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Sunday, August 1, 2021

08-01-2021-0236 - demeton pesticides; electrolysis (potas, sulph, acids) - Ylide Amines

PESTICIDE RESIDUES IN FOOD - 1984 Sponsored jointly by FAO and WHO EVALUATIONS 1984 The monographs Data and recommendations of the joint meeting of the FAO Panel of Experts on Pesticide Residues in Food and the Environment and the WHO Expert Group on Pesticide Residues Rome, 24 September - 3 October 1984 Food and Agriculture Organization of the United Nations Rome 1985 DEMETON-S-METHYL SULFONE EVALUATION FOR ACCEPTABLE DAILY INTAKE BIOCHEMICAL ASPECTS Absorption, Distribution and Excretion
http://www.inchem.org/documents/jmpr/jmpmono/v84pr52.htm

LANCET
TOXIC EFFECTS OF DIAMINODIPHENYL-SULPHONE IN TREATMENT OF LEPROSY
ElizabethJ. Allday, M.B. Lond.
J. Barnes, M.D. N.U.I.
Published:August 04, 1951DOI:https://doi.org/10.1016/S0140-6736(51)91443-2
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(51)91443-2/fulltext


On the Electrolysis of Potassium Ethyl-Sulphone-Acetate
Published online by Cambridge University Press: 15 September 2014
Crum Brown and
Herbert W. Bolam

https://www.cambridge.org/core/journals/proceedings-of-the-royal-society-of-edinburgh/article/abs/div-classtitleon-the-electrolysis-of-potassium-ethyl-sulphone-acetatediv/50416D91CD0977A9AB8E55B2243D0445


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Organic Compounds of Sulphur, Selenium, and Tellurium: Volume 3
https://books.google.com/books?
id=enAoDwAAQBAJ&pg=PA357&lpg=PA357&dq=SULPHENE&source=bl&ots=BSe0yO5RTu&sig=ACfU3U1LgOn_G45mYV92DO_MbPB9JwU77g&hl=en&sa=X&ved=2ahUKEwjL27HPmo_yAhWRbc0KHa8tBWI4HhDoATAIegQIChAD#v=onepage&q=SULPHENE&f=false

Sulphone Treatment of Leprosy

Br Med J 19471 doi: https://doi.org/10.1136/bmj.1.4509.798 (Published 07 June 1947)Cite this as: Br Med J 1947;1:798https://www.bmj.com/content/1/4509/798

Density functional calculations show that the barrier to ring closure of ammonium betaines is significantly higher than the same process for sulfoniumbetaines,83 rationalizing the differing reactivity (and explaining why hydroxy ammonium salts are isolated from reactions of carbonyls and ammonium ylides at low temperature84).
https://www.sciencedirect.com/topics/chemistry/ammonium-ylide

Synthetic Reactions of M=C and M=N Bonds: Ylide Formation, Rearrangement, and 1,3-Dipolar Cycloaddition☆

J. Wang, Y. Zhang, in Reference Module in Chemistry, Molecular Sciences and Chemical Engineering, 2013

[1,2]-Shift (Stevens Rearrangement) and Related Reactions

Ammonium ylides undergo [1,2]-shift in manner similar to oxonium and sulfonium ylides. A preferentially migrating group is usually a benzyl group. A sequence of intramolecular formation of ammonium ylide and subsequent rearrangement was extensively explored by West and co-workers in synthesis of cyclic amines.95 Rh2(OAc)4-catalyzed reaction of diazoketone 273 gave ammonium ylide 274, which undergoes [1,2]-shift to give piperidine derivatives 275 (eqn [40]).95 In this case, the migrating group is CH2C6H5, CO2Et and p-XC6H4. When X is MeO or Ac, homocoupling product 276 is also isolated in 19% or 25% yield, respectively. Formation of the homocoupling products is a strong evidence that the [1,2]-shift proceeds through a radical pair intermediate.18

https://www.sciencedirect.com/topics/chemistry/ammonium-ylide


Ylide Addition

Sometimes, nucleophiles adding to a carbonyl do not follow the normal reactivity patterns that have been common so far. This is often the case with the addition of ylides. Ylides are compounds that are often depicted with a positive charge one one atom and a negative charge on the next atom. They are examples of zwitterions, compounds that contain both positive and negative charges within the same molecule. What distinguishes them from other zwitterions is the proximity of the opposite charges.

