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  • richardmitnick 12:59 pm on September 18, 2021 Permalink | Reply
    Tags: "Scientists demonstrate pathway to forerunner of rugged nanotubes that could lead to widespread industrial fabrication", , , , , , , , Quantum Chemistry   

    From DOE’s Princeton Plasma Physics Laboratory (US) at Princeton University (US) : “Scientists demonstrate pathway to forerunner of rugged nanotubes that could lead to widespread industrial fabrication” 

    From DOE’s Princeton Plasma Physics Laboratory (US)

    at

    Princeton University

    Princeton University (US)

    September 16, 2021
    John Greenwald

    1
    Author and co-authors with figure from paper. Clockwise from top left: Lead author Yuri Barsukov with co-authors Igor Kaganovich, Alexander Khrabry, Omesh Dwivedi, Sierra Jubin, Stephane Ethier. Credits: Batalova Valentina, Elle Starkman/Office of Communications, Elle Starkman, Han Wei, Hannah Smith, Elle Starkman. Collage by Elle Starkman.

    Scientists have identified a chemical pathway to an innovative insulating nanomaterial that could lead to large-scale industrial production for a variety of uses – including in spacesuits and military vehicles. The nanomaterial — thousands of times thinner than a human hair, stronger than steel and noncombustible — could block radiation to astronauts and help shore up military vehicle armor, for example.

    Collaborative researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have proposed a step-by-step chemical pathway to the precursors of this nanomaterial, known as boron nitride nanotubes (BNNT), which could lead to their large-scale production.

    “Pioneering work”

    The breakthrough brings together plasma physics and quantum chemistry and is part of the expansion of research at PPPL. “This is pioneering work that takes the Laboratory in new directions,” said PPPL physicist Igor Kaganovich, principal investigator of the BNNT project and co-author of the paper that details the results in the journal Nanotechnology.

    Collaborators identified the key chemical pathway steps as the formation of molecular nitrogen and small clusters of boron, which can chemically react together as the temperature created by a plasma jet cools, said lead author Yuri Barsukov of The Peter the Great St.Petersburg Polytechnic University [Санкт-Петербургский политехнический университет Петра Великого](RU). He developed the chemical reaction pathways by performing quantum chemistry simulations with the assistance of Omesh Dwivedi, a PPPL intern from Drexel University (US), and Sierra Jubin, a graduate student in the Princeton Program in Plasma Physics.

    The interdisciplinary team included Alexander Khrabry, a former PPPL researcher now at The DOE’s Lawrence Livermore National Laboratory (US) who developed a thermodynamic code used in this research, and PPPL physicist Stephane Ethier who helped the students compile the software and set up the simulations.

    The results solved the mystery of how molecular nitrogen, which has the second strongest chemical bond among diatomic, or double-atom molecules, can nonetheless break apart through reactions with boron to form various boron-nitride molecules, Kaganovich said. “We spent considerable amount of time thinking about how to get boron – nitride compounds from a mixture of boron and nitrogen,” he said. “What we found was that small clusters of boron, as opposed to much larger boron droplets, readily interact with nitrogen molecules. That’s why we needed a quantum chemist to go through the detailed quantum chemistry calculations with us.”

    BNNTs have properties similar to carbon nanotubes, which are produced by the ton and found in everything from sporting goods and sportswear to dental implants and electrodes. But the greater difficulty of producing BNNTs has limited their applications and availability.

    Chemical pathway

    Demonstration of a chemical pathway to the formation of BNNT precursors could facilitate BNNT production. The process of BNNT synthesis begins when scientists use a 10,000-degree plasma jet to turn boron and nitrogen gas into plasma consisting of free electrons and atomic nuclei, or ions, embedded in a background gas. This shows how the process unfolds:

    • The jet evaporates the boron while the molecular nitrogen largely stays intact;

    • The boron condenses into droplets as the plasma cools;

    • The droplets form small clusters as the temperature falls to a few thousand degrees;

    • The critical next step is the reaction of nitrogen with small clusters of boron molecules to form boron-nitrogen chains;

    • The chains grow longer by colliding with one another and fold into precursors of boron nitride nanotubes.

    “During the high-temperature synthesis the density of small boron clusters is low,” Barsukov said. “This is the main impediment to large-scale production.”

    The findings have opened a new chapter in BNNT nanomaterial synthesis. “After two years of work we have found the pathway,” Kaganovich said. “As boron condenses it forms big clusters that nitrogen doesn’t react with. But the process starts with small clusters that nitrogen reacts with and there is still a percentage of small clusters as the droplets grow larger,” he said.

    “The beauty of this work,” he added, “is that since we had experts in plasma and fluid mechanics and quantum chemistry we could go through all these processes together in an interdisciplinary group. Now we need to compare possible BNNT output from our model with experiments. That will be the next stage of modeling.”

    Support for this research comes from the DOE Office of Science.

    See the full article here .


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    PPPL campus

    Princeton Plasma Physics Laboratory (US) is a U.S. Department of Energy national laboratory managed by Princeton University. PPPL, on Princeton University’s Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas — ultra-hot, charged gases — and to developing practical solutions for the creation of fusion energy. Results of PPPL research have ranged from a portable nuclear materials detector for anti-terrorist use to universally employed computer codes for analyzing and predicting the outcome of fusion experiments. The Laboratory is managed by the University for the U.S. Department of Energy’s Office of Science, which is the largest single supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit https://energy.gov/science.

