layered double hydroxide-Al 2 O 3 -polymer mixed-matrix disks for solid-phase extraction is reported for the first time. Al 2 O 3 is embedded in a polymer matrix followed by an in situ metal-exchange process to obtain a layered double hydroxide-Al 2 O 3 -polymer mixed-matrix disk with excellent flow-through properties. The extraction performance of the prepared disks is evaluated as a proof of concept for the automated extraction using sequential injection analysis of organic acids (p-hydroxybenzoic acid, 3,4-dihydroxybenzoic acid, gallic acid) following an anion-exchange mechanism. After the solid-phase extraction, phenolic acids were quantified by reversed-phase high-performance liquid chromatography with diode-array detection using a core-shell silica-C18 stationary phase and isocratic elution (acetonitrile/0.5% acetic acid in pure water, 5:95, v/v). High sensitivity and reproducibility were obtained with limits of detection in the range of 0.12-0.25 μg/L (sample volume, 4 mL), and relative standard deviations between 2.9 and 3.4% (10 μg/L, n = 6). Enrichment factors of 34-39 were obtained. Layered double hydroxide-Al 2 O 3 -polymer mixed-matrix disks had an average lifetime of 50 extractions. Analyte recoveries ranged from 93 to 96% for grape juice and nonalcoholic beer samples. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The effect of metal (hydr)oxide nano-enabling on intraparticle mass transport of organic contaminants in hybrid granular activated carbon.

PubMed

Garcia, Jose; Markovski, Jasmina; McKay Gifford, J; Apul, Onur; Hristovski, Kiril D

2017-05-15

The overarching goal of this study was to ascertain the changes in intraparticle mass transport rates for organic contaminants resulting from nano-enabled hybridization of commercially available granular activated carbon (GAC). Three different nano-enabled hybrid media were fabricated by in-situ synthesizing titanium dioxide nanoparticles inside the pores of GAC sorbent, characterized, and evaluated for removal of two model organic contaminants under realistic conditions to obtain the intraparticle mass transport (pore and surface diffusion) coefficients. The results validated the two hypotheses that: (H1) the pore diffusion rates of organic contaminants linearly decrease with decrease in cumulative pore volume caused by increase in metal (hydr)oxide nanoparticle content inside the pores of the hybrid GAC sorbent; and (H2) introduction of metal (hydr)oxide nanoparticles initially increases surface diffusivity, but additional loading causes its decrease as the increase in metal (hydr)oxide nanoparticles content continues to reduce the porosity of the GAC sorbent. Nano-enabled hybridization of commercially available GAC with metal (hydr)oxides has the potential to significantly increase the intraparticle mass transport limitations for organic contaminants. Introduction of metal (hydr)oxide nanoparticles inside the pores of a pristine sorbent causes the pore diffusion rates of organic contaminants to decrease as the cumulative pore volume is reduced. In contrast, the introduction of limited amounts of metal (hydr)oxide nanoparticles appears to facilitate the surface diffusion rates of these contaminants. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of mineral trioxide aggregate (MTA) versus calcium hydroxide cement (Dycal(®) ) in the formation of a dentine bridge: a randomised controlled trial.

PubMed

Leye Benoist, Fatou; Gaye Ndiaye, Fatou; Kane, Abdoul Wakhabe; Benoist, Henri Michel; Farge, Pierre

2012-02-01

To assess the effectiveness of mineral trioxide aggregate (MTA) used as an indirect pulp-capping material in human molar and premolar teeth. We conducted a clinical evaluation of 60 teeth, which underwent an indirect pulp-capping procedure with either MTA or calcium hydroxide cement (Dycal(®) ). Calcium hydroxide was compared with MTA and the thickness of the newly formed dentine was measured at regular time intervals. The follow-up was at 3 and 6 months, and dentine formation was monitored by radiological measurements on digitised images using Mesurim Pro(®) software. At 3 months, the clinical success rates of MTA and calcium hydroxide were 93% and 73%, respectively (P = 0.02). At 6 months, the success rate was 89.6% with MTA, and remained steady at 73% with calcium hydroxide (P = 0.63). The mean initial residual dentine thickness was 0.23 mm, and increased by 0.121 mm with MTA and by 0.136 mm with calcium hydroxide at 3 months. At 6 months, there was an increase of 0.235 mm with MTA and of 0.221 mm with calcium hydroxide.   A higher success rate was observed in the MTA group relative to the Dycal(®) group after 3 months, which was statistically significant. After 6 months, no statistically significant difference was found in the dentine thickness between the two groups. Additional histological investigations are needed to support these findings. © 2012 FDI World Dental Federation.

Fabrication of nickel-foam-supported layered zinc-cobalt hydroxide nanoflakes for high electrochemical performance in supercapacitors.

PubMed

Yuan, Peng; Zhang, Ning; Zhang, Dan; Liu, Tao; Chen, Limiao; Liu, Xiaohe; Ma, Renzhi; Qiu, Guanzhou

2014-10-04

Nickel foam supported Zn-Co hydroxide nanoflakes were fabricated by a facile solvothermal method. Benefited from the unique structure of Zn-Co hydroxide nanoflakes on a nickel foam substrate, the as prepared materials exhibited an excellent specific capacitance of 901 F g(-1) at 5 A g(-1) and remarkable cycling stability as electrode materials in supercapacitors.

An unsupported metal hydroxide for the design of molecular μ-oxo bridged heterobimetallic complexes.

PubMed

Falzone, A J; Nguyen, J; Weare, W W; Sommer, R D; Boyle, P D

2014-02-28

A terminal and unsupported chromium(III) hydroxide is reported. The terminal hydroxide is used to synthesize the first example of a heterobimetallic Ti-O-Cr compound containing an unsupported μ-oxo bridge. The heterobimetallic complex exhibits a new absorbance at 288 nm (4.32 eV), which is assigned to a metal-to-metal charge transfer (MMCT) transition.

40 CFR Appendix B to Subpart Nnn... - Free Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride

Code of Federal Regulations, 2013 CFR

2013-07-01

... buffer. 3.350-mL burette for 1.0 N sodium hydroxide. 3.4Magnetic stirrer and stir bars. 3.5250-mL beaker... N sodium hydroxide solution. 4.2Hydroxylamine hydrochloride solution, 100 grams per liter, pH... hydrochloric acid, and 0.1 N sodium hydroxide. 5.5Add 50 mL of the hydroxylamine hydrochloride solution...

40 CFR Appendix B to Subpart Nnn... - Free Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride

Code of Federal Regulations, 2014 CFR

2014-07-01

... buffer. 3.350-mL burette for 1.0 N sodium hydroxide. 3.4Magnetic stirrer and stir bars. 3.5250-mL beaker... N sodium hydroxide solution. 4.2Hydroxylamine hydrochloride solution, 100 grams per liter, pH... hydrochloric acid, and 0.1 N sodium hydroxide. 5.5Add 50 mL of the hydroxylamine hydrochloride solution...

[Comparative study of the antimicrobial effect of various cavity liners used in conservative dentistry].

PubMed

Pumarola Suñé, J; Espias Gómez, A; Canalda Sahli, C

1989-01-01

We have compared the microbiological activity of the following cavity liners: Life, Dycal II, Calcipulpe, Pure calcium hydroxide and Cavitec; against five different bacterial strains: Veillonella parvula, Bacteroides fragilis, Peptococcus s.p., Staphylococcus aureus, and Streptococcus beta hemolytic: The results demonstrate the higher antimicrobial activity of the manufactured cavity liners with calcium hydroxide base in comparison with the pure calcium hydroxide.

Apical closure of mature molar roots with the use of calcium hydroxide.

PubMed

Rotstein, I; Friedman, S; Katz, J

1990-11-01

Calcium hydroxide may induce apical root closure in affected mature teeth as well as in immature teeth. Once an apical hard tissue barrier is formed, a permanent root canal filling can be safely condensed. Two cases are described in which calcium hydroxide induced apical root closure in mature molar teeth where the apical constriction was lost because of chronic inflammatory process.

A facile one-pot synthesis of ruthenium hydroxide nanoparticles on magnetic silica: aqueous hydration of nitriles to amides.

PubMed

Baig, R B Nasir; Varma, Rajender S

2012-06-25

One-pot synthesis of ruthenium hydroxide nanoparticles on magnetic silica is described which involves the in situ generation of magnetic silica (Fe(3)O(4)@SiO(2)) and ruthenium hydroxide immobilization; the hydration of nitriles occurs in high yield and excellent selectivity using this catalyst which proceeds exclusively in aqueous medium under neutral conditions.

Improvement of the process for electrochemical impregnation of nickel hydroxide electrodes

NASA Technical Reports Server (NTRS)

Comtat, M.; Lafage, B.; Leonardi, J.

1986-01-01

Nickel hydroxide electrodes containing 11g/dsqm hydroxide, with capacities of 3.6 to 3.8 Ah/dsqm were prepared at 353 K by electrochemical impregnation. The reproducibility of the results is obtained by readjusting the pH before each preparation. The control of each electrode is done during two cycles of charge and discharge following the manufacture by a potential relaxation method.

Electrodeposition of Zn-doped α-nickel hydroxide with flower-like nanostructure for supercapacitors

NASA Astrophysics Data System (ADS)

You, Zheng; Shen, Kui; Wu, Zhicheng; Wang, Xiaofeng; Kong, Xianghua

2012-08-01

Zn-doped α-nickel hydroxide materials with flower-like nanostructures are synthesized by electrochemical deposition method. The samples are characterized by X-ray diffraction (XRD), field emission scanning electron microscope (SEM) and electrochemical measurements. XRD spectra indicate nickel hydroxide doped with Zn is α-Ni(OH)2 with excellent crystallization. The SEM observation shows that the formation of Zn-doped Ni(OH)2 includes two steps: a honeycomb-like film forms on the substrate first, then flower-like particles forms on the films. The nickel hydroxide doped with 5% Zn can maintain a maximum specific capacitance of 860 F g-1, suggesting its potential application in electrochemical capacitors.

PROCESS FOR SEPARATING PLUTONIUM BY REPEATED PRECIPITATION WITH AMPHOTERIC HYDROXIDE CARRIERS

DOEpatents

Faris, B.F.

1960-04-01

A multiple carrier precipitation method is described for separating and recovering plutonium from an aqueous solution. The hydroxide of an amphoteric metal is precipitated in an aqueous plutonium-containing solution. This precipitate, which carries plutonium, is then separated from the supernatant liquid and dissolved in an aqueous hydroxide solution, forming a second plutonium- containing solution. lons of an amphoteric metal which forms an insoluble hydroxide under the conditions existing in this second solution are added to the second solution. The precipitate which forms and which carries plutonium is separated from the supernatant liquid. Amphoteric metals which may be employed are aluminum, bibmuth, copper, cobalt, iron, lanthanum, nickel, and zirconium.

PROCESS FOR RECOVERY OF URANIUM VALUES FROM IMPURE SOLUTIONS THEREOF

DOEpatents

Kilner, S.B.

1959-11-01

A process is presented for the recovery of uraninm values from impure solutions which are obtained, for example, by washing residual uranium salt or uranium metal deposits from stainless steel surfaces using an aqueous or certain acidic aqueous solutions. The solutions include uranyl and oxidized iron, chromium, nickel, and copper ions and may contain manganese, zinc, and silver ions. In accordance with one procedure. the uranyl ions are reduced to the uranous state, and the impurity ions are complexed with cyanide under acidic conditions. The solution is then treated with ammonium hydroxide or alkali metal hydroxide to precipitate uranous hydroxide away from the complexed impurity ions in the solution. Alternatively, an excess of alkali metal cyanide is added to the reduced solution until the solution becomes sufficiently alkaline for the uranons hydroxide to precipitate. An essential feature in operating the process is in maintaining the pH of the solution sufficiently acid during the complexing operation to prevent the precipitation of the impurity metal hydroxides.

Influence of calcium hydroxide debris on the quality of endodontic apical seal.

PubMed

Contardo, L; De Luca, M; Bevilacqua, L; Breschi, L; Di Lenarda, R

2007-10-01

The aim of the study was to study investigate the influence of calcium hydroxide used as intermediate medication on the quality of apical seal of a silicon based and an experimental resin based endodontic sealer. Eighty endodontic canals were prepared and divided in four groups. Calcium hydroxide was applied in groups 2 and 4. After 7 days, medication was removed and canals were filled with gutta-percha and RoekoSeal Automix (groups 1 and 2) or Scotchbond MP+C&B cement B (groups 3 and 4). Specimens were placed into India ink, cleared and analyzed under a stereomicroscope to investigate apical leakage. Specimens that received calcium hydroxide medication showed leakage means higher than the corresponding untreated ones (i.e. group 1< group 2 and group 3< group 4; P<0.001). Calcium hydroxide interferes with the sealing ability of silicon based sealer, since it frequently remains entrapped within the endodontic space even after careful removal procedures.

Sodium to sodium carbonate conversion process

DOEpatents

Herrmann, S.D.

1997-10-14

A method is described for converting radioactive alkali metal into a low level disposable solid waste material. The radioactive alkali metal is atomized and introduced into an aqueous caustic solution having caustic present in the range of from about 20 wt % to about 70 wt % to convert the radioactive alkali metal to a radioactive alkali metal hydroxide. The aqueous caustic containing radioactive alkali metal hydroxide and CO{sub 2} are introduced into a thin film evaporator with the CO{sub 2} present in an amount greater than required to convert the alkali metal hydroxide to a radioactive alkali metal carbonate, and thereafter the radioactive alkali metal carbonate is separated from the thin film evaporator as a dry powder. Hydroxide solutions containing toxic metal hydroxide including one or more metal ions of Sb, As, Ba, Be, Cd, Cr, Pb, Hg, Ni, Se, Ag and Tl can be converted into a low level non-hazardous waste using the thin film evaporator of the invention. 3 figs.

Safety Assessment of Alumina and Aluminum Hydroxide as Used in Cosmetics.

PubMed

Becker, Lillian C; Boyer, Ivan; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

2016-11-01

This is a safety assessment of alumina and aluminum hydroxide as used in cosmetics. Alumina functions as an abrasive, absorbent, anticaking agent, bulking agent, and opacifying agent. Aluminum hydroxide functions as a buffering agent, corrosion inhibitor, and pH adjuster. The Food and Drug Administration (FDA) evaluated the safe use of alumina in several medical devices and aluminum hydroxide in over-the-counter drugs, which included a review of human and animal safety data. The Cosmetic Ingredient Review (CIR) Expert Panel considered the FDA evaluations as part of the basis for determining the safety of these ingredients as used in cosmetics. Alumina used in cosmetics is essentially the same as that used in medical devices. This safety assessment does not include metallic or elemental aluminum as a cosmetic ingredient. The CIR Expert Panel concluded that alumina and aluminum hydroxide are safe in the present practices of use and concentration described in this safety assessment. © The Author(s) 2016.

ELECTROLYTIC REDUCTION OF NITRIC ACID SOLUTIONS

DOEpatents

Alter, H.W.; Barney, D.L.

1958-09-30

A process is presented for the treatment of radioactivc waste nitric acid solutions. The nitric acid solution is neutralized with an alkali metal hydroxide in an amount sufficient to precipitate insoluble hydroxides, and after separation of the precipitate the solution is electrolyzed to convert the alkali nitrate formed, to alkali hydroxide, gaseous ammonla and oxygen. The solution is then reusable after reducing the volume by evaporating the water and dissolved ammonia.

Permanence and diffusion of borax-copper hydroxide remedial preservative applied to unseasoned pine posts : 10 year update

Treesearch

Douglas Crawford; Stan Lebow; Mike West; Bill Abbott

2005-01-01

In 1993, unseasoned pine posts were treated with groundline remedial treatment containing 3.1% copper hydroxide and 40% sodium tetraborate decahydrate (borax). The soundness of the posts was periodically evaluated using a push test. After 3.5, 6.5, and 10 years, sections were taken from two posts to determine retention of borax and copper hydroxide below ground to 36...

Process for the production of hydrogen from water

DOEpatents

Miller, William E [Naperville, IL; Maroni, Victor A [Naperville, IL; Willit, James L [Batavia, IL

2010-05-25

A method and device for the production of hydrogen from water and electricity using an active metal alloy. The active metal alloy reacts with water producing hydrogen and a metal hydroxide. The metal hydroxide is consumed, restoring the active metal alloy, by applying a voltage between the active metal alloy and the metal hydroxide. As the process is sustainable, only water and electricity is required to sustain the reaction generating hydrogen.

Process for the synthesis of iron powder

DOEpatents

Not Available

1982-03-06

A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder.

Process for the synthesis of iron powder

DOEpatents

Welbon, William W.

1983-01-01

A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder.

Emergency and Continuous Exposure Limits for Selected Airborne Contaminants. Volume 2

DTIC Science & Technology

1984-10-01

21, fluorocarbon 113, fluorocarbon 114, isopropyl alcohol, phosgene, sodium hydroxide, sulfur dioxide, vinylidene chloride . xylene. b. Identlflers/Open...fluorocarbon 114, isopropyl alcohol, phosgene, sodium hydroxide, sulfur dioxide, vinylidene chloride , xylene. c. COSATI Field/Group 1I. Availability Statement...Hydroxide 87 Sulfur Dioxide 95 Vinylidene Chloride 103 Xylene 113 -" , 0°. •. .. : V.•. ., , • .’’-.’ .’.’ INTRODUCTION The National Research Council’s

Microwave-assisted synthesis of metal oxide/hydroxide composite electrodes for high power supercapacitors - A review

NASA Astrophysics Data System (ADS)

Faraji, Soheila; Ani, Farid Nasir

2014-10-01

Electrochemical capacitors (ECs), also known as pseudocapacitors or supercapacitors (SCs), is receiving great attention for its potential applications in electric and hybrid electric vehicles because of their ability to store energy, alongside with the advantage of delivering the stored energy much more rapidly than batteries, namely power density. To become primary devices for power supply, supercapacitors must be developed further to improve their ability to deliver high energy and power simultaneously. In this concern, a lot of effort is devoted to the investigation of pseudocapacitive transition-metal-based oxides/hydroxides such as ruthenium oxide, manganese oxide, cobalt oxide, nickel oxide, cobalt hydroxide, nickel hydroxide, and mixed metal oxides/hydroxides such as nickel cobaltite and nickel-cobalt oxy-hydroxides. This is mainly due to the fact that they can produce much higher specific capacitances than typical carbon-based electric double-layer capacitors and electronically conducting polymers. This review presents supercapacitor performance data of metal oxide thin film electrodes by microwave-assisted as an inexpensive, quick and versatile technique. Supercapacitors have established the specific capacitance (Cs) principles, therefore, it is likely that metal oxide films will continue to play a major role in supercapacitor technology and are expected to considerably increase the capabilities of these devices in near future.

Magnetically retrievable nickel hydroxide functionalised AFe2O4 (A = Mn, Ni) spinel nanocatalyst for alcohol oxidation

NASA Astrophysics Data System (ADS)

Bhat, Pooja B.; Bhat, Badekai Ramachandra

2016-03-01

Ultrasmall nickel hydroxide functionalised AFe2O4 (A = Mn, Ni) nanocatalyst was synthesized by traditional co-precipitation method and was examined for oxidation of aromatic alcohols to carbonyls using hydrogen peroxide as terminal oxidant. A very high surface area of 104.55 m2 g-1 was achieved for ferromagnetic MnFe2O4 and 100.50 m2 g-1 for superparamagnetic NiFe2O4, respectively. Efficient oxidation was observed due to the synergized effect of nickel hydroxide (bronsted base) on Lewis center (Fe) of the nanocatalyst. Catalyst recycling experiments revealed that the ultrasmall nanocatalyst can be easily recovered by external magnet and applied for nearly complete oxidation of alcohols for at least five successive cycles. Furthermore, the nickel hydroxide functionalised ultrasmall nanocatalyst exhibited higher efficiency for benzyl alcohol oxidation compared to Ni(OH)2, bare MnFe2O4 and NiFe2O4. Higher conversion rate was observed for nickel hydroxide functionalised NiFe2O4 compared to MnFe2O4. Ultrasmall magnetic nickel hydroxide functionalised nanocatalyst showed environmental friendly, greener route for the oxidation of alcohols without significant loss in activity and selectivity within successive runs.

Ionic Strength-Controlled Mn (Hydr)oxide Nanoparticle Nucleation on Quartz: Effect of Aqueous Mn(OH)2.

PubMed

Jung, Haesung; Jun, Young-Shin

2016-01-05

The early formation of manganese (hydr)oxide nanoparticles at mineral-water interfaces is crucial in understanding how Mn oxides control the fate and transport of heavy metals and the cycling of nutrients. Using atomic force microscopy, we investigated the heterogeneous nucleation and growth of Mn (hydr)oxide under varied ionic strengths (IS; 1-100 mM NaNO3). Experimental conditions (i.e., 0.1 mM Mn(2+) (aq) concentration and pH 10.1) were chosen to be relevant to Mn remediation sites. We found that IS controls Mn(OH)2 (aq) formation, and that the controlled Mn(OH)2 (aq) formation can affect the system's saturation and subsequent Mn(OH)2 (s) and further Mn3O4 (s) nanoparticle formation. In 100 mM IS system, nucleated Mn (hydr)oxide particles had more coverage on the quartz substrate than those in 1 mM and 10 mM IS systems. This high IS also resulted in low supersaturation ratio and thus favor heterogeneous nucleation, having better structural matching between nucleating Mn (hydr)oxides and quartz. The unique information obtained in this work improves our understanding of Mn (hydr)oxide formation in natural as well as engineered aqueous environments, such as groundwater contaminated by natural leachate and acid mine drainage remediation.

Influence of calcium hydroxide on the post-treatment pain in Endodontics: A systematic review

PubMed Central

Anjaneyulu, K.; Nivedhitha, Malli Sureshbabu

2014-01-01

Introduction: Pain of endodontic origin has been a major concern to the patients and the clinicians for many years. Post-operative pain is associated with inflammation in the periradicular tissues caused by irritants egressing from root canal during treatment. It has been suggested that calcium hydroxide intra-canal medicament has pain-preventive properties because of its anti-microbial or tissue altering effects. Some dispute this and reasoned that calcium hydroxide may initiate or increase pain by inducing or increasing inflammation. Objective: To evaluate the effectiveness of calcium hydroxide in reducing the post-treatment pain when used as an intra-canal medicament Materials and Methods: The following databases were searched: PubMed CENTRAL (until July 2013), MEDLINE, and Cochrane Database of Systematic Reviews. Bibliographies of clinical studies and reviews identified in the electronic search were analyzed for studies published outside the electronically searched journals. The primary outcome measure was to evaluate the post-treatment pain reduction when calcium hydroxide is used as an intra-canal medicament in patients undergoing root canal therapy. Results: The reviews found some clinical evidence that calcium hydroxide is not very effective in reducing post-treatment pain when it is used alone, but its effectiveness can be increased when used in combination with other medicaments like chlorhexidine and camphorated monochlorophenol (CMCP). Conclusion: Even though calcium hydroxide is one of the most widely used intra-canal medicament due to its anti-microbial properties, there is no clear evidence of its effect on the post-treatment pain after the chemo-mechanical root canal preparation. PMID:24944439

A prospective, open, comparative study of 5% potassium hydroxide solution versus cryotherapy in the treatment of genital warts in men*

PubMed Central

Camargo, Caio Lamunier de Abreu; Belda, Walter; Fagundes, Luiz Jorge; Romiti, Ricardo

2014-01-01

BACKGROUND Genital warts are caused by human papillomavirus infection and represent one of the most common sexually transmitted diseases. Many infections are transient but the virus may recur, persist, or become latent. To date, there is no effective antiviral treatment to eliminate HPV infection and most therapies are aimed at the destruction of visible lesions. Potassium hydroxide is a strong alkali that has been shown to be safe and effective for the treatment of genital warts and molluscum contagiosum. Cryotherapy is considered one of the most established treatments for genital warts. No comparative trials have been reported to date on the use of potassium hydroxide for genital warts. OBJECTIVE A prospective, open-label, randomized clinical trial was conducted to compare topical potassium hydroxide versus cryotherapy in the treatment of genital warts affecting immunocompetent, sexually active men. METHODS Over a period of 10 months, 48 patients were enrolled. They were randomly divided into two groups and selected on an alternative basis for either potassium hydroxide therapy or cryotherapy. While response to therapy did not differ substantially between both treatment modalities, side effects such as local pain and post-treatment hypopigmentation were considerably more prevalent in the groups treated using cryotherapy. RESULT In our study, potassium hydroxide therapy proved to be at least as effective as cryotherapy and offered the benefit of a better safety profile. CONCLUSION Topical 5% potassium hydroxide presents an effective, safe, and low-cost treatment modality for genital warts in men and should be included in the spectrum of therapies for genital warts. PMID:24770498

Coupling fractionation and batch desorption to understand arsenic and fluoride co-contamination in the aquifer system.

PubMed

Kumar, Manish; Das, Nilotpal; Goswami, Ritusmita; Sarma, Kali Prasad; Bhattacharya, Prosun; Ramanathan, A L

2016-12-01

The present work is an attempt to study As and F+ coevality using laboratory based assays which couples fractionation and batch dissolution experiments. Sequential extraction procedure (SEP) resulting into five "operationally defined phases", was performed on sediment and soil samples collected from the Brahmaputra flood plains, Assam, India. High correlation between the Fe (hydr)oxide fraction and total As content of the soil/sediment sample indicates the involvement of Fe (hydr)oxides as the principal source of As. F - being an anion has high potential to be sorbed onto positively charged surfaces. Findings of the SEP were used to design the batch desorption experiments by controlling the Fe (hydr)oxide content of the soil/sediment. Desorption of As and F - was observed under acidic, neutral and alkaline pH from untreated and Fe (hydr)oxide removed samples. Highest amount of As and F - were found to be released from untreated samples under alkaline pH, while the amount leached from samples with no Fe (hydr)oxide was low. The study showed that the Fe (hydr)oxide fraction commonly found in the soils and sediments, had high affinity for negatively charged species like F - oxyanions of As, AsO 4 3- (arsenate) and AsO 3 3- (arsenite). Fe (hydr)oxide fraction was found to play the major role in co-evolution of As and F - . Two sorption coefficients were proposed based on easily leachable fraction and As present in the groundwater of sampling location for understanding of contamination vulnerability from the leaching. Copyright © 2016 Elsevier Ltd. All rights reserved.

A prospective, open, comparative study of 5% potassium hydroxide solution versus cryotherapy in the treatment of genital warts in men.

PubMed

Camargo, Caio Lamunier de Abreu; Belda Junior, Walter; Fagundes, Luiz Jorge; Romiti, Ricardo

2014-01-01

Genital warts are caused by human papillomavirus infection and represent one of the most common sexually transmitted diseases. Many infections are transient but the virus may recur, persist, or become latent. To date, there is no effective antiviral treatment to eliminate HPV infection and most therapies are aimed at the destruction of visible lesions. Potassium hydroxide is a strong alkali that has been shown to be safe and effective for the treatment of genital warts and molluscum contagiosum. Cryotherapy is considered one of the most established treatments for genital warts. No comparative trials have been reported to date on the use of potassium hydroxide for genital warts. A prospective, open-label, randomized clinical trial was conducted to compare topical potassium hydroxide versus cryotherapy in the treatment of genital warts affecting immunocompetent, sexually active men. Over a period of 10 months, 48 patients were enrolled. They were randomly divided into two groups and selected on an alternative basis for either potassium hydroxide therapy or cryotherapy. While response to therapy did not differ substantially between both treatment modalities, side effects such as local pain and post-treatment hypopigmentation were considerably more prevalent in the groups treated using cryotherapy. In our study, potassium hydroxide therapy proved to be at least as effective as cryotherapy and offered the benefit of a better safety profile. Topical 5% potassium hydroxide presents an effective, safe, and low-cost treatment modality for genital warts in men and should be included in the spectrum of therapies for genital warts.

Dry cell battery poisoning

MedlinePlus

Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

Calcium hydroxide poisoning

MedlinePlus

These products contain calcium hydroxide: Cement Limewater Many industrial solvents and cleaners (hundreds to thousands of construction products, flooring strippers, brick cleaners, cement thickening products, and many ...

Negative cerium anomalies in manganese (hydr)oxide precipitates due to cerium oxidation in the presence of dissolved siderophores

NASA Astrophysics Data System (ADS)

Kraemer, Dennis; Tepe, Nathalie; Pourret, Olivier; Bau, Michael

2017-01-01

We present experimental results on the sorption behavior of rare earth elements and yttrium (REY) on precipitating manganese (hydr)oxide in the presence of the biogenic siderophore desferrioxamine B (DFOB). In marked contrast to inorganic systems, where preferential adsorption of HREY and depletion of LREY is commonly observed in manganese (hydr)oxide precipitates, sorption of REY in presence of the DFOB siderophore leads to HREY-depleted and LREY-enriched patterns in the precipitates. Moreover, our data indicate that surface oxidation of Ce(III) to Ce(IV) during sorption onto manganese (hydr)oxides and the resulting development of a positive Ce anomaly, which are commonly observed in inorganic experiments, are prevented in the presence of DFOB. Instead, Ce(III) is oxidized to Ce(IV) but associated with the dissolved desferrioxamine B which forms complexes with Ce(IV), that are at least twenty orders of magnitude more stable than those with Ce(III) and REY(III). The overall result is the formation of a positive Ce anomaly in the solution and a negative Ce anomaly in the Mn (hydr)oxides. The distribution of the strictly trivalent REY and Eu(III) between the manganese (hydr)oxide phase and the remaining ambient solution mimics the distribution of published stability constants for complexes of REY(III) with DFOB, i.e. the heavy REY form more stable complexes with the ligand and hence are better shielded from sorption than the LREY. Surface complexation modeling corroborates our experimental results. Negative Ce anomalies in Mn precipitates have been described from biogenic Mn oxides. Our results provide experimental evidence for the development of negative Ce anomalies in abiogenic Mn (hydr)oxide precipitates and show that the presence of the widespread siderophore desferrioxamine B during mineral precipitation results in HREY-depleted Mn (hydr)oxides with negative Ce anomalies.

40 CFR Appendix A to Subpart Ddd... - Free Formaldehyde Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method

Code of Federal Regulations, 2013 CFR

2013-07-01

... buffer. 3.350-mL burette for 1.0 N sodium hydroxide. 3.4Magnetic stirrer and stir bars. 3.5250-mL beaker... N sodium hydroxide solution. 4.2Hydroxylamine hydrochloride solution, 100 grams per liter, pH... prestandardized pH meter, 1.0 N hydrochloric acid, 0.1 N hydrochloric acid, and 0.1 N sodium hydroxide. 5.5Add 50...

40 CFR Appendix A to Subpart Ddd... - Free Formaldehyde Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method

Code of Federal Regulations, 2012 CFR

2012-07-01

... buffer. 3.350-mL burette for 1.0 N sodium hydroxide. 3.4Magnetic stirrer and stir bars. 3.5250-mL beaker... N sodium hydroxide solution. 4.2Hydroxylamine hydrochloride solution, 100 grams per liter, pH... prestandardized pH meter, 1.0 N hydrochloric acid, 0.1 N hydrochloric acid, and 0.1 N sodium hydroxide. 5.5Add 50...

40 CFR Appendix A to Subpart Ddd... - Free Formaldehyde Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method

Code of Federal Regulations, 2014 CFR

2014-07-01

... buffer. 3.350-mL burette for 1.0 N sodium hydroxide. 3.4Magnetic stirrer and stir bars. 3.5250-mL beaker... N sodium hydroxide solution. 4.2Hydroxylamine hydrochloride solution, 100 grams per liter, pH... prestandardized pH meter, 1.0 N hydrochloric acid, 0.1 N hydrochloric acid, and 0.1 N sodium hydroxide. 5.5Add 50...

Catalytic and inhibiting effects of lithium peroxide and hydroxide on sodium chlorate decomposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cannon, J.C.; Zhang, Y.

1995-09-01

Chemical oxygen generators based on sodium chlorate and lithium perchlorate are used in airplanes, submarines, diving, and mine rescue. Catalytic decomposition of sodium chlorate in the presence of cobalt oxide, lithium peroxide, and lithium hydroxide is studied using thermal gravimetric analysis. Lithium peroxide and hydroxide are both moderately active catalysts for the decomposition of sodium chlorate when used alone, and inhibitors when used with the more active catalyst cobalt oxide.

Process for the synthesis of iron powder

DOEpatents

Welbon, W.W.

1983-11-08

A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder. 2 figs.

Friction modifier using adherent metallic multilayered or mixed element layer conversion coatings

NASA Technical Reports Server (NTRS)

Schramm, Harry F. (Inventor); Defalco, Frank G. (Inventor); Starks, Sr., Lloyd L. (Inventor)

2012-01-01

A process for creating conversion coatings and spin, drawing, and extrusion finishes for surfaces, wherein the conversion coatings and spin, drawing, and extrusion finishes contain potassium, phosphorus, nitrogen, silicon, and one or more non-alkaline metals. The process comprises forming a first aqueous solution of silicate, potassium hydroxide, and ammonium hydroxide; forming a second aqueous solution of water, phosphoric acid, ammonium hydroxide, an alkali metal hydroxide, and one or more non-alkaline metals, and then combining the first solution with the second solution to form a final solution. This final solution forms an anti-friction multi-layer conversion coating or a spin, drawing, and extrusion finish on a surface when applied to the surface, either directly or as an additive in lubricating fluids.

Uptake of Au(III) Ions by Aluminum Hydroxide and Their Spontaneous Reduction to Elemental Gold (Au(0)).

PubMed

Yokoyama; Matsukado; Uchida; Motomura; Watanabe; Izawa

2001-01-01

The behavior of AuCl(4)(-) ions during the formation of aluminum hydroxide at pH 6 was examined. With an increase in NaCl concentration, the content of gold taken up by aluminum hydroxide decreased, suggesting that chloro-hydroxy complexes of Au(III) ion were taken up due to the formation of Al-O-Au bonds. It was found unexpectedly that the Au(III) ions taken up were spontaneously reduced to elemental gold without addition of a specific reducing reagent and then colloidal gold particles were formed. The mechanisms for the uptake of Au(III) ions by aluminum hydroxide and for their spontaneous reduction are discussed. Copyright 2001 Academic Press.

Carbonation of metal silicates for long-term CO2 sequestration

DOEpatents

Blencoe, James G; Palmer, Donald A; Anovitz, Lawrence M; Beard, James S

2014-03-18

In a preferred embodiment, the invention relates to a process of sequestering carbon dioxide. The process comprises the steps of: (a) reacting a metal silicate with a caustic alkali-metal hydroxide to produce a hydroxide of the metal formerly contained in the silicate; (b) reacting carbon dioxide with at least one of a caustic alkali-metal hydroxide and an alkali-metal silicate to produce at least one of an alkali-metal carbonate and an alkali-metal bicarbonate; and (c) reacting the metal hydroxide product of step (a) with at least one of the alkali-metal carbonate and the alkali-metal bicarbonate produced in step (b) to produce a carbonate of the metal formerly contained in the metal silicate of step (a).

Carbonation of metal silicates for long-term CO.sub.2 sequestration

DOEpatents

Blencoe, James G [Harriman, TN; Palmer, Donald A [Oliver Springs, TN; Anovitz, Lawrence M [Knoxville, TN; Beard, James S [Martinsville, VA

2012-02-14

In a preferred embodiment, the invention relates to a process of sequestering carbon dioxide. The process comprises the steps of: (a) reacting a metal silicate with a caustic alkali-metal hydroxide to produce a hydroxide of the metal formerly contained in the silicate; (b) reacting carbon dioxide with at least one of a caustic alkali-metal hydroxide and an alkali-metal silicate to produce at least one of an alkali-metal carbonate and an alkali-metal bicarbonate; and (c) reacting the metal hydroxide product of step (a) with at least one of the alkali-metal carbonate and the alkali-metal bicarbonate produced in step (b) to produce a carbonate of the metal formerly contained in the metal silicate of step (a).

Evaluation of hydroxyl ion diffusion in dentin and injectable forms and a simple powder-water calcium hydroxide paste: an in vitro study.

PubMed

Eftekhar, Behrooz; Moghimipour, Eskandar; Eini, Ebrahim; Jafarzadeh, Mansour; Behrooz, Narges

2014-08-01

Intra canal medicaments are used to reduce the number of bacteria and reinfection in endodontic procedures. Calcium Hydroxide was introduced to endodontics by Herman as an intracanal antimicrobial agent. The aim of this study was to present an injectable formulation of calcium hydroxide then compare the final pH of this new formulation with Metapaste and evaluate the effect of a mixture of Calcium Hydroxide powder with water on human extracted teeth. A total of 49 extracted human single-canal roots without caries and visible microcracks were included in this study. The teeth were decoronated and length of teeth was measured 1 mm anatomic apex. The canals were prepared using step-back technique. A cavity was created in the middle third of the buccal surface of all roots. The teeth were randomly divided into five groups: Group A (n = 15): In this group the root canals were filled with a mixture of calcium hydroxide powder and distilled water. Group B (n = 15): Included roots that were filled with Metapaste. Group C (n = 15): Root canals of this group were filled with new formulation of calcium hydroxide paste. Group D (negative control, n = 2): Included roots that were filled with a mixture of calcium hydroxide powder and distilled water. Group E (positive control, n = 2): Root canals of this group were filled with a mixture of calcium hydroxide powder and distilled water. Each tooth was immersed in a separate closed container with 4 mL saline for 2 weeks, pH of liquids were measured with an electrical pH meter after 7 and 14 days. The SPSS software (version 13) was used for data analysis. Analysis of variance (ANOVA) and Tukey tests were used for the statistical evaluation of results. There was no significant difference at 7th day between the groups (P = 0.17) but at 14th day, a significant difference was observed between the groups (P = 0.04). The new formulation of calcium hydroxide with methylcellulose base has slower ionic dissolution, more durability and longevity of alkaline properties in comparison to combination of powder with distilled water and is comparable with other commercial products.

