21 research outputs found

    Effect of Additives on UV-Activated Urethane Acrylate Polymerization Composite Coatings

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    An increased demand for new and improved coating systems, for environmental & health & safety and performance reasons, have appeared during the recent decades. Currently, there is new interest in preparation of thin UV curable urethane acrylate (UA) composite coatings with short-term properties. Cellulose based additives: nitrocellulose, cellulose acetate butyrate, sucrose benzoate and silica were evaluated to determine their influence on unreacted composite characteristics (viscosity, pigment suspension stability) and characteristics of cured film (ultimate tensile strength, elongation at break, surface gloss, surface scratch resistance and film adhesion loss time). The most suitable additive content was found to provide required viscosity. All additives increase surface scratch resistance, but cellulose based additives increase surface gloss values and decrease the time of adhesion loss. Silica has great effect on the interaction between linear and hyperbranched urethane acrylates, which has crucial influence on the stability of uncured pigmented mixture samples

    Ekodizaina metode Ä·Ä«misko vielu nevēlamas ietekmes uz vidi un cilvēku veselÄ«bu samazināŔanai produkta dzÄ«ves ciklā

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    AugoÅ”s pierādÄ«jumu daudzums par produktu sastāvā esoÅ”o kaitÄ«go Ä·Ä«misko vielu nelabvēlÄ«go ietekmi uz vidi un cilvēku veselÄ«bu liecina par nepiecieÅ”amÄ«bu samazināt Ŕādu vielu saturu produktos un izdalÄ«Å”anos no tiem, ko varētu realizēt ar ekodizaina ā€“ vidi saudzējoÅ”u produktu izstrādes ā€“ palÄ«dzÄ«bu. Pārskatot zinātniskās publikācijas ekodizaina jomā, konstatēts, ka paÅ”reiz ekodizaina metodes nepilnÄ«gi nodroÅ”ina materiālu sastāvā esoÅ”o vielu kaitÄ«gās ietekmes uz veselÄ«bu un vidi novērÅ”anu. Tāpēc radÄ«ta jauna, daļēji kvantitatÄ«va ekodizaina metode, apvienojot produktu izstrādes prasÄ«bas ar zinātniskā Ä·Ä«miskā riska novērtÄ“Å”anas principiem. Metode tiek aprobēta, demonstrējot tās izmantoÅ”anu. Metode ļauj produkta izstrādātājam identificēt pārmaiņu nepiecieÅ”amÄ«bu, un izstrādāt ekodizaina priekÅ”likumus un izvērtēt alternatÄ«vas, turklāt veicinot saziņu par materiālu Ä«paŔībām un ietekmi uz vidi un cilvēka veselÄ«bu izejvielu un produktu piegādes ķēdē. Darba mērÄ·is ir izstrādāt ekodizaina metodi, ar kuras palÄ«dzÄ«bu samazināt Ä·Ä«misku vielu nevēlamo ietekmi uz vidi un cilvēka veselÄ«bu produkta dzÄ«ves ciklā. MērÄ·a sasniegÅ”anai veikti Ŕādi uzdevumi: 1) izstrādāt ekodizaina priekÅ”likumu identificÄ“Å”anas un vērtÄ“Å”anas kritēriju sistēmu, ņemot vērā materiālos esoÅ”o vielu toksiskās Ä«paŔības, atkārtotas izmantoÅ”anas un reÄ£enerācijas iespējas, dizaina parametrus un produkta dzÄ«ves ciklu, 2) izstrādāt pamatprincipus, kā pārbaudÄ«t informāciju par bÄ«stamajām vielām materiālos un Ä·imikālijās, lai nodroÅ”inātu ticamus datus produktu izvērtÄ“Å”anai, 3) aprobēt ekodizaina metodi, eksperimentāli izpētot konkrētus produktus un tā demonstrējot metodes izmantoÅ”anas iespējas un informācijas pieejamÄ«bu. Darba struktÅ«ra un apjoms: darbs sastāv no ievada, četrām nodaļām un secinājumiem, un pielikuma; tajā ir 132 lappuses, 39 attēli, 41 tabula, literatÅ«ras saraksts ar 249 informācijas avotiem. Darba zinātniskā novitāte: izstrādāta jauna ekodizaina metode produktu sastāvā paredzēto Ä·Ä«misko vielu ietekmes samazināŔanai un materiālu atkārtotas izmantoÅ”anas un pārstrādes veicināŔanai, vadoties pēc Ä·Ä«misko vielu bÄ«stamajām Ä«paŔībām, materiāla Ä«paŔībām, produkta dzÄ«ves cikla aspektiem un dizaina parametriem. Metodes zinātniskās novitātes: 1) zinātniskā Ä·Ä«miskā riska novērtējuma principu piemēroÅ”ana ekodizaina, tas ir, produktu izstrādes vajadzÄ«bām, radot jaunu ekodizaina metodi, 2) izveidota Ä·Ä«miskās bÄ«stamÄ«bas un iedarbÄ«bas, kā arÄ« materiālu atkārtotas izmantoÅ”anas un pārstrādes iespēju novērtÄ“Å”anas sistēma, kas ļauj izstrādāt ekodizaina risinājumus produktiem, nodroÅ”inot labāku patērētāju veselÄ«bas un vides aizsardzÄ«bu no produktu sastāvā esoÅ”o toksisko vielu nelabvēlÄ«gās hroniskās iedarbÄ«bas, kā arÄ« mazinot materiālu resursu noplicināŔanu. Promocijas darbs izstrādāts ar Eiropas Sociālā fonda atbalstu projektā ā€œAtbalsts RTU doktora studiju Ä«stenoÅ”anaiā€

