andreas richter room u2090 tel: 218 62103 e-mail: [email protected]

1

Measurement TechniquesTechnical Information

and Some Hints for the Reports

Practical Measurement Techniques, University of Bremen, summer 2014

Andreas Richter

room U2090

tel: 218 62103

e-mail: [email protected]

Christian Mertens

room M 3140

Tel: 218 62147

e-mail [email protected]

General Information I

The Measurement Techniques course consists of

• a series of lectures about selected measurement techniques in environmental science

• a series of lectures related to the lab experiments

• the lab experiments

• an oral exam at the end

- 2 -A. Richter & C. Mertens, Measurement Techniques summer 2014

Preliminary Time Schedule: Lectures


9:15– 10:45 11:15 – 12:45 14:15 – 15:45 16:00 – 17:00

April 23

Introduction / DOAS

(Mertens / Richter)

Absorption Spectroscopy

(Gorshelev)

Measurements of Trace Gases

(Richter)

Safety instructions

(Thomssen)

April 30

Measurement Techniques in Oceanography

(Mertens)

Radioactivity

(Pittauerova)

Satellite Image Analysis

(Melsheimer)

May 7

Cavity Ring Down Spectroscopy

(Horstjann)

Fourier Transform Spectroscopy

(Petri)

Meteorological Measurements

(Richter)

http://www.msc-ep.uni-bremen.de/services/lectures/practicals/meas_tech_doas_ar.ppt

General Information I

• In total 4 lab experiments have to be completed successfully• The labs will take place on Wednesdays from 10 a.m. until 5 p.m. if not

stated otherwise• The labs will be performed in groups of 2 students each• Lab instructions, including descriptions of the experimental setup, the

tasks to be performed and further literature are available for every experiment on the Measurement Techniques website

http://www.msc-ep.uni-bremen.de/services/lectures/Measurement_tech_SS14.html


General Information II

• Please get a copy of the lab instructions from the web at least 2 weeks before the lab takes place

• At least one week before the labs take place contact the lab instructor about the exact time and location of the lab, and perhaps have a first look at the instruments you will use

• For each lab experiment a lab report / protocol has to be written


General information III

• The complete reports have to be handed in 2 weeks after the lab to the tutor

• If the report is not accepted by the lab instructor it can be corrected no more than twice within two weeks after receiving it from the lab instructor

• A special report form will accompany you through the practical and the review process. This form will be given to you during the first lab and has to be handed in at the end of semester

• You will need this report with all signatures to receive the credit points for this course


General information IV

Note:

If you: fail to show up, are not prepared appropriately, submit a revised report which is still not accepted by the instructor

you will have to do an additional experiment at the end of the semester to be admitted for the exam.

Extra experiments can only be done once and should you fail this one also, you will not pass the course.


Safety Considerations

In this set of experiments, you will not be exposed to undue danger by inflammable or hazardous material or ionizing or other harmful radiation. However, you should be aware of some general safety considerations.

Don‘t eat or smoke (this might damage the experiment).

If anything is defect, inform your tutor immediately.

Never construct, modify, or disconnect electrical circuits under voltage

applied.

Never look into laser beams.

Be informed about emergency exits and fire extinguisher sites.

On alert, immediately leave the lab room.

Don‘t cause danger to yourself or anybody else !


The available Experiments

• Satellite Image Analysis

• Natural and man-made radioactivity in soil

• DOAS (Differential Optical Absorption Spectroscopy) measurements of stratospheric species

• Acoustic Current Measurements

• FTS Measurements

• Cavity Ring Down Measurements

• Ozone Absorption Spectroscopy


Prelimiary Time Schedule: Practicals


Experiment / Group A B C D E F G H I JSatellite Image Analysis 25.06. 14.05. 11.06. 28.05. 02.07 21.05.Passive DOAS 14.05. 11.06. 28.05. 25.06. 04.06. 18.06.Radioactivity 28.05. 25.06. 14.05. 11.06. 04.06.Acoustical flow Measurements (Oceanography)

14.05. 11.06. . 28.05. 25.06. 21.05. 18.06.

FTS 11.06. 28.05. 25.06. 14.05. 18.06. Cavity Ring Down Spectroscopy (CRDS)

28.05. 25.06. 14.05. 11.06. 21.05. 02.07.

Ozone Absorption Spectroscopy

28.05. 25.06. 14.05. 11.06. 04.06. 02.07.