Antibiofilm efficacy of silver nanoparticles as a vehicle for calcium hydroxide medicament against Enterococcus faecalis.

PubMed

Afkhami, Farzaneh; Pourhashemi, Seyyed Jalal; Sadegh, Mona; Salehi, Yasaman; Fard, Mohammad Javad Kharrazi

2015-12-01

The aim of the present study was to investigate antibacterial characteristic and Enterococcus faecalis (E. faecalis) biofilm suppression effect of different vehicles of calcium hydroxide as intracanal medicaments in short and long-term. Fifty-four human single-root teeth were contaminated with E. faecalis bacteria. The teeth were randomly divided into three experimental (n=16) and one control group (n=6). Each group was then exposed to various intracanal medicaments, namely calcium hydroxide paste (group 1), calcium hydroxide with chlorhexidine (group 2), calcium hydroxide with silver nanoparticles suspension (AgNPs) (group 3), and saline as the control group (group 4). Cultures were made from each group after one week and one month, and the number of colonies was counted. Moreover, a sample of each group was examined under electron microscope. Kruskal-Wallis test served for inter-group comparisons, and Mann-Whitney test served for comparison between the two incubation periods. All the intracanal medicaments resulted in significant decrease in number of colonies compared to control group in both incubation periods. After one week, the mixture of calcium hydroxide and AgNPs was the most effective medicament against E. faecalis bacteria (p<.05). No significant difference in antibacterial effect of the medicaments existed after one month incubation period (p>.05). AgNPs was more effective on the E. faecalis biofilm than other tested vehicles in short-term medication. AgNPs seems to have a good potential to be used as an appropriate vehicle of calcium hydroxide in order to eliminate of E. faecalis biofilm from human dentine in short-term. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effect of retreatment procedure on the pH changes at the surface of root dentin using two different calcium hydroxide pastes

PubMed Central

Kazemipoor, Maryam; Tabrizizadeh, Mehdi; Dastani, Milad; Hakimian, Roqayeh

2012-01-01

Aim: To compare pH changes at the cervical, middle and apical surfaces of root dentin in retreated and non- retreated teeth, after canal obturation with two different calcium hydroxide pastes. Materials and Methods: After instrumentation of 55 extracted teeth, three cavities with 0.75 mm depth and 1.5 mm in diameter were drilled at buccal root surface. The teeth were randomly divided into five groups. Canals in the first two groups were filled with either mixture of calcium hydroxide and saline solution and calcium hydroxide and 2% chlorhexidine (CHX). In the third and fourth groups canals were first obturated with gutta-percha and AH26 sealer, and then materials were removed. After 2 days canals were filled with two different calcium hydroxide pastes similar to the first and the second groups. The pH was measured in the prepared cavities at 1, 3, 7 and 14 days. Results: In the non-retreated groups, pH at the surface of the roots was significantly higher in comparison to the retreated ones (P value < 0.001). pH values were significantly higher in the non-retreated teeth filling with calcium hydroxide and saline solution (P value < 0.001). Conclusion: Regarding to the little pH changes at the surface of dentin in retreated teeth, the hydroxyl ions cannot penetrate into the dentinal tubules. Thus, to achieve higher pH at the root surface in retreated teeth, it is clinically advisable to remove more dentin from the inner walls and to use normal saline as a vehicle for calcium hydroxide rather than acidic pH materials. PMID:23112482

The effect of retreatment procedure on the pH changes at the surface of root dentin using two different calcium hydroxide pastes.

PubMed

Kazemipoor, Maryam; Tabrizizadeh, Mehdi; Dastani, Milad; Hakimian, Roqayeh

2012-10-01

To compare pH changes at the cervical, middle and apical surfaces of root dentin in retreated and non- retreated teeth, after canal obturation with two different calcium hydroxide pastes. After instrumentation of 55 extracted teeth, three cavities with 0.75 mm depth and 1.5 mm in diameter were drilled at buccal root surface. The teeth were randomly divided into five groups. Canals in the first two groups were filled with either mixture of calcium hydroxide and saline solution and calcium hydroxide and 2% chlorhexidine (CHX). In the third and fourth groups canals were first obturated with gutta-percha and AH26 sealer, and then materials were removed. After 2 days canals were filled with two different calcium hydroxide pastes similar to the first and the second groups. The pH was measured in the prepared cavities at 1, 3, 7 and 14 days. In the non-retreated groups, pH at the surface of the roots was significantly higher in comparison to the retreated ones (P value < 0.001). pH values were significantly higher in the non-retreated teeth filling with calcium hydroxide and saline solution (P value < 0.001). Regarding to the little pH changes at the surface of dentin in retreated teeth, the hydroxyl ions cannot penetrate into the dentinal tubules. Thus, to achieve higher pH at the root surface in retreated teeth, it is clinically advisable to remove more dentin from the inner walls and to use normal saline as a vehicle for calcium hydroxide rather than acidic pH materials.

Comparative evaluation of different forms of calcium hydroxide in apexification.

PubMed

Ghosh, Subhankar; Mazumdar, Dibyendu; Ray, Pradip Kumar; Bhattacharya, Bhaswar

2014-01-01

One out of every two children sustains a dental injury most often between 8 and 10 years of age. Majority of these teeth subsequently become non-vital and most often with immature apex. Management of these teeth is an enormous challenge for lack of apical stop. Calcium hydroxide in various formulations has maximum literature support in favor of successful apexification or induced apical closure. The aim of the following study is to determine the efficacy of calcium hydroxide in a different formulation to induce apexification. The present study was undertaken on 51 children of 8-10 years of age (both sexes) at Dr. R Ahmed Dental College and Hospital from April 2006 to March 2007. All children had one or two maxillary permanent central incisor (s), non-vital and apices open. In all the cases, apexification was attempted with either calcium hydroxide mixed with sterile distilled water, or calcium hydroxide plus iodoform in methyl cellulose base, or calcium hydroxide plus iodoform in polysilicone oil base. The success of apexification was determined on the basis of clinical and radiographic criteria. In the pre-operative asymptomatic cases (72.55%), failure occurred in only 5.45% cases and pre-operative symptomatic cases failure rate was as high as 35.71%. Success rate was 94.6% in cases with narrow open apices, whereas 64.28% in wide open apices. In cases with pre-existing apical radiolucencies, successful apexification occurred in 63.63% and success rate was 92.5% in the cases without pre-existing apical radiolucencies. Average time consumed for apexification was minimum with calcium hydroxide plus iodoform in polysilicone oil base. The overall success rate observed to be 86.27%, which is in close proximity to the findings of most of the previous studies across the globe.

PROCESS OF SEPARATING PLUTONIUM FROM URANIUM

DOEpatents

Brown, H.S.; Hill, O.F.

1958-09-01

A process is presented for recovering plutonium values from aqueous solutions. It comprises forming a uranous hydroxide precipitate in such a plutonium bearing solution, at a pH of at least 5. The plutonium values are precipitated with and carried by the uranium hydroxide. The carrier precipitate is then redissolved in acid solution and the pH is adjusted to about 2.5, causing precipitation of the uranous hydroxide but leaving the still soluble plutonium values in solution.

Staining of Tissue Sections for Electron Microscopy with Heavy Metals

PubMed Central

Watson, Michael L.

1958-01-01

Descriptions of three heavy metal stains and methods of application to tissue sections for electron microscopy are presented. Lead hydroxide stains rather selectively two types of particles in liver: those associated with the endoplasmic reticulum and containing ribonucleic acid and other somewhat larger particles. Barium hydroxide emphasizes certain bodies within vesicles of the Golgi region of hepatic cells. Alkalized lead acetate is useful as a general stain, as are also lead and barium hydroxides. PMID:13610936

Colloid labelled with radionuclide and method

DOEpatents

Atcher, R.W.; Hines, J.J.

1990-11-13

A ferric hydroxide colloid having an alpha-emitting radionuclide essentially on the outer surfaces and a method of forming same. The method includes oxidizing a ferrous hydroxide to ferric hydroxide in the presence of a preselected radionuclide to form a colloid having the radionuclide on the outer surface thereof, and thereafter washing the colloid, and suspending the washed colloid in a suitable solution. The labelled colloid is useful in cancer therapy and for the treatment of inflamed joints. No Drawings

Method of making colloid labeled with radionuclide

DOEpatents

Atcher, Robert W.; Hines, John J.

1991-01-01

A ferric hydroxide colloid having an alpha-emitting radionuclide essentially on the outer surfaces and a method of forming same. The method includes oxidizing a ferrous hydroxide to ferric hydroxide in the presence of a preselected radionuclide to form a colloid having the radionuclide on the outer surface thereof, and thereafter washing the colloid, and suspending the washed colloid in a suitable solution. The labelled colloid is useful in cancer therapy and for the treatment of inflamed joints.

Colloid labelled with radionuclide and method

DOEpatents

Atcher, Robert W.; Hines, John J.

1990-01-01

A ferric hydroxide colloid having an alpha-emitting radionuclide essentially on the outer surfaces and a method of forming same. The method includes oxidizing a ferrous hydroxide to ferric hydroxide in the presence of a preselected radionuclide to form a colloid having the radionuclide on the outer surface thereof, and thereafter washing the colloid, and suspending the washed colloid in a suitable solution. The labelled colloid is useful in cancer therapy and for the treatment of inflamed joints.

40 CFR Appendix B to Subpart Nnn... - Free Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride

Code of Federal Regulations, 2012 CFR

2012-07-01

... 4.0 with pH 4.0 buffer and pH 7 with pH 7.0 buffer. 3.350-mL burette for 1.0 N sodium hydroxide. 3.... 3.8Timer. 4. Reagents 4.1Standardized 1.0 N sodium hydroxide solution. 4.2Hydroxylamine.... Start the timer. 5.6Stir for 5 minutes. Titrate to pH 4.0 with standardized 1.0 N sodium hydroxide...

Solvent and process for recovery of hydroxide from aqueous mixtures

DOEpatents

Moyer, Bruce A.; Chambliss, C. Kevin; Bonnesen, Peter V.; Keever, Tamara J.

2001-01-01

Hydroxide values and associated alkali metal may be recovered from alkaline aqueous solutions using classes of fluorinated alcohols in a water immiscible solvent. The alcohols are characterized by fluorine substituents which are proximal to the acidic alcohol protons and are located to adjust the acidity of the extractant and the solubility of the extractant in the solvent. A method for stripping the extractant and solvent to regenerate the extractant and purified aqueous hydroxide solution is described.

Effective Construction of High-quality Iron Oxy-hydroxides and Co-doped Iron Oxy-hydroxides Nanostructures: Towards the Promising Oxygen Evolution Reaction Application

NASA Astrophysics Data System (ADS)

Zhang, Xinyu; An, Li; Yin, Jie; Xi, Pinxian; Zheng, Zhiping; Du, Yaping

2017-03-01

Rational design of high efficient and low cost electrocatalysts for oxygen evolution reaction (OER) plays an important role in water splitting. Herein, a general gelatin-assisted wet chemistry method is employed to fabricate well-defined iron oxy-hydroxides and transitional metal doped iron oxy-hydroxides nanomaterials, which show good catalytic performances for OER. Specifically, the Co-doped iron oxy-hydroxides (Co0.54Fe0.46OOH) show the excellent electrocatalytic performance for OER with an onset potential of 1.52 V, tafel slope of 47 mV/dec and outstanding stability. The ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the pure iron oxy-hydroxide (FeOOH) catalysts, originate from the branch structure of Co0.54Fe0.46OOH on its surface so as to provide many active edge sites, enhanced mass/charge transport capability, easy release oxygen gas bubbles, and strong structural stability, which are advantageous for OER. Meanwhile, Co-doping in FeOOH nanostructures constitutes a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal-air batteries, regenerative fuel cells, and other important clean energy devices. This work may provide a new insight into constructing the promising water oxidation catalysts for practical clean energy application.

Effective Construction of High-quality Iron Oxy-hydroxides and Co-doped Iron Oxy-hydroxides Nanostructures: Towards the Promising Oxygen Evolution Reaction Application.

PubMed

Zhang, Xinyu; An, Li; Yin, Jie; Xi, Pinxian; Zheng, Zhiping; Du, Yaping

2017-03-08

Rational design of high efficient and low cost electrocatalysts for oxygen evolution reaction (OER) plays an important role in water splitting. Herein, a general gelatin-assisted wet chemistry method is employed to fabricate well-defined iron oxy-hydroxides and transitional metal doped iron oxy-hydroxides nanomaterials, which show good catalytic performances for OER. Specifically, the Co-doped iron oxy-hydroxides (Co 0.54 Fe 0.46 OOH) show the excellent electrocatalytic performance for OER with an onset potential of 1.52 V, tafel slope of 47 mV/dec and outstanding stability. The ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the pure iron oxy-hydroxide (FeOOH) catalysts, originate from the branch structure of Co 0.54 Fe 0.46 OOH on its surface so as to provide many active edge sites, enhanced mass/charge transport capability, easy release oxygen gas bubbles, and strong structural stability, which are advantageous for OER. Meanwhile, Co-doping in FeOOH nanostructures constitutes a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal-air batteries, regenerative fuel cells, and other important clean energy devices. This work may provide a new insight into constructing the promising water oxidation catalysts for practical clean energy application.

The Efficacy of Calcium Hydroxide Powder mixed with 0.2% Chlorhexidine Digluconate or mixed with Normal Saline as Intracanal Medicament in the Treatment of Apical Periodontitis.

PubMed

Menakaya, Ifeoma N; Adegbulugbe, Ilemobade C; Oderinu, Olabisi H; Shaba, Olufemi P

2015-08-01

To compare the efficacy of calcium hydroxide powder mixed with 0.2% chlorhexidine digluconate or mixed with normal saline as intracanal medicament in the treatment of apical periodontitis. Subjects were 55 in number aged 17 to 60 years. Two-visit conventional root canal treatment was performed on 70 teeth. The teeth were divided by randomization (balloting) into two groups: control group and experimental group, each with 35 teeth treated with calcium hydroxide mixed with normal saline or with 0.2% chlorhexidine digluconate as intracanal medicament respectively. All treated teeth were evaluated clinically and radiographically for signs and symptom of periapical infection at specified periods postoperatively. Overall efficacy of medicament was rated based on quality guidelines for endodontic treatment by the European Society of Endodontology 2006. A postoperative favorable outcome of 97.1% in the control group and 94.3% in the experimental group was observed at 6-month review. This difference was not statistically significant (p > 0.05). The use of normal saline or 0.2% chlorhexidine digluconate to mix calcium hydroxide used as intracanal medicament during endodontic treatment resulted in high postoperative favorable outcomes. Efficacy of 0.2% chlorhexidine digluconate as a vehicle for mixing calcium hydroxide as an intracanal medicament in the treatment of apical periodontitis is comparable to the efficacy of calcium hydroxide mixed with normal saline.

Arsenic release from arsenopyrite weathering: insights from sequential extraction and microscopic studies.

PubMed

Basu, Ankan; Schreiber, Madeline E

2013-11-15

At a former As mine site, arsenopyrite oxidation has resulted in formation of scorodite and As-bearing iron hydroxide, both in host rock and mine tailings. Electron microprobe analysis documents that arsenopyrite weathers along two pathways: one that involves formation of sulfur, and one that does not. In both pathways, arsenopyrite oxidizes to form scorodite, which dissolves incongruently to form As-bearing iron hydroxides. From a mass balance perspective, arsenopyrite oxidation to scorodite conserves As, but as scorodite dissolves incongruently to iron hydroxides, As is released to solution, resulting in elevated As concentrations in the headwater stream adjacent to the site. The As-bearing iron hydroxide is the dominant solid phase reservoir of As in mine tailings and stream sediment, as suggested by sequential extraction. This As-bearing iron hydroxide is stable under the aerobic and pH 4-6 conditions at the site; however, changes in biogeochemical conditions resulting from sediment burial or future remedial efforts, which could promote As release from this reservoir due to reductive dissolution, should be avoided. Copyright © 2012 Elsevier B.V. All rights reserved.

Energy and structure of bonds in the interaction of organic anions with layered double hydroxide nanosheets: A molecular dynamics study

NASA Astrophysics Data System (ADS)

Tsukanov, A. A.; Psakhie, S. G.

2016-01-01

The application of hybrid and hierarchical nanomaterials based on layered hydroxides and oxyhydroxides of metals is a swiftly progressing field in biomedicine. Layered double hydroxides (LDH) possess a large specific surface area, significant surface electric charge and biocompatibility. Their physical and structural properties enable them to adsorb various kinds of anionic species and to transport them into cells. However, possible side effects resulting from the interaction of LDH with anions of the intercellular and intracellular medium need to be considered, since such interaction can potentially disrupt ion transport, signaling processes, apoptosis, nutrition and proliferation of living cells. In the present paper molecular dynamics is used to determine the energies of interaction of organic anions (aspartic acid, glutamic acid and bicarbonate) with a fragment of layered double hydroxide Mg/Al-LDH. The average number of hydrogen bonds between the anions and the hydroxide surface and characteristic binding configurations are determined. Possible effects of LDH on the cell resulting from binding of protein fragments and replacement of native intracellular anions with delivered anions are considered.

Process development for production of coal/sorbent agglomerates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, D.M.

1991-01-01

The goal of this work was to develop a process flow diagram to economically produce a clean-burning fuel from fine Illinois coal. To accomplish this, the process of pelletizing fine coal with calcium hydroxide, a sulfur capturing sorbent, was investigated. Carbonation, which is the reaction of calcium hydroxide with carbon dioxide (in the presence of moisture) to produce a bonding matrix of calcium carbonate, was investigated as a method for improving pellet quality and reducing binder costs. Proper moisture level is critical to allow the reaction to occur. If too much moisture is present in a pellet, the pore spacesmore » are filled and carbon dioxide must diffuse through the water to reach the calcium hydroxide and react. This severely slows or stops the reaction. The ideal situation is when there is just enough moisture to coat the calcium hydroxide allowing for the reaction to proceed. The process has been successfully demonstrated on a pilot-scale as a method of hardening iron ore pellets (Imperato, 1966). Two potential combustion options are being considered for the coal/calcium hydroxide pellets: fluidized bed combustors and industrial stoker boilers.« less

Praseodymium hydroxide and oxide nanorods and Au/Pr6O11 nanorod catalysts for CO oxidation.

PubMed

Huang, P X; Wu, F; Zhu, B L; Li, G R; Wang, Y L; Gao, X P; Zhu, H Y; Yan, T Y; Huang, W P; Zhang, S M; Song, D Y

2006-02-02

Praseodymium hydroxide nanorods were synthesized by a two-step approach: First, metallic praseodymium was used to form praseodymium chloride, which reacted subsequently with KOH solution to produce praseodymium hydroxide. In the second step the hydroxide was treated with a concentrated alkaline solution at 180 degrees C for 45 h, yielding nanorods as shown by the scanning and transmission electron microscopy images. The results of X-ray diffraction and energy-dispersive X-ray spectroscopy experiments indicate that these nanorods are pure praseodymium hydroxide with a hexagonal structure, which can be converted into praseodymium oxide (Pr6O11) nanorods of a face-centered cubic structure after calcination at 600 degrees C for 2 h in air. Gold was loaded on the praseodymium oxide nanorods using HAuCl4 as the gold source, and NaBH4 was used to reduce the gold species to metallic nanoparticles with sizes of 8-12 nm on the nanorod surface. These Au/Pr6O11 nanorods exhibit superior catalytic activity for CO oxidation.

Atomic hydrogen in. gamma. -irradiated hydroxides of alkaline-earth elements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spitsyn, V.I.; Yurik, T.K.; Barsova, L.I.

1982-04-01

Atomic hydrogen is an important intermediate product formed in the radiolysis of compounds containing X-H bonds. H atoms have been detected in irradiated matrices of H/sub 2/ and inert gases at 4/sup 0/K, in irradiated ice and frozen solutions of acids in irradiated salts and in other systems. Here results are presented from a study of the ESR spectra of H atoms generated in polycrystalline hydroxides of alkaline-earth elements that have been ..gamma..-irradiated at 77/sup 0/K, after preliminary treatment at various temperatures. For the first time stabilization of atomic hydrogen in ..gamma..-irradiated polycrystalline alkaline-earth element hydroxides has been detected. Dependingmore » on the degree of dehydroxylation, several types of hydrogen atoms may be stabilized in the hydroxides, these hydrogen atoms having different radiospectroscopic parameters. In the magnesium-calcium-strontium-barium hydroxide series, a regular decrease has been found in the hfi constants for H atoms with the cations in the immediate surroundings. A direct proportionality has been found between the parameters ..delta..A/A/sub 0/ and the polarizability of the cation.« less

Potassium hydroxide poisoning

MedlinePlus

... effectively treat (adsorb) sodium hydroxide. For skin exposure, treatment may include: Surgical removal of burned skin (debridement) Transfer to a hospital that specializes in burn care Washing of the skin (irrigation), possibly every ...

Carbonation of metal silicates for long-term CO.sub.2 sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blencoe, James G.; Palmer, Donald A.; Anovitz, Lawrence M.

In a preferred embodiment, the invention relates to a process of sequestering carbon dioxide. The process comprises the steps of: (a) reacting a metal silicate with a caustic alkali-metal hydroxide to produce a hydroxide of the metal formerly contained in the silicate; (b) reacting carbon dioxide with at least one of a caustic alkali-metal hydroxide and an alkali-metal silicate to produce at least one of an alkali-metal carbonate and an alkali-metal bicarbonate; and (c) reacting the metal hydroxide product of step (a) with at least one of the alkali-metal carbonate and the alkali-metal bicarbonate produced in step (b) to producemore » a carbonate of the metal formerly contained in the metal silicate of step (a).« less

Ultrathin platinum nanowires grown on single-layered nickel hydroxide with high hydrogen evolution activity.

PubMed

Yin, Huajie; Zhao, Shenlong; Zhao, Kun; Muqsit, Abdul; Tang, Hongjie; Chang, Lin; Zhao, Huijun; Gao, Yan; Tang, Zhiyong

2015-03-02

Design and synthesis of effective electrocatalysts for hydrogen evolution reaction in alkaline environments is critical to reduce energy losses in alkaline water electrolysis. Here we report a hybrid nanomaterial comprising of one-dimensional ultrathin platinum nanowires grown on two-dimensional single-layered nickel hydroxide. Judicious surface chemistry to generate the fully exfoliated nickel hydroxide single layers is explored to be the key for controllable growth of ultrathin platinum nanowires with diameters of about 1.8 nm. Impressively, this hybrid nanomaterial exhibits superior electrocatalytic activity for hydrogen evolution reaction in alkaline solution, which outperforms currently reported catalysts, and the obviously improved catalytic stability. We believe that this work may lead towards the development of single-layered metal hydroxide-based hybrid materials for applications in catalysis and energy conversion.

Microwave assisted alkali-catalyzed transesterification of Pongamia pinnata seed oil for biodiesel production.

PubMed

Kumar, Ritesh; Kumar, G Ravi; Chandrashekar, N

2011-06-01

In this study, microwave assisted transesterification of Pongamia pinnata seed oil was carried out for the production of biodiesel. The experiments were carried out using methanol and two alkali catalysts i.e., sodium hydroxide (NaOH) and potassium hydroxide (KOH). The experiments were carried out at 6:1 alcohol/oil molar ratio and 60°C reaction temperature. The effect of catalyst concentration and reaction time on the yield and quality of biodiesel was studied. The result of the study suggested that 0.5% sodium hydroxide and 1.0% potassium hydroxide catalyst concentration were optimum for biodiesel production from P. pinnata oil under microwave heating. There was a significant reduction in reaction time for microwave induced transesterification as compared to conventional heating. Copyright © 2011 Elsevier Ltd. All rights reserved.

21 CFR 172.814 - Hydroxylated lecithin.

Code of Federal Regulations, 2012 CFR

2012-04-01

...) With hydrogen peroxide, benzoyl peroxide, lactic acid, and sodium hydroxide. (2) With hydrogen peroxide, acetic acid, and sodium hydroxide. (b) It is used or intended for use, in accordance with good...

21 CFR 172.814 - Hydroxylated lecithin.

Code of Federal Regulations, 2013 CFR

2013-04-01

...) With hydrogen peroxide, benzoyl peroxide, lactic acid, and sodium hydroxide. (2) With hydrogen peroxide, acetic acid, and sodium hydroxide. (b) It is used or intended for use, in accordance with good...

Amended Ballistic Sand Studies to Provide Low Maintenance Lead Containment at Active Small Arms Firing Range Systems

DTIC Science & Technology

2007-09-01

Pb2+. Under alkaline conditions, elemental lead will oxidize under most circumstances to form a lead hydroxide complex Pb(OH)53-. Lead that exists...lead hydroxide [Pb(OH)2], lead carbonate [PbCO3, cerrusite], or basic lead carbonate [Pb3(OH)2 (CO3)2, hydrocerrusite]. The overall lead solubility...in a natural system is fundamentally determined by the concentrations of the anions in solution (e.g., the hydroxide and carbonate ions) and by the

Determination of soluble bromine in an extra-high-pressure mercury discharge lamp by sodium hydroxide decomposition-suppressed ion chromatography.

PubMed

Mitsumata, Hiroshi; Mori, Toshio; Maeda, Tatsuo; Kita, Yoshiyuki; Kohatsu, Osamu

2006-02-01

We have established a simple method for assaying the quantity of soluble bromine in the discharge tubes of an extra-high-pressure mercury discharge lamp. Each discharge tube is destroyed in 5 ml of 10 mM sodium hydroxide, and the recovered sodium hydroxide solution is analyzed by suppressed-ion chromatography using gradient elution. We have clarified that this method can assay less than 1 microg of soluble bromine in a discharge tube.

21 CFR 82.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-04-01

... hydroxide. (h) The term blanc fixe means a suspension in water of precipitated barium sulfate. (i) The term gloss white means a suspension in water of co-precipitated aluminum hydroxide and barium sulfate. (j...

21 CFR 82.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-04-01

... hydroxide. (h) The term blanc fixe means a suspension in water of precipitated barium sulfate. (i) The term gloss white means a suspension in water of co-precipitated aluminum hydroxide and barium sulfate. (j...

21 CFR 82.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... hydroxide. (h) The term blanc fixe means a suspension in water of precipitated barium sulfate. (i) The term gloss white means a suspension in water of co-precipitated aluminum hydroxide and barium sulfate. (j...

21 CFR 73.2326 - Chromium hydroxide green.

Code of Federal Regulations, 2013 CFR

2013-04-01

... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2326 Chromium hydroxide green. (a) Identity and... in coloring externally applied cosmetics, including those intended for use in the area of the eye, in...

21 CFR 73.2326 - Chromium hydroxide green.

Code of Federal Regulations, 2014 CFR

2014-04-01

... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2326 Chromium hydroxide green. (a) Identity and... in coloring externally applied cosmetics, including those intended for use in the area of the eye, in...

21 CFR 73.2326 - Chromium hydroxide green.

Code of Federal Regulations, 2012 CFR

2012-04-01

... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2326 Chromium hydroxide green. (a) Identity and... in coloring externally applied cosmetics, including those intended for use in the area of the eye, in...

27 CFR 21.63 - Formula No. 36.

Code of Federal Regulations, 2012 CFR

2012-04-01

... pounds of caustic soda, liquid grade, containing 50 percent sodium hydroxide by weight; or 12.0 pounds of caustic soda, liquid grade, containing 73 percent sodium hydroxide by weight. (b) Authorized uses. (1) As...

27 CFR 21.63 - Formula No. 36.

Code of Federal Regulations, 2014 CFR

2014-04-01

... pounds of caustic soda, liquid grade, containing 50 percent sodium hydroxide by weight; or 12.0 pounds of caustic soda, liquid grade, containing 73 percent sodium hydroxide by weight. (b) Authorized uses. (1) As...

27 CFR 21.63 - Formula No. 36.

Code of Federal Regulations, 2013 CFR

2013-04-01

... pounds of caustic soda, liquid grade, containing 50 percent sodium hydroxide by weight; or 12.0 pounds of caustic soda, liquid grade, containing 73 percent sodium hydroxide by weight. (b) Authorized uses. (1) As...

21 CFR 172.814 - Hydroxylated lecithin.

Code of Federal Regulations, 2014 CFR

2014-04-01

... resultant product has an acetyl value of 30 to 38: (1) With hydrogen peroxide, benzoyl peroxide, lactic acid, and sodium hydroxide. (2) With hydrogen peroxide, acetic acid, and sodium hydroxide. (b) It is used or...

A New Look at the Role of Thiolate Ligation in Cytochrome P450

PubMed Central

Yosca, Timothy H.; Ledray, Aaron P.; Ngo, Joanna; Green, Michael T.

2017-01-01

Protonated ferryl (or iron(IV)hydroxide) intermediates have been characterized in several thiolate-ligated heme proteins that are known to catalyze C-H bond activation. The basicity of the ferryl intermediates in these species has been proposed to play a critical role in facilitating this chemistry, allowing hydrogen abstraction at reduction potentials below those that would otherwise lead to oxidative degradation of the enzyme. In this contribution, we discuss the events that led to the assignment and characterization of the unusual iron(IV)hydroxide species, highlighting experiments that provided a quantitative measure of the ferryl basicity, the iron(IV)hydroxide pKa. We then turn to the importance of the iron(IV)hydroxide state, presenting a new way of looking at the role of thiolate ligation in these systems. PMID:28091754

Sodium hydroxide catalyzed monodispersed high surface area silica nanoparticles.

PubMed

Bhakta, Snehasis; Dixit, Chandra K; Bist, Itti; Jalil, Karim Abdel; Suib, Steven L; Rusling, James F

2016-07-01

Understanding of the synthesis kinetics and our ability to modulate medium conditions allowed us to generate nanoparticles via an ultra-fast process. The synthesis medium is kept quite simple with tetraethyl orthosilicate (TEOS) as precursor and 50% ethanol and sodium hydroxide catalyst. Synthesis is performed under gentle conditions at 20 °C for 20 min Long synthesis time and catalyst-associated drawbacks are most crucial in silica nanoparticle synthesis. We have addressed both these bottlenecks by replacing the conventional Stober catalyst, ammonium hydroxide, with sodium hydroxide. We have reduced the overall synthesis time from 20 to 1/3 h, ~60-fold decrease, and obtained highly monodispersed nanoparticles with 5-fold higher surface area than Stober particles. We have demonstrated that the developed NPs with ~3-fold higher silane can be used as efficient probes for biosensor applications.

Method for making polysilsesquioxanes and organohydridosilanes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loy, Douglas A.; Rahimian, Kamyar

2001-01-01

A method for disproportionation of an oligohydridosiloxane to produce a polysilsesquioxane compound and an organohydridosilane compound when contacted with a basic catalyst. The basic catalyst can be a tetraalkylammonium hydroxide, an alkali metal hydroxide, and an alkali earth hydroxide. These basic catalysts are generally dissolved in an organic solvent for delivery. The hydroxide catalysts are attractive because many readily decompose by heating above 150.degree. C., thus being easily removed from the final materials. The oligohydridosiloxane is contacted with the basic catalyst under conditions effective to catalytically convert the oligohydridosiloxane into a polysilsesquioxane compound and an organohydridosilane compound. The reaction canmore » occur in either an inert or oxidative atmosphere and can occur without heating, at room temperature. Both polysilsesquioxane foams and gels of the formula (RSiO.sub.1.5).sub.n can be produced.« less

Transformation of zinc hydroxide chloride monohydrate to crystalline zinc oxide.

PubMed

Moezzi, Amir; Cortie, Michael; McDonagh, Andrew

2016-04-25

Thermal decomposition of layered zinc hydroxide double salts provides an interesting alternative synthesis for particles of zinc oxide. Here, we examine the sequence of changes occurring as zinc hydroxide chloride monohydrate (Zn5(OH)8Cl2·H2O) is converted to crystalline ZnO by thermal decomposition. The specific surface area of the resultant ZnO measured by BET was 1.3 m(2) g(-1). A complicating and important factor in this process is that the thermal decomposition of zinc hydroxide chloride is also accompanied by the formation of volatile zinc-containing species under certain conditions. We show that this volatile compound is anhydrous ZnCl2 and its formation is moisture dependent. Therefore, control of atmospheric moisture is an important consideration that affects the overall efficiency of ZnO production by this process.

Forms of adsorption and transition states of oxidation of carbon monoxide by molecular oxygen and dissociation of nitrogen monooxide, catalyzed by monovalent copper

NASA Astrophysics Data System (ADS)

Ermakov, A. I.; Mashutin, V. Y.; Vishnjakov, A. V.

With the help of the results of semiempirical (parametric method 3) and ab initio (second-order Møller-Plesset [MP2] unrestricted Hartree-Fock [UHF] 6-31G**, unrestricted density functional theory [UDFT] 6-31G** Becke's three-parameter exchange functional and the gradient-corrected functional of Lee, Yang, and Paar [B3LYP] and UDFT LANL2DZ B3LYP) quantum-chemical calculations has been studied the complexation CO and NO with molecular hydroxide of copper(I). The influence of charge defects has been simulated by the calculations of anionic, neutral, and cationic systems. It is shown that CO and NO are mainly coordinated by nonoxygen atom on an atom of copper(I) hydroxide as one- and two-center forms. These forms are suitable for appearance of prereactionary complexes of catalytic oxidation CO by molecular oxygen and decomposition NO into atoms of nitrogen and oxygen. The corresponding prereactionary complexes for systems with participation of copper(II) hydroxide and copper(III) hydroxide are not revealed. The calculations predict inhibiting impact of copper(II) and copper(III) of the observed reactions. Computed stability of complexes CO and NO with copper(I) hydroxide and activation energy of catalytic conversion of monooxides essentially depend on an excessive charge of the system. Introduction of electron-donating additives into copper(I) hydroxide promotes rise of catalytic activity of copper(I) compound.

Sulphate removal from sodium sulphate-rich brine and recovery of barium as a barium salt mixture.

PubMed

Vadapalli, Viswanath R K; Zvimba, John N; Mulopo, Jean; Motaung, Solly

2013-01-01

Sulphate removal from sodium sulphate-rich brine using barium hydroxide and recovery of the barium salts has been investigated. The sodium sulphate-rich brine treated with different dosages of barium hydroxide to precipitate barium sulphate showed sulphate removal from 13.5 g/L to less than 400 mg/L over 60 min using a barium to sulphate molar ratio of 1.1. The thermal conversion of precipitated barium sulphate to barium sulphide achieved a conversion yield of 85% using coal as both a reducing agent and an energy source. The recovery of a pure mixture of barium salts from barium sulphide, which involved dissolution of barium sulphide and reaction with ammonium hydroxide resulted in recovery of a mixture of barium carbonate (62%) and barium hydroxide (38%), which is a critical input raw material for barium salts based acid mine drainage (AMD) desalination technologies. Under alkaline conditions of this barium salt mixture recovery process, ammonia gas is given off, while hydrogen sulfide is retained in solution as bisulfide species, and this provides basis for ammonium hydroxide separation and recovery for reuse, with hydrogen sulfide also recoverable for further industrial applications such as sulfur production by subsequent stripping.

Hydrated proton and hydroxide charge transfer at the liquid/vapor interface of water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soniat, Marielle; Rick, Steven W., E-mail: srick@uno.edu; Kumar, Revati

2015-07-28

The role of the solvated excess proton and hydroxide ions in interfacial properties is an interesting scientific question with applications in a variety of aqueous behaviors. The role that charge transfer (CT) plays in interfacial behavior is also an unsettled question. Quantum calculations are carried out on clusters of water with an excess proton or a missing proton (hydroxide) to determine their CT. The quantum results are applied to analysis of multi-state empirical valence bond trajectories. The polyatomic nature of the solvated excess proton and hydroxide ion results in directionally dependent CT, depending on whether a water molecule is amore » hydrogen bond donor or acceptor in relation to the ion. With polyatomic molecules, CT also depends on the intramolecular bond distances in addition to intermolecular distances. The hydrated proton and hydroxide affect water’s liquid/vapor interface in a manner similar to monatomic ions, in that they induce a hydrogen-bonding imbalance at the surface, which results in charged surface waters. This hydrogen bond imbalance, and thus the charged waters at the surface, persists until the ion is at least 10 Å away from the interface.« less

Continuous-flow extraction system for elemental association study: a case of synthetic metal-doped iron hydroxide.

PubMed

Hinsin, Duangduean; Pdungsap, Laddawan; Shiowatana, Juwadee

2002-12-06

A continuous-flow extraction system originally developed for sequential extraction was applied to study elemental association of a synthetic metal-doped amorphous iron hydroxide phase. The homogeneity and metal association of the precipitates were evaluated by gradual leaching using the system. Leachate was collected in fractions for determination of elemental concentrations. The result obtained as extractograms indicated that the doped metals were adsorbed more on the outermost surface rather than homogeneously distributed in the precipitates. The continuous-flow extraction method was also used for effective removal of surface adsorbed metals to obtain a homogeneous metal-doped synthetic iron hydroxide by a sequential extraction using acetic acid and small volume of hydroxylamine hydrochloride solution. The system not only ensures complete washing, but the extent of metal immobilization in the synthetic iron hydroxide could be determined with high accuracy from the extractograms. The initial metal/iron mole ratio (M/Fe) in solution affected the M/Fe mole ratio in homogeneous doped iron hydroxide phase. The M/Fe mole ratio of metal incorporation was approximately 0.01-0.02 and 0.03-0.06, for initial solution M/Fe mole ratio of 0.025 and 0.100, respectively.

