nuclear magnetic resonance spectroscopy - 2026 ACF Regionals

Packet F: Tossup 1

The sensitivity of this technique is improved by employing CryoProbes with continuous liquid helium streams. (10[1])The DISPEL method is applied during this technique to remove “satellites” shouldering primary signals. Chromium(III) acac (“ay-cack”) is used in this technique as a relaxation agent for (10[1])more (10[1])rapid scans. (10[2])One type of this technique (-5[1])applies 45-, 90-, and 135-degree (10[3])pulses (10[3])on the sample (10[6]-5[1])to induce (10[2])polarization (10[2]-5[1])transfer. (10[2]-5[1])Through-space (10[1])interactions are probed (10[1])by measuring the Overhauser (10[1])effect (10[1])in this technique, (10[4])one form of (10[1])which (10[1])requires concentrated samples due to the (-5[1])low one percent abundance of a natural isotope. (10[2]-5[1])Proton decoupling (10[2]-5[1])generates (10[2])singlet (10[2])peaks (10[2])with no (10[2])splitting (10[5])in this technique’s (10[4])13C (-5[1])variant. (10[6]-5[4])For (0[1])10 (10[1]-5[1])points, (10[2])name this (-5[1])analytical technique that applies a magnetic (10[1]-5[1])field on a sample. (10[1])■END■ (10[11]0[7])

ANSWER: nuclear magnetic resonance spectroscopy [or NMR spectroscopy; accept carbon NMR or carbon-13 NMR or 13C NMR; accept proton NMR or 1H NMR; accept 1-dimensional NMR or 2-dimensional NMR; accept nuclear Overhauser effect spectroscopy or NOE spectroscopy or NOESY until “Overhauser” is read; prompt on spectroscopy; prompt on pulsing or polarization transfer or DEPT until read by asking “what larger technique is that a part of?”]