Reporting on the experiments

• for each experiment, you will have to submit a report

• students within one group submit joint reports

• after the experiment, you have 2 weeks for writing the report and

submitting it to the tutor

• the tutor will read the report and usually ask for some revisions /

corrections / additions / changes

• you then have another week to submit a corrected report

• if necessary, you will have to submit a second revision

• should the supervisor still not accept your report, this will be discussed

with the lecturers (A. Richter and C. Mertens). If all else fails, you will have

to take another (additional) experiment

• Only with 4 of your reports having been accepted and with a successful

exam you will get the credit points for this course


Contents of the Report

• ideally, your report should enable another scientist to set-up a similar experiment, to repeat the measurements and to compare his results with yours

• it should also give the motivation why things have been done the way they were done

• for the purpose of the practical, it should show that you have understood the experiment

• questions to answer in the report:1.What have you done?

2.Why have you done it?

3.How have you done it?

4.What are the results?

5.What are the associated errors?

6.What are the conclusions?


Structure of Report

1. Title of the experiment; group and name of the students; date

2. Introduction: Short description of the experiment and its objectives

3. Theoretical background: Scientific background on which the experiment is based

4. Experimental set up: Description of the set up used; components and their principle of operation

5. Experimental procedure: Description of each step followed during the experiment, indicating the time and relevant details

6. Data analysis: Description of the data obtained, analysis and conversion procedures applied to obtain the results for interpretation

7. Results and error analysis: Final numerical and graphical results with the corresponding associated error. A detailed description of the error analysis should also be included

8. Discussion of results: Interpretation of the final results in relation to the objectives of the experiment. You can use the questions given in the instructions for the experiment as a guideline

9. Appendix: Raw data in a table, in graphs or in digital form


Use of external sources of information

• in addition to the explanations provided in the experiment description and

lecture, you are expected to use other sources of information (papers,

books, web pages, discussion with your colleagues)

• any information source used must be acknowledged in the text through

appropriate citations

• quoting another text verbatim (“cut and paste”) is usually not acceptable,

and has always to be indicated by using quotation marks

• if you can’t say it in your own words, you have probably not understood it

• quotes from the experiment description are not acceptable

• using data or text from the reports of other groups, or using un-referenced

cut-and-paste text from some internet source, is considered to be fraud


Use of graphical data representations

• Graphical representation of data and results is highly recommended “Ein Bild sagt mehr als 100 Worte”

• All figures must have clear axis labels indicating the quantity plotted and the units used figure captions explaining the contents of the figure figure numbers for reference proper reference and explanation in the text

• figures must be large enough to see all the necessary details• line thickness and symbol sizes must be adequate, colours often help• the ranges used for x and y axis must be appropriate for the range of

values shown• individual measurement points should be shown by symbols• connecting lines should usually be linear, not spline or polynomials • where possible, add error bars


Example for graphical representations

useless

Fig 1: Variation of tropospheric NO2-column with latitude. Data from GEOSCHEM model for July 1997 [Martin et al., 2001] .

useful


Numerical results

• often, a numerical result is expected from your experiment• all numerical results have to be given with units• checking units often helps to find errors• all results must be accompanied by error estimates• the number of digits given must make sense with the errors:

E = 13.45278456 +-2.54378 W m-2 => E = 13.5 +-2.5 W m-2

E = 3E8 +-2.5 W m-2 => E = 31 786 209 +- 2.5 W m-2

• all results should be put into context e.g.is of expected order of magnitudelies within 5% of the predicted valueis twice as large as expected for clean situations


Overall form

• form matters!• use section numbering• use clear section headers• use numbering for equations, figures and tables• don’t forget page numbers• before submitting, check your report for

logic completeness grammar and spelling

• submit your report in a binder and not as a staple of sheets• clearly indicate your names, date of the experiment, date of submission of

report on the cover sheet • reports are prepared with a word processor (word, latex, …)• The length of the report is typically 6 – 8 pages


- 25 -

Final Exam

Type of exam: Oral exam (45 minutes)

Successful completion of all 4 labs

Content: 15 minutes presentation on one experiment

Questions related to the lectures

Questions to the 4 labs

Date: On August 11 - 13, 2014

exact times TBD

Contact:

Andreas Richter Christian Mertens

Room: U-2090 Room: M-3140

Phone: 218-62103 Phone: 218-62147

e-mail: [email protected] e-mail: [email protected]

A. Richter & C. Mertens, Measurement Techniques summer 2014

andreas richter room u2090 tel: 218 62103 e-mail: [email protected]

Documents

measurement techniques

measurement techniques

lab instructor

lab report protocol

general information

general information

general information

revised report