Chemical matricectomy with 10% sodium hydroxide for the treatment of ingrown toenails in people with diabetes.

PubMed

Tatlican, Semih; Eren, Cemile; Yamangokturk, Burcu; Eskioglu, Fatma; Bostanci, Seher

2010-02-01

Treatment of ingrown toenails using chemical matricectomy in patients with diabetes has been difficult, because delayed wound healing, wound infections, and digital ischemia can interfere with the procedure. Chemical matricectomy with 10% sodium hydroxide is an effective treatment for ingrown toenails in a normal population. Investigation of the effectiveness and safety of chemical matricectomy with 10% sodium hydroxide solution for ingrown toenails in patients with diabetes. Thirty patients with diabetes with 40 ingrown toenails and 30 patients without diabetes with 41 ingrown toenails were enrolled in the study. After partial avulsion of the affected edge, germinal matrix was treated for 1 minute with 10% sodium hydroxide. Patients were observed on alternate days until complete healing was achieved and followed for up to 24 months for recurrence. Assessment of the treatment in both groups for complete healing, postoperative pain, tissue damage, drainage, infections, and rate of recurrences revealed no statistically significant difference. The partial avulsion of the affected edge and the treatment of the germinal matrix for 1 minute with 10% sodium hydroxide preceded by matrix curettage is an effective and safe treatment modality for ingrown toenails in people with diabetes.

Process development for production of coal/sorbent agglomerates. Final technical report, September 1, 1990--August 31, 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, D.M.

1991-12-31

The goal of this work was to develop a process flow diagram to economically produce a clean-burning fuel from fine Illinois coal. To accomplish this, the process of pelletizing fine coal with calcium hydroxide, a sulfur capturing sorbent, was investigated. Carbonation, which is the reaction of calcium hydroxide with carbon dioxide (in the presence of moisture) to produce a bonding matrix of calcium carbonate, was investigated as a method for improving pellet quality and reducing binder costs. Proper moisture level is critical to allow the reaction to occur. If too much moisture is present in a pellet, the pore spacesmore » are filled and carbon dioxide must diffuse through the water to reach the calcium hydroxide and react. This severely slows or stops the reaction. The ideal situation is when there is just enough moisture to coat the calcium hydroxide allowing for the reaction to proceed. The process has been successfully demonstrated on a pilot-scale as a method of hardening iron ore pellets (Imperato, 1966). Two potential combustion options are being considered for the coal/calcium hydroxide pellets: fluidized bed combustors and industrial stoker boilers.« less

Comparative evaluation of antimicrobial efficacy of various root canal filling materials along with aloevera used in primary teeth: a microbiological study.

PubMed

Kriplani, R; Thosar, N; Baliga, M S; Kulkarni, P; Shah, N; Yeluri, R

2013-01-01

this study was conducted to evaluate the antimicrobial effectiveness of 6 root canal filling materials and a negative control agent against 18 strains of bacteria isolated from infected root canals of primary molar teeth using agar diffusion assay. Aloevera with sterile water Zinc oxide and Eugenol, Zinc oxide-Eugenol with aloevera, Calcium hydroxide and sterile water, Calcium hydroxide with sterile water and aloevera, Calcium hydroxide and Iodoform (Metapex) and Vaseline (Control). MIC and MBC of aloevera was calculated. All materials except Vaseline showed varied antimicrobial activity against the test bacterias. The zones of inhibition were ranked into 4 inhibition categories based on the proportional distribution of the data. All the 18 bacterial isolates were classified under 2 groups based on Gram positive and Gram negative aerobes. Statistical analysis was carried out to compare the antimicrobial effectiveness between materials tested with each of the bacterial groupings. Aloevera + Sterile Water was found to have superior antimicrobial activity against most of the microorganisms followed by ZOE + Aloevera, calcium hydroxide + Aloevera, ZOE, calcium hydroxide, Metapex in the descending order and Vaseline showed no inhibition.

Hydroxide catalysts for lignin depolymerization

DOEpatents

Beckham, Gregg T; Biddy, Mary J.; Kruger, Jacob S.; Chmely, Stephen C.; Sturgeon, Matthew

2017-10-17

Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

Studies of the Codeposition of Cobalt Hydroxide and Nickel Hydroxide

NASA Technical Reports Server (NTRS)

Ho, C. H.; Murthy, M.; VanZee, J. W.

1997-01-01

Topics considered include: chemistry, experimental measurements, planar film model development, impregnation model development, results and conclusion. Also included: effect of cobalt concentration on deposition/loading; effect of current density on loading distribution.

Hydroxide catalysts for lignin depolymerization

DOEpatents

Beckham, Gregg T.; Biddy, Mary J.; Chmely, Stephen C.; Sturgeon, Matthew

2017-04-25

Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

Provisional Peer-Reviewed Toxicity Values for Rubidium Compounds (Rubidium Hydroxide)

EPA Science Inventory

This is a PPRTV for Rubidium Compounds submitted to the Superfund Program.This assessment supports multiple isomers (see related links) and this page is about the chemical rubidium hydroxide, CASRN 1310-82-3.

Process for preparing active oxide powders

DOEpatents

Berard, Michael F.; Hunter, Jr., Orville; Shiers, Loren E.; Dole, Stephen L.; Scheidecker, Ralph W.

1979-02-20

An improved process for preparing active oxide powders in which cation hydroxide gels, prepared in the conventional manner are chemically dried by alternately washing the gels with a liquid organic compound having polar characteristics and a liquid organic compound having nonpolar characteristics until the mechanical water is removed from the gel. The water-free cation hydroxide is then contacted with a final liquid organic wash to remove the previous organic wash and speed drying. The dried hydroxide treated in the conventional manner will form a highly sinterable active oxide powder.

Studies on Thorium Adsorption Characteristics upon Activated Titanium Hydroxide Prepared from Rosetta Ilmenite Concentrate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gado, M, E-mail: parq28@yahoo.com; Zaki, S

2016-01-01

The titanium hydroxide prepared from Rosetta ilmenite concentrate has been applied for Th (IV) adsorption from its acid aqueous solutions. The prepared hydroxide is first characterized by both Fourier transform infrared (FT-IR) spectrum and thermogravimetric analysis. The relevant factors affecting the adsorption process have been studied. The obtained equilibrium data fits well with the Langmuir isotherm rather than Freundlich isotherm, while the adsorption kinetic data follow the pseudo-second order model. The different thermodynamic parameters have also been calculated and indicate that the adsorption process is spontaneous.

Interactions of Water Vapor with Oxides at Elevated Temperatures

NASA Technical Reports Server (NTRS)

Jacobson, Nathan; Opila, Elizabeth; Copland, Evan; Myers, Dwight

2003-01-01

Many volatile metal hydroxides form by reaction of the corresponding metal oxide with water vapor. These reactions are important in a number of high temperature corrosion processes. Experimental methods for studying the thermodynamics of metal hydroxides include: gas leak Knudsen cell mass spectrometry, free jet sampling mass spectrometry, transpiration and hydrogen-oxygen flame studies. The available experimental information is reviewed and the most stable metal hydroxide species are correlated with position in the periodic table. Current studies in our laboratory on the Si-O-H system are discussed.

Fly ash/Kaolin based geopolymer green concretes and their mechanical properties

PubMed Central

Okoye, F.N.; Durgaprasad, J.; Singh, N.B.

2015-01-01

Geopolymer concrete mixes were cast using fly ash, kaolin, sodium hydroxide, potassium hydroxide, sodium silicate and aggregates. Portland cement concrete (M30) was used as a reference sample. The effect of silica fume, temperature (40 °C, 60 °C, 80 °C, 100 °C and 120 °C), sodium and potassium hydroxides and different superplasticizers on the compressive strength are reported [1]. Maximum strength was found at 100 °C and 14 M alkali solution [1]. PMID:26693505

Fly ash/Kaolin based geopolymer green concretes and their mechanical properties.

PubMed

Okoye, F N; Durgaprasad, J; Singh, N B

2015-12-01

Geopolymer concrete mixes were cast using fly ash, kaolin, sodium hydroxide, potassium hydroxide, sodium silicate and aggregates. Portland cement concrete (M30) was used as a reference sample. The effect of silica fume, temperature (40 °C, 60 °C, 80 °C, 100 °C and 120 °C), sodium and potassium hydroxides and different superplasticizers on the compressive strength are reported [1]. Maximum strength was found at 100 °C and 14 M alkali solution [1].

Application of nanodimensional particles and aluminum hydroxide nanostructures for cancer diagnosis and therapy

NASA Astrophysics Data System (ADS)

Korovin, M. S.; Fomenko, A. N.

2017-09-01

Nanoparticles and nanostructured materials are one of the most promising developments for cancer therapy. Gold nanoparticles, magnetic nanoparticles based on iron and its oxides and other metal oxides have been widely used in diagnosis and treatment of cancer. Much less researchers' attention has been paid to nanoparticles and nanostructures based on aluminum oxides and hydroxides as materials for cancer diagnosis and treatment. However, recent investigations have shown promising results regarding these objects. Here, we review the antitumor results obtained with different aluminum oxide/hydroxide nanoparticles and nanostructures.

Method of manufacturing positive nickel hydroxide electrodes

DOEpatents

Gutjahr, M.A.; Schmid, R.; Beccu, K.D.

1975-12-16

A method of manufacturing a positive nickel hydroxide electrode is discussed. A highly porous core structure of organic material having a fibrous or reticular texture is uniformly coated with nickel powder and then subjected to a thermal treatment which provides sintering of the powder coating and removal of the organic core material. A consolidated, porous nickel support structure is thus produced which has substantially the same texture and porosity as the initial core structure. To provide the positive electrode including the active mass, nickel hydroxide is deposited in the pores of the nickel support structure.

Pilot Plant Makes Oxygen Difluoride

NASA Technical Reports Server (NTRS)

Humphrey, Marshall F.; Lawton, Emil A.

1989-01-01

Pilot plant makes oxygen difluoride highly-energetic, space-storable oxidizer not made commercially. Designed to handle reactants, product, and byproduct, most of which highly reactive, corrosive, and toxic. Oxygen difluoride evolves continuously from reactor containing potassium hydroxide in water at 10 degree C. Collection tanks alternated; one filled while other drained to storage cylinder. Excess OF2 and F2 dissipated in combustion of charcoal in burn barrel. Toxic byproduct, potassium fluoride, reacted with calcium hydroxide to form nontoxic calcium fluoride and to regenerate potassium hydroxide. Equipment processes toxic, difficult-to-make substance efficiently and safely.

Interaction of almond cystatin with pesticides: Structural and functional analysis.

PubMed

Siddiqui, Azad Alam; Khaki, Peerzada Shariq Shaheen; Bano, Bilqees

2017-03-01

Pesticides are chemical substances that eliminate or control a variety of agricultural pests that damage crops and livestock. They not only affect the targeted pests but also affect the nontargeted systems, raising more concerns for their effect on both plant and animal systems. Cystatins (cysteine protease inhibitor) are ubiquitously present in all living cells and show a variety of important physiological functions. The present study shows the effect of different pesticides (pendimethalin, methoxyfenozide, and Cu II hydroxide) on purified almond cystatin. Almond cystatin showed concentration-dependent loss in papain inhibitory activity on interaction with the pesticides, showing maximum loss in the presence of Cu(II) hydroxide and minimum in the case of methoxyfenozide. Native polyacrylamide gel electrophoresis showed maximum degradation of purified cystatin in the presence of Cu(II) hydroxide with insignificant effect in the presence of methoxyfenozide. Structural alterations were significant in the case of Cu(II) hydroxide and less in the case of methoxyfenozide as revealed by UV and fluorescence spectral studies. Secondary structural alterations were further conformed by circular dichroism and Fourier transform infrared spectroscopy. The α-helix content of almond cystatin decreases from 35.64% (native) to 34.83%, 30.79%, and 29.62% for methoxyfenozide-, pendimethalin-, and Cu(II) hydroxide-treated cystatin, respectively. A Fourier transform infrared study shows an amide I band shift for almond cystatin from 1649.15 ± 0.5 to 1646.48 ± 0.6, 1640.44 ± 0.6, and 1635.11 ± 0.3 cm -1 for methoxyfenozide, pendimethalin, and Cu(II) hydroxide, respectively. Values obtained for different thermodynamic parameters (ΔH 0 , ΔG 0 , N, and ΔS 0 ) by isothermal titration calorimetric experiments reveal maximum binding of almond cystatin with Cu(II) hydroxide followed by pendimethalin and little interaction with methoxyfenozide. Copyright © 2016 John Wiley & Sons, Ltd.

78 FR 3967 - Notice of Application for Special Permits

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-17

...). transportation in Branchburg, NJ. commerce of PG II corrosive materials described as Potassium Hydroxide Solution, UN 1814 and Sodium Hydroxide Solution, UN 1824 in a UN 50G Fiberboard Large Packaging. (modes 1, 2, 3...

Positive electrodes of nickel-cadmium batteries

NASA Technical Reports Server (NTRS)

Wabner, D. W.; Kandler, L.; Krienke, W.

1985-01-01

Ni hydroxide sintered electrodes which are filled electrochemically are superior to chemically treated electrodes. In the electrochemical process, the hydroxide grows on the Ni grains and possesses a well-defined porous structure. Diffusion and conducting mechanisms are therefore facilitated.

68. INTERIOR VIEW LOOKING OF THE CAUSTIC SODA (SODIUM HYDROXIDE) ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

68. INTERIOR VIEW LOOKING OF THE CAUSTIC SODA (SODIUM HYDROXIDE) BUILDING, LOOKING AT CAUSTIC SODA MEASURING TANKS. (DATE UNKNOWN). - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

Antimycobacterial, antimicrobial, and biocompatibility properties of para-aminosalicylic acid with zinc layered hydroxide and Zn/Al layered double hydroxide nanocomposites

PubMed Central

Saifullah, Bullo; El Zowalaty, Mohamed E; Arulselvan, Palanisamy; Fakurazi, Sharida; Webster, Thomas J; Geilich, Benjamin M; Hussein, Mohd Zobir

2014-01-01

The treatment of tuberculosis by chemotherapy is complicated due to multiple drug prescriptions, long treatment duration, and adverse side effects. We report here for the first time an in vitro therapeutic effect of nanocomposites based on para-aminosalicylic acid with zinc layered hydroxide (PAS-ZLH) and zinc-aluminum layered double hydroxides (PAS-Zn/Al LDH), against mycobacteria, Gram-positive bacteria, and Gram-negative bacteria. The nanocomposites demonstrated good antimycobacterial activity and were found to be effective in killing Gram-positive and Gram-negative bacteria. A biocompatibility study revealed good biocompatibility of the PAS-ZLH nanocomposites against normal human MRC-5 lung cells. The para-aminosalicylic acid loading was quantified with high-performance liquid chromatography analysis. In summary, the present preliminary in vitro studies are highly encouraging for further in vivo studies of PAS-ZLH and PAS-Zn/Al LDH nanocomposites to treat tuberculosis. PMID:25114509

Benchmarking polarizable molecular dynamics simulations of aqueous sodium hydroxide by diffraction measurements.

PubMed

Vácha, Robert; Megyes, Tunde; Bakó, Imre; Pusztai, László; Jungwirth, Pavel

2009-04-23

Results from molecular dynamics simulations of aqueous hydroxide of varying concentrations have been compared with experimental structural data. First, the polarizable POL3 model was verified against neutron scattering using a reverse Monte Carlo fitting procedure. It was found to be competitive with other simple water models and well suited for combining with hydroxide ions. Second, a set of four polarizable models of OH- were developed by fitting against accurate ab initio calculations for small hydroxide-water clusters. All of these models were found to provide similar results that robustly agree with structural data from X-ray scattering. The present force field thus represents a significant improvement over previously tested nonpolarizable potentials. Although it cannot in principle capture proton hopping and can only approximately describe the charge delocalization within the immediate solvent shell around OH-, it provides structural data that are almost entirely consistent with data obtained from scattering experiments.

Comparison of sodium hydroxide and calcium hydroxide pretreatments on the enzymatic hydrolysis and lignin recovery of sugarcane bagasse.

PubMed

Chang, Menglei; Li, Denian; Wang, Wen; Chen, Dongchu; Zhang, Yuyuan; Hu, Huawen; Ye, Xiufang

2017-11-01

Sodium hydroxide (NaOH) and calcium hydroxide (Ca(OH) 2 ) respectively dissolved in water and 70% glycerol were applied to treat sugarcane bagasse (SCB) under the condition of 80°C for 2h. NaOH solutions could remove more lignin and obtain higher enzymatic hydrolysis efficiency of SCB than Ca(OH) 2 solutions. Compared with the alkali-water solutions, the enzymatic hydrolysis of SCB treated in NaOH-glycerol solution decreased, while that in Ca(OH) 2 -glycerol solution increased. The lignin in NaOH-water pretreatment liquor could be easily recovered by calcium chloride (CaCl 2 ) at room temperature, but that in Ca(OH) 2 -water pretreatment liquor couldn't. NaOH pretreatment is more suitable for facilitating enzymatic hydrolysis and lignin recovery of SCB than Ca(OH) 2 pretreatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Alkalization of tumor microenvironment for cancer treatment

NASA Astrophysics Data System (ADS)

Lozhkomoev, A. S.

2017-09-01

The paper is devoted to describing how boehmite, magnesium hydroxide and calcium hydroxide nanoparticles in the form of nanoplates with a size of 20-200 nm having cytotoxic properties to tumor cells were synthesized. It is shown that calcium hydroxide has the highest cytotoxicity, while boehmite has the lowest one. The characterization of the synthesized nanostructures demonstrated that the major antitumor factors probably are the acid-base surface properties. It is established that calcium hydroxide raises the pH of the cell culture medium up to 12.8, magnesium hydroxide—up to 10.8, boehmite—up to 8.6. At the same time, synthesized nanoplates are less toxic to the normal cell lines. The approach presented can be used for synthesis of materials that are able to change tumor cells microenvironment acidity in the defined range for anticancer therapy, and also potentiating standard chemotherapy drugs effect due to extracellular acidosis decreasing.

New metal phthalocyanines/metal simple hydroxide multilayers: experimental evidence of dipolar field-driven magnetic behavior.

PubMed

Bourzami, Riadh; Eyele-Mezui, Séraphin; Delahaye, Emilie; Drillon, Marc; Rabu, Pierre; Parizel, Nathalie; Choua, Sylvie; Turek, Philippe; Rogez, Guillaume

2014-01-21

A series of new hybrid multilayers has been synthesized by insertion-grafting of transition metal (Cu(II), Co(II), Ni(II), and Zn(II)) tetrasulfonato phthalocyanines between layers of Cu(II) and Co(II) simple hydroxides. The structural and spectroscopic investigations confirm the formation of new layered hybrid materials in which the phthalocyanines act as pillars between the inorganic layers. The magnetic investigations show that all copper hydroxide-based compounds behave similarly, presenting an overall antiferromagnetic behavior with no ordering down to 1.8 K. On the contrary, the cobalt hydroxide-based compounds present a ferrimagnetic ordering around 6 K, regardless of the nature of the metal phthalocyanine between the inorganic layers. The latter observation points to strictly dipolar interactions between the inorganic layers. The amplitude of the dipolar field has been evaluated from X-band and Q-band EPR spectroscopy investigation (Bdipolar ≈ 30 mT).

Bubble nucleation and migration in a lead-iron hydr(oxide) core-shell nanoparticle

DOE PAGES

Niu, Kaiyang; Frolov, Timofey; Xin, Huolin L.; ...

2015-10-05

Iron hydroxide is found in a wide range of contexts ranging from biominerals to steel corrosion, and it can transform to anhydrous oxide via releasing O 2 gas and H 2O. However, it is not well understood how gases transport through a crystal lattice. Here, we present in situ observation of the nucleation and migration of gas bubbles in iron (hydr)oxide using transmission electron microscopy. We create Pb–FeOOH model core–shell nanoparticles in a liquid cell. Under electron irradiation, iron hydroxide transforms to iron oxide, during which bubbles are generated, and they migrate through the shell to the nanoparticle surface. Geometricmore » phase analysis of the shell lattice shows an inhomogeneous stain field at the bubbles. In conclusion, our modeling suggests that the elastic interaction between the core and the bubble provides a driving force for bubble migration.« less

Bubble nucleation and migration in a lead–iron hydr(oxide) core–shell nanoparticle

PubMed Central

Niu, Kaiyang; Frolov, Timofey; Xin, Huolin L.; Wang, Junling; Asta, Mark; Zheng, Haimei

2015-01-01

Iron hydroxide is found in a wide range of contexts ranging from biominerals to steel corrosion, and it can transform to anhydrous oxide via releasing O2 gas and H2O. However, it is not well understood how gases transport through a crystal lattice. Here, we present in situ observation of the nucleation and migration of gas bubbles in iron (hydr)oxide using transmission electron microscopy. We create Pb–FeOOH model core–shell nanoparticles in a liquid cell. Under electron irradiation, iron hydroxide transforms to iron oxide, during which bubbles are generated, and they migrate through the shell to the nanoparticle surface. Geometric phase analysis of the shell lattice shows an inhomogeneous stain field at the bubbles. Our modeling suggests that the elastic interaction between the core and the bubble provides a driving force for bubble migration. PMID:26438864

Ultra precision and reliable bonding method

NASA Technical Reports Server (NTRS)

Gwo, Dz-Hung (Inventor)

2001-01-01

The bonding of two materials through hydroxide-catalyzed hydration/dehydration is achieved at room temperature by applying hydroxide ions to at least one of the two bonding surfaces and by placing the surfaces sufficiently close to each other to form a chemical bond between them. The surfaces may be placed sufficiently close to each other by simply placing one surface on top of the other. A silicate material may also be used as a filling material to help fill gaps between the surfaces caused by surface figure mismatches. A powder of a silica-based or silica-containing material may also be used as an additional filling material. The hydroxide-catalyzed bonding method forms bonds which are not only as precise and transparent as optical contact bonds, but also as strong and reliable as high-temperature frit bonds. The hydroxide-catalyzed bonding method is also simple and inexpensive.

Rare earth and zinc layered hydroxide salts intercalated with the 2-aminobenzoate anion as organic luminescent sensitizer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cursino, Ana Cristina Trindade, E-mail: anacursino@ufpr.br; Rives, Vicente, E-mail: vrives@usal.es; Arizaga, Gregorio Guadalupe Carbajal, E-mail: gregoriocarbajal@yahoo.com.mx

2015-10-15

Rare earth (RE = Eu, Y and Tb) and zinc layered hydroxide salts intercalated with nitrate anions were synthesized, followed by exchange with 2-aminobenzoate. The UV absorption ability was improved after intercalation/grafting in relation to that shown by the parent material. - Highlights: • Rare earth (RE = Eu, Y and Tb) and zinc layered hydroxide were synthesized. • Intercalated nitrate anions were exchanged by 2-aminobenzoate. • In all the 2-aminobenzoate containing compounds, the grafting reaction was detected. • The UV absorption ability was improved after the exchange reactions. • Rare earth hydroxide salts are potential matrixes to produce luminescentmore » materials. - Abstract: Rare earth (RE = Eu, Y and Tb) and zinc layered hydroxide salts intercalated with nitrate anions were synthesized, followed by exchange with 2-aminobenzoate. The obtained compounds were characterized by powder X-ray diffraction (PXRD), Fourier transform infrared (FTIR) and ultraviolet visible (UV–vis) spectroscopies, fluorescence measurements and thermal analysis (TGA/DTA). The results from FTIR spectroscopy suggest a direct coordination of 2-aminobenzoate to the metal cations of the inorganic layered structure. The organic derivative products from the intercalation reactions absorb a broader range of UV-light in relation to that shown by the parent material; the photoluminescence measurements present a strong violet, blue and green luminescence under UV-light excitation for layered compounds with, Zn, Y and Tb, respectively. Rare earth hydroxide salts (RE-LHS) are potential alternative matrices for the immobilization of organic species to produce luminescent materials.« less

The effectiveness of sodium hydroxide (NaOH) and sodium carbonate (Na2CO3) on the impurities removal of saturated salt solution

NASA Astrophysics Data System (ADS)

Pujiastuti, C.; Ngatilah, Y.; Sumada, K.; Muljani, S.

2018-01-01

Increasing the quality of salt can be done through various methods such as washing (hydro-extraction), re-crystallization, ion exchange methods and others. In the process of salt quality improvement by re-crystallization method where salt product diluted with water to form saturated solution and re-crystallized through heating process. The quality of the salt produced is influenced by the quality of the dissolved salt and the crystallization mechanism applied. In this research is proposed a concept that before the saturated salt solution is recrystallized added a chemical for removal of the impurities such as magnesium ion (Mg), calcium (Ca), potassium (K) and sulfate (SO4) is contained in a saturated salt solution. The chemical reagents that used are sodium hydroxide (NaOH) 2 N and sodium carbonate (Na2CO3) 2 N. This research aims to study effectiveness of sodium hydroxide and sodium carbonate on the impurities removal of magnesium (Mg), calcium (Ca), potassium (K) and sulfate (SO4). The results showed that the addition of sodium hydroxide solution can be decreased the impurity ions of magnesium (Mg) 95.2%, calcium ion (Ca) 45%, while the addition of sodium carbonate solution can decreased magnesium ion (Mg) 66.67% and calcium ion (Ca) 77.5%, but both types of materials are not degradable sulfate ions (SO4). The sodium hydroxide solution more effective to decrease magnesium ion than sodium carbonate solution, and the sodium carbonate solution more effective to decrease calcium ion than sodium hydroxide solution.

Butanolysis: Comparison of potassium hydroxide and potassium tert-butoxide as catalyst for biodiesel preparing from rapeseed oil.

PubMed

Musil, Martin; Skopal, Frantisek; Hájek, Martin; Vavra, Ales

2018-07-15

Biodiesel is a mixture of esters of fatty acids (most often palmitic, stearic and oleic) and lower alcohols (in our work butanol) produced by transesterification. It is a renewable source of energy, prepared from triacylglycerides, which are contained in vegetable oils and animal fats. This work focuses on alkaline catalyzed transesterification of rapeseed oil with butanol and comparison of two catalysts (potassium hydroxide and potassium tert-butoxide). In industry is usually transesterification of rapeseed oil carried out like reaction catalyzed by potassium hydroxide. Potassium hydroxide have high content of K 2 CO 3 , KHCO 3 and water. Moreover water is formed by neutralization of potassium hydroxide with free fatty acids contained in oil. In cause of tert-butoxide catalyzed reaction, it is not possible because tert-butoxide have not a OH - aniont, which is needed for water forming. The influence of various conditions (addition of water, temperature of separation, intensity of stirring and type of catalyst) on butanolysis process was studied for both catalysts. For both catalysts dependence of conversions on time were plotted. When tert-butoxide was used, satisfactory phase separation was not achieved. The only way was separation of hot crude reaction mixture without adding water. Ester formed by this method had high content of free glycerol and soaps, but reached higher conversion. The best results were obtained with KOH and subsequent separation of cold crude reaction mixture with the addition of water and slow stirring. The difference between reactions catalyzed by potassium hydroxide and potassium tert-butoxide was described. Copyright © 2018 Elsevier Ltd. All rights reserved.

Improving the quality of rice straw by urea and calcium hydroxide on rumen ecology, microbial protein synthesis in beef cattle.

PubMed

Polyorach, S; Wanapat, M

2015-06-01

Four rumen-fistulated beef cattle were randomly assigned to four treatments according to a 4 × 4 Latin square design to study the influence of urea and calcium hydroxide [Ca(OH)2 ] treatment of rice straw to improve the nutritive value of rice straw. Four dietary treatments were as follows: untreated rice straw, 50 g/kg urea-treated rice straw, 20 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw and 30 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw. All animals were kept in individual pens and fed with concentrate at 0.5 g/kg of BW (DM), rice straw was fed ad libitum. The experiment was conducted for four periods, and each period lasted for 21 days. During the first 14 days, DM feed intake measurements were made while during the last 7 days, all cattle were moved to metabolism crates for total faeces and urine collections. The results revealed that 20 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw improved the nutritive value of rice straw, in terms of dry matter intake, digestibility, ruminal volatile fatty acids, population of bacteria and fungi, nitrogen retention and microbial protein synthesis. Based on this study, it could be concluded that using urea plus calcium hydroxide was one alternative method to improve the nutritive value of rice straw, rumen ecology and fermentation and thus a reduction of treatment cost. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

The mechanism of thermal-gradient mass transfer in the sodium hydroxide-nickel system

NASA Technical Reports Server (NTRS)

May, Charles E

1958-01-01

"Thermal-gradient mass transfer" was investigated in the molten sodium hydroxide-nickel system. Possible mechanisms (physical, electrochemical, and chemical) are discussed in terms of experimental and theoretical evidence. Experimental details are included in appendixes.

Ammonia induced precipitation of cobalt hydroxide: observation of turbostratic disorder

NASA Astrophysics Data System (ADS)

Ramesh, T. N.; Rajamathi, Michael; Kamath, P. Vishnu

2003-05-01

Cobalt hydroxide freshly precipitated from aqueous solutions of Co salts using ammonia, is a layered phase having a 9.17 Å interlayer spacing. DIFFaX simulations of the PXRD pattern reveal that it is turbostratically disordered.

Electrodeposited inorganic separators for alkaline batteries

NASA Technical Reports Server (NTRS)

Carson, W. N., Jr.; Consiglio, J. A.; Mc Quade, J. M.

1970-01-01

Coating electrodes of silver-cadmium cells with thermostable electrodeposits of calcium hydroxide or magnesium hydroxide reduces silver migration and increases cell life. Absence of organic matter enables assembled cells to be sterilized without oxidation of the material of the separators.

Arsenic Mobilization Influenced By Iron Reduction And Sulfidogenesis Under Dynamic Flow

NASA Astrophysics Data System (ADS)

Kocar, B. D.; Stewart, B. D.; Herbel, M.; Fendorf, S.

2004-12-01

Sulfidogenesis and iron reduction are ubiquitous processes that occur in a variety of anoxic subsurface and surface environments, which profoundly impact the cycling of arsenic. Of the iron (hydr)oxides, ferrihydrite possesses one of the highest capacities to retain arsenic, and is globally distributed within soils and sediments. Upon dissimilatory iron reduction, ferrihydrite may transform to lower surface area minerals, such as goethite and magnetite, which decreases arsenic retention, thus enhancing its transport. Here we examine how arsenic retained on ferrihydrite is mobilized under dynamic flow in the presence of Sulfurosprillum barnesii strain SES-3, a bacteria capable of reducing both As(V) and Fe(III). Ferrihydrite coated sands, loaded with 150 mg kg-1 As(V), were inoculated with S. barnesii, packed into a column and reacted with a synthetic groundwater solution. Within several days after initiation of flow, the concentration of arsenic in the column effluent increased dramatically coincident with the mineralogical transformation of ferrihydrite and As(V) reduction to As(III). Following the initial pulse of arsenic, effluent concentration then declined to less than 10 μ M. Thus, arsenic release into the aqueous phase is contingent upon the incongruent reduction of As(V) and Fe(III) as mediated by biological activity. Reaction of abiotically or biotically generated dissolved sulfide with iron (hydr)oxides may have a dramatic influence on the fate of arsenic within surface and subsurface environments. Accordingly, we examined the reaction of dissolved bisulfide and iron (hydr)oxide complexed with arsenic in both batch and column systems. Low ratios of sulfide to iron in batch reaction systems result in the formation of elemental sulfur and concomitant arsenic release from the iron (hydr)oxide surface. High sulfide to iron ratios, in contrast, appear to favor the formation of iron and arsenic sulfides. Our findings demonstrate that iron (hydr)oxides may quench reactions between sulfide and constituents sorbed to iron (hydr)oxide surfaces, forming elemental sulfur as opposed to sulfide-arsenic complexes. In addition, reductive transformation of iron (hydr)oxide by dissolved sulfide may release sorbed constituents. Hence, moderate to low concentrations of dissolved sulfide in association with iron (hydr)oxides may inhibit sequestration of important contaminants that are attenuated by Fe(III) and/or S(-II) bearing phases.

METHOD FOR RECOVERING PLUTONIUM VALUES FROM SOLUTION USING A BISMUTH HYDROXIDE CARRIER PRECIPITATE

DOEpatents

Faris, B.F.

1961-04-25

Carrier precipitation processes for separating plutonium values from aqueous solutions are described. In accordance with the invention a bismuth hydroxide precipitate is formed in the plutonium-containing solution, thereby carrying plutonium values from the solution.

Method and apparatus for regenerating cold traps within liquid-metal systems

DOEpatents

McKee, Jr., John M.

1976-01-01

Oxide and hydride impurities of a liquid metal such as sodium are removed from a cold trap by heating to a temperature at which the metal hydroxide is stable in a molten state. The partial pressure of hydrogen within the system is measured to determine if excess hydride or oxide is present. Excess hydride is removed by venting hydrogen gas while excess oxide can be converted to molten hydroxide through the addition of hydrogen. The resulting, molten hydroxide is drained from the trap which is then returned to service at cold trap temperatures within the liquid-metal system.

An improved method for analysis of hydroxide and carbonate in alkaline electrolytes containing zinc

NASA Technical Reports Server (NTRS)

Reid, M. A.

1978-01-01

A simplified method for titration of carbonate and hydroxide in alkaline battery electrolyte is presented involving a saturated KSCN solution as a complexing agent for zinc. Both hydroxide and carbonate can be determined in one titration, and the complexing reagent is readily prepared. Since the pH at the end point is shifted from 8.3 to 7.9-8.0, m-cresol purple or phenol red are used as indicators rather than phenolphthalein. Bromcresol green is recommended for determination of the second end point of a pH of 4.3 to 4.4.

An improved method for analysis of hydroxide and carbonate in alkaline electrolytes containing zinc

NASA Technical Reports Server (NTRS)

Reid, M. A.

1978-01-01

A simplified method for titration of carbonate and hydroxide in alkaline battery electrolyte is presented involving a saturated KSCN solution as a complexing agent for zinc. Both hydroxide and carbonate can be determined in one titration, and the complexing reagent is readily prepared. Since the pH at the end point is shifted from 8.3 to 7.9 - 8.0, m-cresol purple or phenol red are used as indicators rather than phenolphthalein. Bromcresol green is recommended for determination of the second end point of a pH of 4.3 to 4.4.

Development of Drug Delivery Systems Based on Layered Hydroxides for Nanomedicine

PubMed Central

Barahuie, Farahnaz; Hussein, Mohd Zobir; Fakurazi, Sharida; Zainal, Zulkarnain

2014-01-01

Layered hydroxides (LHs) have recently fascinated researchers due to their wide application in various fields. These inorganic nanoparticles, with excellent features as nanocarriers in drug delivery systems, have the potential to play an important role in healthcare. Owing to their outstanding ion-exchange capacity, many organic pharmaceutical drugs have been intercalated into the interlayer galleries of LHs and, consequently, novel nanodrugs or smart drugs may revolutionize in the treatment of diseases. Layered hydroxides, as green nanoreservoirs with sustained drug release and cell targeting properties hold great promise of improving health and prolonging life. PMID:24802876

Binder enhanced refuse derived fuel

DOEpatents

Daugherty, Kenneth E.; Venables, Barney J.; Ohlsson, Oscar O.

1996-01-01

A refuse derived fuel (RDF) pellet having about 11% or more particulate calcium hydroxide which is utilized in a combustionable mixture. The pellets are used in a particulate fuel bring a mixture of 10% or more, on a heat equivalent basis, of the RDF pellet which contains calcium hydroxide as a binder, with 50% or more, on a heat equivalent basis, of a sulphur containing coal. Combustion of the mixture is effective to produce an effluent gas from the combustion zone having a reduced SO.sub.2 and polycyclic aromatic hydrocarbon content of effluent gas from similar combustion materials not containing the calcium hydroxide.

Electrocatalysis and electroanalysis of nickel, its oxides, hydroxides and oxyhydroxides toward small molecules.

PubMed

Miao, Yuqing; Ouyang, Lei; Zhou, Shilin; Xu, Lina; Yang, Zhuoyuan; Xiao, Mingshu; Ouyang, Ruizhuo

2014-03-15

The electrocatalysis toward small molecules, especially small organic compounds, is of importance in a variety of areas. Nickel based materials such as nickel, its oxides, hydroxides as well as oxyhydroxides exhibit excellent electrocatalysis performances toward many small molecules, which are widely used for fuel cells, energy storage, organic synthesis, wastewater treatment, and electrochemical sensors for pharmaceutical, medical, food or environmental analysis. Their electrocatalytic mechanisms are proposed from three aspects such as Ni(OH)2/NiOOH mediated electrolysis, direct electrocatalysis of Ni(OH)2 or NiOOH. Under exposure to air or aqueous solution, two distinct layers form on the Ni surface with a Ni hydroxide layer at the air-oxide interface and an oxide layer between the metal substrate and the outer hydroxide layer. The transformation from nickel or its oxides to hydroxides or oxyhydroxides could be further speeded up in the strong alkaline solution under the cyclic scanning at relatively high positive potential. The redox transition between Ni(OH)2 and NiOOH is also contributed to the electrocatalytic oxidation of Ni and its oxides toward small molecules in alkaline media. In addition, nickel based materials or nanomaterials, their preparations and applications are also overviewed here. © 2013 Elsevier B.V. All rights reserved.