The classic example of an ylide addition to a carbonyl is the Wittig reaction, which involves the addition of a phosphorus ylide to an aldehyde or ketone. Rather than producing an alcohol, the reaction produces and alkene. The reaction is driven by formation of a phosphorus oxide "side product".


https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Reactions/Addition_Reactions/Addition_to_Carbonyls/Ylide_Addition


The classic example of an ylide addition to a carbonyl is the Wittig reaction, which involves the addition of a phosphorus ylide to an aldehyde or ketone. Rather than producing an alcohol, the reaction produces and alkene. The reaction is driven by formation of a phosphorus oxide "side product".

This is a special case. The phosphorus-oxygen bond is strong enough to change the course of this reaction away from the normal pattern, and it isn't something you would have been able to predict based on related reactions.

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Reactions/Addition_Reactions/Addition_to_Carbonyls/Ylide_Addition

Once the phosphonium salt has been made, the phosphorus ylide can then be obtained via deprotonation of a phosphonium ion. The hydrogens on a carbon next to a phosphorus cation are a little bit acidic because of the positive charge on the phosphorus. One of these hydrogens is easily removed via adddition of a very strong base such as sodium hydride.

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Reactions/Addition_Reactions/Addition_to_Carbonyls/Ylide_Addition

Show, with reaction arrows, formation of ylides from the three alkyltriphenyl phosphonium bromide salts shown above in Problem CO18.1.

The reaction of a phosphorus ylide with a carbonyl compound does begin like other nucleophilic additions. The ylide donates its nucleophilic lone pair to the carbonyl and the carbonyl pi bond breaks. However, the strong P-O bond then takes over the reaction. To begin, a lone pair on the resulting alkoxide ion is donated to the positively charged phosphonium ion.

Wait! That violates one of our mechanistic rules. Usually, we don't have an atom donate to a positively charged atom that already has an octet; if we do so, the atom will have too many electrons. However, the octet rule doesn't strictly apply to sulfur and phosphorus. These atoms are larger than second-row atoms like nitrogen and oxygen, and they are often observed to "exceed the octet rule". Sulfur and phosphorus are frequently observed with trigonal bipyramidal or octahedral molecular geometries, meaning they may have up to 12 electrons in their valence shells.

So go ahead! Donate a pair of electrons to the phosphorus. It can't help itself, because of the strength of the P-O bond that forms.

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Reactions/Addition_Reactions/Addition_to_Carbonyls/Ylide_Addition



08-01-2021-0233 - Brequinar sodium draft



Transplant Proc

. 1996 Apr;28(2):960-3.
Brequinar sodium
D V Cramer 1
Affiliations expand
PMID: 8623481

Abstract

The future use of BQR as a component of a treatment regimen for preventing graft rejection is uncertain. The drug exhibits a number of characteristics that are considered desirable for inclusion in a multidrug antirejection protocol. BQR is an effective immunosuppressive agent and can act as a single agent to prevent the rejection of allografts and xenografts. Its immunosuppressive activity is especially useful in those situations for which inhibition of antibody production is an important objective of the treatment protocol...

https://pubmed.ncbi.nlm.nih.gov/8623481/
Eur J Med Chem

. 2020 Dec 1;207:112705. doi: 10.1016/j.ejmech.2020.112705. Epub 2020 Aug 22.
Diphenyl triazine hybrids inhibit α-synuclein fibrillogenesis: Design, synthesis and in vitro efficacy studies
Mudasir Maqbool 1, Joshna Gadhavi 2, Pravin Hivare 2, Sharad Gupta 3, Nasimul Hoda 4
Affiliations expand
PMID: 32961434
DOI: 10.1016/j.ejmech.2020.112705

https://pubmed.ncbi.nlm.nih.gov/32961434/

Curr Pharm Des

. 2013;19(8):1528-48.
Privileged scaffolds or promiscuous binders: a glance of pyrrolo[2,1-f][1,2,4]triazines and related bridgehead nitrogen heterocycles in medicinal chemistry
Yu'ning Song 1, Peng Zhan, Qingzhu Zhang, Xinyong Liu
Affiliations expand
PMID: 23131184
https://pubmed.ncbi.nlm.nih.gov/23131184/