<McGill C, Chemistry> | Packet F - Chicago C, McGill C, WashU A, Chicago B

= Average correct buzzpoint

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Buzzes

Player	Team	Opponent	Buzzpoint	Value
Davin Sivertson	Alabama B	Louisville B	14	10
Andrew Wang	Illinois A	Illinois B	40	10
Calvin Bostleman	Ohio State A	Michigan C	41	10
Mason Yu	Brown	MIT	43	10
Matthew He	Texas A	Murray State A	43	10
Hiten Umarnani	Imperial C	City St. George's	48	-5
Danny Han	Stanford B	Berkeley C	53	10
Karthik Jayaram	UCLA A	Arizona State	53	10
Caleb Ott	Waterloo A	Ottawa	53	10
Swapnil Garg	Berkeley A	Stanford A	54	10
Russell Nip	UBC A	Western A	54	10
Delia Cropper	Oxford A	Cambridge B	54	10
Andrew Nucci	UCLA B	UCSD A	57	10
Jay Misuk	Western C	McGill B	57	-5
Seth Allen	McMaster A	Toronto F	57	10
S. A. Shenoy	Georgia Tech D	Tennessee B	57	10
Oscar Despard	Cambridge A	Edinburgh A	57	10
Eugenia Tong	Imperial A	Bristol	57	10
Ben Hellman	Swarthmore	Rutgers A	57	10
Kevin Ye	Simon Fraser	Queen's	59	10
Ethen Sun	Toronto D	Toronto C	59	10
Azura Gollamudi	Northwestern B	Notre Dame A	60	10
Oliver West	Cambridge C	Oxford B	60	10
Eli O'Sick Johnson	Binghamton B	Binghamton A	60	-5
Rohan Dalal	Georgia Tech A	Washington B	61	-5
Matthew Sumanen	Georgia Tech C	Kentucky	61	10
Aisling Skeet	Durham	LSE	61	10
Jason Zhang	Toronto B	Carleton University	62	10
Alex Akridge	Indiana A	Purdue B	65	10
Rachel Fanous	Michigan B	Michigan A	69	10
Shiva Tegulla	Central Florida A	Florida B	70	10
Vinu Harihar	Berkeley B	Berkeley D	73	10
Jaiden Li	UCSD B	UCSD C	73	10
Jerry Vinokurov	John Jay	Columbia C	73	10
Ryan Rosenberg	NYU A	Rutgers B	73	10
Sinecio Morales	Johns Hopkins A	Maryland B	76	10
Jack Lewis	Bruin	Alabama A	77	10
Braden Booth	Missouri A	Minnesota A	83	-5
Thomas Tibbetts	Central Florida C	Florida C	91	-5
Danny Fisher	Warwick B	Cardiff	91	10
Rachel Bentham	Manchester	Warwick A	91	10
Brodrick Tastad	VCU	James Madison B	93	-5
Nathan Long	Imperial B	Birmingham	93	10
Olin Bose	Columbia B	NYU C	93	10
Aditya Patnaik	Ohio State B	CWRU A	94	10
Ted Harrison	Edinburgh B	UCL	94	10
Timothy Chiu	Northwestern D	Illinois C	95	10
Moses Kitakule	Columbia A	Georgetown	95	10
Ilyas Choukri	Virginia Tech A	Liberty B	96	10
Tianyu Xu	Georgia Tech B	WashU B	96	10
Ashlee Bacconi	UC Santa Barbara	UC Irvine	98	10
Nick Smemoe	North Carolina A	William and Mary	98	10
Jason Thieu	Michigan State	Pittsburgh	99	10
Jackson Price	Dartmouth B	Brandeis A	99	10
Annika Larson	Claremont	Washington A	99	10
Drew Wetterlind	Iowa State	Missouri B	99	10
Joel Dicker	Southampton B	Oxford C	99	10
Yusuf Baig	McMaster B	Brock	102	10
Cooper Stringer	Northwestern C	Chicago E	102	10
Eric Yang	Purdue A	Indiana C	102	10
Michael Wu	Southampton A	Montpellier	102	10
Samanyu Dixit	North Carolina C	South Carolina B	103	-5
Dawson Teu	Waterloo B	Guelph	104	10
Jesse Mindel	NC State A	Duke	104	10
Mason Lambert	James Madison A	Virginia Tech B	104	-5
Liam Rojas	Virginia	NC State B	104	10
Ezra Santos	Chicago A	Indiana B	104	-5
Matthew Forster	Dartmouth A	Southern Connecticut State	104	-5
Snehan Saroch	Louisville A	Mississipi State	104	-5
Kelvin Ni	NYU B	Maryland C	104	10
Alec Riso	Cornell A	Cornell C	104	10
Cade Reinberger	RIT	Penn State	104	10
Ella Tang	McGill B	Western C	105	0
James Watson	Wake Forest	South Carolina A	106	-5
Benny Shtutman	South Carolina A	Wake Forest	106	10
Yixi Yang	Yale	Bowdoin B	107	10
Simarya Ahuja	Washington B	Georgia Tech A	107	10
Jacob Goodson	Ohio State C	CWRU B	109	-5
Aiden Bang	Johns Hopkins B	Vassar	115	-5
Robert Chen	Rochester	Cornell B	115	10
Rohan Ganeshan	Harvard A	Brandeis B	119	10
AnnaMaria Donnelly	Central Florida B	Florida A	120	0
Avishka Fulgavkar	Florida A	Central Florida B	120	0
Khanh Nguyen	Florida C	Central Florida C	120	10
Wyatt Johnson	CWRU B	Ohio State C	120	10
Emily Kadolph	Virginia Tech B	James Madison A	120	10
Summer Solis	James Madison B	VCU	120	0
Josh Schmidt	Liberty A	Liberty C	120	10
Kabir Zaman	South Carolina B	North Carolina C	120	10
Nermeen Rahman	Indiana B	Chicago A	120	10
Dustin Sanders	Chicago D	Notre Dame B	120	10
Christopher Bradley	Southern Connecticut State	Dartmouth A	120	10
Wren Horne	Harvard B	Bowdoin A	120	10
Foster Hughes	Minnesota A	Missouri A	120	10
Veer Vanmali	Mississipi State	Louisville A	120	0
Katie Farthing	Vanderbilt B	Sewanee	120	0
Zach Foster	City St. George's	Imperial C	120	0
Ezra Siegartel	Vassar	Johns Hopkins B	120	10
Andrew Miller	Binghamton A	Binghamton B	120	0

Summary

Tournament	Edition	Match	Heard	Conv. %	Neg %	Avg. Buzz
California (North)	Main Site	✓	3	100%	0%	60.00
California (South)	Main Site	✓	4	100%	0%	70.25
Canada	Main Site	✓	10	80%	10%	68.75
Florida	Main Site	✓	3	67%	33%	95.00
Great Lakes	Main Site	✓	5	100%	20%	84.60
Lower Mid-Atlantic	Main Site	✓	9	89%	44%	108.50
Midwest	Main Site	✓	8	100%	13%	88.00
Northeast	Main Site	✓	6	100%	17%	101.33
Overflow	Main Site	✓	4	100%	50%	106.25
South Central	Main Site	✓	2	50%	0%	43.00
Southeast	Main Site	✓	7	71%	14%	61.00
UK	Main Site	✓	12	92%	8%	78.09
Upper Mid-Atlantic	Main Site	✓	8	100%	13%	86.38
Upstate NY	Main Site	✓	4	75%	25%	107.67