Controlling electrodeposited ultrathin amorphous Fe hydroxides film on V-doped nickel sulfide nanowires as efficient electrocatalyst for water oxidation

NASA Astrophysics Data System (ADS)

Shang, Xiao; Yan, Kai-Li; Lu, Shan-Shan; Dong, Bin; Gao, Wen-Kun; Chi, Jing-Qi; Liu, Zi-Zhang; Chai, Yong-Ming; Liu, Chen-Guang

2017-09-01

Developing cost-effective electrocatalysts with both high activity and stability remains challenging for oxygen evolution reaction (OER) in water electrolysis. Herein, based on V-doped nickel sulfide nanowire on nickel foam (NiVS/NF), we further conduct controllable electrodeposition of Fe hydroxides film on NiVS/NF (eFe/NiVS/NF) to further improve OER performance and stability. For comparison, ultrafast chemical deposition of Fe hydroxides on NiVS/NF (uFe/NiVS/NF) is also utilized. V-doping of NiVS/NF may introduce more active sites for OER, and nanowire structure can expose abundant active sites and facilitate mass transport. Both of the two depositions generate amorphous Fe hydroxides film covering on the surface of nanowires and lead to enhanced OER activities. Furthermore, electrodeposition strategy realizes uniform Fe hydroxides film on eFe/NiVS/NF confirmed by superior OER activity of eFe/NiVS/NF than uFe/NiVS/NF with relatively enhanced stability. The OER activity of eFe/NiVS/NF depends on various electrodepositon time, and the optimal time (15 s) is obtained with maximum OER activity. Therefore, the controllable electrodeposition of Fe may provide an efficient and simple strategy to enhance the OER properties of electrocatalysts.

Effect of Organic Cations on Hydrogen Oxidation Reaction of Carbon Supported Platinum

DOE PAGES

Chung, Hoon Taek; Choe, Yong-Kee; Martinez, Ulises; ...

2016-11-02

Effect of organic cations on hydrogen oxidation reaction (HOR) of carbon supported platinum (Pt/C) is investigated using three 0.1 M alkaline electrolytes, tetramethylammonium hydroxide (TMAOH), tetrabutylammonium hydroxide (TBAOH) and tetrabutylphosphonium hydroxide (TBPOH). Rotating disk electrode experiments indicate that the HOR of Pt/C is adversely impacted by time-dependent and potential-driven chemisorption of organic cations. In-situ infrared reflection adsorption spectroscopy experiments indicated that the specific chemisorption of organic cations drives the hydroxide co-adsorption on Pt surface. The co-adsorption of TMA + and hydroxide at 0.1 V vs. reversible hydrogen electrode is the strongest; consequently, complete removal of the co-adsorbed layer from Ptmore » surface is difficult even after exposure the Pt surface to 1.2 V. Conversely, the chemisorption of TBP+ is the weakest, yet notable decrease of HOR current density is still observed. The adsorption energies, ΔE, for TMA +, TBA +, and TBP + on Pt (111) surface from density functional theory are computed to be -2.79, -2.42 and -2.00 eV, respectively. The relatively low adsorption energy of TBP + is explained by the steric hindrance and electronic effect. This study emphasizes the importance of cationic group on HOR activity of alkaline anion exchange membrane fuel cells.« less

Hydroxide ion-mediated synthesis of monodisperse dopamine-melanin nanospheres.

PubMed

Cho, Soojeong; Kim, Shin-Hyun

2015-11-15

Dopamine-melanin nanospheres are promising materials for photoprotection, structural coloration, and thermoregulation due to their unusual optical and chemical properties. Here, we report the experimental parameters which influence size of dopamine-melanin nanospheres and uniformity. Dopamine precursors are oxidatively polymerized in basic aqueous medium. Therefore, concentration of hydroxide ions significantly influences reaction rate and size of nanospheres. To investigate the effect of hydroxide ions, we adjust three different parameters which affect pH of medium: concentration of sodium hydroxide and dopamine hydrochloride, and reaction temperature. At constant temperature, concentration of hydroxide ions is linearly proportional to initial reaction rates which determine the number of nuclei for nanosphere growth. Temperature alters not only initial reaction rate but also diffusivity of molecules, leading to deviation from the relation between the reaction rate and the number of nuclei. The diameter of dopamine-melanin nanospheres can be readily controlled in a range of 80-490nm through adjusting concentration of dopamine precursor, while maintaining uniform-size distribution and dispersion stability. The synthesized nanospheres are analyzed to confirm the chemical structure, which is composed of approximately 6 indole units. Moreover, surface and chemical properties of the nanospheres are characterized to provide valuable information for surface modification and application. Copyright © 2015 Elsevier Inc. All rights reserved.

Enhanced tortuosity for electrolytes in microwave irradiated self-organized carbon-doped Ni/Co hydroxide nanocomposite electrodes with higher Ni/Co atomic ratio and rate capability for an asymmetric supercapacitor

NASA Astrophysics Data System (ADS)

Kumar, Niraj; Kumar, Viresh; Panda, H. S.

2017-11-01

We demonstrate a green, facile and rapid microwave-mediated process for fabricating carbon black (CB) incorporated Ni/Co hydroxide porous nanocomposites and study the effect of various mass loading of CB on supercapacitor performance. The structure and interactions between CB and Ni/Co hydroxide are characterized by using x-ray diffraction, Fourier-transform infrared spectroscopy and x-ray photoelectron spectroscopy, which suggest the miniaturization of the single-phase Ni/Co hydroxide formation time. A morphology study reveals that the addition of CB into Ni/Co hydroxide develops a loose network structure with well-defined architectural pores. In addition, the nanocomposites demonstrate noticeable improvements in porosity and atomic ratio of Ni/Co with an increasing percentage of carbon, which results in a higher diffusion of electrolytes, and hence electrical conduction. The developed electrode materials exhibit a maximum specific capacitance value of 1526 Fg-1 at current density 1 Ag-1 with excellent cyclic stability (92% retention at 5000 cycles), energy density (76 Wh Kg-1), power density (250 W Kg-1) and rate capability. A solid state asymmetric supercapacitor device is fabricated and utilized to brighten a commercial LED effectively for validating real usage.

Enhanced tortuosity for electrolytes in microwave irradiated self-organized carbon-doped Ni/Co hydroxide nanocomposite electrodes with higher Ni/Co atomic ratio and rate capability for an asymmetric supercapacitor.

PubMed

Kumar, Niraj; Kumar, Viresh; Panda, H S

2017-11-03

We demonstrate a green, facile and rapid microwave-mediated process for fabricating carbon black (CB) incorporated Ni/Co hydroxide porous nanocomposites and study the effect of various mass loading of CB on supercapacitor performance. The structure and interactions between CB and Ni/Co hydroxide are characterized by using x-ray diffraction, Fourier-transform infrared spectroscopy and x-ray photoelectron spectroscopy, which suggest the miniaturization of the single-phase Ni/Co hydroxide formation time. A morphology study reveals that the addition of CB into Ni/Co hydroxide develops a loose network structure with well-defined architectural pores. In addition, the nanocomposites demonstrate noticeable improvements in porosity and atomic ratio of Ni/Co with an increasing percentage of carbon, which results in a higher diffusion of electrolytes, and hence electrical conduction. The developed electrode materials exhibit a maximum specific capacitance value of 1526 Fg -1 at current density 1 Ag -1 with excellent cyclic stability (92% retention at 5000 cycles), energy density (76 Wh Kg -1 ), power density (250 W Kg -1 ) and rate capability. A solid state asymmetric supercapacitor device is fabricated and utilized to brighten a commercial LED effectively for validating real usage.

Plasma graft-polymerization for synthesis of highly stable hydroxide exchange membrane

NASA Astrophysics Data System (ADS)

Hu, Jue; Zhang, Chengxu; Jiang, Lin; Fang, Shidong; Zhang, Xiaodong; Wang, Xiangke; Meng, Yuedong

2014-02-01

A novel plasma graft-polymerization approach is adopted to prepare hydroxide exchange membranes (HEMs) using cardo polyetherketone powders (PEK-C) and vinylbenzyl chloride. The benzylic chloromethyl groups can be successfully introduced into the PEK-C polymer matrix via plasma graft-polymerization. This approach enables a well preservation in the structure of functional groups and formation of a highly cross-linked structure in the membrane, leading to an improvement on the stability and performance of HEMs. The chemical stabilities, including alkaline and oxidative stability, are evaluated under severe conditions by measuring hydroxide conductivity and weight changes during aging. The obtained PGP-NOH membrane retains 86% of the initial hydroxide conductivity in 6 mol L-1 KOH solution at 60 °C for 120 h, and 94% of the initial weight in 3 wt% H2O2 solution at 60 °C for 262 h. The PGP-NOH membrane also possesses excellent thermal stability (safely used below 120 °C), alcohol resistance (ethanol permeability of 6.6 × 10-11 m2 s-1 and diffusion coefficient of 3.7 × 10-13 m2 s-1), and an acceptable hydroxide conductivity (8.3 mS cm-1 at 20 °C in deionized water), suggesting a good candidate of PGP-NOH membrane for HEMFC applications.

Alkaline hydrolysis of ethylene phosphate: an ab initio study by supermolecule model and polarizable continuum approach.

PubMed

Xia, Futing; Zhu, Hua

2011-09-01

The alkaline hydrolysis reaction of ethylene phosphate (EP) has been investigated using a supermolecule model, in which several explicit water molecules are included. The structures and single-point energies for all of the stationary points are calculated in the gas phase and in solution at the B3LYP/6-31++G(df,p) and MP2/6-311++G(df,2p) levels. The effect of water bulk solvent is introduced by the polarizable continuum model (PCM). Water attack and hydroxide attack pathways are taken into account for the alkaline hydrolysis of EP. An associative mechanism is observed for both of the two pathways with a kinetically insignificant intermediate. The water attack pathway involves a water molecule attacking and a proton transfer from the attacking water to the hydroxide in the first step, followed by an endocyclic bond cleavage to the leaving group. While in the first step of the hydroxide attack pathway the nucleophile is the hydroxide anion. The calculated barriers in aqueous solution for the water attack and hydroxide attack pathways are all about 22 kcal/mol. The excellent agreement between the calculated and observed values demonstrates that both of the two pathways are possible for the alkaline hydrolysis of EP. Copyright © 2011 Wiley Periodicals, Inc.

Phillips and Acaba with Lithium Hydroxide (LiOH) canisters on Middeck (MDDK)

NASA Image and Video Library

2009-03-19

S119-E-006645 (19 March 2009) --- Astronauts John Phillips (left) and Joseph Acaba, both STS-119 mission specialists, work with the lithium hydroxide (LiOH) canisters beneath Space Shuttle Discovery's middeck while docked with the International Space Station.

Consumption of Base by Glassware.

ERIC Educational Resources Information Center

Smith, Allen A.

1986-01-01

Discusses effects of Kimax and Pyrex glass on: (1) 0.4956 molar (M) ethanolic potassium hydroxide; (2) 0.1116 M aqueous sodium Hydroxide (NaOH); (3) 0.01081 M aqueous NaOH; (4) 0.001148 M aqueous NaOH; and on (5) distilled water. (JN)

PHYSICAL SOLUTIONS FOR ACID MINE DRAINAGE AT REMOTE MINE SITES

EPA Science Inventory

After completing extensive bench-scale testing to determine optimum treatment approaches, the technology has been taken to the field. Preliminary results show that calcium hydroxide precipitates the bulk of the arsenic and zinc; the granular ferric hydroxide removes the rest of ...

Synthesis, structure refinement and chromate sorption characteristics of an Al-rich bayerite-based layered double hydroxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Britto, Sylvia, E-mail: sylviabritto11@gmail.com; Kamath, P. Vishnu

2014-07-01

“Imbibition” of Zn{sup 2+} ions into the cation vacancies of bayerite–Al(OH){sub 3} and NO{sub 3}{sup −} ions into the interlayer gallery yields an Al-rich layered double hydroxide with Al/Zn ratio ∼3. NO{sub 3}{sup −} ions are intercalated with their molecular planes inclined at an angle to the plane of the metal hydroxide slab and bonded to it by hydrogen bonds. Rietveld refinement of the structure shows that the monoclinic symmetry of the precursor bayerite is preserved in the product, showing that the imbibition is topochemical in nature. The nitrate ion is labile and is quantitatively replaced by CrO{sub 4}{sup 2−}more » ions from solution. The uptake of CrO{sub 4}{sup 2−} ions follows a Langmuir adsorption isotherm, thus showing that the hydroxide is a candidate material for green chemistry applications for the removal of CrO{sub 4}{sup 2−} ions from waste water. Rietveld refinement of the structure of the hydroxide after CrO{sub 4}{sup 2−} inclusion reveals that the CrO{sub 4}{sup 2−} ion is intercalated with one of its 2-fold axes parallel to the b-crystallographic axis of the crystal, also the principal 2 axis of the monoclinic cell. - Graphical abstract: The structure of the [Zn–Al4-nitrate] LDH viewed along the a-axis. - Highlights: • Synthesis of Al-rich layered double hydroxide with Al/Zn ratio ∼3. • Rietveld refinement indicates that the imbibition of Zn into Al(OH){sub 3} is topochemical in nature. • The uptake of CrO{sub 4}{sup 2−} ions follows a Langmuir adsorption isotherm.« less

Aluminum affects heterogeneous Fe(III) (Hydr)oxide nucleation, growth, and ostwald ripening.

PubMed

Hu, Yandi; Li, Qingyun; Lee, Byeongdu; Jun, Young-Shin

2014-01-01

Heterogeneous coprecipitation of iron and aluminum oxides is an important process for pollutant immobilization and removal in natural and engineered aqueous environments. Here, using a synchrotron-based small-angle X-ray scattering technique, we studied heterogeneous nucleation and growth of Fe(III) (hydr)oxide on quartz under conditions found in acid mine drainage (at pH = 3.7 ± 0.2, [Fe(3+)] = 10(-4) M) with different initial aqueous Al/Fe ratios (0:1, 1:1, and 5:1). Interestingly, although the atomic ratios of Al/Fe in the newly formed Fe(III) (hydr)oxide precipitates were less than 1%, the in situ particle size and volume evolutions of the precipitates on quartz were significantly influenced by aqueous Al/Fe ratios. At the end of the 3 h experiments, with aqueous Al/Fe ratios of 0:1, 1:1, and 5:1, the average radii of gyration of particles on quartz were 5.7 ± 0.3, 4.6 ± 0.1, and 3.7 ± 0.3 nm, respectively, and the ratio of total particle volumes on quartz was 1.7:3.4:1.0. The Fe(III) (hydr)oxide precipitates were poorly crystallized, and were positively charged in all solutions. In the presence of Al(3+), Al(3+) adsorption onto quartz changed the surface charge of quartz from negative to positive, which caused the slower heterogeneous growth of Fe(III) (hydr)oxide on quartz. Furthermore, Al affected the amount of water included in the Fe(III) (hydr)oxides, which can influence their adsorption capacity. This study yielded important information usable for pollutant removal not only in natural environments, but also in engineered water treatment processes.

A case study for removal of sulphur-di-oxide from exhaust flue gases at thermal power plant, Rajasthan (India).

PubMed

Sharma, Rashmi; Acharya, Shveta; Sharma, Arun Kumar

2011-01-01

The aim of this study is to reduce the percent SO2 in environment and to produce a byproduct with SO2, to control air pollution. The present work envisages a situation that compares the efficiency of three different reagents, viz. sodium hydroxide, calcium hydroxide and waste product of water treatment plant containing CaO in removal of SO2 that would be generated in this situation. Various parameters were also observed with variation involving percent concentration of reactants, pH of the solution, time for reaction , temperature of solution and flow of flue gas in impingers. Pet coke with lime stone is being used for power generation in power plant during the experiment, the pet coke having 6% sulphur resulting in emission of SO2. Hence experiments have been conducted to trap these gases to produce sulphates. Waste product of water treatment plant, calcium hydroxide, and sodium hydroxide in various permutation and combination have been used with control flow by SO2 monitoring kit for preparation of calcium sulphate and sodium sulphate. Thus sodium hydroxide turned out to be better as compared to calcium hydroxide and sludge. It is also concluded that pH of the solution should be alkaline for good absorption of SO2 and maximum absorption of SO2 found in direct passing of SO2 in impinger as compared to indirect passing of SO2 in impingers. Good absorption of SO2 found at temperature range between 20-25 degrees C and it seems to be optimum. Maximum recovery of SO2 was obtained when the reaction took place for long time period.

Beyond-use dating of lidocaine alone and in two "magic mouthwash" preparations.

PubMed

Kirk, Loren Madden; Brown, Stacy D; Luu, Yao; Ogle, Amanda; Huffman, Jessica; Lewis, Paul O

2017-05-01

Beyond-use dating (BUD) of lidocaine alone and in two "magic mouthwash" preparations stored in amber oral syringes at room temperature was determined. Two formulations of mouthwash containing oral topical lidocaine 2% (viscous), diphenhydramine 2.5 mg/mL, and aluminum hydroxide-magnesium hydroxide-simethicone were prepared in 1:1:1 and 1:2.5:2.5 ratios, divided into 3-mL samples, and stored in unit-dose oral amber syringes. Unit-dose single-product lidocaine samples were also prepared to serve as controls and stored in oral amber syringes. The lidocaine concentrations in these samples were measured periodically for 90 days. A stability-indicating high-performance liquid chromatographic method was developed and validated for system suitability, accuracy, repeatability, intermediate precision, specificity, linearity, and robustness. Based on the calculated percentages versus the initial concentration and the results from an analysis of variance comparing the two formulations, a BUD of 21 days is deemed appropriate for both magic mouthwash formulations. Based on the stability data, published safety concerns, and lack of efficacy in combination, packaging and dispensing lidocaine separately from other ingredients are recommended when administering magic mouthwash mixtures. Utilizing a 90-day BUD, lidocaine can be packaged separately from other magic mouthwash ingredients in individual dosage units and applied to the oral cavity using the swish-and-spit method. The delivery of the diphenhydramine and aluminum hydroxide-magnesium hydroxide-simethicone could be separated, allowing for a swish-and-swallow method of administration. A BUD of 21 days is recommended for lidocaine prepared with diphenhydramine and aluminum hydroxide-magnesium hydroxide-simethicone in ratios of 1:1:1 and 1:2.5:2.5 and stored at room temperature in amber oral plastic syringes. Copyright © 2017 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Ionic substitution of Mg2+ for Al3+ and Fe3+ with octahedral coordination in hydroxides facilitate precipitation of layered double hydroxides

NASA Astrophysics Data System (ADS)

Paikaray, Susanta; Essilfie-Dughan, Joseph; Hendry, M. Jim

2018-01-01

Precipitation of hydrotalcite-like layered double hydroxides (HT-LDHs) from CO32--SO42--rich acidic and alkaline aqueous media through ionic substitution of Mg2+ for Al3+ + Fe3+ and vice versa was investigated under ambient conditions. Diffractogram, spectroscopic, microprobe, microscopic, and synchrotron techniques were used to examine the mechanisms involved. The cations facilitated rapid precipitation of HT-LDH in alkaline conditions (pH ≥ 8.2) with SO42- and CO32- as the counter charge balancing interlayer anions, while initial formation of Fe3+- and Al3+-hydroxides in acidic conditions (pH ≥ 2.4) with subsequent transformation to MgAlFe-type HT-LDH (pH ≥ 8.2) occurred through substitution of Mg2+ for Al3+ and Fe3+. Substitution of Al3+ and Fe3+ in Mg2+-hydroxides did not yield HT-LDH, while the reverse, i.e., Mg2+ substitution in Al3+ and Fe3+-hydroxides, produced initial poorly ordered amorphous HT-LDH that gained better crystallinity and crystallite size upon neutralization. Linear combination fit analyses of XANES data suggest schwertmannite constituted the predominant Fe-phase until pH ∼3.7 followed by ferrihydrite and eventually HT-LDH after pH ≥ 10; basaluminite and epsomite constituted the predominant Al and Mg phases until pH ∼4.5, after which HT-LDH with minor Al(OH)3 and HT-LDH with brucite, respectively, predominated. The study highlights that Mg2+ substitution in Al- and Fe-precipitates is the governing mechanism for HT-LDH precipitation in oxic environments through neutralization of acidic cationic aqueous residues.

REMOVAL OF CESIUM BY SORPTION FROM AQUEOUS SOLUTIONS

DOEpatents

Ames, L.L.

1962-01-16

ABS>A process is given for selectively removing cesium from acid aqueous solutions containing cesium in microquantities and other cations in macroquantities by absorption on clinoptilolite. The cesium can be eluted from the clinoptilolite with a solution of ammonia, potassium hydroxide, or rubidium hydroxide. (AEC)

Forced-convection Heat-transfer Characteristics of Molten Sodium Hydroxide

NASA Technical Reports Server (NTRS)

Grele, Milton D; Gedeon, Louis

1953-01-01

The forced-convection heat-transfer characteristics of sodium hydroxide were experimentally investigated. The heat-transfer data for heating fall slightly above the McAdams correlation line, and the heat-transfer data for cooling are fairly well represented by the McAdams correlation line.

LIGNOSULFONATE-MODIFIED CALCIUM HYDROXIDE FOR SULFUR DIOXIDE CONTROL

EPA Science Inventory

The article discusses the use of lignosulfonate-modified calcium hydroxide Ca(OH)2 for sulfur dioxide (SO2) control. The limestone injection multistage burner (LIMB) process is currently being developed at the U.S. EPA as a low cost retrofittable technology for controlling oxides...

Titration of Monoprotic Acids with Sodium Hydroxide Contaminated by Sodium Carbonate.

ERIC Educational Resources Information Center

Michalowski, Tadeusz

1988-01-01

Discusses the effects of using carbon dioxide contaminated sodium hydroxide solution as a titrant for a solution of a weak monoprotic acid and the resulting distortion of the titration curve in comparison to one obtained when an uncontaminated titrant is used. (CW)

40 CFR 61.51 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... produce chlorine gas, hydrogen gas, and alkali metal hydroxide. (f) Mercury chlor-alkali electrolyzer... converted to alkali metal hydroxide, mercury, and hydrogen gas in a short-circuited, electrolytic reaction. (h) Hydrogen gas stream means a hydrogen stream formed in the chlor-alkali cell denuder. (i) End box...

40 CFR 61.51 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... produce chlorine gas, hydrogen gas, and alkali metal hydroxide. (f) Mercury chlor-alkali electrolyzer... converted to alkali metal hydroxide, mercury, and hydrogen gas in a short-circuited, electrolytic reaction. (h) Hydrogen gas stream means a hydrogen stream formed in the chlor-alkali cell denuder. (i) End box...

40 CFR 61.51 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... produce chlorine gas, hydrogen gas, and alkali metal hydroxide. (f) Mercury chlor-alkali electrolyzer... converted to alkali metal hydroxide, mercury, and hydrogen gas in a short-circuited, electrolytic reaction. (h) Hydrogen gas stream means a hydrogen stream formed in the chlor-alkali cell denuder. (i) End box...

40 CFR 61.51 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... produce chlorine gas, hydrogen gas, and alkali metal hydroxide. (f) Mercury chlor-alkali electrolyzer... converted to alkali metal hydroxide, mercury, and hydrogen gas in a short-circuited, electrolytic reaction. (h) Hydrogen gas stream means a hydrogen stream formed in the chlor-alkali cell denuder. (i) End box...

40 CFR 61.51 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... produce chlorine gas, hydrogen gas, and alkali metal hydroxide. (f) Mercury chlor-alkali electrolyzer... converted to alkali metal hydroxide, mercury, and hydrogen gas in a short-circuited, electrolytic reaction. (h) Hydrogen gas stream means a hydrogen stream formed in the chlor-alkali cell denuder. (i) End box...

Tanner and Burbank store lithium hydroxide canisters beneath the MDDK during Expedition 13 / STS-115 Joint Operations

NASA Image and Video Library

2006-09-16

S115-E-06528 (9-21 Sept. 2006) --- Astronauts Joseph R. Tanner (left) and Daniel C. Burbank, both STS-115 mission specialists, work with the lithium hydroxide (LiOH) canisters beneath Space Shuttle Atlantis' middeck.

Astronauts Newman, Walz and Bursch change out lithium hydroxide canister

NASA Image and Video Library

1993-09-20

STS051-08-037 (12-22 Sept 1993) --- Three members of the astronaut class of 1990 change out a lithium hydroxide canister beneath Discovery's middeck. Left to right are astronauts James H. Newman, Carl E. Walz and Daniel W. Bursch, all mission specialists.

PHYSICAL SOLUTIONS FOR ACID MINE DRAINAGE AT REMOTE MINE SITES (SLIDES)

EPA Science Inventory

After completing extensive bench-scale testing to determine optimum treatment approaches, the technology has been taken to the field. Preliminary results show that calcium hydroxide precipitates the bulk of the arsenic and zinc; the granular ferric hydroxide removes the rest of ...

Study of dynamics of glucose-glucose oxidase-ferricyanide reaction

NASA Astrophysics Data System (ADS)

Nováková, A.; Schreiberová, L.; Schreiber, I.

2011-12-01

This work is focused on dynamics of the glucose-glucose oxidase-ferricyanide enzymatic reaction with or without sodium hydroxide in a continuous-flow stirred tank reactor (CSTR) and in a batch reactor. This reaction exhibits pH-variations having autocatalytic character and is reported to provide nonlinear dynamic behavior (bistability, excitability). The dynamical behavior of the reaction was examined within a wide range of inlet parameters. The main inlet parameters were the ratio of concentrations of sodium hydroxide and ferricyanide and the flow rate. In a batch reactor we observed an autocatalytic drop of pH from slightly basic to medium acidic values. In a CSTR our aim was to find bistability in the presence of sodium hydroxide. However, only a basic steady state was found. In order to reach an acidic steady state, we investigated the system in the absence of sodium hydroxide. Under these conditions the transition from the basic to the acidic steady state was observed when inlet glucose concentration was increased.

An empirical model to estimate density of sodium hydroxide solution: An activator of geopolymer concretes

NASA Astrophysics Data System (ADS)

Rajamane, N. P.; Nataraja, M. C.; Jeyalakshmi, R.; Nithiyanantham, S.

2016-02-01

Geopolymer concrete is zero-Portland cement concrete containing alumino-silicate based inorganic polymer as binder. The polymer is obtained by chemical activation of alumina and silica bearing materials, blast furnace slag by highly alkaline solutions such as hydroxide and silicates of alkali metals. Sodium hydroxide solutions of different concentrations are commonly used in making GPC mixes. Often, it is seen that sodium hydroxide solution of very high concentration is diluted with water to obtain SHS of desired concentration. While doing so it was observed that the solute particles of NaOH in SHS tend to occupy lower volumes as the degree of dilution increases. This aspect is discussed in this paper. The observed phenomenon needs to be understood while formulating the GPC mixes since this influences considerably the relationship between concentration and density of SHS. This paper suggests an empirical formula to relate density of SHS directly to concentration expressed by w/w.

Alternative alkaline conditioning of amidoxime based adsorbent for uranium extraction from seawater

DOE PAGES

Das, Sadananda; Liao, Wei -Po; Byers, Maggie Flicker; ...

2015-10-18

Alkaline conditioning of the amidoxime based adsorbents is a significant step in the preparation of the adsorbent for uranium uptake from seawater. The effects of various alkaline conditioning parameters such as the type of alkaline reagent, reaction temperature, and reaction time were investigated with respect to uranium adsorption capacity from simulated seawater (spiked with 8 ppm uranium) and natural seawater (from Sequim Bay, WA). An adsorbent (AF1) was prepared at the Oak Ridge National Laboratory by radiation-induced graft polymerization (RIGP) with acrylonitrile and itaconic acid onto high-surface-area polyethylene fibers. For the AF1 adsorbent, sodium hydroxide emerged as a better reagentmore » for alkaline conditioning over potassium hydroxide, which has typically been used in previous studies, because of higher uranium uptake capacity and lower cost over the other candidate alkaline reagents investigated in this study. Furthermore, the use of sodium hydroxide in place of potassium hydroxide is shown to result in a 21–30% decrease in the cost of uranium recovery.« less

A surface-enhanced infrared absorption spectroscopic study of pH dependent water adsorption on Au

NASA Astrophysics Data System (ADS)

Dunwell, Marco; Yan, Yushan; Xu, Bingjun

2016-08-01

The potential dependent behavior of near-surface water on Au film electrodes in acidic and alkaline solutions is studied using a combination of attenuated total reflectance surface enhanced infrared spectroscopy and chronoamperometry. In acid, sharp νOH peaks appear at 3583 cm- 1 at high potentials attributed to non-H-bonded water coadsorbed in the hydration sphere of perchlorate near the electrode surface. Adsorbed hydronium bending mode at near 1680 cm- 1 is observed at low potentials in low pH solutions (1.4, 4.0, 6.8). At high pH (10.0, 12.3), a potential-dependent OH stretching band assigned to adsorbed hydroxide emerges from 3400-3506 cm- 1. The observation of adsorbed hydroxide, even on a weakly oxophilic metal such as Au, provides the framework for further studies of hydroxide adsorption on other electrodes to determine the role of adsorbed hydroxide on important reactions such as the hydrogen oxidation reaction.

Effect of Coexisting Ions on Adsorption of Arsenic by Metal Oxides

NASA Astrophysics Data System (ADS)

Meng, Xiaoguang; Shi, Qiantao; Christodoulatos, Christos

2017-04-01

Iron hydroxides and nano TiO2 are commonly used adsorbents for removal of arsenic in water. Iron hydroxides also play an important role in controlling the fate and transport of arsenic in groundwater. Co-existing anions, such as phosphate, silicate, and bicarbonate could significantly affect the adsorption capacity of the adsorbents for arsenate and arsenite and increase their mobility in groundwater aquifers. Arsenate and arsenite interactions at the solid-water interface were investigated using electrophoretic mobility (EM) measurements, Fourier transform infrared (FTIR) spectroscopy, and extended X-ray absorption fine structure (EXAFS) spectroscopy. Electrochemical scanning tunneling microscopy (ECSTM) and in-situ flow cell ATR-FTIR were applied to investigate the interactions between As(III), As(V) and carbonate in water and at the solid-water interface. The experimental results suggested that arsenate and arsenite formed inner-sphere complexes with the hydroxide groups on the adsorbents. Arsenite and carbonate could form ternary surface complexes with the hydroxyl groups on iron hydroxide.

The effect of chemical treatment on reduction of aflatoxins and ochratoxin A in black and white pepper during washing.

PubMed

Jalili, M; Jinap, S; Son, R

2011-04-01

The effect of 18 different chemicals, which included acidic compounds (sulfuric acid, chloridric acid, phosphoric acid, benzoic acid, citric acid, acetic acid), alkaline compounds (ammonia, sodium bicarbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide), salts (acetate ammonium, sodium bisulfite, sodium hydrosulfite, sodium chloride, sodium sulfate) and oxidising agents (hydrogen peroxide, sodium hypochlorite), on the reduction of aflatoxins B(1), B(2), G(1) and G(2) and ochratoxin A (OTA) was investigated in black and white pepper. OTA and aflatoxins were determined using HPLC after immunoaffinity column clean-up. Almost all of the applied chemicals showed a significant degree of reduction on mycotoxins (p < 0.05). The lowest and highest reduction of aflatoxin B(1), which is the most dangerous aflatoxin, was 20.5% ± 2.7% using benzoic acid and 54.5% ± 2.7% using sodium hydroxide. There was no significant difference between black and white peppers (p < 0.05).

Toxicity and Metabolism of Layered Double Hydroxide Intercalated with Levodopa in a Parkinson’s Disease Model

PubMed Central

Kura, Aminu Umar; Ain, Nooraini Mohd; Hussein, Mohd Zobir; Fakurazi, Sharida; Hussein-Al-Ali, Samer Hasan

2014-01-01

Layered hydroxide nanoparticles are generally biocompatible, and less toxic than most inorganic nanoparticles, making them an acceptable alternative drug delivery system. Due to growing concern over animal welfare and the expense of in vivo experiments both the public and the government are interested to find alternatives to animal testing. The toxicity potential of zinc aluminum layered hydroxide (ZAL) nanocomposite containing anti-Parkinsonian agent may be determined using a PC 12 cell model. ZAL nanocomposite demonstrated a decreased cytotoxic effect when compared to levodopa on PC12 cells with more than 80% cell viability at 100 μg/mL compared to less than 20% cell viability in a direct levodopa exposure. Neither levodopa-loaded nanocomposite nor the un-intercalated nanocomposite disturbed the cytoskeletal structure of the neurogenic cells at their IC50 concentration. Levodopa metabolite (HVA) released from the nanocomposite demonstrated the slow sustained and controlled release character of layered hydroxide nanoparticles unlike the burst uptake and release system shown with pure levodopa treatment. PMID:24722565

A role for calcium hydroxide and dolomite in water: acceleration of the reaction under ultraviolet light.

PubMed

Nagase, Hiroyasu; Tsujino, Hidekazu; Kurihara, Daisuke; Saito, Hiroshi; Kawase, Masaya

2014-04-01

Organic environmental pollutants are now being detected with remarkably high frequency in the aquatic environment. Photodegradation by ultraviolet light is sometimes used as a method for removing organic chemicals from water; however, this method is relatively inefficient because of the low degradation rates involved, and more efficient methods are under development. Here we show that the removal of various organic pollutants can be assisted by calcined dolomite in aqueous solution under irradiation with ultraviolet light. It was possible to achieve substantial removal of bisphenol A, chlorophenols, alkylphenols, 1-naphthol and 17β-estradiol. The major component of dolomite responsible for the removal was calcium hydroxide. Our results demonstrate that the use of calcium hydroxide with ultraviolet light irradiation can be a very effective method of rapidly removing organic environmental pollutants from water. This is a new role for calcium hydroxide and dolomite in water treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Layered double hydroxide stability. 2. Formation of Cr(III)-containing layered double hydroxides directly from solution

NASA Technical Reports Server (NTRS)

Boclair, J. W.; Braterman, P. S.; Jiang, J.; Lou, S.; Yarberry, F.

1999-01-01

Solutions containing divalent metal [M(II) = Mg2+, Zn2+, Co2+, Ni2+, Mn2+] chlorides and CrCl3 6H2O were titrated with NaOH to yield, for M(II) = Zn, Co, and Ni, hydrotalcite-like layered double hydroxides (LDHs), [[M(II)]1-z[Cr(III)]z(OH)2][Cl]z yH2O, in a single step, without intermediate formation of chromium hydroxide. Analysis of the resultant titration curves yields solubility constants for these compounds. These are in the order Zn < Ni approximately Co, with a clear preference for formation of the phase with z = 1/3. With Mg2+ as chloride, titration gives a mixture of Cr(OH)3 and Mg(OH)2, but the metal sulfates give Mg2Cr(OH)6 1/2(SO4) by a two-step process. Titrimetric and spectroscopic evidence suggests short-range cation order in the one-step LDH systems.

Alternative Alkaline Conditioning of Amidoxime Based Adsorbent for Uranium Extraction from Seawater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Das, S.; Liao, W. -P.; Flicker Byers, M.

2016-04-20

Alkaline conditioning of the amidoxime based adsorbents is a significant step in the preparation of the adsorbent for uranium uptake from seawater. The effects of various alkaline conditioning parameters such as the type of alkaline reagent, reaction temperature, and reaction time were investigated with respect to uranium adsorption capacity from simulated seawater (spiked with 8 ppm uranium) and natural seawater (from Sequim Bay, WA). An adsorbent (AF1) was prepared at the Oak Ridge National Laboratory by radiation-induced graft polymerization (RIGP) with acrylonitrile and itaconic acid onto high-surface-area polyethylene fibers. For the AF1 adsorbent, sodium hydroxide emerged as a better reagentmore » for alkaline conditioning over potassium hydroxide, which has typically been used in previous studies, because of higher uranium uptake capacity and lower cost over the other candidate alkaline reagents investigated in this study. Use of sodium hydroxide in place of potassium hydroxide is shown to result in a 21-30% decrease in the cost of uranium recovery.« less

PROCESS OF RECOVERING URANIUM

DOEpatents

Kilner, S.B.

1959-12-29

A method is presented for separating and recovering uranium from a complex mixure of impurities. The uranium is dissolved to produce an aqueous acidic solution including various impurities. In accordance with one method, with the uranium in the uranyl state, hydrogen cyanide is introduced into the solution to complex the impurities. Subsequently, ammonia is added to the solution to precipitate the uraniunn as ammonium diuranate away from the impurities in the solution. Alternatively, the uranium is precipitated by adding an alkaline metal hydroxide. In accordance with the second method, the uranium is reduced to the uranous state in the solution. The reduced solution is then treated with solid alkali metal cyanide sufficient to render the solution about 0.1 to 1.0 N in cyanide ions whereat cyanide complex ions of the metal impurities are produced and the uranium is simultaneously precipituted as uranous hydroxide. Alternatively, hydrogen cyanide may be added to the reduced solution and the uranium precipitated subsequently by adding ammonium hydroxide or an alkali metal hydroxide. Other refinements of the method are also disclosed.