Review
Biopolymers

. 2000;55(2):140-64.doi: 10.1002/1097-0282(2000)55:2<140::AID-BIP40>3.0.CO;2-B.
Triazine-based condensing reagents
Z J Kamiński 1
Affiliations expand
PMID: 11074411
DOI: 10.1002/1097-0282(2000)55:2<140::AID-BIP40>3.0.CO;2-B

Abstract

The synthesis, properties, and application of condensing reagents derived from 1,3,5-triazines are described. The mechanism of activation of carboxylic function, structure of reactive intermediates, and mechanism of acylation of nucleophiles are presented. The synthetic versatility of mono- and bifunctional reagents for syntheses in solution, triazine-based immobilized reagents, chiral triazines for enantiodifferentiating syntheses, are discussed. The scope and limitation of the synthetic utility of triazine reagents in the preparation of heterocyclic compounds, amides, esters, oligopeptides-including large-scale syntheses and use in the combinatorial chemistry-is demonstrated.

Similar articles
Synthesis and application of chiral triazine condensing reagents prepared from esters of amino acids.
Kamiński ZJ, Zajac KJ, Jastrzabek K.Acta Biochim Pol. 2001;48(4):1143-6.PMID: 11995981
N-triazinylammonium tetrafluoroborates. A new generation of efficient coupling reagents useful for peptide synthesis.
Kamiński ZJ, Kolesińska B, Kolesińska J, Sabatino G, Chelli M, Rovero P, Błaszczyk M, Główka ML, Papini AM.J Am Chem Soc. 2005 Dec 7;127(48):16912-20. doi: 10.1021/ja054260y.PMID: 16316237
https://pubmed.ncbi.nlm.nih.gov/11074411/

Pharmazie

. 2001 Apr;56(4):275-86.
Chemistry of uncondensed 1,2,4-triazines, Part IV. Synthesis and chemistry of bioactive 3-amino-1,2,4-triazines and related compounds--an overview
R M Abdel-Rahman 1
Affiliations expand
PMID: 11338663

Abstract

Studies on the chemical reactivity of bioactive 3-amino-1,2,4-triazines are reviewed. The synthesis, unique features and pharmacological significance of these constituents are discussed.

https://pubmed.ncbi.nlm.nih.gov/11338663/
Molecules

. 2020 Nov 23;25(22):5475. doi: 10.3390/molecules25225475.
1,3,5-Triaryl-1,3,5-Triazinane-2,4,6-Trithiones: Synthesis, Electronic Structure and Linear Optical Properties
Ismaël Rabouel 1, Nicolas Richy 1, Anissa Amar 2 3, Abdou Boucekkine 1, Thierry Roisnel 1, Olivier Mongin 1, Mark G Humphrey 4, Frédéric Paul 1
Affiliations expand
PMID: 33238454
PMCID: PMC7700228
DOI: 10.3390/molecules25225475Free PMC article

Abstract

The synthesis of four new 1,3,5-triaryl-1,3,5-triazinane-2,4,6-trithione derivatives (thioisocyanurates) and two new partially thionated analogues from the corresponding 1,3,5-triaryl-1,3,5-triazinane-2,4,6-triones (isocyanurates) is reported, together with their spectroscopic properties. DFT calculations and comparison with the corresponding isocyanurates evidence the impact of the oxygen-for-sulfur replacement on the electronic structure and linear optical properties of these heterocycles. A bathochromic shift of the absorption bands and more efficient quenching of the fluorescence was observed.

Keywords: DFT calculations; cyclic thioureas; cyclic urea; isocyanurates; linear optics; thioisocyanurates; thionation.

https://pubmed.ncbi.nlm.nih.gov/33238454/

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Synthesis, Characterization, and Biological Evaluation of Novel 7-Oxo-7H-thiazolo[3,2-b]-1,2,4-triazine-2-carboxylic Acid Derivatives.
Cai D, Li T, Xie Q, Yu X, Xu W, Chen Y, Jin Z, Hu C.Molecules. 2020 Mar 13;25(6):1307. doi: 10.3390/molecules25061307.PMID: 32182992 Free PMC article.