    Princeton University

    Princeton University

    About Princeton: Overview

    Princeton University is a private Ivy League research university in Princeton, New Jersey(US). Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the nine colonial colleges chartered before the American Revolution. The institution moved to Newark in 1747, then to the current site nine years later. It was renamed Princeton University in 1896.

    Princeton provides undergraduate and graduate instruction in the humanities, social sciences, natural sciences, and engineering. It offers professional degrees through the Princeton School of Public and International Affairs, the School of Engineering and Applied Science, the School of Architecture and the Bendheim Center for Finance. The university also manages the DOE’s Princeton Plasma Physics Laboratory. Princeton has the largest endowment per student in the United States.

    As of October 2020, 69 Nobel laureates, 15 Fields Medalists and 14 Turing Award laureates have been affiliated with Princeton University as alumni, faculty members or researchers. In addition, Princeton has been associated with 21 National Medal of Science winners, 5 Abel Prize winners, 5 National Humanities Medal recipients, 215 Rhodes Scholars, 139 Gates Cambridge Scholars and 137 Marshall Scholars. Two U.S. Presidents, twelve U.S. Supreme Court Justices (three of whom currently serve on the court) and numerous living billionaires and foreign heads of state are all counted among Princeton’s alumni body. Princeton has also graduated many prominent members of the U.S. Congress and the U.S. Cabinet, including eight Secretaries of State, three Secretaries of Defense and the current Chairman of the Joint Chiefs of Staff.

    Princeton University, founded as the College of New Jersey, was considered the successor of the “Log College” founded by the Reverend William Tennent at Neshaminy, PA in about 1726. New Light Presbyterians founded the College of New Jersey in 1746 in Elizabeth, New Jersey. Its purpose was to train ministers. The college was the educational and religious capital of Scottish Presbyterian America. Unlike Harvard University(US), which was originally “intensely English” with graduates taking the side of the crown during the American Revolution, Princeton was founded to meet the religious needs of the period and many of its graduates took the American side in the war. In 1754, trustees of the College of New Jersey suggested that, in recognition of Governor Jonathan Belcher’s interest, Princeton should be named as Belcher College. Belcher replied: “What a name that would be!” In 1756, the college moved its campus to Princeton, New Jersey. Its home in Princeton was Nassau Hall, named for the royal House of Orange-Nassau of William III of England.

    Following the untimely deaths of Princeton’s first five presidents, John Witherspoon became president in 1768 and remained in that post until his death in 1794. During his presidency, Witherspoon shifted the college’s focus from training ministers to preparing a new generation for secular leadership in the new American nation. To this end, he tightened academic standards and solicited investment in the college. Witherspoon’s presidency constituted a long period of stability for the college, interrupted by the American Revolution and particularly the Battle of Princeton, during which British soldiers briefly occupied Nassau Hall; American forces, led by George Washington, fired cannon on the building to rout them from it.

    In 1812, the eighth president of the College of New Jersey, Ashbel Green (1812–23), helped establish the Princeton Theological Seminary next door. The plan to extend the theological curriculum met with “enthusiastic approval on the part of the authorities at the College of New Jersey.” Today, Princeton University and Princeton Theological Seminary maintain separate institutions with ties that include services such as cross-registration and mutual library access.

    Before the construction of Stanhope Hall in 1803, Nassau Hall was the college’s sole building. The cornerstone of the building was laid on September 17, 1754. During the summer of 1783, the Continental Congress met in Nassau Hall, making Princeton the country’s capital for four months. Over the centuries and through two redesigns following major fires (1802 and 1855), Nassau Hall’s role shifted from an all-purpose building, comprising office, dormitory, library, and classroom space; to classroom space exclusively; to its present role as the administrative center of the University. The class of 1879 donated twin lion sculptures that flanked the entrance until 1911, when that same class replaced them with tigers. Nassau Hall’s bell rang after the hall’s construction; however, the fire of 1802 melted it. The bell was then recast and melted again in the fire of 1855.

    James McCosh became the college’s president in 1868 and lifted the institution out of a low period that had been brought about by the American Civil War. During his two decades of service, he overhauled the curriculum, oversaw an expansion of inquiry into the sciences, and supervised the addition of a number of buildings in the High Victorian Gothic style to the campus. McCosh Hall is named in his honor.

    In 1879, the first thesis for a Doctor of Philosophy (Ph.D.) was submitted by James F. Williamson, Class of 1877.

    In 1896, the college officially changed its name from the College of New Jersey to Princeton University to honor the town in which it resides. During this year, the college also underwent large expansion and officially became a university. In 1900, the Graduate School was established.

    In 1902, Woodrow Wilson, graduate of the Class of 1879, was elected the 13th president of the university. Under Wilson, Princeton introduced the preceptorial system in 1905, a then-unique concept in the United States that augmented the standard lecture method of teaching with a more personal form in which small groups of students, or precepts, could interact with a single instructor, or preceptor, in their field of interest.