Chemical treatment of wastewater from flue gas desulphurisation

NASA Astrophysics Data System (ADS)

Pasiecznik, Iwona; Szczepaniak, Włodzimierz

2017-11-01

The article presents results of laboratory tests of removing boron and arsenium from non-ideal solutions using double-layered magnesium/aluminium hydroxides (Mg/Al Double-Layered Hydroxide - DLH) produced with nitrate-chloride method. In research, wastewater from an installation for flue gas desulfurization was examined. Double-layered hydroxides are perfect absorbents for anionic compounds. The research proved high effectiveness of preparation with reference to arsenium, as well as confirmed the effect of presence of sulfatic and arsenate ions on the effectiveness of boron removal. On the basis of research on absorption kinetics a theoretical dose of DLH/NO3-Cl/M preparation was calculated and compared with a dose that ensures emimination of boron below the limit standarized by the national regulations. Application of double-layered magnesium/aluminium hydroxides for boron elimination from industrial wastewater requires significantly higher doses of preparation than those calculated in model investigations. It is due to the priority of removal of multivalent ions, such as sulfatic, arsenate or phosphate ions, by DLH/NO3-Cl/M.

Encapsulation of sulfur with thin-layered nickel-based hydroxides for long-cyclic lithium–sulfur cells

PubMed Central

Jiang, Jian; Zhu, Jianhui; Ai, Wei; Wang, Xiuli; Wang, Yanlong; Zou, Chenji; Huang, Wei; Yu, Ting

2015-01-01

Elemental sulfur cathodes for lithium/sulfur cells are still in the stage of intensive research due to their unsatisfactory capacity retention and cyclability. The undesired capacity degradation upon cycling originates from gradual diffusion of lithium polysulfides out of the cathode region. To prevent losses of certain intermediate soluble species and extend lifespan of cells, the effective encapsulation of sulfur plays a critical role. Here we report an applicable way, by using thin-layered nickel-based hydroxide as a feasible and effective encapsulation material. In addition to being a durable physical barrier, such hydroxide thin films can irreversibly react with lithium to generate protective layers that combine good ionic permeability and abundant functional polar/hydrophilic groups, leading to drastic improvements in cell behaviours (almost 100% coulombic efficiency and negligible capacity decay within total 500 cycles). Our present encapsulation strategy and understanding of hydroxide working mechanisms may advance progress on the development of lithium/sulfur cells for practical use. PMID:26470847

Alternative alkaline conditioning of amidoxime based adsorbent for uranium extraction from seawater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Das, Sadananda; Liao, Wei -Po; Byers, Maggie Flicker

Alkaline conditioning of the amidoxime based adsorbents is a significant step in the preparation of the adsorbent for uranium uptake from seawater. The effects of various alkaline conditioning parameters such as the type of alkaline reagent, reaction temperature, and reaction time were investigated with respect to uranium adsorption capacity from simulated seawater (spiked with 8 ppm uranium) and natural seawater (from Sequim Bay, WA). An adsorbent (AF1) was prepared at the Oak Ridge National Laboratory by radiation-induced graft polymerization (RIGP) with acrylonitrile and itaconic acid onto high-surface-area polyethylene fibers. For the AF1 adsorbent, sodium hydroxide emerged as a better reagentmore » for alkaline conditioning over potassium hydroxide, which has typically been used in previous studies, because of higher uranium uptake capacity and lower cost over the other candidate alkaline reagents investigated in this study. Furthermore, the use of sodium hydroxide in place of potassium hydroxide is shown to result in a 21–30% decrease in the cost of uranium recovery.« less

Preparation and characterization of an anti-inflammatory agent based on a zinc-layered hydroxide-salicylate nanohybrid and its effect on viability of Vero-3 cells

PubMed Central

Ramli, Munirah; Hussein, Mohd Zobir; Yusoff, Khatijah

2013-01-01

A new organic-inorganic nanohybrid based on zinc-layered hydroxide intercalated with an anti-inflammatory agent was synthesized through direct reaction of salicylic acid at various concentrations with commercially available zinc oxide. The basal spacing of the pure phase nanohybrid was 15.73 Å, with the salicylate anions arranged in a monolayer form and an angle of 57 degrees between the zinc-layered hydroxide interlayers. Fourier transform infrared study further confirmed intercalation of salicylate into the interlayers of zinc-layered hydroxide. The loading of salicylate in the nanohybrid was estimated to be around 29.66%, and the nanohybrid exhibited the properties of a mesoporous-type material, with greatly enhanced thermal stability of the salicylate compared with its free counterpart. In vitro cytotoxicity assay revealed that free salicylic acid, pure zinc oxide, and the nanohybrid have a mild effect on viability of African green monkey kidney (Vero-3) cells. PMID:23345976

Electrochemical Formation of Multilayer SnO2-Sb x O y Coating in Complex Electrolyte

NASA Astrophysics Data System (ADS)

Maizelis, Antonina; Bairachniy, Boris

2017-02-01

The multilayer antimony-doped tin dioxide coating was obtained by cathodic deposition of multilayer metal-hydroxide coating with near 100-nm thickness layers on the alloy underlayer accompanied by the anodic oxidation of this coating. The potential regions of deposition of tin, antimony, tin-antimony alloy, and mixture of this metals and their hydroxides in the pyrophosphate-tartrate electrolyte were revealed by the cyclic voltammetric method. The possibility of oxidation of cathodic deposit consisting of tin and Sn(II) hydroxide compounds to the hydrated tin dioxide in the same electrolyte was demonstrated. The operations of alloy underlayer deposition and oxidation of multilayer metal-hydroxide coating were proposed to carry out in the diluted pyrophosphate-tartrate electrolyte, similar to the main electrolyte. The accelerated tests showed higher service life of the titanium electrode with multilayer antimony-doped tin dioxide coating compared to both electrode with single-layer electrodeposited coating and the electrode with the coating obtained using prolonged heat treatment step.

Electrochemical Formation of Multilayer SnO2-Sb x O y Coating in Complex Electrolyte.

PubMed

Maizelis, Antonina; Bairachniy, Boris

2017-12-01

The multilayer antimony-doped tin dioxide coating was obtained by cathodic deposition of multilayer metal-hydroxide coating with near 100-nm thickness layers on the alloy underlayer accompanied by the anodic oxidation of this coating. The potential regions of deposition of tin, antimony, tin-antimony alloy, and mixture of this metals and their hydroxides in the pyrophosphate-tartrate electrolyte were revealed by the cyclic voltammetric method. The possibility of oxidation of cathodic deposit consisting of tin and Sn(II) hydroxide compounds to the hydrated tin dioxide in the same electrolyte was demonstrated.The operations of alloy underlayer deposition and oxidation of multilayer metal-hydroxide coating were proposed to carry out in the diluted pyrophosphate-tartrate electrolyte, similar to the main electrolyte.The accelerated tests showed higher service life of the titanium electrode with multilayer antimony-doped tin dioxide coating compared to both electrode with single-layer electrodeposited coating and the electrode with the coating obtained using prolonged heat treatment step.

Chemically and compositionally modified solid solution disordered multiphase nickel hydroxide positive electrode for alkaline rechargeable electrochemical cells

DOEpatents

Ovshinsky, Stanford R.; Corrigan, Dennis; Venkatesan, Srini; Young, Rosa; Fierro, Christian; Fetcenko, Michael A.

1994-01-01

A high capacity, long cycle life positive electrode for use in an alkaline rechargeable electrochemical cell comprising: a solid solution nickel hydroxide material having a multiphase structure that comprises at least one polycrystalline .gamma.-phase including a polycrystalline .gamma.-phase unit cell comprising spacedly disposed plates with at least one chemical modifier incorporated around the plates, the plates having a range of stable intersheet distances corresponding to a 2.sup.+ oxidation state and a 3.5.sup.+, or greater, oxidation state; and at least one compositional modifier incorporated into the solid solution nickel hydroxide material to promote the multiphase structure.

Thermochemical generation of hydrogen and oxygen from water

DOEpatents

Robinson, Paul R.; Bamberger, Carlos E.

1981-01-01

A thermochemical cyclic process for the production of hydrogen exploits the reaction between sodium manganate (NaMnO.sub.2) and titanium dioxide (TiO.sub.2) to form sodium titanate (Na.sub.2 TiO.sub.3), manganese (II) titanate (MnTiO.sub.3) and oxygen. The titanate mixture is treated with sodium hydroxide, in the presence of steam, to form sodium titanate, sodium manganate (III), water and hydrogen. The sodium titanate-manganate (III) mixture is treated with water to form sodium manganate (III), titanium dioxide and sodium hydroxide. Sodium manganate (III) and titanium dioxide are recycled following dissolution of sodium hydroxide in water.

Thermochemical generation of hydrogen and oxygen from water

DOEpatents

Robinson, Paul R.; Bamberger, Carlos E.

1982-01-01

A thermochemical cyclic process for the production of hydrogen exploits the reaction between sodium manganate (NaMnO.sub.2) and titanium dioxide (TiO.sub.2) to form sodium titanate (Na.sub.2 TiO.sub.3), manganese (II) titanate (MnTiO.sub.3) and oxygen. The titanate mixture is treated with sodium hydroxide, in the presence of steam, to form sodium titanate, sodium manganate (III), water and hydrogen. The sodium titanate-manganate (III) mixture is treated with water to form sodium manganate (III), titanium dioxide and sodium hydroxide. Sodium manganate (III) and titanium dioxide are recycled following dissolution of sodium hydroxide in water.

Survival and stress responses of E. coli exposed to alkaline cleaners

USDA-ARS?s Scientific Manuscript database

Studies were undertaken to evaluate the effects of alkaline cleaners commonly used in food processing environments on survival and stress responses of the foodborne pathogen Escherichia coli O157:H7. Alkaline cleaners containing either sodium hydroxide or potassium hydroxide and hypochlorite had gre...

ATTENUATION/STABILIZATION OF ARSENIC BY IRON (HYDR)OXIDES IN SOILS/SEDIMENTS: LABORATORY STUDY.

EPA Science Inventory

Laboratory studies will be performed to assess the role of naturally occurring soil/sediment iron (hydr)oxides on the attenuation/stabilization of arsenic. Changes in the reversibility of arsenic partitioning will be assessed as a function of aging time using model experimental ...

On copper peroxide

NASA Technical Reports Server (NTRS)

Moser, L.

1988-01-01

The action of hydrogen superoxide on copper salts in alcoholic solutions is studied. The action of hydrogen peroxide on copper hydroxide in alcoholic suspensions, and the action of ethereal hydrogen peroxide on copper hydroxide are discussed. It is concluded that using the procedure proposed excludes almost entirely the harmful effect of hydrolysis.

Aluminum Coprecipitates with Fe (hydr)oxides: Does Isomorphous Substitution of Al3plus for Fe3plus in Goethite Occur

DOE Office of Scientific and Technical Information (OSTI.GOV)

E Bazilevskaya; D Archibald; M Aryanpour

2011-12-31

Iron (hydr)oxides are common in natural environments and typically contain large amounts of impurities, presumably the result of coprecipitation processes. Coprecipitation of Al with Fe (hydr)oxides occurs, for example, during alternating reduction-oxidation cycles that promote dissolution of Fe from Fe-containing phases and its re-precipitation as Fe-Al (hydr)oxides. We used chemical and spectroscopic analyses to study the formation and transformation of Al coprecipitates with Fe (hydr)oxides. In addition, periodic density functional theory (DFT) computations were performed to assess the structural and energetic effects of isolated or clustered Al atoms at 8 and 25 mol% Al substitution in the goethite structure. Coprecipitatesmore » were synthesized by raising the pH of dilute homogeneous solutions containing a range of Fe and Al concentrations (100% Fe to 100% Al) to 5. The formation of ferrihydrite in initial suspensions with {<=}20 mol% Al, and of ferrihydrite and gibbsite in initial suspensions with {>=}25 mol% Al was confirmed by infrared spectroscopic and synchrotron-based X-ray diffraction analyses. While base titrations showed a buffer region that corresponded to the hydrolysis of Fe in initial solutions with {<=}25 mol% Al, all of the Al present in these solutions was retained by the solid phases at pH 5, thus indicating Al coprecipitation with the primary Fe hydroxide precipitate. In contrast, two buffer regions were observed in solutions with 30 mol% Al (at pH {approx}2.25 for Fe{sup 3+} and at pH {approx}4 for Al{sup 3+}), suggesting the formation of Fe and Al (hydr)oxides as two separate phases. The Al content of initial coprecipitates influenced the extent of ferrihydrite transformation and of its transformation products as indicated by the presence of goethite, hematite and/or ferrihydrite in aged suspensions. DFT experiments showed that: (i) optimized unit cell parameters for Al-substituted goethites (8 and 25 Mol% Al) in clustered arrangement (i.e., the formation of diaspore-like clusters) were in good agreement with available experimental data whereas optimized unit cell parameters for isolated Al atoms were not, and (ii) Al-substituted goethites with Al in diaspore-like clusters resulted in more energetically favored structures. Combined experimental and DFT results are consistent with the coprecipitation of Al with Fe (hydr)oxides and with the formation of diaspore-like clusters, whereas DFT results suggest isomorphous Al for Fe substitution within goethite is unlike at 8 mol% Al substitution.« less

Visible-light-enhanced interactions of hydrogen sulfide with composites of zinc (oxy)hydroxide with graphite oxide and graphene.

PubMed

Seredych, Mykola; Mabayoje, Oluwaniyi; Bandosz, Teresa J

2012-01-17

Composites of zinc(oxy)hydroxide-graphite oxide and of zinc(oxy)hydroxide-graphene were used as adsorbents of hydrogen sulfide under ambient conditions. The initial and exhausted samples were characterized by XRD, FTIR, potentiometric titration, EDX, thermal analysis, and nitrogen adsorption. An increase in the amount of H(2)S adsorbed/oxidized on their surfaces in comparison with that of pure Zn(OH)(2) is linked to the structure of the composite, the relative number of terminal hydroxyls, and the kind of graphene-based phase used. Although terminal groups are activated by a photochemical process, the graphite oxide component owing to the chemical bonds with the zinc(oxy)hydroxide phase and conductive properties helps in electron transfer, leading to more efficient oxygen activation via the formation of superoxide ions. Elemental sulfur, zinc sulfide, sulfite, and sulfate are formed on the surface. The formation of sulfur compounds on the surface of zinc(oxy)hydroxide during the course of the breakthrough experiments and thus Zn(OH)(2)-ZnS heterojunctions can also contribute to the increased surface activity of our materials. The results show the superiority of graphite oxide in the formation of composites owing to its active surface chemistry and the possibility of interface bond formation, leading to an increase in the number of electron-transfer reactions. © 2011 American Chemical Society

Alkalinity of non-industrial cleaning products and the likelihood of producing significant esophageal burns.

PubMed

Howell, J M

1991-11-01

Alkaline cleaning products are a cause of serious esophageal injury. Over time, legislation has diminished the concentration of many such non-industrial solutions and solids; however several products presently do not list either the pH or relative concentrations of alkaline constituents. This study measures the pHs of several non-industrial cleaning products containing either ammonium chloride, sodium hydroxide, or potassium hydroxide. Three pH measurements were performed on each of 10 non-industrial alkaline cleaning products (eight liquid, two solid). Two 0.1% ammonium chloride solutions had pHs of 12.06 +/- 0.00 and 12.06 +/- 0.01, whereas a pH of 12.43 +/- 0.00 was recorded in a 0.2% ammonium chloride solution. Concentrations of sodium hydroxide and potassium hydroxide were listed on only one of five liquid cleaning product labels. The pHs for these five products varied between 12.83 +/- 0.009 and 13.5 +/- .0.2. The pHs of three sodium hydroxide solutions differed from values reported in Micromedex (Micromedex Inc, Denver CO) by up to 0.32 pH units. Ten percent (v/v) solutions of two solid lye products had pHs of 13.62 +/- 0.008 and 13.74 +/- 0.02. The investigator found that selected non-industrial cleaning products, including ammonia solutions, retain the ability to cause clinically important esophageal damage.

Hydroxide based Benzyltrimethylammonium degradation: Quantification of rates and degradation technique development

DOE PAGES

Sturgeon, Matthew R.; Macomber, Clay S.; Engtrakul, Chaiwat; ...

2015-01-21

Anion exchange membranes (AEMs) are of interest as hydroxide conducting polymer electrolytes in electrochemical devices like fuel cells and electrolyzers. AEMs require hydroxide stable covalently tetherable cations to ensure required conductivity. Benzyltrimethylammonium (BTMA) has been the covalently tetherable cation that has been most often employed in anion exchange membranes because it is reasonably basic, compact (limited number of atoms per charge), and easily/cheaply synthesized. Several reports exist that have investigated hydroxide stability of BTMA under specific conditions, but consistency within these reports and comparisons between them have not yet been made. While the hydroxide stability of BTMA has been believedmore » to be a limitation for AEMs, this stability has not been thoroughly reported. In this paper, we have found that several methods reported have inherent flaws in their findings due to the difficulty of performing degradation experiments at high temperature and high pH. In order to address these shortcomings, we have developed a reliable, standardized method of determining cation degradation under conditions similar/relevant to those expected in electrochemical devices. The experimental method has been employed to determine BTMA stabilities at varying cation concentrations and elevated temperatures, and has resulted in improved experimental accuracy and reproducibility. Finally and most notably, these results have shown that BTMA is quite stable at 80°C (half-life of ~4 years), a significant increase in stability over what had been reported previously.« less

The role of the chemical burns caused by hydroxide ion in the toxicity of dermal exposure to tetramethylammonium ion in a rat model.

PubMed

Wu, Chen-Long; Su, Shih-Bin; Lien, Hsiao-Yin; Guo, How-Ran

2012-11-01

To evaluate the role of the chemical burns caused by hydroxide ion in the fatal effects of tetramethylammonium ion (TMA) in dermal exposure to tetramethylammonium hydroxide (TMAH), we conducted a rat study consisting of two-step treatments with dermal exposure to NaOH and tetramethylammonium chloride (TMACl). In the first step, NaOH or saline was administered in the gauze on the shaved skin for 5 min, and in the second step, TMAH, TMACl, or saline was administered in the same way. The mean blood pressure (MBP), heart rate (HR), and survival in rats were compared among seven groups. Dermal exposure to saline and then 2.75 M TMACl introduced limited and temporary non-fatal effects. Exposure to 2.75 M NaOH and then saline had almost no effects and caused no deaths. Treatments with more concentrated NaOH or TMACl resulted in suppressions of MBP and HR, and deaths were observed after the dosing of TMACl. The toxicity of dermal exposure to TMA alone is limited, but fatal effects can be introduced by pre-treatment with hydroxide ion. Therefore, the chemical burn caused by hydroxide ion plays an essential role in the toxicity, implicating that effective neutralizing may help decreasing the fatality rate. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

Zinc (hydr)oxide/graphite oxide/AuNPs composites: role of surface features in H₂S reactive adsorption.

PubMed

Giannakoudakis, Dimitrios A; Bandosz, Teresa J

2014-12-15

Zinc hydroxide/graphite oxide/AuNPs composites with various levels of complexity were synthesized using an in situ precipitation method. Then they were used as H2S adsorbents in visible light. The materials' surfaces were characterized before and after H2S adsorption by various physical and chemical methods (XRD, FTIR, thermal analysis, potentiometric titration, adsorption of nitrogen and SEM/EDX). Significant differences in surface features and synergistic effects were found depending on the materials' composition. Addition of graphite oxide and the deposition of gold nanoparticles resulted in a marked increase in the adsorption capacity in comparison with that on the zinc hydroxide and zinc hydroxide/AuNP. Addition of AuNPs to zinc hydroxide led to a crystalline ZnO/AuNP composite while the zinc hydroxide/graphite oxide/AuNP composite was amorphous. The ZnOH/GO/AuNPs composite exhibited the greatest H2S adsorption capacity due to the increased number of OH terminal groups and the conductive properties of GO that facilitated the electron transfer and consequently the formation of superoxide ions promoting oxidation of hydrogen sulfide. AuNPs present in the composite increased the conductivity, helped with electron transfer to oxygen, and prevented the fast recombination of the electrons and holes. Copyright © 2014 Elsevier Inc. All rights reserved.

INFLUENCE OF IODOFORM ON ANTIMICROBIAL POTENTIAL OF CALCIUM HYDROXIDE

PubMed Central

Estrela, Carlos; Estrela, Cyntia Rodrigues de Araújo; Hollanda, Augusto César Braz; Decurcio, Daniel de Almeida; Pécora, Jesus Djalma

2006-01-01

The purpose of this research was to verify the influence of Iodoform on antimicrobial potential of calcium hydroxide. S. aureus, E. faecalis, P. aeruginosa, B. subtilis, C. albicans were the biological indicators. The substances tested were: calcium hydroxide + saline; calcium hydroxide + Iodoform + saline; Iodoform + saline. For the agar diffusion test, 18 Petri plates with 20 ml of BHI agar were inoculated with the microbial suspensions. Fifty-four cavities were made and filled with the substances tested. The diameters of microbial inhibition were then measured. In direct exposure test, 162 #50 sterile absorbent paper points were immersed in the experimental suspensions for 5 min, and covered with the pastes. At intervals of 24, 48 and 72 hours, the paper points were immersed in 10 ml of Letheen Broth, followed by incubation at 37°°C for 48h. Microbial growth was evaluated by turbidity of the culture medium. A 0.1 ml inoculum obtained from the Letheen Broth was transferred to 7 ml of BHI, and incubated at 37°°C for 48h. Bacterial growth was again evaluated by turbidity of the culture medium. The calcium hydroxide associated with the saline or the iodoform plus saline showed antimicrobial effectiveness in both experimental methods. The iodoform paste presented antimicrobial ineffectiveness for the agar diffusion test on all biological microorganisms and for the direct exposure test on B. subtilis and on the mixture. PMID:19089027

The relationship between structural stability and electrochemical performance of multi-element doped alpha nickel hydroxide

NASA Astrophysics Data System (ADS)

Miao, Chengcheng; Zhu, Yanjuan; Huang, Liangguo; Zhao, Tengqi

2015-01-01

The multi-element doped alpha nickel hydroxide has been prepared by supersonic co-precipitation method. Three kinds of samples A, B and C are prepared by chemically coprecipitating Ni/Al, Ni/Al/Mn and Ni/Al/Mn/Yb, respectively. Inductively coupled plasma atomic emission spectroscopy (ICP-AES), Particle size distribution (PSD) measurement, X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR) are used to characterize the physical properties of the synthesized α-Ni(OH)2 samples, such as chemical composition, morphology, structural stability of the crystal. The results show that all samples are nano-sized materials and the interlayer spacing becomes larger and the structural stability becomes better with the increase of doped elements and doped ratio. The prepared alpha nickel hydroxide samples are added into micro-sized beta nickel hydroxide to form biphase electrode materials for Ni-MH battery. The electrochemical characterization of the biphase electrodes, including cyclic voltammetry (CV) and charge/discharge test, are also performed. The results demonstrate that the biphase electrode with sample C exhibits better electrochemical reversibility and cyclic stability, higher charge efficient and discharge potential, larger proton diffusion coefficient (5.81 × 10-12 cm2 s-1) and discharge capacity (309.0 mAh g-1). Hence, it indicates that all doped elements can produce the synergic effect and further improve the electrochemical properties of the alpha nickel hydroxide.

Determination of cadmium in grains by isotope dilution ICP-MS and coprecipitation using sample constituents as carrier precipitants.

PubMed

Inagaki, Kazumi; Narukawa, Tomohiro; Yarita, Takashi; Takatsu, Akiko; Okamoto, Kensaku; Chiba, Koichi

2007-10-01

A coprecipitation method using sample constituents as carrier precipitants was developed that can remove molybdenum, which interferes with the determination of cadmium in grain samples via isotope dilution inductively coupled plasma mass spectrometry (ID-ICPMS). Samples were digested with HNO3, HF, and HClO4, and then purified 6 M sodium hydroxide solution was added to generate colloidal hydrolysis compounds, mainly magnesium hydroxide. Cadmium can be effectively separated from molybdenum because the cadmium forms hydroxides and adsorbs onto and/or is occluded in the colloid, while the molybdenum does not form hydroxides or adsorb onto the hydrolysis colloid. The colloid was separated by centrifugation and then dissolved with 0.2 M HNO3 solution to recover the cadmium. The recovery of Cd achieved using the coprecipitation was >97%, and the removal efficiency of Mo was approximately 99.9%. An extremely low procedural blank (below the detection limit of ICPMS) was achieved by purifying the 6 M sodium hydroxide solution via Mg coprecipitation using Mg(NO3)2 solution. The proposed method was applied to two certified reference materials (NIST SRM 1567a wheat flour and SRM 1568a rice flour) and CCQM-P64 soybean powder. Good analytical results with small uncertainties were obtained for all samples. This method is simple and reliable for the determination of Cd in grain samples by ID-ICPMS.

Efficient Sorption and Removal of Perfluoroalkyl Acids (PFAAs) from Aqueous Solution by Metal Hydroxides Generated in Situ by Electrocoagulation.

PubMed

Lin, Hui; Wang, Yujuan; Niu, Junfeng; Yue, Zhihan; Huang, Qingguo

2015-09-01

Removal of environmentally persistent perfluoroalkyl acids (PFAAs), that is, perfluorooctanesulfonate (PFOS) and perfluorocarboxylic acids (PFCAs, C4 ∼ C10) were investigated through sorption on four metal hydroxide flocs generated in situ by electrocoagulation in deionized water with 10 mM NaCl as supporting electrolyte. The results indicated that the zinc hydroxide flocs yielded the highest removal efficiency with a wide range concentration of PFOA/PFOS (1.5 μM ∼ 0.5 mM) at the zinc dosage <150 mg L(-1) with the energy consumption <0.18 Wh L(-1). The sorption kinetics indicated that the zinc hydroxide flocs had an equilibrium adsorbed amount (qe) up to 5.74/7.69 mmol g(-1) (Zn) for PFOA/PFOS at the initial concentration of 0.5 mM with an initial sorption rate (v0) of 1.01 × 10(3)/1.81 × 10(3) mmol g(-1) h(-1). The sorption of PFOA/PFOS reached equilibrium within <10 min. The sorption mechanisms of PFAAs on the zinc hydroxide flocs were proposed based on the investigation of various driving forces. The results indicated that the hydrophobic interaction was primarily responsible for the PFAAs sorption. The electrocoagulation process with zinc anode may have a great potential for removing PFAAs from industrial wastewater as well as contaminated environmental waterbody.

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2010 CFR

2010-07-01

... - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine (PMN P-00...

21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Alumina (dried aluminum hydroxide). 73.1010 Section 73.1010 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum...

21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Alumina (dried aluminum hydroxide). 73.1010 Section 73.1010 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum...

21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Alumina (dried aluminum hydroxide). 73.1010 Section 73.1010 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum...

TRANSFORMATION AND MOBILIZATION OF ARSENIC ADSORBED ON GRANULAR FERRIC HYDROXIDE UNDER BIO-REDUCTIVE CONDITIONS

EPA Science Inventory

Biotic and abiotic reduction of arsenic (V) and iron (III) influences the partioning of arsenic (As) between the solid and aqueous phases in soils, sediments and wastes. In this study, laboratory experiments on arsenic adsorbed on granular ferric hydroxide (GFH) was performed to ...

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2011 CFR

2011-07-01

... - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine (PMN P-00...

STS-116 crewmembers Oefelin and Curbeam, Jr., work with lithium hydroxide in the MDDK on Space Shuttle Discovery

NASA Image and Video Library

2006-12-10

S116-E-05293 (10 Dec. 2006) --- Astronauts William A. (Bill) Oefelein (bottom) and Robert L. Curbeam, Jr., STS-116 pilot and mission specialist, respectively, work with the lithium hydroxide (LiOH) canisters beneath Space Shuttle Discovery's middeck.

Improved fuel-cell-type hydrogen sensor

NASA Technical Reports Server (NTRS)

Rudek, F. P.; Rutkowski, M. D.

1968-01-01

Modified hydrogen sensor replaces oxygen cathode with a cathode consisting of a sealed paste of gold hydroxide and a pure gold current collector. The net reaction which occurs during cell operation is the reduction of the gold hydroxide to gold and water, with a half-cell potential of 1.4 volts.

ANAEROBIC BIODEGRADATION OF VEGETABLE OIL AND ITS METABOLIC INTERMEDIATES IN OIL-ENRICHED FRESHWATER SEDIMENTS

EPA Science Inventory

Anaerobic biodegradation of vegetable oil in freshwater sediments is strongly inhibited by high concentrations of oil, but the presence of ferric hydroxide relieves the inhibition. The effect of ferric hydroxide is not due to physical or chemical interactions with long-chain fatt...

Multiple and configurable optical logic systems based on layered double hydroxides and chromophore assemblies.

PubMed

Shi, Wenying; Fu, Yi; Li, Zhixiong; Wei, Min

2015-01-14

Multiple and configurable fluorescence logic gates were fabricated via self-assembly of layered double hydroxides and various chromophores. These logic gates were operated by observation of different emissions with the same excitation wavelength, which achieve YES, NOT, AND, INH and INHIBIT logic operations, respectively.

21 CFR 172.814 - Hydroxylated lecithin.

Code of Federal Regulations, 2011 CFR

2011-04-01

... whereby the separated fatty acid fraction of the resultant product has an acetyl value of 30 to 38: (1) With hydrogen peroxide, benzoyl peroxide, lactic acid, and sodium hydroxide. (2) With hydrogen peroxide, acetic acid, and sodium hydroxide. (b) It is used or intended for use, in accordance with good...

Role of lauric acid-potassium hydroxide concentration on bacterial contamination of spray washed broiler carcasses

USDA-ARS?s Scientific Manuscript database

A series of experiments were conducted to examine reductions in bacterial contamination of broiler carcasses washed in a spray cabinet with various concentrations of lauric acid (LA)-potassium hydroxide (KOH) solutions. Fifty eviscerated carcasses and 5 ceca were obtained from the processing line of...

METHOD OF PROCESSING MONAZITE SAND

DOEpatents

Calkins, G.D.

1957-10-29

A method is given for the pretreatment of monazite sand with sodium hydroxide. When momazite sand is reacted with sodium hydroxide, the thorium, uranium, and rare earths are converted to water-insoluble hydrous oxides; but in the case of uranium, the precipitate compound may at least partly consist of a slightly soluble uranate. According to the patent, monazite sand is treated with an excess of aqueous sodium hydroxide solution, and the insoluble compounds of thorium, uranium, and the rare earths are separated from the aqueous solution. This solution is then concentrated causing sodium phosphate to crystallize out. The crystals are removed from the remaining solution, and the solution is recycled for reaction with a mew supply of momazite sand.

Method for hot pressing beryllium oxide articles

DOEpatents

Ballard, Ambrose H.; Godfrey, Jr., Thomas G.; Mowery, Erb H.

1988-01-01

The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide-lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

Optical properties of cerium oxide (CeO2) nanoparticles synthesized by hydroxide mediated method

NASA Astrophysics Data System (ADS)

Ali, Mawlood Maajal; Mahdi, Hadeel Salih; Parveen, Azra; Azam, Ameer

2018-05-01

The nanoparticles of cerium oxide have been successfully synthesized by hydroxide mediated method, using cerium nitrate and sodium hydroxide as precursors. The microstructural properties were analyzed by X-ray diffraction technique (XRD). The X-ray diffraction results show that the cerium oxide nanoparticles were in cubic structure. The optical absorption spectra of cerium oxide were recorded by UV-VIS spectrophotometer in the range of 320 to 600 nm and photoluminescence spectra in the range of 400-540 nm and have been presented. The energy band gap was determined by Tauc relationship. The crystallite size was determined from Debye-Scherer equation and came out to be 6.4 nm.

Thermochemical generation of hydrogen and oxygen from water. [NaMnO/sub 2/ and TiO/sub 2/

DOEpatents

Robinson, P.R.; Bamberger, C.E.

1980-02-08

A thermochemical cyclic process for the production of hydrogen exploits the reaction between sodium manganate (NaMnO/sub 2/) and titanium dioxide (TiO/sub 2/) to form sodium titanate (Na/sub 2/TiO/sub 3/), manganese (II) titanate (MnTiO/sub 3/) and oxygen. The titanate mixture is treated with sodium hydroxide, in the presence of steam, to form sodium titanate, sodium manganate (III), water and hydrogen. The sodium titanate-manganate (III) mixture is treated with water to form sodium manganate (III), titanium dioxide and sodium hydroxide. Sodium manganate (III) and titanium dioxide are recycled following dissolution of sodium hydroxide in water.

Method for the safe disposal of alkali metal

DOEpatents

Johnson, Terry R.

1977-01-01

Alkali metals such as those employed in liquid metal coolant systems can be safely reacted to form hydroxides by first dissolving the alkali metal in relatively inert metals such as lead or bismuth. The alloy thus formed is contacted with a molten salt including the alkali metal hydroxide and possibly the alkali metal carbonate in the presence of oxygen. This oxidizes the alkali metal to an oxide which is soluble within the molten salt. The salt is separated and contacted with steam or steam-CO.sub.2 mixture to convert the alkali metal oxide to the hydroxide. These reactions can be conducted with minimal hydrogen evolution and with the heat of reaction distributed between the several reaction steps.

Nickel hydroxide positive electrode for alkaline rechargeable battery

DOEpatents

Young, Kwo; Wang, Lixin; Mays, William; Reichman, Benjamin; Chao-Ian, Hu; Wong, Diana; Nei, Jean

2018-04-03

Certain nickel hydroxide active cathode materials for use in alkaline rechargeable batteries are capable of transferring >1.3 electrons per Ni atom under reversible electrochemical conditions. The specific capacity of the nickel hydroxide active materials is for example .gtoreq.325 mAh/g. The cathode active materials exhibit an additional discharge plateau near 0.8 V vs. a metal hydride (MH) anode. Ni in an oxidation state of less than 2, such as Ni.sup.1+, is able to participate in electrochemical reactions when using the present cathode active materials. It is possible that up to 2.3 electrons, up to 2.5 electrons or more may be transferred per Ni atom under electrochemical conditions.

Nickel hydroxide positive electrode for alkaline rechargeable battery

DOEpatents

Young, Kwo; Wang, Lixin; Mays, William; Reichman, Benjamin; Chao-Ian, Hu; Wong, Diana; Nei, Jean

2018-02-20

Certain nickel hydroxide active cathode materials for use in alkaline rechargeable batteries are capable of transferring >1.3 electrons per Ni atom under reversible electrochemical conditions. The specific capacity of the nickel hydroxide active materials is for example .gtoreq.325 mAh/g. The cathode active materials exhibit an additional discharge plateau near 0.8 V vs. a metal hydride (MH) anode. Ni in an oxidation state of less than 2, such as Ni.sup.1+, is able to participate in electrochemical reactions when using the present cathode active materials. It is possible that up to 2.3 electrons, up to 2.5 electrons or more may be transferred per Ni atom under electrochemical conditions.

Synthesis of neodymium hydroxide nanotubes and nanorods by soft chemical process.

PubMed

Shi, Weidong; Yu, Jiangbo; Wang, Haishui; Yang, Jianhui; Zhang, Hongjie

2006-08-01

A facile soft chemical approach using cetyltrimethylammonium bromide (CTAB) as template is successfully designed for synthesis of neodymium hydroxide nanotubes. These nanotubes have an average outer diameter around 20 nm, inner diameter around 2 nm, and length ranging from 100 to 120 nm, high BET surface area of 495.71 m(2) g(-1). We also find that neodymium hydroxide nanorods would be obtained when CTAB absented in reaction system. The Nd(OH)3 nanorods might act as precursors that are converted into Nd2O3 nanorods through dehydration at 550 degrees C. The nanorods could exhibit upconversion emission characteristic under excitation of 591 nm at room temperature.

Aqueous Ammonia or Ammonium Hydroxide? Identifying a Base as Strong or Weak

ERIC Educational Resources Information Center

Sanger, Michael J.; Danner, Matthew

2010-01-01

When grocery stores sell solutions of ammonia, they are labeled "ammonia"; however, when the same solution is purchased from chemical supply stores, they are labeled "ammonium hydroxide". The goal of this experiment is for students to determine which name is more appropriate. In this experiment, students use several different experimental methods…

Engineering evaluation of a sodium hydroxide thermal energy storage module

NASA Technical Reports Server (NTRS)

Perdue, D. G.; Gordon, L. H.

1980-01-01

An engineering evaluation of thermal energy storage prototypes was performed in order to assess the development status of latent heat storage media. The testing and the evaluation of a prototype sodium hydroxide module is described. This module stored off-peak electrical energy as heat for later conversion to domestic hot water needs.

21 CFR 73.2326 - Chromium hydroxide green.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Chromium hydroxide green. 73.2326 Section 73.2326 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF... in coloring externally applied cosmetics, including those intended for use in the area of the eye, in...

21 CFR 73.2326 - Chromium hydroxide green.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Chromium hydroxide green. 73.2326 Section 73.2326 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF... in coloring externally applied cosmetics, including those intended for use in the area of the eye, in...

