SCIENTIFIC SOLUTIONS Simon M Pratt & Robert A Stembridge An analysis of citations in scientific and patent literature to historical research from the first

SCIENTIFIC SOLUTIONS

Simon M Pratt & Robert A Stembridge

An analysis of citations in scientific and patent literature to historical research from the first half of the 20th century and the relationship to

the accessibility of these works through electronic archives

Copyright 2006 ThomsonSlide 2


• The Web of Science and previous versions of the Science Citation Index (SCI, SciSearch) have long been considered the standard for bibliometrics and the analysis of citations for research evaluation

• The introduction of a new archive, called the Century of Science, has extended the retrospective coverage of the Web of Science for the period 1900 to 1944.

• This has made it possible to comprehensively analyze the citations to historic works of the early part of the 20th century, a so called golden era for scientific discovery, especially in the field of theoretical chemistry and physics.

• There are several very highly cited works in this period, and many of these are being more heavily cited today than at any time in their history.



• The most obvious example of this phenomenom is the works of Albert Einstein.

• As can be seen by this diagram showing citations to Einstein’s 1905 paper on the Special Theory of relativity, the number of citations per year has increased dramatically in the last 10 years or so.

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• This trend is a direct contradiction to the expected trend for the journal that this article was published in, Annalen Der Physik. A comparison with the citation trend for all articles published in the same journal between 1900 and 1904 shows this clearly.

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• There are several logical explanations for this trend such as:– Research in that particular field has not yet reached a satisfying

conclusion, and the research is still valid in the modern era

– The theories discussed in the article are so revolutionary that it takes sometime before they can be understood and utilized by the larger research community

– Historical reasons; in this case 2005 was the 100 year anniversary of the publication of the article and the 50 year anniversary of Einstein's death

– Increased visibility and accessibility to Einstein’s work has led to researchers re-discovering long forgotten works

• We believe that all of these are contributing factors to the increasing rate of citations.



• Not all articles follow the same trend.

• We can see a good example of this when we compare the 5 mostly highly cited articles in the Century of Science

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Fiske CH

Lineweaver, H

Nelson, N

Brunauer, S

Moller, C



• The first 3 articles, all of which have decliningcitation rates, are concernedwith the determination of physical constants

• However the last 2 articlesare more interesting. They show and increase in citations in the last 10 years that far exceeds their historic citation rates. A quick inspection of their titles shows that they would appear to be relevant to current research.

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Fiske CH

Lineweaver, H

Nelson, N

Brunauer, S

Moller, C

Brunauer, S; Emmett, PH; Teller, E Adsorption of gases in multimolecular layers

Moller, C; Plesset, MS

Note on an approximation treatment for many-electron systems



• The Stephen Brunauer, Paul Hugh Emmett and Edward Teller article outlines the BET theory of gas absorption which is commonly used by many researchers today.

• The article also outlines a method to calculate the surface area of solids such as powders or micro particles.

• There are many applications forthis research, such as nano-technology, pollution control and catalysis.

• By limiting the 6,700 citing articles to just those published in 2005-2006 (618 articles), we can further analyze the results to find out how this article is being cited now.

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Citing Institutes

• The citing articles are very international in scope, signifying that this article is very well known throughout the scientific community, as would be expected for an article of this age

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CNR, Italy

DELFT UNIV TECHNOL, Netherlands

KOREA ADV INST SCI & TECHNOL, South Korea

MARIE CURIE SKLODOWSKA UNIV, Poland

NATL ACAD SCI UKRAINE, Ukraine

OAK RIDGE NATL LAB, USA

TOKYO INST TECHNOL, Japan

UFRGS, Brazil

UNIV BOLOGNA, Italy

CSIC, Spain

TIANJIN UNIV, Peoples R China

UNIV EXTREMADURA, Spain

UNIV MONTPELLIER 2, France

KOREA RES INST CHEM TECHNOL, South Korea

CNRS, France



Citing Subject Categories

• Nothing surprising here; these are the fields that you would expect for an article dealing with gas absorption and surface area of micro particles

• Note the absence of History & Philosophy of Science, signifying that this article is not being cited because of its historic significance (different to Einstein)

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NANOSCIENCE & NANOTECHNOLOGY

CHEMISTRY, MULTIDISCIPLINARY

GEOCHEMISTRY & GEOPHYSICS

PHYSICS, APPLIED

CHEMISTRY, APPLIED

ENVIRONMENTAL SCIENCES

ENGINEERING, CHEMICAL

MATERIALS SCIENCE, MULTIDISCIPLINARY

CHEMISTRY, PHYSICAL



Citing Journals

• Again there are no surprises here which further supports the idea that citations to this article are not any kind of anomaly, or that it is being cited for reasons other than the impact of this article on current research

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APPLIED SURFACE SCIENCE

INDUSTRIAL & ENGINEERING CHEMISTRY RES

CARBON

JOURNAL OF HAZARDOUS MATERIALS

APPLIED CATALYSIS A-GENERAL

COLLOIDS AND SURFACES A-PHYSICOCHEM

ENVIRONMENTAL SCIENCE & TECHNOLOGY

JOURNAL OF FOOD ENGINEERING

CHEMISTRY OF MATERIALS

JOURNAL OF MATERIALS CHEMISTRY

GEOCHIMICA ET COSMOCHIMICA ACTA

LANGMUIR

JOURNAL OF PHYSICAL CHEMISTRY B

MICROPOROUS AND MESOPOROUS MATERIALS

JOURNAL OF COLLOID AND INTERFACE SCIENCE



• By looking at 22 of the most recent citing articles, and studying the context of the citations it can be seen that there are 3 general variations on the context of the citation.

