Amgueddfa Blog: Cynaliadwyedd

Blwyddyn Ryngwladol Tabl Cyfnodol yr Elfennau Cemegol y Cenhedloedd Unedig: Mis Hydref – Sylffwr

Christian Baars, 23 Hydref 2019

Yn 2019 mae Tabl Cyfnodol yr Elfennau Cemegol yn 150 mlwydd oed (gweler UNESCO https://www.iypt2019.org/). Mae hyn yn gyfle i feddwl am wahanol agweddau’r tabl cyfnodol, gan gynnwys effeithiau cymdeithasol ac economaidd elfennau cemegol.

Sylffwr yw’r bumed elfen fwyaf cyffredin (yn ôl màs) ar y Ddaear, ac mae’n un o’r sylweddau cemegol gaiff ei ddefnyddio fwyaf. Ond mae sylffwr yn gyffredin tu hwnt i’r ddaear: mae gan Io – un o leuadau Galileaidd y blaned Iau – dros 400 o losgfynyddoedd byw sy’n lledaenu lafa llawn sylffwr, gymaint ohono nes bod arwyneb y lleuad yn felyn.

Alcemi

Câi halwynau sylffad haearn, copr ac alwminiwm eu galw’n “fitriol”, oedd yn ymddangos mewn rhestrau o fwynau a wnaed gan y Swmeriaid 4,000 o flynyddoedd yn ôl. Câi asid sylffwrig ei alw’n “olew fitriol”, term a fathwyd gan yr alcemydd Arabaidd Jabir ibn Hayyan yn yr 8fed ganrif. “Brwmstan” oedd yr hen enw am sylffwr yn llosgi, ac arweiniodd hyn at y gred fod Uffern yn arogli fel sylffwr.

Mwynoleg

Anaml iawn y gwelir sylffwr pur – mae fel arfer i’w ganfod fel mwynau sylffid a sylffad. Mae sylffwr elfennol i’w weld ger ffynhonnau poeth, daeardyllau hydrothermol ac mewn ardaloedd folcanig lle gellir ei fwyngloddio, ond prif ffynhonnell sylffwr ar gyfer diwydiant yw’r mwyn haearn sylffid, pyrit. Ymysg mwynau sylffwr pwysig eraill mae sinabar (mercwri sylffid), galena (plwm sylffid), sffalerit (sinc sylffid), stibnit (antimoni sylffid), gypswm (calsiwm sylffad), alwnit (potasiwm alwminiwm sylffad), a barit (bariwm sylffad). O ganlyniad, mae’r cofnod Mindat (cronfa ddata wych ar gyfer mwynau) ar gyfer sylffwr yn un go hir: https://www.mindat.org/min-3826.html.

Cemeg

Mae sylffwr yn un o gyfansoddion sylfaenol asid sylffwrig, gaiff ei alw’n ‘Frenin y Cemegau’ oherwydd ei fod mor ddefnyddiol fel deunydd crai neu gyfrwng prosesu. Asid sylffwrig yw’r cemegyn gaiff ei ddefnyddio amlaf yn y byd, ac mae’n ddefnyddiol yn bron bob diwydiant; gan gynnwys puro olew crai ac fel electrolyt mewn batris asid plwm. Caiff dros 230 miliwn tunnell o asid sylffwrig ei gynhyrchu bob blwyddyn dros y byd.

Rhyfel

Powdr gwn, cymysgedd o sylffwr, siarcol a photasiwm nitrad a ddyfeisiwyd yn Tsieina yn y 9fed ganrif, yw’r ffrwydryn cynharaf y gwyddom amdano. Sylwodd peirianwyr milwrol Tsieina ar botensial amlwg powdr gwn, ac erbyn OC 904 roeddent yn taflu lympiau o bowdr gwn ar dân gyda chatapyltiau yn ystod gwarchae. Mewn rhyfel cemegol 2,400 o flynyddoedd yn ôl, defnyddiodd y Spartiaid fwg sylffwr yn erbyn milwyr y gelyn. Mae sylffwr yn un o gyfansoddion pwysig nwy mwstard, sydd wedi bod yn cael ei ddefnyddio fel arf cemegol ers y Rhyfel Byd Cyntaf.

Fferylliaeth

Mae gan gyfansoddion sylffwrig bob math o ddefnydd therapiwtig, gan gynnwys trin microbau, llid, feirysau, clefyd siwgr, malaria, canser a chyflyrau eraill. Mae llawer o gyffuriau yn cynnwys sylffwr. Ymysg yr enghreifftiau cynnar mae sylffonamidau, “cyffuriau sylffa”. Mae sylffwr yn rhan o sawl gwrthfiotig, gan gynnwys penisilin, ceffalosborin a monolactam.

Bywydeg

Mae sylffwr yn un o elfennau hanfodol bywyd. Mae rhai asidau amino (cystein a methionin; asidau amino yw cyfansoddion strwythurol protein) a fitaminau (biotin a thiamin) yn gyfansoddion organosylffwr. Mae deusylffidau (bondiau sylffwr-sylffwr) yn rhoi cryfder mecanyddol ac anhydoddedd i’r protein ceratin (sydd mewn croen, gwallt a phlu). Mae gan lawer o gyfansoddion sylffwr arogl cryf: mae arogl grawnffrwyth a garlleg yn dod o’r cyfansoddion organosylffwr. Nwy hydrogen sylffid sy’n rhoi arogl cryf i wyau drwg.