Evaluation of Military Field-Water Quality. Volume 3. Opportunity Poisons

DTIC Science & Technology

1987-12-01

Acidic chemical cleaners fluoric acid, nitric acid, perchloric Spent acid acid, sulfuric acid Alkalies Miscellaneous caustic products Ammonia, lime...calcium oxide), potassium Alkaline battery fluid hydroxide, sodium hydroxide, sodium Caustic wastewater silicate Cleaning solutions Lye Nonhalogenated...Laboratory chemicals chloride, polychlorinated biphenyls, zinc Paint and varnish removers naphthenate , copper naphthenate , dichloro- Capacitors and

In Situ Clay Formation: Evaluation of a Proposed New Technology for Stable Containment Barriers

DTIC Science & Technology

2004-03-01

situ layered double hydroxide precipitation........... 23 4.2.1 Solution preparation and column mixing...22 Table 4.2 Summary of in situ precipitation of layered double hydroxide (LDH...effect on permeability for the smallest volume precipitated is sheet silicates or layered -clay phases (hereafter called “clays”). In natural

Recycling Lithium Carbonate/Lithium Hydroxide Waste

NASA Technical Reports Server (NTRS)

Flowers, J.; Flowers, J.

1983-01-01

Hazardous waste disposal problem eliminated by regeneration. Li2CO3/ LiOH recycling process relies on low solubility of alkali carbonates in corresponding hydroxides. Li2CO3 precipitate calcined to LI2O, then rehydrated LiOH. Regeneration eliminates need to dispose caustic waste and uses less energy than simple calcination of entire waste mass.

Periodicity in the Acid-Base Behavior of Oxides and Hydroxides.

ERIC Educational Resources Information Center

Rich, Ronald L.

1985-01-01

Aqueous solubilities of many important hydrous oxides and hydroxides are displayed, for the various elements, as functions primarily of pH. These graphs are then arranged in groups to facilitate studies of the effects of oxidation state, electron structure, and position in the periodic table, along with size and coordination number. (JN)

Room temperature synthesis of free-standing HKUST-1 membranes from copper hydroxide nanostrands for gas separation.

PubMed

Mao, Yiyin; shi, Li; Huang, Hubiao; Cao, Wei; Li, Junwei; Sun, Luwei; Jin, Xianda; Peng, Xinsheng

2013-06-25

Large scale, robust, well intergrown free-standing HKUST-1 membranes were converted from copper hydroxide nanostrand free-standing films in 1,3,5-benzenetricarboxylic acid water-ethanol solution at room temperature, and explored for gas separation. The truncated crystals are controllable and favorable for the dense intergrowth.

21 CFR 184.1631 - Potassium hydroxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... thickener as defined in § 170.3(o)(28) of this chapter. (2) The ingredient is used in food at levels not to... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Potassium hydroxide. 184.1631 Section 184.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...

Influence of washing time on residual contamination of carcasses sprayed with lauric acid-potassium hydroxide.

USDA-ARS?s Scientific Manuscript database

A series of experiments were conducted to examine reductions in bacterial contamination of broiler carcasses washed for various times in a spray cabinet with a 2% lauric acid (LA)-1% potassium hydroxide (KOH) (w/v) solution. Forty eviscerated carcasses and 5 ceca were obtained from the processing l...

Extraction of Ni (II) from Spent Hydrodesulfurization HDS Catalyst Through Leaching and Electroless Precipitation of Ni(OH)2

NASA Astrophysics Data System (ADS)

Pradhan, Sangita R.; Dash, Barsha; Sanjay, Kali; Subbaiah, T.

2013-04-01

The extraction of nickel (II) from a spent hydro-desulfurization catalyst containing 11.6 pct Ni was carried out through sulfuric acid leaching. Variations of parameters such as the concentration of acid, temperature, and time, were studied and optimized. Nickel hydroxide was precipitated from the leach liquor via neutralization with 1 M sodium hydroxide up to pH 12 in three different methods: normal neutralization precipitation, and then neutralization precipitation followed by aging at 353 K (80 °C) for 4 hours and neutralization of the leach liquor with 10 pct (v/v) of 0.1 N sodium lauryl sulfate. X-ray diffraction (XRD) and transmission electron microscopy (TEM) microanalysis shows a difference in crystallinity with the method of precipitation. The nickel hydroxide contains Cu(II), Co(II), Zn(II), and Mn(II) as trace impurities. The discharge capacities of the precipitated nickel hydroxides were 120 mAhg-1, 140.72 mAhg-1, and 145.2 mAhg-1 for aged sample, sample without surfactant, and with surfactant respectively.

Accidental injury of the inferior alveolar nerve due to the extrusion of calcium hydroxide in endodontic treatment: a case report

PubMed Central

2016-01-01

During clinical endodontic treatment, we often find radiopaque filling material beyond the root apex. Accidental extrusion of calcium hydroxide could cause the injury of inferior alveolar nerve, such as paresthesia or continuous inflammatory response. This case report presents the extrusion of calcium hydroxide and treatment procedures including surgical intervention. A 48 yr old female patient experienced Calcipex II extrusion in to the inferior alveolar canal on left mandibular area during endodontic treatment. After completion of endodontic treatment on left mandibular first molar, surgical intervention was planned under general anesthesia. After cortical bone osteotomy and debridement, neuroma resection and neurorrhaphy was performed, and prognosis was observed. But no improvement in sensory nerve was seen following surgical intervention after 20 mon. A clinician should be aware of extrusion of intracanal medicaments and the possibility of damage on inferior alveolar canal. Injectable type of calcium hydroxide should be applied with care for preventing nerve injury. The alternative delivery method such as lentulo spiral was suggested on the posterior mandibular molar. PMID:26877992

Hydroxide Self-Feeding High-Temperature Alkaline Direct Formate Fuel Cells.

PubMed

Li, Yinshi; Sun, Xianda; Feng, Ying

2017-05-22

Conventionally, both the thermal degradation of the anion-exchange membrane and the requirement of additional hydroxide for fuel oxidation reaction hinder the development of the high-temperature alkaline direct liquid fuel cells. The present work addresses these two issues by reporting a polybenzimidazole-membrane-based direct formate fuel cell (DFFC). Theoretically, the cell voltage of the high-temperature alkaline DFFC can be as high as 1.45 V at 90 °C. It has been demonstrated that a proof-of-concept alkaline DFFC without adding additional hydroxide yields a peak power density of 20.9 mW cm -2 , an order of magnitude higher than both alkaline direct ethanol fuel cells and alkaline direct methanol fuel cells, mainly because the hydrolysis of formate provides enough OH - ions for formate oxidation reaction. It was also found that this hydroxide self-feeding high-temperature alkaline DFFC shows a stable 100 min constant-current discharge at 90 °C, proving the conceptual feasibility. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microbial mediated iron redox cycling in Fe (hydr)oxides for nitrite removal.

PubMed

Lu, Yongsheng; Xu, Lu; Shu, Weikang; Zhou, Jizhi; Chen, Xueping; Xu, Yunfeng; Qian, Guangren

2017-01-01

Nitrite, at an environmentally relevant concentration, was significantly reduced with iron (hydr)oxides mediated by Shewanella oneidensis MR-1. The average nitrite removal rates of 1.28±0.08 and 0.65±0.02(mgL -1 )h -1 were achieved with ferrihydrite and magnetite, respectively. The results showed that nitrite removal was able to undergo multiple redox cycles with iron (hydr)oxides mediated by Shewanella oneidensis MR-1. During the bioreduction of the following cycles, biogenic Fe(II) was subsequently chemically oxidized to Fe(III), which is associated with nitrite reduction. There was 11.18±1.26mgL -1 of NH 4 + -N generated in the process of redox cycling of ferrihydrite. Additionally, results obtained by using X-ray diffraction showed that ferrihydrite and magnetite remained mainly stable in the system. This study indicated that redox cycling of Fe in iron (hydr)oxides was a potential process associated with NO 2 - -N removal from solution, and reduced most nitrite abiotically to gaseous nitrogen species. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of food and various antacids on the absorption of tenoxicam.

PubMed Central

Day, R O; Lam, S; Paull, P; Wade, D

1987-01-01

1 Twelve healthy volunteers received a single oral dose of tenoxicam 20 mg on six occasions separated by 3 weeks. 2 The six occasions were: fasted overnight; postprandial; fasting and 15 ml aluminium hydroxide gel; postprandial and 15 ml aluminium hydroxide gel; fasting and 15 ml aluminium and magnesium hydroxide gel; postprandial and 15 ml aluminium and magnesium hydroxide gel. 3 Twenty plasma samples were collected over 15 days following dosing with tenoxicam. 4 The following kinetic parameters for plasma tenoxicam were compared: peak concentrations, time taken to reach peak concentrations, area under the plasma concentration-time curve (AUC) and half-life of elimination. 5 Food lengthened the time taken to reach peak tenoxicam concentrations (5.82 +/- 4.6 vs 1.84 +/- 1.0 h in the fasting state; P less than 0.02) and marginally reduced the peak concentrations achieved. AUC was not affected by any of the different regimens. 6 These effects of food on tenoxicam bioavailability are unlikely to be of clinical significance during chronic dosing with the drug. PMID:3499163

Low-crystalline iron oxide hydroxide nanoparticle anode for high-performance supercapacitors

PubMed Central

Owusu, Kwadwo Asare; Qu, Longbing; Li, Jiantao; Wang, Zhaoyang; Zhao, Kangning; Yang, Chao; Hercule, Kalele Mulonda; Lin, Chao; Shi, Changwei; Wei, Qiulong; Zhou, Liang; Mai, Liqiang

2017-01-01

Carbon materials are generally preferred as anodes in supercapacitors; however, their low capacitance limits the attained energy density of supercapacitor devices with aqueous electrolytes. Here, we report a low-crystalline iron oxide hydroxide nanoparticle anode with comprehensive electrochemical performance at a wide potential window. The iron oxide hydroxide nanoparticles present capacitances of 1,066 and 716 F g−1 at mass loadings of 1.6 and 9.1 mg cm−2, respectively, a rate capability with 74.6% of capacitance retention at 30 A g−1, and cycling stability retaining 91% of capacitance after 10,000 cycles. The performance is attributed to a dominant capacitive charge-storage mechanism. An aqueous hybrid supercapacitor based on the iron oxide hydroxide anode shows stability during float voltage test for 450 h and an energy density of 104 Wh kg−1 at a power density of 1.27 kW kg−1. A packaged device delivers gravimetric and volumetric energy densities of 33.14 Wh kg−1 and 17.24 Wh l−1, respectively. PMID:28262797

Effects of ammonium hydroxide on the structure and gas adsorption of nanosized Zr-MOFs (UiO-66).

PubMed

Abid, Hussein Rasool; Ang, Ha Ming; Wang, Shaobin

2012-05-21

Several zirconium-based metal-organic frameworks (Zr-MOFs) have been synthesized using ammonium hydroxide as an additive in the synthesis process. Their physicochemical properties have been characterized by N(2) adsorption/desorption, XRD, SEM, FTIR, and TGA, and their application in CO(2) adsorption was evaluated. It was found that addition of ammonium hydroxide produced some effects on the structure and adsorption behavior of Zr-MOFs. The pore size and pore volume of Zr-MOFs were enhanced with the additive, however, specific surface area of Zr-MOFs was reduced. Using an ammonium hydroxide additive, the crystal size of Zr-MOF was reduced with increasing amount of the additive. All the samples presented strong thermal stability. Adsorption tests showed that capacity of CO(2) adsorption on the Zr-MOFs under standard conditions was reduced due to decreased micropore fractions. However, modified Zr-MOFs had significantly lower adsorption heat. The adsorption capacity of carbon dioxide was increased at high pressure, reaching 8.63 mmol g(-1) at 987 kPa for Zr-MOF-NH(4)-2.

Calcium leaching behavior of cementitious materials in hydrochloric acid solution.

PubMed

Yang, Huashan; Che, Yujun; Leng, Faguang

2018-06-11

The calcium leaching behavior of cement paste and silica fume modified calcium hydroxide paste, exposed to hydrochloric acid solution, is reported in this paper. The kinetic of degradation was assessed by the changes of pH of hydrochloric acid solution with time. The changes of compressive strength of specimens in hydrochloric acid with time were tested. Hydration products of leached specimens were also analyzed by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric (TG), and atomic force microscope (AFM). Tests results show that there is a dynamic equilibrium in the supply and consumption of calcium hydroxide in hydrochloric acid solution, which govern the stability of hydration products such as calcium silicate hydrate (C-S-H). The decrease of compressive strength indicates that C-S-H are decomposed due to the lower concentration of calcium hydroxide in the pore solution than the equilibrium concentration of the hydration products. Furthermore, the hydration of unhydrated clinker delayed the decomposition of C-S-H in hydrochloric acid solution due to the increase of calcium hydroxide in pore solution of cementitious materials.

A practical method for measuring the ion exchange capacity decrease of hydroxide exchange membranes during intrinsic degradation

NASA Astrophysics Data System (ADS)

Kreuer, Klaus-Dieter; Jannasch, Patric

2018-01-01

In this work we present a practical thermogravimetric method for quantifying the IEC (ion exchange capacity) decrease of hydroxide exchange membranes (HEMs) during intrinsic degradation mainly occurring through nucleophilic attack of the anion exchanging group by hydroxide ions. The method involves measuring weight changes under controlled temperature and relative humidity. These conditions are close to these in a fuel cell, i.e. the measured degradation rate includes all effects originating from the polymeric structure, the consumption of hydroxide ions and the release of water. In particular, this approach involves no added solvents or base, thereby avoiding inaccuracies that may arise in other methods due to the presence of solvents (other than water) or co-ions (such as Na+ or K+). We demonstrate the method by characterizing the decomposition of membranes consisting of poly(2,6-dimethyl-1,4-phenylene oxide) functionalized with trimethyl-pentyl-ammonium side chains. The decomposition rate is found to depend on temperature, relative humidity RH (controlling the hydration number λ) and the total water content (controlled by the actual IEC and RH).

Study on Kinetic Mechanism of Bastnaesite Concentrates Decomposition Using Calcium Hydroxide

NASA Astrophysics Data System (ADS)

Cen, Peng; Wu, Wenyuan; Bian, Xue

2018-06-01

The thermal decomposition of bastnaesite concentrates using calcium hydroxide was studied. Calcium hydroxide can effectively inhibit the emission of fluorine during roasting by transforming it to calcium fluoride. The decomposition rate increased with increasing reaction temperature and amount of calcium hydroxide. The decomposition kinetics were investigated. The decomposition reaction was determined to be a heterogeneous gas-solid reaction, and it followed an unreacted shrinking core model. By means of the integrated rate equation method, the reaction was proven to be kinetically first order. Different reaction models were fit to the experimental data to determine the reaction control process. The chemical reaction at the phase interface controlled the reaction rate in the temperatures ranging from 673 K to 773 K (400 °C to 500 °C) with an apparent activation energy of 82.044 kJ·mol-1. From 773 K to 973 K (500 °C to 700 °C), diffusion through the solid product's layer became the determining step, with a lower activation energy of 15.841 kJ·mol-1.

Subnanometer Cobalt-Hydroxide-Anchored N-Doped Carbon Nanotube Forest for Bifunctional Oxygen Catalyst.

PubMed

Kim, Ji Eun; Lim, Joonwon; Lee, Gil Yong; Choi, Sun Hee; Maiti, Uday Narayan; Lee, Won Jun; Lee, Ho Jin; Kim, Sang Ouk

2016-01-27

Electrochemical oxygen redox reactions are the crucial elements for energy conversion and storage including fuel cells and metal air batteries. Despite tremendous research efforts, developing high-efficient, low-cost, and durable bifunctional oxygen catalysts remains a major challenge. We report a new class of hybrid material consisting of subnanometer thick amorphous cobalt hydroxide anchored on NCNT as a durable ORR/OER bifunctional catalyst. Although amorphous cobalt species-based catalysts are known as good OER catalysts, hybridizing with NCNT successfully enhanced ORR activity by promoting a 4e reduction pathway. Abundant charge carriers in amorphous cobalt hydroxide are found to trigger the superior OER activity with high current density and low Tafel slope as low as 36 mV/decade. A remarkably high OER turnover frequency (TOF) of 2.3 s(-1) at an overpotential of 300 mV was obtained, one of the highest values reported so far. Moreover, the catalytic activity was maintained over 120 h of cycling. The unique subnanometer scale morphology of amorphous hydroxide cobalt species along with intimate cobalt species-NCNT interaction minimizes the deactivation of catalyst during prolonged repeated cycles.

[Calcium carbonate for the treatment of hyperphosphatemia in chronic hemodialysis patients].

PubMed

Kiss, D; Battegay, M; Meier, C; Lyrer, A

1990-03-03

Hyperphosphatemia in chronic hemodialysis patients is usually treated with aluminium containing phosphate binders. In recent years there has been increasing evidence of serious complications due to aluminium accumulation. We have investigated a new calcium carbonate preparation with an HCl-resistant capsule designed to prevent gastrointestinal side effects. Its phosphate binding capacity in comparison to aluminium chloride hydroxide was investigated in 17 chronic hemodialysis patients. The dose of the phosphate binder was adjusted regularly so that the serum phosphorus levels were below 1.8 mmol/l. The mean dose of aluminium chloride hydroxide was 3.36 g/day and of calcium carbonate 4.96 g/day. The mean (+/- SD) serum calcium level was 2.58 +/- 0.11 mmol/l under aluminium chloride hydroxide and 2.50 +/- 0.25 mmol/l under calcium carbonate. The mean phosphorus level was 1.69 +/- 0.31 mmol/l under aluminium chloride hydroxide and 1.71 +/- 0.33 under calcium carbonate. Serum aluminium fell from 64.5 +/- 14.4 micrograms/l to 28.5 +/- 17.5 micrograms/l after 3 months.

Tailoring transition-metal hydroxides and oxides by photon-induced reactions

DOE PAGES

Niu, Kai -Yang; Fang, Liang; Ye, Rong; ...

2016-10-18

Controlled synthesis of transition-metal hydroxides and oxides with earth-abundant elements have attracted significant interest because of their wide applications, for example as battery electrode materials or electrocatalysts for fuel generation. Here, we report the tuning of the structure of transition-metal hydroxides and oxides by controlling chemical reactions using an unfocused laser to irradiate the precursor solution. A Nd:YAG laser with wavelengths of 532 nm or 1064 nm was used. The Ni 2+, Mn 2+, and Co 2+ ion-containing aqueous solution undergoes photo-induced reactions and produces hollow metal-oxide nanospheres (Ni 0.18Mn 0.45Co 0.37O x) or core–shell metal hydroxide nanoflowers ([Ni 0.15Mnmore » 0.15Co 0.7(OH) 2](NO 3) 0.2•H 2O), depending on the laser wavelengths. We propose two reaction pathways, either by photo-induced redox reaction or hydrolysis reaction, which are responsible for the formation of distinct nanostructures. As a result, the study of photon-induced materials growth shines light on the rational design of complex nanostructures with advanced functionalities.« less

Different arsenate and phosphate incorporation effects on the nucleation and growth of iron(III) (Hydr)oxides on quartz.

PubMed

Neil, Chelsea W; Lee, Byeongdu; Jun, Young-Shin

2014-10-21

Iron(III) (hydr)oxides play an important role in the geochemical cycling of contaminants in natural and engineered aquatic systems. The ability of iron(III) (hydr)oxides to immobilize contaminants can be related to whether the precipitates form heterogeneously (e.g., at mineral surfaces) or homogeneously in solution. Utilizing grazing incidence small-angle X-ray scattering (GISAXS), we studied heterogeneous iron(III) (hydr)oxide nucleation and growth on quartz substrates for systems containing arsenate and phosphate anions. For the iron(III) only system, the radius of gyration (Rg) of heterogeneously formed precipitates grew from 1.5 to 2.5 (± 1.0) nm within 1 h. For the system containing 10(-5) M arsenate, Rg grew from 3.6 to 6.1 (± 0.5) nm, and for the system containing 10(-5) M phosphate, Rg grew from 2.0 to 4.0 (± 0.2) nm. While the systems containing these oxyanions had more growth, the system containing only iron(III) had the most nucleation events on substrates. Ex situ analyses of homogeneously and heterogeneously formed precipitates indicated that precipitates in the arsenate system had the highest water content and that oxyanions may bridge iron(III) hydroxide polymeric embryos to form a structure similar to ferric arsenate or ferric phosphate. These new findings are important because differences in nucleation and growth rates and particle sizes will impact the number of available reactive sites and the reactivity of newly formed particles toward aqueous contaminants.

Sorption of sodium hydroxide by type I collagen and bovine corneas.

PubMed

Whikehart, D R; Edwards, W C; Pfister, R R

1991-01-01

There are no quantitative studies on the uptake of alkali into corneal tissues. To study this phenomenon, both type I collagen and bovine corneas were incubated in sodium hydroxide (NaOH) under varying conditions for periods up to 27.5 h. The sorption (absorption or adsorption) of the alkali to protein and tissue was measured as the quantity of NaOH no longer available for titration to neutrality with hydrochloric acid. Sorption was found to be dependent on the concentration of NaOH (0.01-1 N) but independent of the incubation temperature (4-35 degrees C). In whole cornea, sorption of 1 N NaOH began immediately and increased with time up to 6 h. After 6 h, sorption decreased, together with the observed degradation and solubilization of the tissue. Stripping of the corneal endothelium alone or of the endothelium and epithelium increased sorption in a similar manner when compared to whole corneas for periods up to 4 h. These observations are compatible with ionic and nonionic bonding of hydroxide ions to collagen (including that of the cornea) and the subsequent release of hydroxide ions during hydrolysis of the protein itself. Indirect evidence also suggests the inclusion of quantities of unbound hydroxide ions in hydrated gels of glycosaminoglycans. It is proposed that in a chemical burn of the cornea, alkali is both stored in the tissue (by sorption) and reacted with it (by hydrolysis), without any net consumption of alkali taking place.

Sedimentation of iron deposits in Nagahama Bay, Satsuma Iwo-jima Island:Precipitation behavior of colloidal particle

NASA Astrophysics Data System (ADS)

Harada, T.; Kiyokawa, S.; Ikehara, M.

2016-12-01

Satsuma Iwo-Jima Island, with volcanic activities, is located about 40km south of Kyushu Island, Japan. This island is one of the best places to observe a shallow water hydrothermal system. Nagahama Bay, in the south of Satsuma Iwo-Jima Island, is partly separated from open sea. The seawater appears dark reddish brown color due to colloidal iron hydroxide by the mixing of volcanic fluids (pH=5.5, 50-60 degree Celsius) and oceanic water (Ninomiya & kiyokawa, 2009; Kiyokawa et al., 2012; Ueshiba & kiyokawa, 2012). Very high deposition rate (33 cm per year) of iron-rich sediments was observed in the bay (Kiyokawa et al., 2012). However, precipitation behavior of colloidal iron hydroxide has not been clarified. In this study, I report the results of analysis of deposition experiments of the colloidal particles at the Nagahama bay. Since the size of the colloidal particles is 1nm 1μm, single particle cannot be precipitated. This arise from precipitation of the particles in the viscous fluid is according to the Stokes' law. Colloidal iron hydroxide has the property of having the electric charges on the surface. The charge on the colloids is affected by pH of its surrounding seawater and can become more positively or negatively charged due to the gain or loss, respectively, of protons (H+) in the seawater. This property affects the stability of the colloidal dispersion. FE-SEM observation shows that the suspended particles consist of colloidal iron hydroxide (about 0.2μm), on the other hand, the iron-rich sediments are composed of bigger one (>1 μm). This indicates the colloidal iron hydroxide is precipitated by flocculation. We examined the precipitation amount of colloidal iron hydroxide under the various pH environments. The precipitation amount of pH=7.8 seawater 10% higher than that of pH=7.2. This result is roughly follows the theoretical value.

The hypocholesterolemic effect of an antacid containing aluminum hydroxide.

PubMed

Sperber, A D; Henkin, Y; Zuili, I; Bearman, J E; Shany, S

1991-12-01

To evaluate the efficacy, safety, and hypocholesterolemic effect of an aluminum hydroxide-containing antacid in hypercholesterolemic individuals. A prospective, randomized, double-masked, placebo-controlled phase of 2 months' duration, followed by an open-design treatment phase of 2 months' duration and a washout phase of 2 months' duration. Family practice clinics of two rural communities (kibbutzim) in Israel. Fifty-six men and women with hypercholesterolemia (type IIa or IIb). Fifty individuals completed the study. After 2 months of dietary modification (low-fat, low-cholesterol diet), the participants were randomized into two matched groups. Group 1 (28 participants) was treated for 2 months with a chewable antacid tablet containing simethicone, magnesium hydroxide, and 113 mg of aluminum hydroxide per tablet, at a dose of two tablets four times daily. Group 2 (22 participants) was given a similar number of placebo tablets for 2 months. During the following 2 months, both groups received the antacid at the above dose. Lipoprotein levels were evaluated at baseline and every 2 months thereafter for 6 months. Compared with pretreatment levels, Group 1 experienced a decrease in low-density lipoprotein cholesterol (LDL-C) of 9.8% after 2 months (p less than 0.001) and 18.5% after 4 months (p less than 0.001). Compared with Group 2, the decrease in LDL-C in Group 1 was 6.2% at the end of the 2-month double-masked, placebo phase. Although the high-density lipoprotein cholesterol (HDL-C) was also reduced in Group 1 at the end of 4 months of therapy (10.2%), the HDL-C/LDL-C ratio increased by 13% during the same interval (p less than 0.05). The treatment was well tolerated, with minimal side effects. An aluminum hydroxide-containing antacid reduces LDL-C in hypercholesterolemic individuals. Although HDL-C was also reduced to a lesser extent, the overall atherogenic index was improved. Further studies should be conducted to evaluate the long-term safety and efficacy of antacids containing aluminum hydroxide in hypercholesterolemic patients.

Influence of manganese incorporation on structure, surface and As(III)/As(V) removal capacity of iron oxy-hydroxides

NASA Astrophysics Data System (ADS)

Tresintsi, Sofia; Simeonidis, Konstantinos; Mitrakas, Manassis

2013-04-01

Iron oxy-hydroxides are well defined As(V) adsorbents dominating in water treatment market. The main drawback of these adsorbents, as well as of all commercial one, is their significantly low adsorption capacity for As(III). A breakthrough for improving As(III) adsorption of iron oxy-hydroxides may come by the MnO2incorporation. However, MnO2 decreases the total arsenic capacity proportionally to its percentage since its efficiency for As(V) is much lower than that of an iron oxy-hydroxide. It is concluded that an ideal adsorbent capable for high and simultaneous As(III) and As(V) removal should be consisted of a binary Fe(III)-Mn(IV) oxy-hydroxide both efficient for As(III) oxidation, due to Mn(IV) presence, and capture of As(V) due to a high positively surface charge density. This work studies the optimum parameters at the synthesis of single Fe and binary Fe/Mn oxy-hydroxides in a continuous flow kilogram-scale production reactor through the precipitation of FeSO4 in the pH range 3-12, under intense oxidative conditions using H2O2/KMnO4, that maximize arsenic adsorption. The evaluation of their efficiency was based on its As(III) and As(V) adsorption capacity (Q10-index) at equilibrium concentration equal to drinking water regulation limit (Ce= 10 μg/L) in NSF challenge water. The pH of synthesis was found to decisively affect, the structure, surface configuration and Q10-index. As a result, both single Fe and binary Fe/Mn oxy-hydroxides prepared at pH 4, which consist of schwertmannite and Mn(IV)-feroxyhyte respectively, were qualified according to their highest Q10-index of 13±0.5 μg As(V)/ mg for a residual arsenic concentration of 10 μg/L at an equilibrium pH 7. The high surface charge and the activation of an ion-exchange mechanism between SO42- adsorbed in the Stern layer and arsenate ions were found to significantly contribute to the increased adsorption capacity. The Q10-index for As(III) of Fe/Mn adsorbent at equilibrium pH 7 was 6.7 μg/mg, which is 3.5 times greater of that for single Fe one (1.9 μg/mg), although it is significantly lower of the respective for As(V). However, Fe/Mn oxy-hydroxide present almost equal adsorption capacity for both arsenic species in the pH range 7.5-8. The As(III) adsorption capacity of Fe/Mn oxy-hydroxides is positively affected by the Mn content and the redox potential values at equilibrium pH 6-7. The corresponding Q10-index values observed in rapid scale column tests were in agreement with those of batch experiments, illustrating the improved efficiency of the qualified adsorbent compared to the common commercial arsenic adsorbents. Acknowledgement This work was supported by the European Commission FP7/Research for SMEs "AquAsZero", Project No: 232241.

SUMMARY REVIEW OF THE HEALTH EFFECTS ASSOCIATED WITH SODIUM HYDROXIDE: HEALTH ISSUE ASSESSMENT

EPA Science Inventory

Sodium hydroxide (NaOH) is produced in large quantities in the U.S. and the aerosol may be rebased into the atmosphere. Inhalation of aerosolized NaOH can cause damage to the upper respiratory tract and to the lungs. Rats exposed to a 40% NaOH aerosol in a chronic study showed br...

Effect of calcium hydroxide application to feedlot pen surface material on ammonia, odor, and greenhouse gas emissions

USDA-ARS?s Scientific Manuscript database

Calcium hydroxide (lime) is used to reduce microorganisms and odors in human biosolids, animal and poultry manures, and abattoir wastes. In the cattle industry, lime has been used as a disinfectant and is spread on the pen surface to control infections such as diarrhea and foot rot. The increase in ...

Fabrication of nickel hydroxide electrodes with open-ended hexagonal nanotube arrays for high capacitance supercapacitors.

PubMed

Wu, Mao-Sung; Huang, Kuo-Chih

2011-11-28

A nickel hydroxide electrode with open-ended hexagonal nanotube arrays, prepared by hydrolysis of nickel chloride in the presence of hexagonal ZnO nanorods, shows a very high capacitance of 1328 F g(-1) at a discharge current density of 1 A g(-1) due to the significantly improved ion transport.

Acceptor-type hydroxide graphite intercalation compounds electrochemically formed in high ionic strength solutions.

PubMed

Miyazaki, Kohei; Iizuka, Asuka; Mikata, Koji; Fukutsuka, Tomokazu; Abe, Takeshi

2017-09-05

The intercalation of hydroxide ions (OH - ) into graphite formed graphite intercalation compounds (GICs) in high ionic strength solutions. GICs of solvated OH - anions with two water molecules (OH - ·2H 2 O) in alkaline aqueous solutions and GICs of only OH - anions in a molten NaOH-KOH salt solution were electrochemically synthesized.

Ion Association versus Ion Interaction Models in Examining Electrolyte Solutions: Application to Calcium Hydroxide Solubility Equilibrium

ERIC Educational Resources Information Center

Menéndez, M. Isabel; Borge, Javier

2014-01-01

The heterogeneous equilibrium of the solubility of calcium hydroxide in water is used to predict both its solubility product from solubility and solubility values from solubility product when inert salts, in any concentration, are present. Accepting the necessity of including activity coefficients to treat the saturated solution of calcium…

Highly Conductive Anion Exchange Block Copolymers

DTIC Science & Technology

We are developing a comprehensive fundamental understanding of the interplay between transport and morphology in newly synthesized hydroxide...conducting block copolymers. We are synthesizing hydroxide conducting block copolymers of various (1) morphology types, (2) ionic concentrations, and (3...ionic domain sizes. We are carefully characterizing the morphology and transport properties using both conventional and new advanced in situ techniques

Photocatalytic organic transformation by layered double hydroxides: highly efficient and selective oxidation of primary aromatic amines to their imines under ambient aerobic conditions.

PubMed

Yang, Xiu-Jie; Chen, Bin; Li, Xu-Bing; Zheng, Li-Qiang; Wu, Li-Zhu; Tung, Chen-Ho

2014-06-25

We report the first application of layered double hydroxide as a photocatalyst in the transformation of primary aromatic amines to their corresponding imines with high efficiency and selectivity by using oxygen in an air atmosphere as a terminal oxidant under light irradiation.

Multifunctional cerium-based nanomaterials and methods for producing the same

DOEpatents

O'Keefe, Matthew J.; Castano Londono, Carlos E.; Fahrenholtz, William G.

2018-01-09

Embodiments relate to a cerium-containing nano-coating composition, the composition including an amorphous matrix including one or more of cerium oxide, cerium hydroxide, and cerium phosphate; and crystalline regions including one or more of crystalline cerium oxide, crystalline cerium hydroxide, and crystalline cerium phosphate. The diameter of each crystalline region is less than about 50 nanometers.

Layered gadolinium hydroxides for low-temperature magnetic cooling.

PubMed

Abellán, Gonzalo; Espallargas, Guillermo Mínguez; Lorusso, Giulia; Evangelisti, Marco; Coronado, Eugenio

2015-09-28

Layered gadolinium hydroxides have revealed to be excellent candidates for cryogenic magnetic refrigeration. These materials behave as pure 2D magnetic systems with a Heisenberg-Ising critical crossover, induced by dipolar interactions. This 2D character and the possibility offered by these materials to be delaminated open the possibility of rapid heat dissipation upon substrate deposition.

THE COMPARISON OF SEVERAL STANDARD MATERIALS AND TECHNIQUES FOR THE WARREN-AVERBACH DETERMINATION OF MICRO-STRUCTURE CHARACTERISTICS OF CALCIUM HYDROXIDE SORBENT MATERIALS

EPA Science Inventory

The paper gives results of a comparison of several standard materials and techniques for the Warren-Averbach determination of microstructure characteristics of calcium hydroxide--Ca(OH)2--sorbent materials. The comparison is part of an investigation of the injection of dry Ca(OH)...

21 CFR 184.1631 - Potassium hydroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... thickener as defined in § 170.3(o)(28) of this chapter. (2) The ingredient is used in food at levels not to... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium hydroxide. 184.1631 Section 184.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR...

Aluminum hydroxide coating thickness measurements and brushing tests on K West Basin fuel elements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitner, A.L.

1998-09-11

Aluminum hydroxide coating thicknesses were measured on fuel elements stored in aluminum canisters in K West Basin using specially developed eddy current probes . The results were used to estimate coating inventories for MCO fuel,loading. Brushing tests successfully demonstrated the ability to remove the coating if deemed necessary prior to MCO loading.

Efficacy of copper borax preservative against wood decay

Treesearch

William Abbott; Bessie Woodward; Michael West

2001-01-01

In this study, a wood preservative containing active ingredients of 43.5% borax and 3.1% copper hydroxide was evaluated in soil-block tests in accordance with AWPA E10. Results suggested thatthe copper hydroxide was not contributing to fungal toxicity at preservative threshold levels. Thresholds determined for this preservative were very close to those previously...

Three-dimensionally networked graphene hydroxide with giant pores and its application in supercapacitors

PubMed Central

Lee, Dongwook; Seo, Jiwon

2014-01-01

The three-dimensionally networked and layered structure of graphene hydroxide (GH) was investigated. After lengthy immersion in a NaOH solution, most of the epoxy groups in the graphene oxide were destroyed, and more hydroxyl groups were generated, transforming the graphene oxide into graphene hydroxide. Additionally, benzoic acid groups were formed, and the ether groups link the neighboring layers, creating a near-3D structure in the GH. To utilize these unique structural features, electrodes with large pores for use in supercapacitors were fabricated using thermal reduction in vacuum. The reduced GH maintained its layered structure and developed a lot of large of pores between/inside the layers. The GH electrodes exhibited high gravimetric as well as high volumetric capacitance. PMID:25492227

Three-dimensionally networked graphene hydroxide with giant pores and its application in supercapacitors

NASA Astrophysics Data System (ADS)

Lee, Dongwook; Seo, Jiwon

2014-12-01

The three-dimensionally networked and layered structure of graphene hydroxide (GH) was investigated. After lengthy immersion in a NaOH solution, most of the epoxy groups in the graphene oxide were destroyed, and more hydroxyl groups were generated, transforming the graphene oxide into graphene hydroxide. Additionally, benzoic acid groups were formed, and the ether groups link the neighboring layers, creating a near-3D structure in the GH. To utilize these unique structural features, electrodes with large pores for use in supercapacitors were fabricated using thermal reduction in vacuum. The reduced GH maintained its layered structure and developed a lot of large of pores between/inside the layers. The GH electrodes exhibited high gravimetric as well as high volumetric capacitance.

Three-dimensionally networked graphene hydroxide with giant pores and its application in supercapacitors.

PubMed

Lee, Dongwook; Seo, Jiwon

2014-12-10

The three-dimensionally networked and layered structure of graphene hydroxide (GH) was investigated. After lengthy immersion in a NaOH solution, most of the epoxy groups in the graphene oxide were destroyed, and more hydroxyl groups were generated, transforming the graphene oxide into graphene hydroxide. Additionally, benzoic acid groups were formed, and the ether groups link the neighboring layers, creating a near-3D structure in the GH. To utilize these unique structural features, electrodes with large pores for use in supercapacitors were fabricated using thermal reduction in vacuum. The reduced GH maintained its layered structure and developed a lot of large of pores between/inside the layers. The GH electrodes exhibited high gravimetric as well as high volumetric capacitance.

An advanced Ni-Fe layered double hydroxide electrocatalyst for water oxidation.

PubMed

Gong, Ming; Li, Yanguang; Wang, Hailiang; Liang, Yongye; Wu, Justin Z; Zhou, Jigang; Wang, Jian; Regier, Tom; Wei, Fei; Dai, Hongjie

2013-06-12

Highly active, durable, and cost-effective electrocatalysts for water oxidation to evolve oxygen gas hold a key to a range of renewable energy solutions, including water-splitting and rechargeable metal-air batteries. Here, we report the synthesis of ultrathin nickel-iron layered double hydroxide (NiFe-LDH) nanoplates on mildly oxidized multiwalled carbon nanotubes (CNTs). Incorporation of Fe into the nickel hydroxide induced the formation of NiFe-LDH. The crystalline NiFe-LDH phase in nanoplate form is found to be highly active for oxygen evolution reaction in alkaline solutions. For NiFe-LDH grown on a network of CNTs, the resulting NiFe-LDH/CNT complex exhibits higher electrocatalytic activity and stability for oxygen evolution than commercial precious metal Ir catalysts.