– “Historical Reference” - e.g. “The BET model extends the Langmuir model” these are often cited in the introduction

– “Use of Method” - e.g. “Surface areas were estimated according to the BET model”

– “General reference” : referring to an element of the original article and building upon that work

Of the 22 citing articles that were studied:– Historical Reference 14%

– Use of Method 68%

– General Reference 18%



Survey

• We conducted a short survey of researchers who cited the article within the last year.

• Sent 200 e-mails, and received 72 replies (much higher than expected)

• The respondents were very international with replies from all geographic regions including some unexpected places such as Morocco

• Respondents were primarily academics, but several from government and corporate research too



Question 1

• Where did you first hear about the article “Adsorption of gases in multimolecular layers”

a. Through a colleague

b. I have always known about this article / It is so long ago that I forget

c. From a web search

d. From a bibliographic database

e. From a reference in another article or book

f. Other (please specify in your answer)

Of those that said “Other” all of them reported that they had first heard of this article as part of an academic course

Interesting Quote “Actually, I read about it when I was a graduate student, in the 1950s”

Results

– 21%– 22%

– 1%– 1%– 50%– 4%



Question 2

• How did you then locate a copy of the full text of the article?

a. From an electronic full text archive

b. From the print copy of the journal at my library

c. From a colleague

d. Through the internet

e. Other (please specify in your answer)

Of those that said “Other” most had read translations of the article available in local language books

Interesting quote “for this article the full text was not retrieved. It simply is used to report the method used by the software of our surface area analysis instrument.”

Results

– 15%– 51%– 19%– 4%– 10%



Question 3

• Aside from the historical perspective of this article, how relevant is it to your research now?

a. very relevant

b. Somewhat relevant

c. not relevant, only of historical interest

Clearly this historic research published in 1938 is still relevant to research today

Interesting quote “The BET method is still used to analyze adsorption isotherms but is being replaced (somewhat) by DFT methods”

Results

– 54%– 32%– 14%



Analysis of papers citing patents published in 1900

• Later published papers citing patents published in 1900 were identified and analyzed by publication year

• No clear trend is observable

• Patents published in 1900 continue to be cited to the present day

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Citing subject categories

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Materials Science, Ceramics

Materials Science, Multidisciplinary

Biochemistry & Molecular Biology

Imaging Science & Photographic Technology

Multidisciplinary Sciences

Electrochemistry

Engineering, Chemical

Polymer Science

Chemistry, Analytical

Engineering, Electrical & Electronic

Metallurgy & Metallurgical Engineering

Chemistry, Organic

Chemistry, Physical

Chemistry, Applied

Chemistry, Multidisciplinary



Citing journals

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BULLETIN DE LA SOCIETE CHIMIQUE DE FRANCE

JOURNAL OF INDUSTRIAL AND ENGINEERINGCHEMISTRY-US

PHOTOGRAPHIC SCIENCE AND ENGINEERING

USPEKHI KHIMII

BERICHTE DER DEUTSCHEN CHEMISCHENGESELLSCHAFT

JOURNAL OF ORGANIC CHEMISTRY

PROCEEDINGS OF THE IEEE

ZEITSCHRIFT FUR ELEKTROCHEMIE

CHEMICAL REVIEWS

JOURNAL OF THE AMERICAN CERAMIC SOCIETY

INDUSTRIAL AND ENGINEERING CHEMISTRY



Example: 2005 published paper citing a 1900 patent







Patents citing papers published pre-1950; an example



Conclusions

• Some classic historic research is increasingly heavily cited

• Analysis of the citing material suggests that the citations to the work are genuine and are not any kind of anomaly or historical study

• A survey of citing authors shows that – The majority found this article from a cited reference of bibliography of another

work, Web Searching does not seem to have played a major role in the awareness of this article.

– The majority of researchers still access the full text of this article via the print journal, this may reflect a lack of access to the electronic copy

– The majority of researchers still believe that this work is relevant to their research

• A citation analysis of the relationship between patents and articles shows that historic patents are also still being cited, but there is no clear evidence of an increasing citation rate

• Citations from patents to articles, and from articles to patents can reveal valuable information and should not be ignored.

• Retrospective coverage of both journals and patents is valuable to current research



Thank you!

Documents

SCIENTIFIC SOLUTIONS Simon M Pratt & Robert A Stembridge An analysis of citations in scientific and patent literature to historical research from the first