Ffermio

Mae sylffwr yn un o’r prif faetholion ar gyfer tyfu cnydau. Mae sylffwr yn bwysig gydag ymlifiad maetholion, cynhyrchu cloroffyl a datblygiad hadau. Oherwydd hyn, mae asid sylffwrig yn cael ei ddefnyddio’n helaeth fel gwrtaith. Mae tua 60% o’r pyrit gaiff ei fwyngloddio yn cael ei ddefnyddio i gynhyrchu gwrtaith – gallech ddweud mai pyrit sy’n bwydo’r byd.

Yr Amgylchedd

Mae anfanteision i ddefnyddio sylffwr: mae llosgi glo ac olew yn creu sylffwr deuocsid, sy’n adweithio gyda dŵr yn yr atmosffer i greu asid sylffwrig, un o brif achosion glaw asid, sy’n troi llynnoedd a phridd yn asidig ac yn difrodi adeiladau. Mae draeniad asidig o fwyngloddiau, un o ganlyniadau ocsideiddio pyrit wrth fwyngloddio, yn broblem amgylcheddol fawr, ac yn lladd llawer o fywyd mewn afonydd ledled y byd. Yn ddiweddar, defnyddiwyd carreg galchaidd yn cynnwys llawer o pyrit fel ôl-lenwad ar gyfer stadau tai o gwmpas Dulyn. Achosodd hyn ddifrod i lawer o dai wrth i’r pyrit ocsideiddio. Cafodd yr achos ei ddatrys gan y “Pyrite Resolution Act 2013” a roddodd iawndal i berchnogion tai.

Cadwraeth Sbesimenau Amgueddfa

Oherwydd bod sylffidau haearn yn fwynau hynod adweithiol, mae’n anodd eu cadw mewn casgliadau amgueddfeydd. Am ein bod ni’n gofalu am ein casgliadau, sy’n cynnwys gwella arferion cadwraeth o hyd, rydym wastad yn chwilio am ffyrdd newydd o warchod mwynau bregus. Mae ein project diweddaraf, ar y cyd â Phrifysgol Rhydychen, yn cael ei gynnal gan ein myfyriwr ymchwil doethurol, Kathryn Royce. https://www.geog.ox.ac.uk/graduate/research/kroyce.html.

Dewch i’n gweld ni!

Os yw hyn wedi codi awydd arnoch i ddysgu mwy, dewch i weld ein sbesimenau sylffwr a pyrit yn Amgueddfa Genedlaethol Caerdydd. amgueddfa.cymru/caerdydd, neu gallwch ddysgu am fwyngloddio a diwydiannau tebyg yn Big Pit Amgueddfa Lofaol Cymru https://amgueddfa.cymru/bigpit/ ac Amgueddfa Lechi Cymru https://amgueddfa.cymru/llechi/.

The Natural Dye Garden’s Contribution to the Economic Botany Collection

Helen Fogden , 19 Awst 2019

This is a community project led by volunteers from Dre-fach Felindre Gardening Club in conjunction with the National Wool Museum and involving the local primary school’s Eco group. The main aim is to provide a sustainable attractive garden using plants that traditionally have been used for their natural dyes. The plant materials are harvested and used in the end of season workshops.

Early in 2019, the Natural Dye Garden Group was approached by Dr Nicol, of the Sustainable Places Research Institute, Cardiff University, regarding the Economic Botany Collection. This is held in National Museum Cardiff.

Dr Nicol had met with the group some time previously to help explore how this collection of 3,500 specimens might support the public’s understanding and valuing of biodiversity. These specimens were wide ranging but only included one specimen of dye plant material from the UK.

The Museum asked if the Natural Dye Garden Group could provide a contribution to the Economic Botany Collection to expand the range of dye plants held. We were delighted to be able to help.

Every year plant materials from the Natural Dye Garden are harvested and stored for use in the natural dye workshops. From this resource it was possible to provide 13 specimens, labelled and boxed for the Economic Botany Collection.

Additionally, another box was prepared of corresponding dyed samples of wool fibre. In all, 20 colours were included, as examples of colour modifications were added such as yellow from weld overdyed with blue from woad to make green.

These boxes have significantly expanded the natural dye plant selection of the Economic Botany Collection and have all been grown on the National Wool Museum site here in West Wales.

Time to chill

Christian Baars, 2 Awst 2019

One of the best reasons for housing heritage collections inside buildings is that the building keeps the weather out. Paintings, fossils, books and skeletons are best kept dry, and walls and roofs protect our collections (as well as staff and visitors) from the elements.

In addition, many of the objects in our collections also need specific temperature and humidity ranges to prevent them from suffering damage. Too high a humidity can cause swelling of wood, for example, initiating cracks in objects, or, if humidity gets even higher, mould growth. Therefore, National Museum Cardiff has a complicated air conditioning system. This system is more than 40 years old and has been maintenance-intensive and inefficient for some time.