Root End Generation: An Unsung Characteristic Property of MTA-A Case Report

PubMed Central

Dixit, Seema; Dixit, Ashutosh; Kumar, Pravin; Arora, Saurabh

2014-01-01

Management of immature teeth with necrotic pulp and periapical lesion has long presented a challenge. The treatment of choice for such teeth is apexification, which is induction of apical closure to produce more favorable conditions for conventional canal obturation. Traditionally, calcium hydroxide has been used for the apexification of immature permanent teeth, however, Mineral Trioxide Aggregate (MTA) holds significant promise not only as an alternative to multiple treatment visits with calcium hydroxide but also having the potential to induce root end development, eventually forming a completed root apex. This case report presents a successful healing and apexification with the use of calcium hydroxide and MTA. A 5-year follow-up revealed root development with MTA. PMID:24596800

Molecular dynamics in aluminum layered double hydroxides as studied by 1H T1ρ NMR measurements

NASA Astrophysics Data System (ADS)

Vyalikh, Anastasia; Wang, De-Yi; Wagenknecht, Udo; Heinrich, Gert; Scheler, Ulrich

2011-06-01

Proton dynamics in pristine and organically-modified layered double hydroxide has been studied by 1H T1ρ. Inverse Laplace transform with spectral resolution results in a correlation of T1ρ and chemical shift. In LDH two contributions are resolved. They are assigned to the metal hydroxides, forming the LDH sheets (4-8 ms), and mobile interlayer water (2 ms). Apparent T1ρ values of OH-protons in surfactant-modified LDH are different in dodecylbenzenesulfonate- (SDBS) and sodium octasulfonate- (C8) modified LDH. This difference is explained by the presence of water in LDH-SDBS. The effects of spin diffusion have been studied by performing 2D 1H RFDR in the LDH-SDBS.

Differential potentiometric titration: development of a methodology for determining the point of zero charge of metal (hydr)oxides by one titration curve.

PubMed

Bourikas, Kyriakos; Kordulis, Christos; Lycourghiotis, Alexis

2005-06-01

A new methodology is presented, called differential potentiometric titration (DPT), which allows the determination of the point of zero charge (pzc) of metal (hydr)oxides using only one potentiometric curve. By performing extensive simulations of potentiometric titrations for various model (hydr)oxides, we found that an inflection point in a H+(cons,surf) versus pH potentiometric curve (H+(cons,surf): hydrogen ions consumed on the surface of the (hydr)oxide) and a peak in the corresponding differential curve, dH+(cons,surf)/dpH versus pH, appear at a pH equal to the pzc assumed for a model (hydr)oxide. This distinguishable peak appears at the same position irrespective of the surface ionization and the interfacial model adopted as well as the assumed ionic strength. It was found that the aforementioned peak also appears in the high-resolution differential potentiometric curves experimentally determined for four oxides (SiO2, TiO2, gamma-Al2O3, and MgO) that are widely used in various environmental and other technological applications. The application of DPT to the above-mentioned oxides provided practically the same pzc values as the corresponding ones achieved by using four different techniques as well as the corresponding isoelectric point (iep) values determined by microelectrophoresis. Differences between the pzc and iep values determined using various techniques in the case of MgO were attributed to the increasing dissolution of this oxide as pH decreases and the adsorption of cations (Mg2+, Na+) on the MgO/electrolytic solution interface.

Rational design of interfacial properties of ferric (hydr)oxide nanoparticles by adsorption of fatty acids from aqueous solutions.

PubMed

Ponnurangam, Sathish; Chernyshova, Irina V; Somasundaran, Ponisseril

2012-07-24

Notwithstanding the great practical importance, still open are the questions how, why, and to what extent the size, morphology, and surface charge of metal (hydr)oxide nanoparticles (NPs) affect the adsorption form, adsorption strength, surface density, and packing order of organic (bio)molecules containing carboxylic groups. In this article, we conclusively answer these questions for a model system of ferric (hydr)oxide NPs and demonstrate applicability of the established relationships to manipulating their hydrophobicity and dispersibility. Employing in situ Fourier transform infrared (FTIR) spectroscopy and adsorption isotherm measurements, we study the interaction of 150, 38, and 9 nm hematite (α-Fe(2)O(3)) and ∼4 nm 2-line ferrihydrite with sodium laurate (dodecanoate) in water. We discover that, independent of morphology, an increase in size of the ferric (hydr)oxide NPs significantly improves their adsorption capacity and affinity toward fatty acids. This effect favors the formation of bilayers, which in turn promotes dispersibility of the larger NPs in water. At the same time, the local order in self-assembled monolayer (SAM) strongly depends on the morphological compatibility of the NP facets with the geometry-driven well-packed arrangements of the hydrocarbon chains as well as on the ratio of the chemisorbed to the physically adsorbed carboxylate groups. Surprisingly, the geometrical constraints can be removed, and adsorption capacity can be increased by negatively polarizing the NPs due to promotion of the outer-sphere complexes of the fatty acid. We interpret these findings and discuss their implications for the nanotechnological applications of surface-functionalized metal (hydr)oxide NPs.

Imidazolium-Based Polymeric Materials as Alkaline Anion-Exchange Fuel Cell Membranes

NASA Technical Reports Server (NTRS)

Narayan, Sri R.; Yen, Shiao-Ping S.; Reddy, Prakash V.; Nair, Nanditha

2012-01-01

Polymer electrolyte membranes that conduct hydroxide ions have potential use in fuel cells. A variety of polystyrene-based quaternary ammonium hydroxides have been reported as anion exchange fuel cell membranes. However, the hydrolytic stability and conductivity of the commercially available membranes are not adequate to meet the requirements of fuel cell applications. When compared with commercially available membranes, polystyrene-imidazolium alkaline membrane electrolytes are more stable and more highly conducting. At the time of this reporting, this has been the first such usage for imidazolium-based polymeric materials for fuel cells. Imidazolium salts are known to be electrochemically stable over wide potential ranges. By controlling the relative ratio of imidazolium groups in polystyrene-imidazolium salts, their physiochemical properties could be modulated. Alkaline anion exchange membranes based on polystyrene-imidazolium hydroxide materials have been developed. The first step was to synthesize the poly(styrene-co-(1-((4-vinyl)methyl)-3- methylimidazolium) chloride through a free-radical polymerization. Casting of this material followed by in situ treatment of the membranes with sodium hydroxide solutions provided the corresponding hydroxide salts. Various ratios of the monomers 4-chloromoethylvinylbenzine (CMVB) and vinylbenzine (VB) provided various compositions of the polymer. The preferred material, due to the relative ease of casting the film, and its relatively low hygroscopic nature, was a 2:1 ratio of CMVB to VB. Testing confirmed that at room temperature, the new membranes outperformed commercially available membranes by a large margin. With fuel cells now in use at NASA and in transportation, and with defense potential, any improvement to fuel cell efficiency is a significant development.

Analysis of Aloe vera cytotoxicity and genotoxicity associated with endodontic medication and laser photobiomodulation.

PubMed

Carvalho, Nayane Chagas; Guedes, Simone Alves Garcez; Albuquerque-Júnior, Ricardo Luiz Cavalcanti; de Albuquerque, Diana Santana; de Souza Araújo, Adriano Antunes; Paranhos, Luiz Renato; Camargo, Samira Esteves Afonso; Ribeiro, Maria Amália Gonzaga

2018-01-01

This study aims to evaluate, in vitro, the effect of Aloe vera associated with endodontic medication, with or without laser photobiomodulation (FTL) irradiation in FP6 human pulp fibroblasts. The materials were divided into eight groups: CTR - control; CL - FTL alone; AA - Aloe vera with distilled water; AL - Aloe vera with distilled water and FTL; HA - calcium hydroxide P.A. with distilled water; HL - calcium hydroxide P.A. with distilled water and FTL; HAA - calcium hydroxide P.A. with Aloe vera and distilled water; HAL - calcium hydroxide P.A. with Aloe vera, distilled water, and FTL. The cytotoxicity was evaluated by MTT assay at 24, 48, and 72h and the genotoxicity by micronucleus test assay. This study was performed in triplicate. Data obtained in both tests were statistically analyzed by ANOVA and Tukey's tests (p≤0.05). Group AA presented high genotoxicity and low cytotoxicity. After 24, 48, and 72h, the group HAA significantly reduced the cell viability. Interaction with FTL showed slightly increase cell viability after 24 and 48h in groups CL and HL (p<0.001), despite the high genotoxicity in group CL and low genotoxicity in group HL. Group AL showed higher cell survival rate at 72h (p<0.05) and high genotoxicity (p<0.001). It was concluded that Aloe vera allowed higher cell viability in human pulp fibroblasts in the presence of calcium hydroxide or with FTL separately, but genotoxicity increased in these associations. Copyright © 2017 Elsevier B.V. All rights reserved.

Intercalation of paracetamol into the hydrotalcite-like host

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kovanda, Frantisek, E-mail: Frantisek.Kovanda@vscht.cz; Maryskova, Zuzana; Kovar, Petr

2011-12-15

Hydrotalcite-like compounds are often used as host structures for intercalation of various anionic species. The product intercalated with the nonionic, water-soluble pharmaceuticals paracetamol, N-(4-hydroxyphenyl)acetamide, was prepared by rehydration of the Mg-Al mixed oxide obtained by calcination of hydrotalcite-like precursor at 500 Degree-Sign C. The successful intercalation of paracetamol molecules into the interlayer space was confirmed by powder X-ray diffraction and infrared spectroscopy measurements. Molecular simulations showed that the phenolic hydroxyl groups of paracetamol interact with hydroxide sheets of the host via the hydroxyl groups of the positively charged sites of Al-containing octahedra; the interlayer water molecules are located mostly nearmore » the hydroxide sheets. The arrangement of paracetamol molecules in the interlayer is rather disordered and interactions between neighboring molecules cause their tilting towards the hydroxide sheets. Dissolution tests in various media showed slower release of paracetamol intercalated in the hydrotalcite-like host in comparison with tablets containing the powdered pharmaceuticals. - Graphical abstract: Molecular simulations showed disordered arrangement of paracetamol molecules in the interlayer; most of the interlayer water molecules are located near the hydroxide sheets. Black-Small-Square Highlights: Black-Right-Pointing-Pointer Paracetamol was intercalated in Mg-Al hydrotalcite-like host by rehydration/reconstruction procedure. Black-Right-Pointing-Pointer Paracetamol phenolic groups interact with positively charged sites in hydroxide sheets. Black-Right-Pointing-Pointer Molecular simulations showed disordered arrangement of guest molecules in the interlayer. Black-Right-Pointing-Pointer Slower release of paracetamol intercalated in the hydrotalcite-like host was observed.« less

Layered assembly of graphene oxide and Co-Al layered double hydroxide nanosheets as electrode materials for supercapacitors.

PubMed

Wang, Lei; Wang, Dong; Dong, Xin Yi; Zhang, Zhi Jun; Pei, Xian Feng; Chen, Xin Jiang; Chen, Biao; Jin, Jian

2011-03-28

An innovative strategy of fabricating electrode material by layered assembling two kinds of one-atom-thick sheets, carboxylated graphene oxide (GO) and Co-Al layered double hydroxide nanosheet (Co-Al LDH-NS) for the application as a pseudocapacitor is reported. The Co-Al LDH-NS/GO composite exhibits good energy storage properties.

Carbon Dioxide Absorbers: An Engaging Experiment for the General Chemistry Laboratory

ERIC Educational Resources Information Center

Ticich, Thomas M.

2011-01-01

A simple and direct method for measuring the absorption of carbon dioxide by two different substances is described. Lithium hydroxide has been used for decades to remove the gas from enclosed living spaces, such as spacecraft and submarines. The ratio of the mass of carbon dioxide absorbed to the mass of lithium hydroxide used obtained from this…

Exploring Alkaline Stable Organic Cations for Polymer Hydroxide Exchange Membranes

DTIC Science & Technology

2015-04-29

1   1.1.2   Proton exchange membrane fuel cells ( PEMFCs ) ......................... 3   1.1.3   Alkaline fuel cells (AFCs...160   xi LIST OF FIGURES Figure 1.1:   Schematic diagram of a PEMFC ...according to the type of electrolyte they use. Nowadays, there are six major types of fuel cells: proton-exchange membrane fuel cells ( PEMFCs ), hydroxide

Aqueous alkali metal hydroxide insoluble cellulose ether membrane

NASA Technical Reports Server (NTRS)

Hoyt, H. E.; Pfluger, H. L. (Inventor)

1969-01-01

A membrane that is insoluble in an aqueous alkali metal hydroxide medium is described. The membrane is a resin which is a water-soluble C2-C4 hydroxyalkyl cellulose ether polymer and an insolubilizing agent for controlled water sorption, a dialytic and electrodialytic membrane. It is particularly useful as a separator between electrodes or plates in an alkaline storage battery.

PROCESS FOR REMOVING ALUMINUM COATINGS

DOEpatents

Flox, J.

1959-07-01

A process is presented for removing aluminum jackets or cans from uranium slugs. This is accomplished by immersing the aluminum coated uranium slugs in an aqueous solution of 9 to 20% sodium hydroxide and 35 to 12% sodium nitrate to selectively dissolve the aluminum coating, the amount of solution being such as to obtain a molar ratio of sodium hydroxide to aluminum of at least

Suitable alkaline for graphene peeling grown on metallic catalysts using chemical vapor deposition

NASA Astrophysics Data System (ADS)

Karamat, S.; Sonuşen, S.; Çelik, Ü.; Uysallı, Y.; Oral, A.

2016-04-01

In chemical vapor deposition, the higher growth temperature roughens the surface of the metal catalyst and a delicate method is necessary for the transfer of graphene from metal catalyst to the desired substrates. In this work, we grow graphene on Pt and Cu foil via ambient pressure chemical vapor deposition (AP-CVD) method and further alkaline water electrolysis was used to peel off graphene from the metallic catalyst. We used different electrolytes i.e., sodium hydroxide (NaOH), potassium hydroxide (KOH), lithium hydroxide (LiOH) and barium hydroxide Ba(OH)2 for electrolysis, hydrogen bubbles evolved at the Pt cathode (graphene/Pt/PMMA stack) and as a result graphene layer peeled off from the substrate without damage. The peeling time for KOH and LiOH was ∼6 min and for NaOH and Ba(OH)2 it was ∼15 min. KOH and LiOH peeled off graphene very efficiently as compared to NaOH and Ba(OH)2 from the Pt electrode. In case of copper, the peeling time is ∼3-5 min. Different characterizations like optical microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy were done to analyze the as grown and transferred graphene samples.

Three dimensional metal/N-doped nanoplate carbon catalysts for oxygen reduction, the reason for using a layered nanoreactor.

PubMed

Yeganeh Ghotbi, Mohammad; Javanmard, Arash; Soleimani, Hassan

2018-02-21

A layered nanoreactor (zinc hydroxide gallate/nitrate nanohybrid) has been designed as a nano-vessel to confine the gallate/nitrate reaction inside zinc hydroxide layers for production of metal/nitrogen-doped carbon catalysts. Metals (Fe 2+ , Co 2+ and Ni 2+ ) doped and bare zinc hydroxide nitrates (ZHN) were synthesized as the α-phase hydroxide hosts. By an incomplete ion-exchange process, nitrate anions between the layers of the hosts were then partially replaced by the gallate anions to produce the layered nanoreactors. Under heat-treatment, the reaction between the remaining un-exchanged nitrate anions and the organic moiety inside the basal spacing of each nanohybrid plate resulted in obtaining highly porous 3D metal/nitrogen-doped carbon nanosheets. These catalysts were then used as extremely efficient electrocatalysts for catalyzing oxygen reduction reaction (ORR). This study is intended to show the way to get maximum electrocatalytic activity of the metal/N-doped carbon catalysts toward the ORR. This exceptionally high ORR performance originates from the increased available surface, the best pore size range and the uniform distribution of the active sites in the produced catalysts, all provided by the use of new idea of the layered nanoreactor.

Comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain and aloe vera (all in gel formulation), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis: An in vitro study.

PubMed

Bhardwaj, Anuj; Ballal, Suma; Velmurugan, Natanasabapathy

2012-07-01

A comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain, and aloe vera (all in gel formulations), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis-an in vitro study. The antimicrobial efficacy was assessed in vitro using dentin shavings collected at 2 depths of 200 and 400 μm. The total colony forming units at the end of 1, 3, and 5 days were assessed. The overall percentage inhibition of bacterial growth (200 and 400 μm depth) was 100% with chlorhexidine gel. This was followed by M. citrifolia gel (86.02%), which showed better antimicrobial efficacy as compared with aloe vera gel (78.9%), papain gel (67.3%), and calcium hydroxide (64.3%). There was no statistical difference between data at 200 and 400 μm depth. Chlorhexidine gel showed the maximum antimicrobial activity against E. faecalis, whereas calcium hydroxide showed the least. Among the natural intracanal medicaments, M. citrifolia gel consistently exhibited good inhibition up to the 5(th) day followed by aloe vera gel and papain gel.

Flare-ups incidence and severity after using calcium hydroxide as intracanal dressing.

PubMed

Ghoddusi, Jamileh; Javidi, Maryam; Zarrabi, Mohammad Hasan; Bagheri, Hossein

2006-01-01

Acute pain and swelling following endodontic treatment are a challenge for both the patient and the dentist. According to previous studies, the incidence of flare-ups increases after endodontic treatment of teeth with necrotic pulps. Calcium hydroxide is currently used as a multi-purpose drug in root canal therapy. The aim of this study was to evaluate the incidence and severity of flare-ups after treatment of pulpless teeth using calcium hydroxide as an intracanal dressing. Sixty patients with single-root necrotic teeth participated in this study. These patients were randomly divided into three groups of 20. The patients were treated in Group A in a single-visit approach, in group B with a two-visit approach without any intracanal dressing and group C with a two-visit approach using calcium hydroxide as an intracanal dressing for one week. All of the patients were followed for 72 hours after each treatment session. The information about the incidence and severity of pain and swelling was recorded in tables, using a modified Visual Analogue Scale for pain severity measurement and a scale with four degrees for measuring the severity of swelling. The data were analyzed by chi-square test and GENMODE procedure.

NiFe (Oxy) Hydroxides Derived from NiFe Disulfides as an Efficient Oxygen Evolution Catalyst for Rechargeable Zn-Air Batteries: The Effect of Surface S Residues.

PubMed

Wang, Tanyuan; Nam, Gyutae; Jin, Yue; Wang, Xingyu; Ren, Pengju; Kim, Min Gyu; Liang, Jiashun; Wen, Xiaodong; Jang, Haeseong; Han, Jiantao; Huang, Yunhui; Li, Qing; Cho, Jaephil

2018-05-21

A facile H 2 O 2 oxidation treatment to tune the properties of metal disulfides for oxygen evolution reaction (OER) activity enhancement is introduced. With this method, the degree of oxidation can be readily controlled and the effect of surface S residues in the resulted metal (oxy)hydroxides for the OER is revealed for the first time. The developed NiFe (oxy)hydroxide catalyst with residual S demonstrates an extraordinarily low OER overpotential of 190 mV at the current density of 10 mA cm -2 after coupling with carbon nanotubes, and outstanding performance in Zn-air battery tests. Theoretical calculation suggests that the surface S residues can significantly reduce the adsorption free energy difference between O* and OH* intermediates on the Fe sites, which should account for the high OER activity of NiFe (oxy)hydroxide catalysts. This work provides significant insight regarding the effect of surface heteroatom residues in OER electrocatalysis and offers a new strategy to design high-performance and cost-efficient OER catalysts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis, characterization, and efficacy of antituberculosis isoniazid zinc aluminum-layered double hydroxide based nanocomposites

PubMed Central

Saifullah, Bullo; El Zowalaty, Mohamed Ezzat; Arulselvan, Palanisamy; Fakurazi, Sharida; Webster, Thomas J; Geilich, Benjamin Mahler; Hussein, Mohd Zobir

2016-01-01

The chemotherapy for tuberculosis (TB) is complicated by its long-term treatment, its frequent drug dosing, and the adverse effects of anti-TB drugs. In this study, we have developed two nanocomposites (A and B) by intercalating the anti-TB drug isoniazid (INH) into Zn/Al-layered double hydroxides. The average size of the nanocomposites was found to bê164 nm. The efficacy of the Zn/Al-layered double hydroxides intercalated INH against Mycobacterium tuberculosis was increased by approximately three times more than free INH. The nanocomposites were also found to be active against Gram-positive and -negative bacteria. Compared to the free INH, the nanodelivery formulation was determined to be three times more biocompatible with human normal lung fibroblast MRC-5 cells and 3T3 fibroblast cells at a very high concentration of 50 µg/mL for up to 72 hours. The in vitro release of INH from the Zn/Al-layered double hydroxides was found to be sustained in human body-simulated buffer solutions of pH 4.8 and 7.4. This research is a step forward in making the TB chemotherapy patient friendly. PMID:27486322

A facile mechanochemical approach to synthesize Zn-Al layered double hydroxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qu, Jun, E-mail: forsjun@whut.edu.cn; He, Xiaoman; Chen, Min

2017-06-15

In this study, a mechanochemical route to synthesize Zn-Al layered double hydroxide (LDH) was introduced, in which Zn basic carbonate and Al hydroxide were first dry milled into an activated state and then agitated in water to obtain the final products. The as-prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetry (TG) and Scanning electron microscopy (SEM). The products possessed a high crystallinity of Zn–Al LDH phase without any other impurities, proving a facile and effective preparation of Zn–Al LDH by using non-heating mechanochemical approach. - Highlights: • A non-heating mechanochemical route to synthesize Zn-Almore » LDH. • The products possessed high crystalline Zn-Al LDH phase. • No emission of other impurities or wastewater.« less

Study of CO2 sorbents for extravehicular activity

NASA Technical Reports Server (NTRS)

Colombo, G. V.

1973-01-01

Portable life support equipment was studied for meeting the requirements of extravehicular activities. Previous studies indicate that the most promising method for performing the CO2 removal function removal function were metallic oxides and/or metallic hydroxides. Mgo, Ag2, and Zno metallic oxides and Mg(OH)2 and Zn(OH)2 metallic hydroxides were studied, by measuring sorption and regeneration properties of each material. The hydroxides of Mg and Zn were not regenerable and the zinc oxide compounds showed no stable form. A silver oxide formulation was developed which rapidly absorbs approximately 95% of its 0.19 Kg CO2 Kg oxide and has shown no sorption or structural degeneration through 22 regenerations. It is recommended that the basic formula be further developed and tested in large-scale beds under simulated conditions.

Ab initio calculations on the positive ions of the alkaline-earth oxides, fluorides, and hydroxides

NASA Technical Reports Server (NTRS)

Partridge, H.; Langhoff, S. R.; Bauschlicher, C. W., Jr.

1986-01-01

Theoretical dissociation energies are presented for the alkaline-earth fluoride, hydroxide, and oxide positive ions that are considered to be accurate to 0.1-0.2 eV. The r(e) for the positive ions are found to be consistently shorter than the corresponding neutrals by 0.07 + or -0.02 A. The bonding in the ground states is demonstrated to be of predominantly M + 2 X - character. The a 3 Pi and A 1 Pi are found to lie considerably above the X 1 Sigma + ground states of the alkaline-earth fluoride and hydroxide positive ions. The overall agreement of the theoretical ionization potentials with the available experimental appearance potentials is satisfactory; these values should represent the most accurate and consistent set available.

Synthesis of CoOOH nanorods and application as coating materials of nickel hydroxide for high temperature Ni-MH cells.

PubMed

Hu, W K; Gao, X P; Geng, M M; Gong, Z X; Noréus, D

2005-03-31

Studies on nanoscale materials have received great interest in both fundamental and applied aspects in recent years. In this letter, we report the synthesis of CoOOH nanorods and their possible applications as coating materials on nickel hydroxide for high-temperature nickel-metal hydride (Ni-MH) cells. The morphology and structure of CoOOH nanorods and coated nickel hydroxide particles are investigated by transmission electron microscopy, X-ray diffraction, and scanning electron microscopy, respectively. The electrochemical properties in the cylindrical AA size Ni-MH cells are evaluated. Our results show that the Ni-MH cells, where the positive electrodes are composed of such nanometer sized CoOOH coatings, have a higher capacity available and good performance at elevated temperatures of >50 degrees C.

Testicular cell population dynamics following palmitine hydroxide treatment in male dogs.

PubMed

Gupta, R S; Dixit, V P

1989-04-01

Palmitine hydroxide isolated from the roots of Berberis chitria administered orally to dogs 30 mg/kg per day for 60 days brings about a consistent impairment of primary and secondary spermatocytes and elongated spermatids (Stages IV-VIII). The primary and secondary spermatocytes were reduced by 60 and 68%, respectively, and the elongated spermatids were decreased by 58%. The number of spermatogonia and Sertoli cells remained unaltered. The production of immature and mature Leydig cells decreased by 66% and 27%, respectively. Protein, sialic acid and glycogen content and acid phosphatase activity of testes and epididymides were lowered to varying extents. Testicular cholesterol was elevated significantly. Weights of the testes and epididymides were significantly reduced. The antispermatogenic action of palmitine hydroxide may be mediated by disturbances in Leydig cell function.

Cadmium-Aluminum Layered Double Hydroxide Microspheres for Photocatalytic CO2 Reduction.

PubMed

Saliba, Daniel; Ezzeddine, Alaa; Sougrat, Rachid; Khashab, Niveen M; Hmadeh, Mohamad; Al-Ghoul, Mazen

2016-04-21

We report the synthesis of cadmium-aluminum layered double hydroxide (CdAl LDH) using the reaction-diffusion framework. As the hydroxide anions diffuse into an agar gel matrix containing the mixture of aluminum and cadmium salts at a given ratio, they react to give the LDH. The LDH self-assembles inside the pores of the gel matrix into a unique spherical-porous shaped microstructure. The internal and external morphologies of the particles are studied by electron microscopy and tomography revealing interconnected channels and a high surface area. This material is shown to exhibit a promising performance in the photoreduction of carbon dioxide using solar light. Moreover, the palladium-decorated version shows a significant improvement in its reduction potential at room temperature. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aluminum hydroxide, calcium carbonate and calcium acetate in chronic intermittent hemodialysis patients.

PubMed

Janssen, M J; van der Kuy, A; ter Wee, P M; van Boven, W P

1996-02-01

Prevention of secondary hyperparathyroidism in uremia necessitates correction of hyperphosphatemia and hypocalcemia. In order to avoid aluminum toxicity, calcium containing phosphate binders are used increasingly, instead of aluminium hydroxide. Recent studies have shown that calcium acetate has many characteristics of an ideal phosphate binder. It is, for instance, a more readily soluble salt compared with calcium carbonate. This advantage might, however, disappear if calcium carbonate is taken on an empty stomach, a few minutes before meals. We examined the efficacy of three different phosphate binding agents in a randomized prospective study of 53 patients on regular hemodialysis. Bicarbonate dialyses were performed with a dialysate calcium concentration of 1.75 mmol/l. After a three-week wash-out period, patients received either aluminum hydroxide (control group), calcium acetate, or calcium carbonate as their phosphate binder. Patients were instructed to take the calcium salts a few minutes before meals on an empty stomach, and aluminum hydroxide during meals. Serum calcium, phosphate, intact parathormone, and alkaline phosphatase levels were determined every month. Patient compliance was estimated every month by asking the patients which phosphate binder and what daily dose they had used. Aluminum hydroxide tended to be the most effective phosphate binder. The mean +/- SEM required daily dose of calcium acetate at 12 months was 5.04 +/- 0.60 g, corresponding to 10.1 +/- 1.20 tablets of 500 mg. Co-medication with aluminum hydroxide, however, was needed (1.29 +/- 0.54 g per day, corresponding to 2.6 +/- 1.08 tablets of 500 mg). The required daily calcium carbonate dose appeared to be 2.71 +/- 0.48 g, corresponding to 5.4 +/- 0.95 capsules of 500 mg, with an adjuvant daily aluminum hydroxide dose of 0.69 +/- 0.27 g, corresponding to 1.4 +/- 0.55 tablets of 500 mg (p = 0.0055). Thus, the mean daily doses of elemental calcium were comparable between the calcium acetate and calcium carbonate-treated patients (1.28 +/- 0.15 g versus 1.09 +/- 0.19 g; n.s.). The incidence of hypercalcemic episodes (albumin-corrected serum calcium levels above 2.80 mmol/l) in the calcium acetate-treated group was 18% versus 31% in the calcium carbonate-treated group (p < 0.005). None of the aluminum hydroxide-treated patients experienced hypercalcemic episodes. Mean serum concentrations of alkaline phosphatase, intact parathormone, and aluminum did not differ between the groups. In chronic intermittent hemodialysis patients, per gram administered elemental calcium phosphate binding with either calcium acetate or calcium carbonate is equivalent, provided that calcium carbonate is taken on an empty stomach a few minutes before meals. The number of capsules calcium carbonate, but also the total amount in grams, necessary to keep serum phosphate and intact parathormone levels into an acceptable range then is significantly less. This might improve patient compliance.

Zn- and Co-based layered double hydroxides: prediction of the a parameter from the fraction of trivalent cations and vice versa

PubMed Central

Richardson, Ian G.

2013-01-01

A recently proposed method to calculate the a parameter of the unit cell of layered double hydroxides from the fraction of trivalent cations is extended to Zn- and Co-based phases. It is shown to be useful as a sanity test for extant and future structure determinations and computer-simulation studies. PMID:23873067

Synergy and Diffusion with a Borax-Copper Hydroxide Groundline Preservative: 20 Year Update

Treesearch

Stan Lebow; Bessie Woodward; Bill Abbott; Mike West

2014-01-01

A groundline remedial treatment containing 3.1% copper hydroxide (2% elemental copper) and 40% sodium tetraborate decahydrate (borax) was applied to unseasoned pine posts prior to placement in a test site in southern Mississippi. The soundness of the posts was periodically evaluated using a push test. After 3.5, 6.5, 10, 15 and 20 years, sections were taken from two...

Polarographic Analysis of Primers

DTIC Science & Technology

1945-03-30

also in 0.5 M sodium acetate, ammonium acetate, aoetlc acid, sodium acetate plus acetic acid, and sodium tartrate plus tartaric &cid. In all these...potassium tartrate end potassium hydroxide (4 M pot as; ^ura hydroxide plus 2 11 potassium tartrate , the anodic sulfide tjave is well defined, but the...our experiments. Solutions of "synthetic" stibnite, formed by adding stoichinmetric amounts of potassium antimony! tartrate and sodium sulfide to

9 CFR 96.10 - Uncertified casings; transportation for disinfection; original shipping containers; disposition...

Code of Federal Regulations, 2011 CFR

2011-01-01

... hydroxide (Lye) prepared in a fresh solution in the proportion of not less than 1 pound avoirdupois of... in case any of the sodium hydroxide solution should come in contact with the body. (2) This solution...) Dissolve the salt in the proportion of 90 pounds of salt to 100 gallons of water. Add 23/4 gallons of C. P...

9 CFR 96.10 - Uncertified casings; transportation for disinfection; original shipping containers; disposition...

Code of Federal Regulations, 2014 CFR

2014-01-01

... hydroxide (Lye) prepared in a fresh solution in the proportion of not less than 1 pound avoirdupois of... in case any of the sodium hydroxide solution should come in contact with the body. (2) This solution...) Dissolve the salt in the proportion of 90 pounds of salt to 100 gallons of water. Add 23/4 gallons of C. P...

9 CFR 96.10 - Uncertified casings; transportation for disinfection; original shipping containers; disposition...

Code of Federal Regulations, 2013 CFR

2013-01-01

... hydroxide (Lye) prepared in a fresh solution in the proportion of not less than 1 pound avoirdupois of... in case any of the sodium hydroxide solution should come in contact with the body. (2) This solution...) Dissolve the salt in the proportion of 90 pounds of salt to 100 gallons of water. Add 23/4 gallons of C. P...

Method of producing hydrogen, and rendering a contaminated biomass inert

DOEpatents

Bingham, Dennis N [Idaho Falls, ID; Klingler, Kerry M [Idaho Falls, ID; Wilding, Bruce M [Idaho Falls, ID

2010-02-23

A method for rendering a contaminated biomass inert includes providing a first composition, providing a second composition, reacting the first and second compositions together to form an alkaline hydroxide, providing a contaminated biomass feedstock and reacting the alkaline hydroxide with the contaminated biomass feedstock to render the contaminated biomass feedstock inert and further producing hydrogen gas, and a byproduct that includes the first composition.

THE WEATHERING OF A SULFIDE OREBODY: SPECIATION AND FATE OF SOME POTENTIAL CONTAMINANTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Courtin-Nomade, Alexandra; Grosbois, Cecile; Marcus, Matthew A.

2010-07-16

Various potentially toxic trace elements such as As, Cu, Pb and Zn have been remobilized by the weathering of a sulfide orebody that was only partially mined at Leona Heights, California. As a result, this body has both natural and anthropogenically modified weathering profiles only 500 m apart. The orebody is located in a heavily urbanized area in suburban Oakland, and directly affects water quality in at least one stream by producing acidic conditions and relatively high concentrations of dissolved elements (e.g., {approx}500 mg/L Cu, {approx}3700 mg/L Zn). Micrometric-scale mineralogical investigations were performed on the authigenic metal-bearing phases (less thanmore » 10 {mu}m in size) using electron-probe micro-analysis (EPMA), micro-Raman, micro X-ray absorption spectroscopy (mXAS), scanning X-ray diffraction (mSXRD) and scanning X-ray fluorescence (mSXRF) mapping techniques. Those measurements were coupled with classical mineralogical laboratory techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Authigenic metal-bearing phases identified are mainly sulfates (jarosite, epsomite, schwertmannite), Fe (oxy-)hydroxides (goethite, hematite and poorly crystalline Fe products) and poorly crystalline Mn (hydr-)oxides. Sulfates and Fe (oxy-)hydroxides are the two main secondary products at both sites, whereas Mn (hydr-) oxides were only observed in the samples from the non-mining site. In these samples, the various trace elements show different affinities for Fe or Mn compounds. Lead is preferentially associated with Mn (hydr-)oxides and As with Fe (oxy-)hydroxides or sulfates. Copper association with Mn and Fe phases is questionable, and the results obtained rather indicate that Cu is present as individual Cu-rich grains (Cu hydroxides). Some ochreous precipitates were found at both sites and correspond to a mixture of schwertmannite, goethite and jarosite containing some potentially toxic trace elements such as Cu, Pb and Zn. According to the trace element distribution and relative abundance of the unweathered sulfides, this orebody still represents a significant reservoir of potential contaminants for the watershed, especially in the non-mining site, as a much greater proportion of sulfides is left to react and because of the lower porosity in this site.« less

The weathering of a sulfide orebody: Speciation and fate of some potential contaminants

USGS Publications Warehouse

Courtin-Nomade, A.; Grosbois, C.; Marcus, M.A.; Fakra, S.C.; Beny, J.-M.; Foster, A.L.

2009-01-01

Various potentially toxic trace elements such as As, Cu, Pb and Zn have been remobilized by the weathering of a sulfide orebody that was only partially mined at Leona Heights, California. As a result, this body has both natural and anthropogeni- cally modified weathering profiles only 500 m apart. The orebody is located in a heavily urbanized area in suburban Oakland, and directly affects water quality in at least one stream by producing acidic conditions and relatively high concentrations of dissolved elements (e.g., ??500 ??g/L Cu, ??3700 ??g/L Zn). Micrometric-scale mineralogical investigations were performed on the authigenic metal-bearing phases (less than 10 ??m in size) using electron-probe micro-analysis (EPMA), micro-Raman, micro X-ray absorption spectroscopy (??XAS), scanning X-ray diffraction ((??SXRD) and scanning X-ray fluorescence (??-SXRF) mapping techniques. Those measurements were coupled with classical mineralogical laboratory techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Authigenic metal-bearing phases identified are mainly sulfates (jarosite, epsomite, schwertmannite), Fe (oxy-)hydroxides (goethite, hematite and poorly crystalline Fe products) and poorly crystalline Mn (hydr-)oxides. Sulfates and Fe (oxy-)hydroxides are the two main secondary products at both sites, whereas Mn (hydr-) oxides were only observed in the samples from the non-mining site. In these samples, the various trace elements show different affinities for Fe or Mn compounds. Lead is preferentially associated with Mn (hydr-)oxides and As with Fe (oxy-)hydroxides or sulfates. Copper association with Mn and Fe phases is questionable, and the results obtained rather indicate that Cu is present as individual Cu-rich grains (Cu hydroxides). Some ochreous precipitates were found at both sites and correspond to a mixture of schwertmannite, goethite and jarosite containing some potentially toxic trace elements such as Cu, Pb and Zn. According to the trace element distribution and relative abundance of the unweathered sulfides, this orebody still represents a significant reservoir of potential contaminants for the watershed, especially at the non-mining site, as a much greater proportion of sulfides is left to react and because of the lower porosity at this site.

Formation of hydrotalcite in aqueous solutions and intercalation of ATP by anion exchange.