    In 1906, the reservoir Carnegie Lake was created by Andrew Carnegie. A collection of historical photographs of the building of the lake is housed at the Seeley G. Mudd Manuscript Library on Princeton’s campus. On October 2, 1913, the Princeton University Graduate College was dedicated. In 1919 the School of Architecture was established. In 1933, Albert Einstein became a lifetime member of the Institute for Advanced Study with an office on the Princeton campus. While always independent of the university, the Institute for Advanced Study occupied offices in Jones Hall for 6 years, from its opening in 1933, until its own campus was finished and opened in 1939.

    Coeducation

    In 1969, Princeton University first admitted women as undergraduates. In 1887, the university actually maintained and staffed a sister college, Evelyn College for Women, in the town of Princeton on Evelyn and Nassau streets. It was closed after roughly a decade of operation. After abortive discussions with Sarah Lawrence College to relocate the women’s college to Princeton and merge it with the University in 1967, the administration decided to admit women and turned to the issue of transforming the school’s operations and facilities into a female-friendly campus. The administration had barely finished these plans in April 1969 when the admissions office began mailing out its acceptance letters. Its five-year coeducation plan provided $7.8 million for the development of new facilities that would eventually house and educate 650 women students at Princeton by 1974. Ultimately, 148 women, consisting of 100 freshmen and transfer students of other years, entered Princeton on September 6, 1969 amidst much media attention. Princeton enrolled its first female graduate student, Sabra Follett Meservey, as a PhD candidate in Turkish history in 1961. A handful of undergraduate women had studied at Princeton from 1963 on, spending their junior year there to study “critical languages” in which Princeton’s offerings surpassed those of their home institutions. They were considered regular students for their year on campus, but were not candidates for a Princeton degree.

    As a result of a 1979 lawsuit by Sally Frank, Princeton’s eating clubs were required to go coeducational in 1991, after Tiger Inn’s appeal to the U.S. Supreme Court was denied. In 1987, the university changed the gendered lyrics of “Old Nassau” to reflect the school’s co-educational student body. From 2009 to 2011, Princeton professor Nannerl O. Keohane chaired a committee on undergraduate women’s leadership at the university, appointed by President Shirley M. Tilghman.

    The main campus sits on about 500 acres (2.0 km^2) in Princeton. In 2011, the main campus was named by Travel+Leisure as one of the most beautiful in the United States. The James Forrestal Campus is split between nearby Plainsboro and South Brunswick. The University also owns some property in West Windsor Township. The campuses are situated about one hour from both New York City and Philadelphia.

    The first building on campus was Nassau Hall, completed in 1756 and situated on the northern edge of campus facing Nassau Street. The campus expanded steadily around Nassau Hall during the early and middle 19th century. The McCosh presidency (1868–88) saw the construction of a number of buildings in the High Victorian Gothic and Romanesque Revival styles; many of them are now gone, leaving the remaining few to appear out of place. At the end of the 19th century much of Princeton’s architecture was designed by the Cope and Stewardson firm (same architects who designed a large part of Washington University in St Louis (US) and University of Pennsylvania(US)) resulting in the Collegiate Gothic style for which it is known today. Implemented initially by William Appleton Potter and later enforced by the University’s supervising architect, Ralph Adams Cram, the Collegiate Gothic style remained the standard for all new building on the Princeton campus through 1960. A flurry of construction in the 1960s produced a number of new buildings on the south side of the main campus, many of which have been poorly received. Several prominent architects have contributed some more recent additions, including Frank Gehry (Lewis Library), I. M. Pei (Spelman Halls), Demetri Porphyrios (Whitman College, a Collegiate Gothic project), Robert Venturi and Denise Scott Brown (Frist Campus Center, among several others), and Rafael Viñoly (Carl Icahn Laboratory).

    A group of 20th-century sculptures scattered throughout the campus forms the Putnam Collection of Sculpture. It includes works by Alexander Calder (Five Disks: One Empty), Jacob Epstein (Albert Einstein), Henry Moore (Oval with Points), Isamu Noguchi (White Sun), and Pablo Picasso (Head of a Woman). Richard Serra’s The Hedgehog and The Fox is located between Peyton and Fine halls next to Princeton Stadium and the Lewis Library.

    At the southern edge of the campus is Carnegie Lake, an artificial lake named for Andrew Carnegie. Carnegie financed the lake’s construction in 1906 at the behest of a friend who was a Princeton alumnus. Carnegie hoped the opportunity to take up rowing would inspire Princeton students to forsake football, which he considered “not gentlemanly.” The Shea Rowing Center on the lake’s shore continues to serve as the headquarters for Princeton rowing.

    Cannon Green

    Buried in the ground at the center of the lawn south of Nassau Hall is the “Big Cannon,” which was left in Princeton by British troops as they fled following the Battle of Princeton. It remained in Princeton until the War of 1812, when it was taken to New Brunswick. In 1836 the cannon was returned to Princeton and placed at the eastern end of town. It was removed to the campus under cover of night by Princeton students in 1838 and buried in its current location in 1840.