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o-Carboranylalkoxy-1,3,5-Triazine Derivatives: Synthesis, Characterization, X-ray Structural Studies, and Biological Activity.
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Mirallai SI, Koutentis PA, Aldabbagh F.Molecules. 2019 Jan 14;24(2):282. doi: 10.3390/molecules24020282.PMID: 30646524 Free PMC article.

https://pubmed.ncbi.nlm.nih.gov/?term=%22Triazines%2Fchemistry%22%5BMAJR%5D

Divinyl sulphone


https://webbook.nist.gov/cgi/cbook.cgi?ID=77-77-0

Basal metabolic rate

From Wikipedia, the free encyclopedia
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Basal metabolic rate (BMR) is the rate of energy expenditure per unit time by endothermic animals at rest.[1] It is reported in energy units per unit time ranging from watt (joule/second) to ml O2/min or joule per hour per kg body mass J/(h·kg). Proper measurement requires a strict set of criteria be met. These criteria include being in a physically and psychologically undisturbed state, in a thermally neutral environment, while in the post-absorptive state(i.e., not actively digesting food).[1] In bradymetabolic animals, such as fish and reptiles, the equivalent term standard metabolic rate (SMR) is used. It follows the same criteria as BMR, but requires the documentation of the temperature at which the metabolic rate was measured. This makes BMR a variant of standard metabolic rate measurement that excludes the temperature data, a practice that has led to problems in defining "standard" rates of metabolism for many mammals.[1]

Metabolism comprises the processes that the body needs to function.[2] Basal metabolic rate is the amount of energy per unit of time that a person needs to keep the body functioning at rest. Some of those processes are breathingblood circulation, controlling body temperaturecell growth, brain and nerve function, and contraction of muscles. Basal metabolic rate affects the rate that a person burns calories and ultimately whether that individual maintains, gains, or loses weight. The basal metabolic rate accounts for about 60 to 75% of the daily calorie expenditure by individuals. It is influenced by several factors. BMR typically declines by 1–2% per decade after age 20, mostly due to loss of fat-free mass,[3] although the variability between individuals is high.[4]


https://en.wikipedia.org/wiki/Basal_metabolic_rate


Pantoprazole sulphone
https://www.carbosynth.com/carbosynth/website.nsf/(w-productdisplay)/D7E89FC086AE4BD380257DB700407AE3

Photochemical Synthesis

5. SULPHENES AS PHOTOCHEhlICAL INTERMEDIATES1

J.F.KING,P.DE ~'IAToE,.A'IORKVEDA,.~B.hl.A.SATTARA,ND A.STOESSL~ Department of Chemistry, Univeisity of Western Ontavio, London, Ontario

Received August 23, 1962

ABSTRACT

The present status of sulphenes (RIR"C:SO~)as stable entities or chemical intermediates is discussed. The early report by Locher and Fierz (Helv. Chitn. Acta, 10, 642 (1927)) of the preparation of a stable crystalline sulphene has been investigated; it is concluded that their claim is unfounded.

The irradiation of unsaturated sultones in the presence of methanol is shown to give sul- phonic esters: the corresponding thermal reaction of sultones is known to lead to sulphonic acid derivatives. It is proposed that the irradiation of unsaturated sultones yields sulphenes, which then react with the medium

https://cdnsciencepub.com/doi/pdf/10.1139/v63-012

Titanium sulphene: two-dimensional confinement of electrons and phonons giving rise to improved thermoelectric performance.

We investigated the thermoelectric properties of titanium sulphene, namely, few-layered TiS(2) nanosheets, by using density functional theory and the Boltzmann transport equations. The Seebeck coefficient of titanium sulphene was found to increase if the thickness fell below 14 triple layers (~8 nm) and for the monolayer becomes 40% larger than that of the bulk TiS(2). This behavior is attributed to an enhancement in the density of states near the conduction band minimum in the monolayer. Moreover, the acoustic phonon band of the monolayer is more flat than that of the bulk, which results in a 37% reduction of the acoustic phonon group velocity and was beneficial for a low lattice thermal conductivity. Therefore, the combined effects from quantum confinement of both electrons and phonons could lead to a significant enhancement in thermoelectric performance in the two-dimensional titanium sulphene. Collapse


https://www.semanticscholar.org/paper/Titanium-sulphene%3A-two-dimensional-confinement-of-Zhang-Wan/959fb9c498f0ff17fc5a8571d0541aa00aaeb85b

 Oldenbourg Wissenschaftsverlag January 19, 2021

Interaction of sulphone based reactive dyes with cationic surfactant: a spectroscopic and conductometric study

Misbah IramHamadia SultanaMuhammad UsmanBazgha AhmadNadia AkramMuhammad Siddiq and Sadaf Rashid
    https://www.degruyter.com/document/doi/10.1515/zpch-2020-1706/html