PubMed

Tamura, Hiroki; Chiba, Jun; Ito, Masahiro; Takeda, Takashi; Kikkawa, Shinichi; Mawatari, Yasuteru; Tabata, Masayoshi

2006-08-15

The formation reaction and the intercalation of adenosine triphosphate (ATP) were studied for hydrotalcite (HT), a layered double hydroxide (LDH) of magnesium and aluminum. Hydrotalcite with nitrate ions in the interlayer (HT-NO(3)) was formed (A) by dropwise addition of a solution of magnesium and aluminum nitrates (pH ca. 3) to a sodium hydroxide solution (pH ca. 14) until the pH decreased from 14 to 10 and (B) by dropwise addition of the NaOH solution to the solution of magnesium and aluminum nitrates with pH increasing from 3 to 10. The precipitate obtained with method B was contaminated with aluminum hydroxide and the crystallinity of the product was low, possibly because aluminum hydroxide precipitates at pH 4 or 5 and remains even after HT-NO(3) forms at pH above 8. With method A, however, the precipitate was pure HT-NO(3) with increased crystallinity, since the solubility of aluminum hydroxide at pH above and around 10 is high as dissolved aluminate anions are stable in this high pH region, and there was no aluminum hydroxide contamination. The formed HT-NO(3) had a composition of [Mg(0.71)Al(0.29)(OH)(2)](NO(3))(0.29).0.58H(2)O. To intercalate ATP anions into the HT-NO(3), HT-NO(3) was dispersed in an ATP solution at pH 7. It was found that the interlayer nitrate ions were completely exchanged with ATP anions by ion exchange, and the interlayer distance expanded almost twice with a free space distance of 1.2 nm. The composition of HT-ATP was established as [Mg(0.68)Al(0.32)(OH)(2)](ATP)(0.080)0.88H(2)O. The increased distance could be explained with a calculated molecular configuration of the ATP as follows: An ATP molecule is bound to an interlayer surface with the triphosphate group, the adenosine group bends owing to its bond angles and projects into the interlayer to a height of 1 nm, and the adenosine groups aligned in the interlayer support the interlayer distance.

A comparison between effect of photodynamic therapy by LED and calcium hydroxide therapy for root canal disinfection against Enterococcus faecalis: A randomized controlled trial.

PubMed

Asnaashari, Mohammad; Ashraf, Hengameh; Rahmati, Afsaneh; Amini, Neda

2017-03-01

Insufficient root canal disinfection is one of the main reasons for persistent periapical pathology. Photodynamic therapy (PDT) has been proven effective in disinfecting infected root canals. The aim of this study was to evaluate the antimicrobial effect of photo activated disinfection (PAD) when using toluidine blue as photosensitizer and a LED lamp after the conventional treatment, and comparing it with calcium hydroxide therapy in vivo. This clinical trial includes 20 patients with molars requiring endodontic retreatment. After the conventional treatment, first microbiological samples were obtained using sterile rotary ProTaper F2 file and 3 paper points and transferred to a microbiology laboratory. Group 1 (n=10) specimens underwent PAD with photosensitizer (PS) solution (0.1mg/mL TB) and irradiation with Fotosan light emitting diode (LED) lamp (635nm, 200mW/cm2) for 60s. Creamy Ca(OH)2 paste was used in group 2 (n=10) for two weeks. A second sample was then obtained. The samples were cultured and then bacterial colonies were counted. Data included number of colony forming units (CFUs) before and after treatments, analyzed by t-test and analysis of covariance (ANCOVA) using SPSS vs.18. A significant difference between results of before and after treatment of both groups (calcium hydroxide therapy p=0.02<0.05, PAD p<0.0001) indicated the efficacy of both treatments. The mean numbers for log 10CFUs/mL before calcium hydroxide therapy and PAD with LED irradiation was 10.1968 and 11.3773. After treatment, the mean numbers were 9.4202 and 8.3772, respectively. The difference in results after treatment between groups was significant (p=0.01<0.05) and indicate that PAD was more effective. PAD and calcium hydroxide therapy, as auxiliary methods adjunct to conventional root canal therapy, are both effective in root canal disinfection. In comparison with calcium hydroxide therapy, PAD leads to a greater reduction in enterococcus faecalis number in the infected root canals. Copyright © 2016 Elsevier B.V. All rights reserved.

LEACHING OF TITANIUM FROM MONOSODIUM TITANATE AND MODIFIED MST

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor-Pashow, K.; Fondeur, F.; Fink, S.

2012-08-01

Analysis of a fouled coalescer and pre-filters from Actinide Removal Process/Modular Caustic Side Solvent Extraction Unit (ARP/MCU) operations showed evidence of Ti containing solids. Based on these results a series of tests were planned to examine the extent of Ti leaching from monosodium titanate (MST) and modified monosodium titanate (mMST) in various solutions. The solutions tested included a series of salt solutions with varying free hydroxide concentrations, two sodium hydroxide concentrations, 9 wt % and 15 wt %, nitric and oxalic acid solutions. Overall, the amount of Ti leached from the MST and mMST was much greater in the acidmore » solutions compared to the sodium hydroxide or salt solutions, which is consistent with the expected trend. The leaching data also showed that increasing hydroxide concentration, whether pure NaOH solution used for filter cleaning in ARP or the waste salt solution, increased the amount of Ti leached from both the MST and mMST. For the respective nominal contact times with the MST solids - for filter cleaning or the normal filter operation, the dissolved Ti concentrations are comparable suggesting either cause may contribute to the increased Ti fouling on the MCU coalescers. Tests showed that Ti containing solids could be precipitated from solution after the addition of scrub acid and a decrease in temperature similar to expected in MCU operations. FTIR analysis of these solids showed some similarity to the solids observed on the fouled coalescer and pre-filters. Although only a cursory study, this information suggests that the practice of increasing free hydroxide in feed solutions to MCU as a mitigation to aluminosilicate formation may be offset by the impact of formation of Ti solids in the overall process. Additional consideration of this finding from MCU and SWPF operation is warranted.« less

Extraction of starch from hulled and hull-less barley with papain and aqueous sodium hydroxide.

PubMed

Sharma, Priyanka; Tejinder, S

2014-12-01

Starch was isolated from hulled (VJM 201) and hull-less (BL 134) barley with papain and aqueous sodium hydroxide treatments. For enzyme-assisted extraction, barley was steeped in water containing 0.2 % SO2 + 0.55 % lactic acid at 50° ± 2 °C for 4-5 h. The slurry was mixed with 0.4-2.0 g papain/kg barley and incubated at 50° ± 2 °C for 1-5 h. Aqueous sodium hydroxide (0.01-0.05 M) was added to the finely ground barley meal. The alkaline slurry was incubated at ambient temperature (25° ± 2 °C) for 15-60 min. The starch and grain fractions were isolated by screening and centrifugation. Increases in the time of treatment significantly affected the fiber, centrifugation and non-starch residue losses. Concentration of papain and sodium hydroxide had negligible effect on extraction losses. The enzyme-assisted extraction efficiency of starch was higher (80.7-84.6 %) than the alkaline method (70.9-83.7 %). The hulled barley showed higher extraction efficiency than the hull-less barley. The slurry treated with 0.4 g papain/kg barley for 5 h and 0.03 M sodium hydroxide for 60 min produced maximal yield of starch. Barley starch showed desirably high pasting temperature, water binding capacity and hold viscosity; and low final and setback viscosity compared with the commercial corn starch. The alkaline extracted hull-less barley starch showed exceptionally high peak and hold viscosities.

[Determination of total mass and morphology analysis of heavy metal in soil with potassium biphthalate-sodium hydroxide by ICP-AES].

PubMed

Qu, Jiao; Yuan, Xing; Cong, Qiao; Wang, Shuang

2008-11-01

Blank soil was used as quality controlling samples, soil sample dealt by potassium biphthalate-sodium hydroxide buffer solution was used as check sample, mixed acid HNO3-HF-HClO4 was chosen to nitrify soil samples, and plasma emission spectrometer (ICP-AES) was used as detecting method. The authors determined the total metal mass of Mo, Pb, As, Hg, Cr, Cd, Zn, Cu and Ni in the extracted and dealt soil samples, and determined the mass of Mo, Pb, As, Hg, Cr, Cd, Zn, Cu and Ni in the three chemical morphologies, including acid extractable morphology, oxide associated morphology, and organics associated modality. The experimental results indicated that the different pH of potassium biphthalate-sodium hydroxide buffer solution had obvious influence on the total mass of heavy metal and morphology transformation. Except for metal element Pb and Zn, the addition of different pH potassium dihydrogen phosphate-sodium hydroxide buffer solution could accelerate the soil samples nitrification and the total mass determination of heavy metal in the soil samples. The potassium biphthalate-sodium hydroxide buffer solution could facilitate the acid extractable morphology of Cr, Cu, Hg and Pb, oxidation associated morphology of As, Hg, Pb and Zn and the organic associated morphology transforming of As and Hg. At pH 5.8, the maximum acid extractable morphology contents of Cu and Hg were 2.180 and 0.632 mg x kg(-1), respectively; at pH 6.2, the maximal oxidation associated morphology content of Pb could achieve 27.792 mg x kg(-1); at pH 6.0, the maximum organic associated morphology content of heavy metal Hg was 4.715 mg x kg(-1).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petersen, Line Boisen; Lipton, Andrew S.; Zorin, Vadim

Ordering of gallium(III) in a series of magnesium gallium (MgGa) layered double hydroxides (LDHs), [Mg{sub 1−x}Ga{sub x}(OH){sub 2}(NO{sub 3}){sub x}·yH{sub 2}O] was investigated using solid-state {sup 1}H and {sup 71}Ga NMR spectroscopy as well as powder X-ray diffraction. Three different proton environments from Mg{sub 3}-OH, Mg{sub 2}Ga-OH and intergallery water molecules were assigned and quantified using ({sup 1}H,{sup 71}Ga) HETCOR and {sup 1}H MAS NMR. A single {sup 71}Ga site originating from the unique Ga site in the MgGa LDH's was observed in {sup 71}Ga MAS and 3QMAS NMR spectra. Both {sup 1}H MAS NMR spectra recorded at 21.1 Tmore » (900 MHz) and elemental analysis show that the synthesized MgGa LDH's had a lower Mg:Ga ratio than that of the starting reactant solution. The origin of this is the formation of soluble [Ga(OH){sub 4}]{sup −} complexes formed during synthesis, and not due to formation of insoluble gallium (oxy)hydroxides. No sign of Ga-O-Ga connectivities or defects were detected for the MgGa LDH's. - Graphical abstract: Two types of hydroxides groups are observed in magnesium gallium layered double hydroxides revealing an ordering of Ga in the cation layer. - Highlights: • Ga is ordered in our magnesium gallium layered double hydroxides. • Ga depletion due to formation of soluble Ga complexes during synthesis. • No sign of Ga rich regions in magnesium gallium LDHs. • Solid state {sup 1}H and {sup 71}Ga give detailed insight into the structure.« less

Layered zinc hydroxide nanocones: synthesis, facile morphological and structural modification, and properties

NASA Astrophysics Data System (ADS)

Ma, Wei; Ma, Renzhi; Liang, Jianbo; Wang, Chengxiang; Liu, Xiaohe; Zhou, Kechao; Sasaki, Takayoshi

2014-10-01

Layered zinc hydroxide nanocones intercalated with DS- have been synthesized for the first time via a convenient synthetic approach, using homogeneous precipitation in the presence of urea and sodium dodecyl sulfate (SDS). SDS plays a significant role in controlling the morphologies of as-synthesized samples. Conical samples intercalated with various anions were transformed through an anion-exchange route in ethanol solution, and the original conical structure was perfectly maintained. Additionally, these DS--inserted nanocones can be transformed into square-like nanoplates in aqueous solution at room temperature, fulfilling the need for different morphology-dependent properties. Corresponding ZnO nanocones and nanoplates have been further obtained through the thermal calcination of NO3--intercalating zinc hydroxide nanocones/nanoplates. These ZnO nanostructures with different morphologies exhibit promising photocatalytic properties.Layered zinc hydroxide nanocones intercalated with DS- have been synthesized for the first time via a convenient synthetic approach, using homogeneous precipitation in the presence of urea and sodium dodecyl sulfate (SDS). SDS plays a significant role in controlling the morphologies of as-synthesized samples. Conical samples intercalated with various anions were transformed through an anion-exchange route in ethanol solution, and the original conical structure was perfectly maintained. Additionally, these DS--inserted nanocones can be transformed into square-like nanoplates in aqueous solution at room temperature, fulfilling the need for different morphology-dependent properties. Corresponding ZnO nanocones and nanoplates have been further obtained through the thermal calcination of NO3--intercalating zinc hydroxide nanocones/nanoplates. These ZnO nanostructures with different morphologies exhibit promising photocatalytic properties. Electronic supplementary information (ESI) available: Typical SEM images, TGA curves and XRD patterns of as-prepared samples. See DOI: 10.1039/c4nr04166f

Electronic and Morphological Dual Modulation of Cobalt Carbonate Hydroxides by Mn Doping toward Highly Efficient and Stable Bifunctional Electrocatalysts for Overall Water Splitting.

PubMed

Tang, Tang; Jiang, Wen-Jie; Niu, Shuai; Liu, Ning; Luo, Hao; Chen, Yu-Yun; Jin, Shi-Feng; Gao, Feng; Wan, Li-Jun; Hu, Jin-Song

2017-06-21

Developing bifunctional efficient and durable non-noble electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is highly desirable and challenging for overall water splitting. Herein, Co-Mn carbonate hydroxide (CoMnCH) nanosheet arrays with controllable morphology and composition were developed on nickel foam (NF) as such a bifunctional electrocatalyst. It is discovered that Mn doping in CoCH can simultaneously modulate the nanosheet morphology to significantly increase the electrochemical active surface area for exposing more accessible active sites and tune the electronic structure of Co center to effectively boost its intrinsic activity. As a result, the optimized Co 1 Mn 1 CH/NF electrode exhibits unprecedented OER activity with an ultralow overpotential of 294 mV at 30 mA cm -2 , compared with all reported metal carbonate hydroxides. Benefited from 3D open nanosheet array topographic structure with tight contact between nanosheets and NF, it is able to deliver a high and stable current density of 1000 mA cm -2 at only an overpotential of 462 mV with no interference from high-flux oxygen evolution. Despite no reports about effective HER on metal carbonate hydroxides yet, the small overpotential of 180 mV at 10 mA cm -2 for HER can be also achieved on Co 1 Mn 1 CH/NF by the dual modulation of Mn doping. This offers a two-electrode electrolyzer using bifunctional Co 1 Mn 1 CH/NF as both anode and cathode to perform stable overall water splitting with a cell voltage of only 1.68 V at 10 mA cm -2 . These findings may open up opportunities to explore other multimetal carbonate hydroxides as practical bifunctional electrocatalysts for scale-up water electrolysis.

Iron Hydroxide Minerals Drive Organic and Phosphorus Chemistry in Subsurface Redox / pH Gradients

NASA Astrophysics Data System (ADS)

Flores, E.; Barge, L. M.; VanderVelde, D.; Baum, M.

2017-12-01

Iron minerals, particularly iron oxides and oxyhydroxides, are prevalent on Mars and may exist in mixed valence or even reduced states beneath the oxidized surface. Iron (II,III) hydroxides, including green rust, are reactive and potentially catalytic minerals that can absorb and concentrate charged species, while also driving chemical reactions. These minerals are highly redox-sensitive and the presence of organics and/or phosphorus species could affect their mineralogy and/or stability. Conversely, the minerals might be able to drive chemical processes such as amino acid formation, phosphorus oxyanion reactions, or could simply selectively preserve organic species via surface adsorption. In an open aqueous sediment column, soluble products of mineral-driven reactions could also diffuse to sites of different chemical conditions to react even further. We synthesized Fe-hydroxide minerals under various conditions relevant to early Earth and ancient Mars (>3.0 Gyr), anoxically and in the presence of salts likely to have been present in surface or ground waters. Using these minerals we conducted experiments to test whether iron hydroxides could promote amino acid formation, and how the reaction is affected by subsurface gradients of redox, pH, and temperature. We also tested the adsorption of organic and phosphorus species onto Fe-hydroxide minerals at different conditions within the gradients. The suite of organic or phosphorus signatures that may be found in a particular mineral system is a combination of what is synthesized there, what is preferentially concentrated / retained there, and what is preserved against degradation. Further work is needed to determine how these processes could have proceeded on Mars and what mineral-organic signatures, abiotic or otherwise, would be produced from such processes.

Theoretical investigation on the mechanism and dynamics of oxo exchange of neptunyl(VI) hydroxide in aqueous solution.

PubMed

Yang, Xia; Chai, Zhifang; Wang, Dongqi

2015-03-21

Four types of reaction mechanisms for the oxo ligand exchange of monomeric and dimeric neptunyl(VI) hydroxide in aqueous solution were explored computationally using density functional theory (DFT) and ab initio classical molecular dynamics. The obtained results were compared with previous studies on the oxo exchange of uranyl hydroxide, as well as with experiments. It is found that the stable T-shaped [NpO3(OH)3](3-) intermediate is a key species for oxo exchange in the proton transfer in mononuclear Path I and binuclear Path IV, similar to the case of uranyl(VI) hydroxide. Path I is thought to be the preferred oxo exchange mechanism for neptunyl(VI) hydroxide in our calculations, due to the lower activation energy (22.7 and 13.1 kcal mol(-1) for ΔG(‡) and ΔH(‡), respectively) of the overall reaction. Path II via a cis-neptunyl structure assisted by a water molecule might be a competitive channel against Path I with a mononuclear mechanism, owing to a rapid dynamical process occurring in Path II. In Path IV with the binuclear mechanism, oxo exchange is accomplished via the interaction between [NpO2(OH)4](2-) and T-shaped [NpO3(OH)3](3-) with a low activation energy for the rate-determining step, however, the overall energy required to fulfill the reaction is slightly higher than that in mononuclear Path I, suggesting a possible binuclear process in the higher energy region. The chemical bonding evolution along the reaction pathways was discussed by using topological methodologies of the electron localization function (ELF).

Minimization of steam requirements and enhancement of water-gas shift reaction with warm gas temperature CO2 removal

DOEpatents

Siriwardane, Ranjani V; Fisher, II, James C

2013-12-31

The disclosure utilizes a hydroxide sorbent for humidification and CO.sub.2 removal from a gaseous stream comprised of CO and CO.sub.2 prior to entry into a water-gas-shift reactor, in order to decrease CO.sub.2 concentration and increase H.sub.2O concentration and shift the water-gas shift reaction toward the forward reaction products CO.sub.2 and H.sub.2. The hydroxide sorbent may be utilized for absorbtion of CO.sub.2 exiting the water-gas shift reactor, producing an enriched H.sub.2 stream. The disclosure further provides for regeneration of the hydroxide sorbent at temperature approximating water-gas shift conditions, and for utilizing H.sub.2O product liberated as a result of the CO.sub.2 absorption.

Prebiotic Oxidative Polymerization of 2,3 Dimercaptopropanol on the Surface of Iron(III) Hydroxide Oxide

NASA Technical Reports Server (NTRS)

Weber, Arthur L.

1994-01-01

The oxidation of 2,3-Dimercapto-1-propanol by ferric ions on the surface of iron (III) hydroxide oxide yielded polydisulfide polymers. This polymerization occured readily at low dithiol concentration under mild aqueous conditions. Polydisulfide polymers up to the 15-mer were synthesized from 1 mM dithiol in 5 ml water reacted with iron (III) hydroxide oxide (20 mg, 160 micro mole Fe) for 3 days under anaerobic conditions at 40 C and pH 4. About 91% of the dithiol was converted to short soluble oligomers and 9% to insoluble larger oligomers that were isolated with the mineral phase. Reactions at higher dithiol concentrations with the same ratio of dithiol to mineral gave a higher yield of the larger insoluble oligomers. The relationship of these results to prebiotic polymer synthesis will be discussed.

Evaluation of the Magnesium Hydroxide Treatment Process for Stabilizing PFP Plutonium/Nitric Acid Solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gerber, Mark A.; Schmidt, Andrew J.; Delegard, Calvin H.

2000-09-28

This document summarizes an evaluation of the magnesium hydroxide [Mg(OH)2] process to be used at the Hanford Plutonium Finishing Plant (PFP) for stabilizing plutonium/nitric acid solutions to meet the goal of stabilizing the plutonium in an oxide form suitable for storage under DOE-STD-3013-99. During the treatment process, nitric acid solutions bearing plutonium nitrate are neutralized with Mg(OH)2 in an air sparge reactor. The resulting slurry, containing plutonium hydroxide, is filtered and calcined. The process evaluation included a literature review and extensive laboratory- and bench-scale testing. The testing was conducted using cerium as a surrogate for plutonium to identify and quantifymore » the effects of key processing variables on processing time (primarily neutralization and filtration time) and calcined product properties.« less

Alternative Sodium Recovery Technology—High Hydroxide Leaching: FY10 Status Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahoney, Lenna A.; Neiner, Doinita; Peterson, Reid A.

2011-02-04

Boehmite leaching tests were carried out at NaOH concentrations of 10 M and 12 M, temperatures of 85°C and 60°C, and a range of initial aluminate concentrations. These data, and data obtained during earlier 100°C tests using 1 M and 5 M NaOH, were used to establish the dependence of the boehmite dissolution rate on hydroxide concentration, temperature, and initial aluminate concentration. A semi-empirical kinetic model for boehmite leaching was fitted to the data and used to calculate the NaOH additions required for leaching at different hydroxide concentrations. The optimal NaOH concentration for boehmite leaching at 85°C was estimated, basedmore » on minimizing the amount of Na that had to be added in NaOH to produce a given boehmite conversion.« less

Synthesis and characterization of α-cobalt hydroxide nanobelts

NASA Astrophysics Data System (ADS)

Tian, L.; Zhu, J. L.; Chen, L.; An, B.; Liu, Q. Q.; Huang, K. L.

2011-08-01

α-Cobalt hydroxide was synthesized by a facile hydrothermal process from Co(Ac)2 and NH3·H2O in the presence of 1,3-propanediol. The large-scale-prepared cobalt hydroxide has a uniform nanobelt morphology with a considerably high aspect-ratio more than 20 which may be advantageous for exploration of their physicochemical properties. This synthetic method is convenient, economical, and controllable. The samples were characterized by powder X-ray diffraction, energy dispersive spectrum, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, CHN element analysis, thermogravimetric and differential-thermogravimetric analysis, which revealed the compound is lamellar structural cobalt organic-inorganic hybrid with the chemical formula of Co(OH)1.49(NH3)0.01(CO3 2-)0.22(Ac-)0.07(H2O)0.11 and single-crystalline.

Anion-exchange membranes derived from quaternized polysulfone and exfoliated layered double hydroxide for fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Wan; Liang, Na; Peng, Pai

2017-02-15

Layered double hydroxides (LDH) are prepared by controlling urea assisted homogeneous precipitation conditions. Morphology and crystallinity of LDHs are confirmed by X-ray diffraction and scanning electron microscope. After LDHs are incorporated into quaternized polysulfone membranes, transmission electron microscope is used to observe the exfoliated morphology of LDH sheets in the membranes. The properties of the nanocomposite membranes, including water uptake, swelling ratio, mechanical property and ionic conductivity are investigated. The nanocomposite membrane containing 5% LDH sheets shows more balanced performances, exhibiting an ionic conductivity of 2.36×10{sup −2} S cm{sup −1} at 60 °C. - Graphical abstract: Anion-exchange membrane based onmore » quaternized polysulfone and exfoliated layered double hydroxide is optically transparent and has good ionic properties.« less

Evaluation of barium hydroxide treatment efficacy on a dolomitic marble.

PubMed

Toniolo, L; Colombo, C; Realini, M; Peraio, A; Positano, M

2001-01-01

The Arch of Peace, by Luigi Cagnola, is one of the most famous neoclassical monuments in Milan. It has been subjected to conservative intervention in 1998. In the present paper the efficacy of the consolidation by means of barium hydroxide has been evaluated. The stone material showed severe degradation phenomena as: erosion, pulverisation, exfoliation. The analytical data acquired through X-ray diffraction (XRD), infrared spectrophotometry (FTIR) and scanning electron microscopy (SEM-EDX), allowed to compare the conditions of stone before and after the treatment with barium hydroxide. The presence of barium has been put in evidence mainly on the surface as barium sulphate, whereas barium is only sporadically present within the thickness of the decayed material. The treatment was judged not satisfying and its inefficacy is, most probably, due to a not suitable cleaning procedure carried out before the consolidation.

Niobium powder synthesized by calciothermic reduction of niobium hydroxide for use in capacitors

NASA Astrophysics Data System (ADS)

Baba, Masahiko; Kikuchi, Tatsuya; Suzuki, Ryosuke O.

2015-03-01

Metallic niobium powder was produced for applications in electric capacitors via calciothermic reduction of niobium hydroxide in molten CaCl2. Sub-micrometer spherical metallic particles with coral-like morphologies reflected the particle size of the starting oxide powder. A fine powder was obtained from the mixtures of niobium hydroxide and CaO or Ca(OH)2, respectively. Sintered pellets of the metallic powder showed a higher capacitance (CV) than those of the simply reduced powder without pre-treatment, because the shrinkage during sintering was smaller. The CV was as large as that of commercially sintered pellets for tantalum capacitors. Therefore, this niobium powder would act as a higher-voltage capacitor by applying chemical anodic treatment at higher voltages, and lower oxygen content in the reduced power could realize a lower leak current.

Hydroxide-catalyzed bonding

NASA Technical Reports Server (NTRS)

Gwo, Dz-Hung (Inventor)

2003-01-01

A method of bonding substrates by hydroxide-catalyzed hydration/dehydration involves applying a bonding material to at least one surface to be bonded, and placing the at least one surface sufficiently close to another surface such that a bonding interface is formed between them. A bonding material of the invention comprises a source of hydroxide ions, and may optionally include a silicate component, a particulate filling material, and a property-modifying component. Bonding methods of the invention reliably and reproducibly provide bonds which are strong and precise, and which may be tailored according to a wide range of possible applications. Possible applications for bonding materials of the invention include: forming composite materials, coating substrates, forming laminate structures, assembly of precision optical components, and preparing objects of defined geometry and composition. Bonding materials and methods of preparing the same are also disclosed.

Microbial susceptibility to calcium hydroxide pastes and their vehicles.

PubMed

Gomes, Brenda Paula Figueiredo de Almeida; Ferraz, Caio Cezar Randi; Garrido, Fabio Devora; Rosalen, Pedro Luiz; Zaia, Alexandre Augusto; Teixeira, Fabricio Batista; de Souza-Filho, Francisco José

2002-11-01

The aim of this study was to investigate the susceptibility of some microorganisms commonly isolated from root canals to calcium hydroxide in combination with several vehicles by the agar diffusion method. Stainless-steel cylinders were placed on each inoculated agar medium. The test medications and their controls were placed inside the cylinders. The zones of growth inhibition were measured and recorded after the incubation period for each plate, and the results were analyzed statistically. Enterococcus faecalis was most resistant, whereas the anaerobic Porphyromonas endodontalis was more susceptible to all medications, followed by P. gingivalis and Prevotella intermedial intermedia. Ca(OH)2 + CMCP + glycerin showed significantly larger mean zones of inhibition when compared with the other medications. We conclude that anaerobic Gram-negative bacteria are more susceptible to calcium hydroxide pastes than facultative Gram-positive microorganisms.

Interior view of "mail box" for purging carbon dioxide from Lunar Module

NASA Image and Video Library

1970-04-14

AS13-62-8929 (11-17 April 1970) --- Interior view of the Apollo 13 Lunar Module (LM) showing the "mail box," a jury-rigged arrangement which the Apollo 13 astronauts built to use the Command Module (CM) lithium hydroxide canisters to purge carbon dioxide from the LM. Lithium hydroxide is used to scrub CO2 from the spacecraft's atmosphere. Since there was a limited amount of lithium hydroxide in the LM, this arrangement was rigged up to utilize the canisters from the CM. The "mail box" was designed and tested on the ground at the Manned Spacecraft Center (MSC) before it was suggested to the problem-plagued Apollo 13 crew men. Because of the explosion of one of the oxygen tanks in the Service Module (SM), the three crew men had to use the LM as a "lifeboat".

Facile synthesis of nickel-cobalt double hydroxide nanosheets with high rate capability for application in supercapacitor

NASA Astrophysics Data System (ADS)

Wang, Minmin; Xue, Junying; Zhang, Fangming; Ma, Wenle; Cui, Hongtao

2015-02-01

In this work, nickel-cobalt double hydroxide nanosheets with high rate capability are prepared by a facile epoxide precipitation route. The synthetic procedure includes an oxidization step using ammonium persulfate as oxidant and a precipitation step using propylene oxide as precipitation agent. As shown in the results of electrochemical characterization, high specific capacitance of 2548 F g-1 for this material can be obtained at current density of 0.9 A g-1 in aqueous solution of 3 mol L-1 KOH. It is surprising to notice that the capacitance of material still remains 1587 F g-1 at high current density of 35.7 A g-1. These results demonstrate that the as-prepared nickel-cobalt double hydroxide nanosheets are promising electrode material for supercapacitor application as a primary power source.

Chemical degradation mechanisms of membranes for alkaline membrane fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choe, Yoong-Kee; Henson, Neil J.; Kim, Yu Seung

2015-12-31

Chemical degradation mechanisms of membranes for alkaline membrane fuel cells have been investigated using density functional theory (DFT). We have elucidated that the aryl-ether moiety of membranes is one of the weakest site against attack of hydroxide ions. The results of DFT calculations for hydroxide initiated aryl-ether cleavage indicated that the aryl-ether cleavage occurred prior to degradation of cationic functional group. Such a weak nature of the aryl-ether group arises from the electron deficiency of the aryl group as well as the low bond dissociation energy. The DFT results suggests that removal of the aryl-ether group in the membrane shouldmore » enhance the stability of membranes under alkaline conditions. In fact, an ether fee poly(phenylene) membrane exhibits excellent stability against the attack from hydroxide ions.« less

Long-Term Experimental Determination of Solubilities of Micro-Crystalline Nd(III) Hydroxide in High Ionic Strength Solutions: Applications to Nuclear Waste Management [A Pitzer Model for Am(III)/Nd(III) hydroxide solubility in NaCl-H 2O at 298.15 K to high ionic strengths: Experimental validation and model applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiong, Yongliang; Kirkes, Leslie Dawn; Marrs, Cassandra

In this paper, the experimental results from long-term solubility experiments on micro crystalline neodymium hydroxide, Nd(OH) 3(micro cr), in high ionic strength solutions at 298.15 K under well-constrained conditions are presented. The starting material was synthesized according to a well-established method in the literature. In contrast with the previous studies in which hydrogen ion concentrations in experiments were adjusted with addition of either an acid or a base, the hydrogen ion concentrations in our experiments are controlled by the dissolution of Nd(OH) 3(micro cr), avoiding the possibility of phase change.

A mini-type hydrogen generator from aluminum for proton exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Wang, Er-Dong; Shi, Peng-Fei; Du, Chun-Yu; Wang, Xiao-Rui

A safe and simple hydrogen generator, which produced hydrogen by chemical reaction of aluminum and sodium hydroxide solution, was proposed for proton exchange membrane fuel cells. The effects of concentration, dropping rate and initial temperature of sodium hydroxide solution on hydrogen generation rate were investigated. The results showed that about 38 ml min -1 of hydrogen generation rate was obtained with 25 wt.% concentration and 0.01 ml s -1 dropping rate of sodium hydroxide solution. The cell fueled by hydrogen from the generator exhibited performance improvement at low current densities, which was mainly due to the humidified hydrogen reduced the protonic resistivity of the proton exchange membrane. The hydrogen generator could stably operate a single cell under 500 mA for nearly 5 h with about 77% hydrogen utilization ratio.

Hierarchical cobalt-based hydroxide microspheres for water oxidation.

PubMed

Zhang, Ye; Cui, Bai; Derr, Olivia; Yao, Zhibo; Qin, Zhaotong; Deng, Xiangyun; Li, Jianbao; Lin, Hong

2014-03-21

3D hierarchical cobalt hydroxide carbonate hydrate (Co(CO3)0.5(OH)·0.11H2O) has been synthesized featuring a hollow urchin-like structure by a one-step hydrothermal method at modest temperature on FTO glass substrates. The functionalities of precursor surfactants were isolated and analyzed. A plausible formation mechanism of the spherical urchin-like microclusters has been furnished through time-dependent investigations. Introduction of other transitional metal doping (Cu, Ni) would give rise to a substantial morphological change associated with a surface area drop. The directly grown cobalt-based hydroxide composite electrodes were found to be capable of catalyzing oxygen evolution reaction (OER) under both neutral pH and alkaline conditions. The favorable 3D dendritic morphology and porous structure provide large surface areas and possible defect sites that are likely responsible for their robust electrochemical activity.

Long-Term Experimental Determination of Solubilities of Micro-Crystalline Nd(III) Hydroxide in High Ionic Strength Solutions: Applications to Nuclear Waste Management [A Pitzer Model for Am(III)/Nd(III) hydroxide solubility in NaCl-H 2O at 298.15 K to high ionic strengths: Experimental validation and model applications

DOE PAGES

Xiong, Yongliang; Kirkes, Leslie Dawn; Marrs, Cassandra

2017-12-01

In this paper, the experimental results from long-term solubility experiments on micro crystalline neodymium hydroxide, Nd(OH) 3(micro cr), in high ionic strength solutions at 298.15 K under well-constrained conditions are presented. The starting material was synthesized according to a well-established method in the literature. In contrast with the previous studies in which hydrogen ion concentrations in experiments were adjusted with addition of either an acid or a base, the hydrogen ion concentrations in our experiments are controlled by the dissolution of Nd(OH) 3(micro cr), avoiding the possibility of phase change.

Intercalation of anionic organic ultraviolet ray absorbers into layered zinc hydroxide nitrate.

PubMed

Cursino, Ana Cristina Trindade; Gardolinski, José Eduardo Ferreira da Costa; Wypych, Fernando

2010-07-01

Layered zinc hydroxide nitrate (ZHN) was synthesized and nitrate ions were topotactically exchanged with three different anionic species of commercial organic ultraviolet (UV) ray absorbers: 2-mercaptobenzoic acid, 2-aminobenzoic acid, and 4-aminobenzoic acid. The exchange reactions were confirmed by X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), ultraviolet visible (UV-Vis) spectroscopy, and thermal analysis (thermogravimetry, TGA, and differential thermal analysis, DTA). In all the anionic exchanged products, evidence of grafting of the organic species onto the inorganic matrix was obtained. In general, after intercalation/grafting, the UV absorption ability was improved in relation to the use of the parent organic material, showing that layered hydroxide salts (LHS) can be good alternative matrixes for the immobilization of organic species with UV-blocking properties in cosmetic products. Copyright 2010 Elsevier Inc. All rights reserved.

Agent neutralization study IV. VX-caustic peroxide reactions. Final report, August 1993-February 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hovanec, J.W.; Albizo, J.M.; Henderson, V.D.

1994-08-01

The use of concentrated mixtures of hydrogen peroxide and sodium hydroxide for the chemical neutralization (detoxification) of VX has been examined. The reaction of VX in 4 N sodium hydroxide/11% hydrogen peroxide is rapid and exothermic. Care must be taken to avoid temperature increases which can induce peroxide decomposition. This can be done by controlling the addition of VX to the reaction. (Author).

Removal of Zn or Cd and cyanide from cyanide electroplating wastes

DOEpatents

Moore, Fletcher L.

1977-05-31

A method is described for the efficient stripping of stable complexes of a selected quaternary amine and a cyanide of Zn or Cd. An alkali metal hydroxide solution such as NaOH or KOH will quantitatively strip a pregnant extract of the quaternary ammonium complex of its metal and cyanide content and regenerate a quaternary ammonium hydroxide salt which can be used for extracting further metal cyanide values.

Self-grown oxy-hydroxide@ nanoporous metal electrode for high-performance supercapacitors.

PubMed

Kang, JianLi; Hirata, Akihiko; Qiu, H-J; Chen, LuYang; Ge, XingBo; Fujita, Takeshi; Chen, MingWei

2014-01-15

A binder-free self-grown oxy-hydroxide@nanoporous Ni-Mn hybrid electrode with high capacitance and cyclic stability is fabricated by electrochemical polarization of a dealloyed nanoporous Ni-Mn alloy. Combined with the low material costs, high electrochemical stability, and environmentally friendly nature, this novel electrode holds great promise for applications in high-capacity commercial supercapacitors. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Role of Water in Proton-Hydroxide Conductance Across Membranes

DTIC Science & Technology

1988-06-28

a~a,:v %~ ’ diffusion , rather than hopping along water wires, and there should be little or no deuterium effect. References Bangham , A.D...CONTRACT TITLE: Role of water in proton-hydroxide conductance across model and biological membranes. START DATE: October 1, 1987 RESEARCH OBJECTIVE: To...hypothesis of Bangham and Mason (1980) who suggested that general anesthetics might introduce defects into bilayers of synaptic vesicle membranes which lead

A One-Step Delamination Procedure to Form Single Sheet Iron(III)-(oxy)Hydroxides

EPA Science Inventory

The dispersion of a layered iron(III)-(oxy)hydroxide intercalated with dodecanoate (oxGR_C12, Fe₃^IIIO_2.18(OH)_3.13(C₁₂H₂₃O₂)_0.56(SO₄)_0.47; derived from the corr...