    A second “Little Cannon” is buried in the lawn in front of nearby Whig Hall. This cannon, which may also have been captured in the Battle of Princeton, was stolen by students of Rutgers University in 1875. The theft ignited the Rutgers-Princeton Cannon War. A compromise between the presidents of Princeton and Rutgers ended the war and forced the return of the Little Cannon to Princeton. The protruding cannons are occasionally painted scarlet by Rutgers students who continue the traditional dispute.

    In years when the Princeton football team beats the teams of both Harvard University and Yale University in the same season, Princeton celebrates with a bonfire on Cannon Green. This occurred in 2012, ending a five-year drought. The next bonfire happened on November 24, 2013, and was broadcast live over the Internet.

    Landscape

    Princeton’s grounds were designed by Beatrix Farrand between 1912 and 1943. Her contributions were most recently recognized with the naming of a courtyard for her. Subsequent changes to the landscape were introduced by Quennell Rothschild & Partners in 2000. In 2005, Michael Van Valkenburgh was hired as the new consulting landscape architect for the campus. Lynden B. Miller was invited to work with him as Princeton’s consulting gardening architect, focusing on the 17 gardens that are distributed throughout the campus.

    Buildings

    Nassau Hall

    Nassau Hall is the oldest building on campus. Begun in 1754 and completed in 1756, it was the first seat of the New Jersey Legislature in 1776, was involved in the battle of Princeton in 1777, and was the seat of the Congress of the Confederation (and thus capitol of the United States) from June 30, 1783, to November 4, 1783. It now houses the office of the university president and other administrative offices, and remains the symbolic center of the campus. The front entrance is flanked by two bronze tigers, a gift of the Princeton Class of 1879. Commencement is held on the front lawn of Nassau Hall in good weather. In 1966, Nassau Hall was added to the National Register of Historic Places.

    Residential colleges

    Princeton has six undergraduate residential colleges, each housing approximately 500 freshmen, sophomores, some juniors and seniors, and a handful of junior and senior resident advisers. Each college consists of a set of dormitories, a dining hall, a variety of other amenities—such as study spaces, libraries, performance spaces, and darkrooms—and a collection of administrators and associated faculty. Two colleges, First College and Forbes College (formerly Woodrow Wilson College and Princeton Inn College, respectively), date to the 1970s; three others, Rockefeller, Mathey, and Butler Colleges, were created in 1983 following the Committee on Undergraduate Residential Life (CURL) report, which suggested the institution of residential colleges as a solution to an allegedly fragmented campus social life. The construction of Whitman College, the university’s sixth residential college, was completed in 2007.

    Rockefeller and Mathey are located in the northwest corner of the campus; Princeton brochures often feature their Collegiate Gothic architecture. Like most of Princeton’s Gothic buildings, they predate the residential college system and were fashioned into colleges from individual dormitories.

    First and Butler, located south of the center of the campus, were built in the 1960s. First served as an early experiment in the establishment of the residential college system. Butler, like Rockefeller and Mathey, consisted of a collection of ordinary dorms (called the “New New Quad”) before the addition of a dining hall made it a residential college. Widely disliked for their edgy modernist design, including “waffle ceilings,” the dormitories on the Butler Quad were demolished in 2007. Butler is now reopened as a four-year residential college, housing both under- and upperclassmen.

    Forbes is located on the site of the historic Princeton Inn, a gracious hotel overlooking the Princeton golf course. The Princeton Inn, originally constructed in 1924, played regular host to important symposia and gatherings of renowned scholars from both the university and the nearby Institute for Advanced Study for many years. Forbes currently houses nearly 500 undergraduates in its residential halls.

    In 2003, Princeton broke ground for a sixth college named Whitman College after its principal sponsor, Meg Whitman, who graduated from Princeton in 1977. The new dormitories were constructed in the Collegiate Gothic architectural style and were designed by architect Demetri Porphyrios. Construction finished in 2007, and Whitman College was inaugurated as Princeton’s sixth residential college that same year.

    The precursor of the present college system in America was originally proposed by university president Woodrow Wilson in the early 20th century. For over 800 years, however, the collegiate system had already existed in Britain at Cambridge and Oxford Universities. Wilson’s model was much closer to Yale University (US)’s present system, which features four-year colleges. Lacking the support of the trustees, the plan languished until 1968. That year, Wilson College was established to cap a series of alternatives to the eating clubs. Fierce debates raged before the present residential college system emerged. The plan was first attempted at Yale, but the administration was initially uninterested; an exasperated alumnus, Edward Harkness, finally paid to have the college system implemented at Harvard in the 1920s, leading to the oft-quoted aphorism that the college system is a Princeton idea that was executed at Harvard with funding from Yale.

    Princeton has one graduate residential college, known simply as the Graduate College, located beyond Forbes College at the outskirts of campus. The far-flung location of the GC was the spoil of a squabble between Woodrow Wilson and then-Graduate School Dean Andrew Fleming West. Wilson preferred a central location for the college; West wanted the graduate students as far as possible from the campus. Ultimately, West prevailed. The Graduate College is composed of a large Collegiate Gothic section crowned by Cleveland Tower, a local landmark that also houses a world-class carillon. The attached New Graduate College provides a modern contrast in architectural style.

