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Vocabulary Word

Word: catalyst

Definition: agent which brings about a chemical change while it remains unaffected and unchanged; CF. catalysis


Sentences Containing 'catalyst'

(Note: sulphur is not a true catalyst in gunpowder as it is consumed to a great extent into a variety of reaction products such as K2S.)
Although others had experimented with catalysts for this purpose, they were stymied by the fact that the catalyst ceased to work after a time.
Although this proved unsuccessful, it was the catalyst for a new Gateshead Thunder to be formed.
Ammonium metavanadate acts as a catalyst for various reactions.
Between 1987 and 1998, he was Director of Catalyst, a museum in Widnes, Cheshire on the chemical industry.
Both of these reactions make use of a palladium catalyst to carry out the coupling, while Sonogashira uses both palladium and copper catalysts simultaneously.
but nothing came of it until the 1970s because the tetraethyl lead that was still in use in the 1950s and 1960s poisoned the catalyst. Butadiene.
Catalyst is typically added to the mixture.
Coburn called Carson's work "junk science," proclaiming that "Silent Spring" "was the catalyst in the deadly worldwide stigmatization against insecticides, especially DDT."
Cu(I) is a co-catalyst in the reaction, and is used to increase the rate of the reaction.
Davis signed with the Carolina Panthers for the start of the 2003 NFL season, and was a catalyst in leading the team to Super Bowl XXXVIII.
During that time the industry used a nickel catalyst prepared from nickel(II) oxide.
Food and its nuances becomes a central character in the film, and acts as a catalyst of personal transformation.
I had an idea for a catalyst and it worked the first time."
In 1926 Raney produced a nickel-aluminium alloy, also in a 1:1 ratio, following a procedure similar to the one used for the nickel-silicon catalyst, and he found that the resulting catalyst was even more active than the previous one.
In 1950 he left Gilman Paint and founded the Raney Catalyst Company.
In industry, propanoic acid is mainly produced by the hydrocarboxylation of ethylene using nickel carbonyl as the catalyst: It is also produced by the aerobic oxidation of propionaldehyde.
In the case of gunpowder (a pressed composite without a polymeric binder) the fuel is charcoal, the oxidizer is potassium nitrate, and sulphur serves as a catalyst.
In the presence of sulfuric acid catalyst, the oxime rearranges to caprolactam, a precursor to nylon 6: Safety.
It can undergo alpha-halogenation with bromine in the presence of PBr3 as catalyst (the HVZ reaction) to form CH3CHBrCOOH.
It employs a palladium catalyst to form a carbon–carbon bond between a terminal alkyne and an aryl or vinyl halide.
It functions as a catalyst in certain reactions and is known to have toxic effects in certain species.
It has also been reported that gold can be used as a heterogeneous catalyst, which was demonstrated in the coupling of phenylacetylene and iodobenzene with an Au/CeO2 catalyst. In this case, catalysis occurs heterogeneously on the Au nanoparticles, with Au(0) as the active site.
It has been identified as a catalyst for "α-hydroxyphosphosphonate derivatives by the reaction of various aryl or heteroaryl aldehydes with triethylphosphonate derivatives".
It is hope that the development will have a positive effect acting as a catalyst for the local economy creating new jobs, homes and retail areas.
Later generations of the Walter Rocket used solid-state catalyst instead of its water solution.
Oxy-Catalyst. After World War II, Houdry formed the Oxy-Catalyst Company and turned his attention to reducing the health risks associated with the increasing amounts of automobile and industrial air pollution.
Platinum can be used as a catalyst to reduce the overpotential required for hydrogen production.
Several of Douglas' former girlfriends testified at the trial that he acted not just as an informer, but also as a catalyst and agent provocateur for the group's plans.
She has identified seeing singer and pianist Kate Bush perform her hit song "This Woman's Work" on television as a catalyst for her to pursue a music career.
Synthetic creatine is usually made from sarcosine (or its salts) and cyanamide which are combined in a reactor with catalyst compounds.
The actions of the "Enterprise"-C's crew became a catalyst for the alliance between the Federation and the Klingon Empire.
The assassination was a catalyst for the Rwandan Genocide.
The British were the catalyst for the ceasefire that ended the civil war.
The catalyst is the return of the power to the Well of Ascension.
The catalyst, which is continuously recycled and reused within the reactor, reduces the gasifier operating temperature.
The CDD mission is described as "To be the prime catalyst and facilitator for strategic analysis and capacity building for sustainable democracy and development in West Africa."
The center is a catalyst for the development, understanding, and advancement of simulation and defense technologies.
The choice of acid catalyst is very important.
The most significant catalyst behind new industry activity is the "Energy Policy Act of 2005".
The organisation serves as a catalyst to promote collaborative initiatives between manufacturers of digital audio recording and editing equipment.
The SCRs would use a catalyst and ammonia to react with NOx to form diatomic nitrogen and water.
The use of this catalyst/oxidizer combination is greener because it does not produce nitrogen oxides as do traditional ammoxidations.
They developed the process into fluid catalytic cracking, which solved the problem of having to shut down the process to burn the coke off the catalyst by using a continuously circulating fluidized catalyst made of a fine zeolite powder.
This battle served as the catalyst for the invention of the AK47.
This catalyst, now commonly known now as Raney nickel, was the subject of a patent he obtained in 1927.
This was an additional catalyst to African Americans' decisions to leave the South.
Ventures in Development is a non-profit organization that strives to be a catalyst in the creation of social enterprises in the Greater China region.
While at Yale, he began his entrepreneurial career as the co-founder of Catalyst Recruiting, an online forum for university students to network with potential employers.
While originally synthesized with mCPBA and the phase transfer catalyst benzyltrimethylammonium chloride, an improved synthesis using oxone as the oxidant is now most prevalent.

More Vocab Words

::: depose - dethrone; remove from office; give a deposition; testify
::: novelty - something new; newness; ADJ. novel: new; original
::: transpire - (of a fact) become known; be revealed; happen; give off (watery waste matter) through pores
::: pending - not yet decided or settled; impending; Ex. pending decision; PREP. while awaiting; until; Ex. delay the decision pending his return
::: anguish - acute pain; extreme suffering
::: amorphous - formless; lacking shape or definition
::: fauna - animals of a period or region; CF. flora
::: disarray - state of disorder; a disorderly or untidy state; Ex. with her clothes in disarray
::: imbalance - lack of balance or symmetry; disproportion
::: conveyance - vehicle; transfer; act of conveying; Ex. public conveyance