We are happy to report that, after several years of planning, we have just completed the installation of new chillers and humidifiers at National Museum Cardiff. The purpose of chillers in the museum is to provide cold water – for lowering the temperature of galleries and stores in the summer, and for dehumidifying stores and galleries if there is too much moisture in the air. Humidifiers achieve the opposite effect: they increase humidity in stores and galleries if it is too low. Low humidity is usually a problem during the winter months – you may have experienced your skin drying out at home when you have the heating on in winter. To prevent our collections drying out we cannot apply skin cream; instead, we maintain a minimum level of humidity in stores and galleries.

The chillers and humidifiers have been commissioned now, and are working well. They have already proved that the control of our indoor environments is better than it was before. A very positive side effect of the new technologies is that they are much more efficient than the old equipment. In fact, they are so efficient that we are anticipating to shave almost 50% off our annual electricity bill for National Museum Cardiff, saving the planet more than 500 tonnes of carbon dioxide every year. That is the equivalent of taking 100 cars off the road, or the average energy a family home uses in 38 years.

By investing in such new technologies, Amgueddfa Cymru – National Museum Wales continues to ensure the safe storage and display of the nation’s heritage collections, whilst at the same time making a massive contribution towards the National Assembly’s commitment to reduce carbon emissions by 80% by 2050 (Environment Wales Act 2016).

Find out more about Care of Collections at Amgueddfa Cymru - National Museum Wales here and follow us on Twitter. Follow the progress of the maintenance works during the coming months in 2019 on Twitter using the hashtag #museumcare.

 

 

SECRET GARDEN: Brian’s Story

Brian, Volunteer , 26 Mehefin 2019

My name is Brian and I live in Talbot Green. When I was in school I used to do gardening in Y Pant. In the winter I used to help my dad in the garden.

I worked in Remploy in Tonyrefail for ten years starting in 1974. We used to do all sorts of jobs. Then I did four years in Llantrisant, and twenty five years in Porth. On Fridays we finished early and went to the pub for lunch. I retired in 2013. I have the opening plaque from when Remploy opened in Porth in 1988. The building has been demolished.

Since I retired I have done a computer course and a photography course. I have also done pottery and pop art, and I have a big collection of paintings that I have done.

I came to the Take Charge coffee morning in August 2018 and found out about the chance to help at The Secret Garden at St Fagans National Museum of History. That’s when I decided to start gardening again. I’ve learned about teamwork, we work here in a team.

I enjoy doing it, I feel happy. I look forward to coming out and abought especially. I feel tired after, but good tired. My favourite job is raking. I’ve learnt that I enjoy volunteering.


The Secret Garden is maintain and developed by Innovate Trust whose main work is to support people with learning disabilities, mental health issues and people with physical impairments.

 

Your national museum is changing - from the inside out

Christian Baars, 9 Mawrth 2019

Were you amongst among the record number of people who enjoyed our recent ‘Tim Peake’ and ‘Leonardo da Vinci’ exhibitions at National Museum Cardiff? Did you realise that, while you were in the public galleries, there were workers with hard hats and power tools working to improve the building?

We are currently undertaking a large amount of maintenance works in the museum. We do this in such a way to minimise the disturbance to our visitors as much as possible. We want you to enjoy your experience at the museum and be inspired. During the coming months, however, scaffolding will be erected around parts of the building. We are also going to get a temporary over roof on the oldest part of the museum.

Given that this part of the building was opened as long ago as April 1927 by King George V it is now due some tender loving care. Owing to the ravages of time, the roof has developed a few leaks which we are going to repair this year. This also involves having to close some galleries temporarily, for example the Ceramics and Photography galleries. We do apologise for the inconvenience, but these closures are necessary to allow us to undertake the work on the roof and associated internal works.

Galleries will reopen refreshed in the Autumn of 2019, once the works are completed. The brilliant news is that we will be able to present exhibitions without having to worry about a leaking roof. Associated electrical rewiring will also reduce the fire risk in the museum.

Other works we are undertaking - unbeknown to most people as these are happening in our basement - are further electrical works and substantial improvements to our air conditioning systems. This includes the installation of new air conditioning equipment to replace old equipment which will make the museum much more environmentally sustainable.

We are undertaking these works, with kind support of Welsh Government, to protect the Welsh national collection. We constantly strive to improve the way we care for the three million objects housed at National Museum Cardiff. The collections allow us to refresh displays regularly and put on exhibitions with new themes – check out our new ‘People and Plants’ exhibition of the museum’s economic Botany collection. Collections are also used for research, study, teaching, commemoration and many other functions.

Hence, there are many reasons why we would want to do our best to preserve the collections as best we can. The maintenance works during the coming months will greatly assist us with our collection care and, if these occasionally impact on our public spaces, we do ask that you bear with us – the works are temporary but the benefits will be long-lasting.

Find out more about Care of Collections at Amgueddfa Cymru - National Museum Wales here and follow us on Twitter. Follow the progress of the maintenance works during the coming months in 2019 on Twitter using the hashtag #museumcare.