    McCarter Theatre

    The Tony-award-winning McCarter Theatre was built by the Princeton Triangle Club, a student performance group, using club profits and a gift from Princeton University alumnus Thomas McCarter. Today, the Triangle Club performs its annual freshmen revue, fall show, and Reunions performances in McCarter. McCarter is also recognized as one of the leading regional theaters in the United States.

    Art Museum

    The Princeton University Art Museum was established in 1882 to give students direct, intimate, and sustained access to original works of art that complement and enrich instruction and research at the university. This continues to be a primary function, along with serving as a community resource and a destination for national and international visitors.

    Numbering over 92,000 objects, the collections range from ancient to contemporary art and concentrate geographically on the Mediterranean regions, Western Europe, China, the United States, and Latin America. There is a collection of Greek and Roman antiquities, including ceramics, marbles, bronzes, and Roman mosaics from faculty excavations in Antioch. Medieval Europe is represented by sculpture, metalwork, and stained glass. The collection of Western European paintings includes examples from the early Renaissance through the 19th century, with masterpieces by Monet, Cézanne, and Van Gogh, and features a growing collection of 20th-century and contemporary art, including iconic paintings such as Andy Warhol’s Blue Marilyn.

    One of the best features of the museums is its collection of Chinese art, with important holdings in bronzes, tomb figurines, painting, and calligraphy. Its collection of pre-Columbian art includes examples of Mayan art, and is commonly considered to be the most important collection of pre-Columbian art outside of Latin America. The museum has collections of old master prints and drawings and a comprehensive collection of over 27,000 original photographs. African art and Northwest Coast Indian art are also represented. The Museum also oversees the outdoor Putnam Collection of Sculpture.

    University Chapel

    The Princeton University Chapel is located on the north side of campus, near Nassau Street. It was built between 1924 and 1928, at a cost of $2.3 million [approximately $34.2 million in 2020 dollars]. Ralph Adams Cram, the University’s supervising architect, designed the chapel, which he viewed as the crown jewel for the Collegiate Gothic motif he had championed for the campus. At the time of its construction, it was the second largest university chapel in the world, after King’s College Chapel, Cambridge. It underwent a two-year, $10 million restoration campaign between 2000 and 2002.

    Measured on the exterior, the chapel is 277 feet (84 m) long, 76 feet (23 m) wide at its transepts, and 121 feet (37 m) high. The exterior is Pennsylvania sandstone, with Indiana limestone used for the trim. The interior is mostly limestone and Aquia Creek sandstone. The design evokes an English church of the Middle Ages. The extensive iconography, in stained glass, stonework, and wood carvings, has the common theme of connecting religion and scholarship.

    The Chapel seats almost 2,000. It hosts weekly ecumenical Christian services, daily Roman Catholic mass, and several annual special events.

    Murray-Dodge Hall

    Murray-Dodge Hall houses the Office of Religious Life (ORL), the Murray Dodge Theater, the Murray-Dodge Café, the Muslim Prayer Room and the Interfaith Prayer Room. The ORL houses the office of the Dean of Religious Life, Alison Boden, and a number of university chaplains, including the country’s first Hindu chaplain, Vineet Chander; and one of the country’s first Muslim chaplains, Sohaib Sultan.

    Sustainability

    Published in 2008, Princeton’s Sustainability Plan highlights three priority areas for the University’s Office of Sustainability: reduction of greenhouse gas emissions; conservation of resources; and research, education, and civic engagement. Princeton has committed to reducing its carbon dioxide emissions to 1990 levels by 2020: Energy without the purchase of offsets. The University published its first Sustainability Progress Report in November 2009. The University has adopted a green purchasing policy and recycling program that focuses on paper products, construction materials, lightbulbs, furniture, and electronics. Its dining halls have set a goal to purchase 75% sustainable food products by 2015. The student organization “Greening Princeton” seeks to encourage the University administration to adopt environmentally friendly policies on campus.

    Organization

    The Trustees of Princeton University, a 40-member board, is responsible for the overall direction of the University. It approves the operating and capital budgets, supervises the investment of the University’s endowment and oversees campus real estate and long-range physical planning. The trustees also exercise prior review and approval concerning changes in major policies, such as those in instructional programs and admission, as well as tuition and fees and the hiring of faculty members.

    With an endowment of $26.1 billion, Princeton University is among the wealthiest universities in the world. Ranked in 2010 as the third largest endowment in the United States, the university had the greatest per-student endowment in the world (over $2 million for undergraduates) in 2011. Such a significant endowment is sustained through the continued donations of its alumni and is maintained by investment advisers. Some of Princeton’s wealth is invested in its art museum, which features works by Claude Monet, Vincent van Gogh, Jackson Pollock, and Andy Warhol among other prominent artists.

    Academics

    Undergraduates fulfill general education requirements, choose among a wide variety of elective courses, and pursue departmental concentrations and interdisciplinary certificate programs. Required independent work is a hallmark of undergraduate education at Princeton. Students graduate with either the Bachelor of Arts (A.B.) or the Bachelor of Science in Engineering (B.S.E.).

    The graduate school offers advanced degrees spanning the humanities, social sciences, natural sciences, and engineering. Doctoral education is available in most disciplines. It emphasizes original and independent scholarship whereas master’s degree programs in architecture, engineering, finance, and public affairs and public policy prepare candidates for careers in public life and professional practice.