    Poly(p-phenylene ether-sulphone)

    Catalog #: 391
    https://scipoly.com/shop/polyp-phenylene-ether-sulphone-3/




    08-01-2021-0221 - draft - Treatment of leprosy with diamino-diphenyl sulphone by mouth



    n Tuberc Other Mycobact Dis

    . 2021 May 8;24:100244. doi: 10.1016/j.jctube.2021.100244.eCollection 2021 Aug.
    Approach to the diagnosis and treatment of non-tuberculous mycobacterial disease
    Kelly M Pennington 1, Ann Vu 1, Douglas Challener 2, Christina G Rivera 3, F N U Shweta 2, John D Zeuli 3, Zelalem Temesgen 2
    Affiliations expand
    PMID: 34036184
    PMCID: PMC8135042
    DOI: 10.1016/j.jctube.2021.100244Free PMC article

    Abstract

    Non-tuberculous mycobacteria (NTM) is a collective name given to a group of more than 190 species of Mycobacterium. The clinical presentation for most NTM infections is non-specific, often resulting in delayed diagnosis. Further complicating matters is that NTM organisms can be difficult to isolate. Medications used to treat NTM infection can be difficult for patients to tolerate, and prolonged courses of anti-mycobacterial therapy are often required for adequate suppression or eradication. Herein, we review different NTM syndromes, appropriate diagnostic tests, and treatment regimens.

    Keywords: ADR, adverse drug reactions; AFB, acid fast bacilli; AST, antimicrobial-susceptibility testing; ATS, American Thoracic Society; BCG, Bacille Calmette-Guerin; CLSI, Clinical and Laboratory Standards Institute; COPD, chronic obstructive pulmonary disease; ECG, electrocardiogram; EMB, ethambutol; Erm, erythromycin ribosomal methylase; FDA, Food and Drug Administration; HIV, human immunodeficiency virus; HRCT, high resolution computed tomography; IDSA, Infectious Disease Society of America; INF-γ, interferon- γ; INH, isoniazid; MAC, Mycobacterium avium complex; MALDI-TOF, matrix-assisted laser desorption ionization time-of-flight mass spectrometry; MGIT, mycobacteria growth indicator tube; MIC, minimum inhibitory concentrations; Mycobacterium abscessus; Mycobacterium avium; NTM, non-tuberculous mycobacteria; Non-tuberculous mycobacteria; PCR, polymerase chain reaction; PFT, pulmonary function test; TB, tuberculosis; TDM, therapeutic drug monitoring.

    © 2021 The Authors. Published by Elsevier Ltd.

    https://pubmed.ncbi.nlm.nih.gov/34036184/

    Lancet

    . 1950 Jan 28;1(6596):145-50. doi: 10.1016/s0140-6736(50)90257-1.
    Treatment of leprosy with diamino-diphenyl sulphone by mouth
    J LOWE
    PMID: 15401496
    DOI: 10.1016/s0140-6736(50)90257-1
    No abstract available
    https://pubmed.ncbi.nlm.nih.gov/15401496/

    08-01-2021-0218 - Sulphene–tertiary amine zwitterions: intermediates in the multiexchange of hydrogen in a sulphene reaction

     Issue 23, 1972


    Sulphene–tertiary amine zwitterions: intermediates in the multiexchange of hydrogen in a sulphene reaction 

    Abstract

    With sterically unhindered tertiary amines and deuterium oxide or other deuteriated sulphene traps, alkanesulphonyl halides with more than one α-hydrogen may yield products having more than one of the α-hydrogens exchanged; evidence is presented for a mechanism involving reaction of the intermediate sulphene with the amine to form a zwitterion ([graphic omitted]HR1SO2[graphic omitted]R32) which may then exchange hydrogens viaits conjugate acid.


    https://pubs.rsc.org/en/content/articlelanding/1972/C3/C39720001313

    08-01-2021-0216 - draft sulphone

     

    sulphone


    QUICK REFERENCE

    n. one of a group of drugs closely related to the sulphonamides in structure and therapeutic actions. Sulphones possess powerful activity against the bacteria that cause leprosy and tuberculosis. The best known sulphone is dapsone.

    https://www.oxfordreference.com/view/10.1093/oi/authority.20110803100541579



    08-01-2021-0210 - Methyl vinyl sulphone: a new class of Michael-type genotoxin 1990