    Development Set of Criteria as an Eco-Design Tool for the Evaluation of Environmental Impact of Material Choice

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    Ekodizains ir daļa no produkta izstrādes procesa. Tā mērÄ·is ir samazināt produkta ietekmi uz vidi visā tā dzÄ«ves ciklā. MÅ«sdienās ekodizaina nozÄ«me aizvien pieaug, un likumdevēji Å”o pieeju to iestrādā arÄ« jaunākajos likumdoÅ”anas aktos. Tai paŔā laikā ekodizaina ievieÅ”ana rÅ«pniecÄ«bā kavējas, jo vairums izstrādāto ekodizaina instrumentu un vadlÄ«niju orientējas uz stratēģisko lÄ«meni, bet trÅ«kst praktisku ievieÅ”anas instrumentu. Lai veicinātu ekodizaina ievieÅ”anu rÅ«pniecÄ«bā, nepiecieÅ”ams izstrādāt vienkārÅ”us instrumentus, kas vadās no jaunākajiem zinātniskajiem atklājumiem un padara tos ievieÅ”amus ražoÅ”anā produkta izstrādes procesā. Å Ä« raksta mērÄ·is ir iepazÄ«stināt ar apsvērumiem kritēriju kopas izstrādei materiālu izvēlei, ņemot vērā publicēto dzÄ«ves ciklu analīžu rezultātus un datus par materiālu ietekmi uz vidi. Piedāvātā kritēriju kopa balstās uz trim galvenajiem kritērijiem ā€“ toksiskumu, reciklējamÄ«bu (atkārtotas izmantoÅ”anas spēju), enerÄ£ijas patēriņu, kas atbilst citu zinātnieku publicēto dzÄ«ves cikla anaļīžu pētÄ«jumu rezultātiem. Å ie kritēriji ir saistÄ«ti viens ar otru ā€“ palielinot reciklējamÄ«bu, var samazināt enerÄ£ijas patēriņu un toksisku vielu izkliedi. InovatÄ«va pieeja Å”ajā kritēriju kopā saistās ar to, ka produkta dizains ā€“ produkta struktÅ«ra un izmantoÅ”anas veids ir saistÄ«tts ar reciklējamÄ«bu, toksiskumu un enerÄ£ijas patēriņu. NākoÅ”ais solis kritēriju sistēmas pilnveidoŔānāir kvantificējamu vērtÄ«bu izstrāde (5 vienÄ«bas), lai piemērotu Å”o kritēriju izmantoÅ”anu produkta izstrādes procesā, tas ir, radÄ«tu instrumentu ātra, lai gan virspusēja, pārskata iegÅ«Å”anai

    Chemical Risk Communication from the Ecodesign Perspective: Legislative Preconditions and Needs for More Information than Required by Law

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    Ecodesign or design for the environment is a systematic design approach to reduce environmental impacts of products and to achieve higher protection standards than set by law. The chemicals legislation of the European Union is seen as one of the most advanced in the world regarding protection of human health and environment. REACH - Regulation concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals enhances risk communication on the supply chain and makes a ground for generation of chemicals safety information, e.g., feeds the information needed for communicating chemicalsā€™ risks down the supply stream including classification, labeling and safety data sheets as required by the regulation on CLP (Classification - Labelling - Packaging) according to GHS (Globally Harmonized System of Chemicals). The main responsibility about chemicalsā€™ safety is placed on the industry; however, the most dangerous chemicals are restricted and banned in a transparent and systematic way. Are the risk assessment measures upstream sufficient for the ecodesign? Is it needed to judge upon chemical risks of the non-chemical products during design phase to achieve higher standards for the environmental and human health protection? This study indicates the benefits from the REACH system for the ecodesign, as well as highlights the needs for an enhanced risk communication on the supply chain compared to the current legislative requirements, especially regarding the materials: intended content of chemicals and residues /impurities. For example, in order to demonstrate compliance with environmental labelling criteria, very detailed information about the chemicals contained in materials is required