    The university has ties with the Institute for Advanced Study, Princeton Theological Seminary and the Westminster Choir College of Rider University(US).

    Undergraduate

    Undergraduate courses in the humanities are traditionally either seminars or lectures held 2 or 3 times a week with an additional discussion seminar that is called a “precept.” To graduate, all A.B. candidates must complete a senior thesis and, in most departments, one or two extensive pieces of independent research that are known as “junior papers.” Juniors in some departments, including architecture and the creative arts, complete independent projects that differ from written research papers. A.B. candidates must also fulfill a three or four semester foreign language requirement and distribution requirements (which include, for example, classes in ethics, literature and the arts, and historical analysis) with a total of 31 classes. B.S.E. candidates follow a parallel track with an emphasis on a rigorous science and math curriculum, a computer science requirement, and at least two semesters of independent research including an optional senior thesis. All B.S.E. students must complete at least 36 classes. A.B. candidates typically have more freedom in course selection than B.S.E. candidates because of the fewer number of required classes. Nonetheless, in the spirit of a liberal arts education, both enjoy a comparatively high degree of latitude in creating a self-structured curriculum.

    Undergraduates agree to adhere to an academic integrity policy called the Honor Code, established in 1893. Under the Honor Code, faculty do not proctor examinations; instead, the students proctor one another and must report any suspected violation to an Honor Committee made up of undergraduates. The Committee investigates reported violations and holds a hearing if it is warranted. An acquittal at such a hearing results in the destruction of all records of the hearing; a conviction results in the student’s suspension or expulsion. The signed pledge required by the Honor Code is so integral to students’ academic experience that the Princeton Triangle Club performs a song about it each fall. Out-of-class exercises fall under the jurisdiction of the Faculty-Student Committee on Discipline. Undergraduates are expected to sign a pledge on their written work affirming that they have not plagiarized the work.

    Graduate

    The Graduate School has about 2,600 students in 42 academic departments and programs in social sciences; engineering; natural sciences; and humanities. These departments include the Department of Psychology; Department of History; and Department of Economics.

    In 2017–2018, it received nearly 11,000 applications for admission and accepted around 1,000 applicants. The University also awarded 319 Ph.D. degrees and 170 final master’s degrees. Princeton has no medical school, law school, business school, or school of education. (A short-lived Princeton Law School folded in 1852.) It offers professional graduate degrees in architecture; engineering; finance and public policy- the last through the Princeton School of Public and International Affairs founded in 1930 as the School of Public and International Affairs and renamed in 1948 after university president (and U.S. president) Woodrow Wilson, and most recently renamed in 2020.

    Libraries

    The Princeton University Library system houses over eleven million holdings including seven million bound volumes. The main university library, Firestone Library, which houses almost four million volumes, is one of the largest university libraries in the world. Additionally, it is among the largest “open stack” libraries in existence. Its collections include the autographed manuscript of F. Scott Fitzgerald’s The Great Gatsby and George F. Kennan’s Long Telegram. In addition to Firestone library, specialized libraries exist for architecture, art and archaeology, East Asian studies, engineering, music, public and international affairs, public policy and university archives, and the sciences. In an effort to expand access, these libraries also subscribe to thousands of electronic resources.

    Institutes

    High Meadows Environmental Institute

    The High Meadows Environmental Institute is an “interdisciplinary center of environmental research, education, and outreach” at the university. The institute was started in 1994. About 90 faculty members at Princeton University are affiliated with it.

    The High Meadows Environmental Institute has the following research centers:

    Carbon Mitigation Initiative (CMI): This is a 15-year-long partnership between PEI and British Petroleum with the goal of finding solutions to problems related to climate change. The Stabilization Wedge Game has been created as part of this initiative.
    Center for BioComplexity (CBC)
    Cooperative Institute for Climate Science (CICS): This is a collaboration with the National Oceanographic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory.
    Energy Systems Analysis Group
    Grand Challenges

     
  • richardmitnick 12:35 pm on May 29, 2021 Permalink | Reply
    Tags: "Energy on Demand-Learning from Nature’s Catalysts", "Janus intermediate", , “Big questions in biocatalysis”-specifically how to control matter and energy., , , , , Enzymes: nature’s catalysts, How natural catalysts churn out specific reactions-over and over-in the blink of an eye., Nitrogenase: an enzyme found in soil-dwelling microorganisms that has a unique ability to break apart nitrogen’s triple bond-one of the strongest bonds in nature., , Quantum Chemistry,   

    From DOE’s Pacific Northwest National Laboratory (US) : “Energy on Demand-Learning from Nature’s Catalysts” 

    From DOE’s Pacific Northwest National Laboratory (US)

    April 26, 2021 [Just now in social media.]
    Lynne Roeder, PNNL

    New Energy Sciences Center, quantum chemistry to accelerate enzyme research.

    1
    Nitrogenase. Credit: PNNL.

    About 15 years ago, Simone Raugei started simulating chemistry experiments at the molecular level.

    Today, as part of a top-notch research team aided by advanced computing, Raugei and his colleagues stand primed to crack an important hidden code: nature’s intricate method for releasing energy on demand.