    . 1990 Nov;245(3):191-9. doi: 10.1016/0165-7992(90)90049-p.
    Methyl vinyl sulphone: a new class of Michael-type genotoxin
    T J Warr 1, J M Parry, R D Callander, J Ashby
    Affiliations expand
    PMID: 2233840
    DOI: 10.1016/0165-7992(90)90049-p

    Abstract


    Methyl vinyl sulphone (MVS) is a labile, Michael-reactive chemical, similar in structure to acrylamide (AA). Given that acrylamide is a reference mammalian mutagen and a rodent carcinogen, studies were undertaken to evaluate the potential genotoxicity of MVS. In common with AA, MVS was non-mutagenic to Salmonella but active as an aneugen to cultured mammalian cells. It is concluded that vinyl sulphones should be regarded as representative of a new class of genotoxic chemical whose mode of action is probably primarily dependent upon Michael reactivity to proteins.
    https://pubmed.ncbi.nlm.nih.gov/2233840/
    Notes and references[edit]

    ^ "hertz". (1992). American Heritage Dictionary of the English Language(3rd ed.), Boston: Houghton Mifflin.
    ^ "SI Brochure: The International System of Units (SI) § 2.3.1 Base units" (PDF) (in English and French) (9th ed.). BIPM. 2019. p. 130. Retrieved 2 February 2021.
    ^ "SI Brochure: The International System of Units (SI) § Appendix 1. Decisions of the CGPM and the CIPM" (PDF) (in English and French) (9th ed.). BIPM. 2019. p. 169. Retrieved 2 February 2021.
    ^ Mohr, J. C.; Phillips, W. D. (2015). "Dimensionless Units in the SI". Metrologia. 52 (1): 40–47. arXiv:1409.2794. Bibcode:2015Metro..52...40M. doi:10.1088/0026-1394/52/1/40. S2CID 3328342.
    ^ Mills, I. M. (2016). "On the units radian and cycle for the quantity plane angle". Metrologia. 53 (3): 991–997. Bibcode:2016Metro..53..991M. doi:10.1088/0026-1394/53/3/991.
    ^ "SI units need reform to avoid confusion". Editorial. Nature. 548(7666): 135. 7 August 2011. doi:10.1038/548135b. PMID 28796224.
    ^ P. R. Bunker; I. M. Mills; Per Jensen (2019). "The Planck constant and its units". J Quant Spectrosc Radiat Transfer. 237: 106594. Bibcode:2019JQSRT.23706594B. doi:10.1016/j.jqsrt.2019.106594.
    ^ NIST Guide to SI Units – 9 Rules and Style Conventions for Spelling Unit Names, National Institute of Standards and Technology
    ^ "(d) The hertz is used only for periodic phenomena, and the becquerel (Bq) is used only for stochastic processes in activity referred to a radionuclide." "BIPM – Table 3". BIPM. Retrieved 24 October 2012.
    ^ "SI brochure, Section 2.2.2, paragraph 6". Archived from the original on 1 October 2009.
    ^ "IEC History". Iec.ch. Retrieved 6 January 2021.
    ^ Cartwright, Rufus (March 1967). Beason, Robert G. (ed.). "Will Success Spoil Heinrich Hertz?" (PDF). Electronics Illustrated. Fawcett Publications, Inc. pp. 98–99.
    ^ Pellam, J. R., & Galt, J. K. (1946). Ultrasonic propagation in liquids: I. Application of pulse technique to velocity and absorption measurements at 15 megacycles. The journal of chemical physics, 14(10), 608-614.
    ^ Ernst Terhardt (20 February 2000). "Dominant spectral region". Mmk.e-technik.tu-muenchen.de. Archived from the original on 26 April 2012. Retrieved 28 April 2012.
    ^ "Black Hole Sound Waves - Science Mission Directorate". science.nasa.go.
    ^ Atomic vibrations are typically on the order of tens of terahertz
    ^ "Black Hole Sound Waves - Science Mission Directorate". science.nasa.go.
    ^ Asaravala, Amit (30 March 2004). "Good Riddance, Gigahertz". Wired. Retrieved 28 April 2012.
    ^ Unicode Consortium (2019). "The Unicode Standard 12.0 – CJK Compatibility ❰ Range: 3300—33FF ❱" (PDF). Unicode.org. Retrieved 24 May 2019.



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