    “We want to know how to funnel energy precisely at the right time, in the right spot, to perform the chemical reaction we want—just like enzymes do in nature,” said Raugei, a computational scientist who leads the physical biosciences research at Pacific Northwest National Laboratory (PNNL). “Advances in computing have helped us make tremendous progress in the past five or six years. We now have a critical mass of capabilities and knowledge.”

    The research is part of PNNL’s focus on reinventing chemical conversions, which supports the goals of the U.S. Department of Energy Office of Science, Basic Energy Sciences (BES) program. One of the programs’ many goals is to understand, at an atomic level, how natural catalysts churn out specific reactions-over and over-in the blink of an eye.

    The ability to mimic these natural reactions could profoundly improve the design of new synthetic catalysts for producing cleaner and more efficient energy, industrial processes, and materials.

    Raugei described the BES Physical Biosciences program as the visionary effort that brought together individual research groups and experimentalists to collaborate on “big questions in biocatalysis”—specifically, how to control matter and energy.

    The questions don’t get much bigger than that.

    Enzymes: nature’s catalysts

    At PNNL, Raugei teams closely with fellow computational scientists Bojana Ginovska and Marcel Baer to examine the inner workings of enzymes. Found within every living cell, these miniscule multi-taskers direct all sorts of reactions for different functions.

    Through feedback loops between theory, computer simulations, and experimentation among PNNL and university collaborators, the scientists have made steady progress in uncovering the molecular machinations of several types of enzymes. They are particularly interested in nitrogenase, an enzyme found in soil-dwelling microorganisms, that has a unique ability to break apart nitrogen’s triple bond—one of the strongest bonds in nature. That molecular fracture, which occurs in the buried active core of nitrogenase, produces ammonia.

    In the world of commercial chemistry, ammonia is used to make many valuable products, such as fertilizer. But producing ammonia at an industrial scale takes a lot of energy. Much of that energy is spent trying to break nitrogen’s sturdy triple bonds. Figuring out how nature does it so efficiently is key to designing new synthetic catalysts that improve the production process for ammonia and other commercial products.


    Quantum Chemistry. Credit: PNNL.

    Nitrogenase: cracking the code

    About two years ago, the team of PNNL and university scientists isolated the elusive molecular structure inside nitrogenase—called the Janus intermediate—that represents the ‘point of no return’ in the production of ammonia. The researchers found that two negatively charged hydrogens, called hydrides, form bridges with two iron ions. Those bridges allow four extra electrons to park inside the core cluster of atoms.

    The team’s latest research confirmed the shuffling of electrons within the protein environment, packing in enough energy to break apart the nitrogen bonds and form ammonia. Powerful spectroscopy techniques were used to probe the magnetic interactions between electrons in the enzyme’s metallic core. Those interactions were then correlated with quantum simulations of the enzyme’s transformation to yield the molecular structure of the Janus intermediate.

    “The energetics of the electron delivery are amazing,” said Raugei. “When you think of adding electrons into a tiny cluster of atoms, one electron is difficult, two is harder, three is really hard, and to add the fourth is generally considered impossible. But we found that’s how it happens.”

    Lance Seefeldt, a professor at Utah State University (US) who holds a joint appointment at PNNL, leads the experimental work for the team’s nitrogenase research. Another key collaborator, and the “mastermind behind the spectroscopy measurements” according to Raugei, is Brian Hoffman from Northwestern University (US). The team’s most recent findings about nitrogenase were published in the Journal of the American Chemical Society in December 2020.

    Quantum chemistry collaborations

    Ginovska helps direct the day-to-day activities of the group’s postdoctoral researchers working on the project. She credits Raugei with establishing and maintaining connections among the scientific community to spur progress on enzyme research.

    “As a theoretical hub, we collaborate with universities and other national laboratories for the experimental aspects of the research,” said Ginovska. “We started with nitrogenase and it grew from there. We are now working on several enzymatic systems. All of that work is feeding into the same knowledge base.”

    Karl Mueller, chief science and technology officer for PNNL’s Physical and Computational Sciences Directorate, said nitrogenase is a prime example of the challenging problems that can be tackled at a national laboratory through collaboration between experimental and computational scientists, including university researchers. As the scientists prepare to move into PNNL’s new Energy Sciences Center in the fall of 2021, Raugei is confident the enhanced capabilities and collaborative environment will help the team soon crack the remaining code of how nitrogenase forms ammonia.

    “We know that it has to do with adding hydrogen atoms, but how? There are a multitude of possible pathways and that’s what we’re looking into now,” said Raugei. “This is definitely an application where breakthroughs in quantum computing will accelerate our research and elevate our understanding of complex systems.”

    As the pace of scientific progress speeds forward, nitrogenase is just one example of how the promise of quantum chemistry, quantum computing, and PNNL’s Energy Sciences Center could help answer the next big question in catalysis.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    DOE’s Pacific Northwest National Laboratory (PNNL) (US) is one of the United States Department of Energy National Laboratories, managed by the Department of Energy’s Office of Science. The main campus of the laboratory is in Richland, Washington.

    PNNL scientists conduct basic and applied research and development to strengthen U.S. scientific foundations for fundamental research and innovation; prevent and counter acts of terrorism through applied research in information analysis, cyber security, and the nonproliferation of weapons of mass destruction; increase the U.S. energy capacity and reduce dependence on imported oil; and reduce the effects of human activity on the environment. PNNL has been operated by Battelle Memorial Institute since 1965.

     
  • richardmitnick 10:36 pm on December 21, 2020 Permalink | Reply
    Tags: "Artificial Intelligence Solves Schrödinger’s Equation", , “Pauli’s exclusion principle”, “Quantum Monte Carlo”, Central to both quantum chemistry and the Schrödinger equation is the wave function., Freie Universität Berlin (DE), One peculiar feature of electronic wave functions is their antisymmetry., Quantum Chemistry   

    From Freie Universität Berlin (DE): “Artificial Intelligence Solves Schrödinger’s Equation” 

    From Freie Universität Berlin (DE)

    Dec 18, 2020
    Prof. Dr. Frank Noé
    Department of Mathematics and Computer Science
    Freie Universität Berlin
    frank.noe@fu-berlin.de
    Tel.: +49 30 838 75354

    1
    Credit: CC0 Public Domain.

    Scientists at Freie Universität Berlin develop a deep learning method to solve a fundamental problem in quantum chemistry.

    A team of scientists at Freie Universität Berlin has developed an artificial intelligence (AI) method for calculating the ground state of the Schrödinger equation in quantum chemistry. The goal of quantum chemistry is to predict chemical and physical properties of molecules based solely on the arrangement of their atoms in space, avoiding the need for resource-intensive and time-consuming laboratory experiments. In principle, this can be achieved by solving the Schrödinger equation, but in practice this is extremely difficult. Up to now, it has been impossible to find an exact solution for arbitrary molecules that can be efficiently computed. But the team at Freie Universität has developed a deep learning method that can achieve an unprecedented combination of accuracy and computational efficiency. AI has transformed many technological and scientific areas, from computer vision to materials science. “We believe that our approach may significantly impact the future of quantum chemistry,” says Professor Frank Noé, who led the team effort. The results were published in the reputed journal Nature Chemistry.

    Central to both quantum chemistry and the Schrödinger equation is the wave function – a mathematical object that completely specifies the behavior of the electrons in a molecule. The wave function is a high-dimensional entity, and it is therefore extremely difficult to capture all the nuances that encode how the individual electrons affect each other. Many methods of quantum chemistry in fact give up on expressing the wave function altogether, instead attempting only to determine the energy of a given molecule. This however requires approximations to be made, limiting the prediction quality of such methods.

    Other methods represent the wave function with the use of an immense number of simple mathematical building blocks, but such methods are so complex that they are impossible to put into practice for more than a mere handful of atoms. “Escaping the usual trade-off between accuracy and computational cost is the highest achievement in quantum chemistry,” explains Dr. Jan Hermann of Freie Universität Berlin, who designed the key features of the method in the study. “As yet, the most popular such outlier is the extremely cost-effective density functional theory. We believe that deep “Quantum Monte Carlo,” the approach we are proposing, could be equally, if not more successful. It offers unprecedented accuracy at a still acceptable computational cost.”

    The deep neural network designed by Professor Noé’s team is a new way of representing the wave functions of electrons. “Instead of the standard approach of composing the wave function from relatively simple mathematical components, we designed an artificial neural network capable of learning the complex patterns of how electrons are located around the nuclei,” Noé explains. “One peculiar feature of electronic wave functions is their antisymmetry. When two electrons are exchanged, the wave function must change its sign. We had to build this property into the neural network architecture for the approach to work,” adds Hermann. This feature, known as “Pauli’s exclusion principle,” is why the authors called their method “PauliNet.”

    Besides the Pauli exclusion principle, electronic wave functions also have other fundamental physical properties, and much of the innovative success of PauliNet is that it integrates these properties into the deep neural network, rather than letting deep learning figure them out by just observing the data. “Building the fundamental physics into the AI is essential for its ability to make meaningful predictions in the field,” says Noé. “This is really where scientists can make a substantial contribution to AI, and exactly what my group is focused on.”

    There are still many challenges to overcome before Hermann and Noé’s method is ready for industrial application. “This is still fundamental research,” the authors agree, “but it is a fresh approach to an age-old problem in the molecular and material sciences, and we are excited about the possibilities it opens up.”

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Freie Universität Berlin is a leading research institution. It is one of the 13 German universities being funded through the German government’s Excellence Strategy and is part of the only University Consortium of Excellence, the Berlin University Alliance. The four Berlin partners – Freie Universität Berlin, Humboldt-Universität zu Berlin, Technische Universität Berlin, and Charité – Universitätsmedizin Berlin – submitted a joint proposal in the Excellence Strategy entitled Crossing Boundaries toward an Integrated Research Environment. The four institutions’ long-term goal is nothing less than to turn Berlin into an integrated research environment and one of Europe’s leading research hubs.

    Through the Dahlem Research School, Freie Universität Berlin promotes the training and development of junior scholars and scientists. The university maintains more than 100 international partnerships with universities worldwide. About 17 percent of its students come from abroad. Freie Universität Berlin has 16 academic departments and central institutes offering over 150 degree programs across a wide range of subjects.

     
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