    Legislative Developments and Ecodesign Tools for Reduction of Chemical Risks

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    LikumdoÅ”ana un ekodizaina paņēmieni ar Ä·imikālijām saistÄ«to risku mazināŔanai. Vides piesārņojums ar Ä·Ä«miskajām vielām vielām ir sasniedzis tādus apmērus, kas pieprasa nekavējoÅ”u rÄ«cÄ«bu. Pasaules samits 2002 gadā formulēja ambiciozu mērÄ·i lÄ«dz 2020 gadam samazināt Ä·imikāliju izsaukto negatÄ«vo ietekmi uz cilvēka veselÄ«bu un vidi. Rakstā apskatÄ«ti svarÄ«gākie normatÄ«vie akti, kas paredz produktu (izstrādājumu) radÄ«to Ä·Ä«misko risku samazināŔanu: REACH (Regula par Ä·Ä«misko vielu reÄ£istrÄ“Å”anu, licenzēm un ierobežojumiem), RoHS (BÄ«stamo vielu ierobežojumu direktÄ«va) un citi. Raksts kā vienu no visefektÄ«vākajām metodēm Ä·Ä«misko vielu riska samazināŔanai piedāvā ekodizainu, ko izmanto produkta izstrādes fāzē, kad ir iespējams izvairÄ«ties no problemātisku materiālu lietoÅ”anas, vai ieviest slēgtas sistēmas ražoÅ”anā. Publikācija analizē esoÅ”os ekodizaina instrumentus attiecÄ«bā uz to potenciālu samazināt produktu (izstrādājumu) radÄ«to Ä·Ä«misko vielu risku un panākt atbilstÄ«bu likumdoÅ”anas prasÄ«bām. Apzinātas likumdoÅ”anas kritiskās vietas, kas neveicina nevēlamu vielu izmantoÅ”anas pārtraukÅ”anu. UzskaitÄ«tas galvenās grÅ«tÄ«bas, kas kavē ekodizaina instrumentu izmantoÅ”anu Ä·Ä«misko risku samazināŔana

    Information System on Substances in Products and Raw Materials as an Important Step to Reach Compliance with RoHS Directive in a Company

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    RoHS directive restricts the use of certain substances in new electric and electronic equipment. Producers as well as importers must be able to demonstrate compliance by technical documentation or other information. A very important step within a compliance strategy is development of an internal information system to ensure the proper documentation. The documentation created internally and provided by suppliers shall fulfil the com-panyā€™s own information needs, as well as satisfy the enforcement authorities. RoHS directive provides no stan-dards for the documentation how to demonstrate compliance. Regarding such raw materials as chemicals, legis-lation like REACH prescribes very clear requirements for information (Safety Data Sheets). With regard to other raw materials, there are no exact rules. On one hand, it gives a room for innovation and free interpretation focus-ing on companyā€™s own needs. On the other hand, it bears certain insecurity whether the information provided is proper and sufficient. It also means that internal standards for elaboration and checking of the documentation provided by suppliers are necessary. The existing situation in Latvia with product declarations regarding RoHS from the perspective of industrial companies and enforcement authorities is analyzed in this article. Main chal-lenges are identified and suggestions for improvement options of product declarations and internal information system are given

    Set of Criteria for Environmentally Sound Material Choice as an Eco-Design Tool

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    Eco-design is a part of a product design process with the aim to reduce the environmental impact of the product during its entire life cycle. Despite of recognition on the strategic level and growing market interest for green products, the practical implementation of eco-design in industry, especially small and medium size enterprises, is slow. One of the reasons is lack of simple and practical tools. An important part of the product design process having considerable consequences for the environment and human health is the material selection. Therefore, we aimed at development of a screening and ranking tool, which would address 3 issues ā€“ toxic dispersion, material use and embodied energy - from a life cycle perspective. The offered set of criteria provide the 5-level grading system expressed in the following words: negligible, low, moderate, high, very high. Development of criteria is based on the following information sources and considerations: ā€¢Criterion on embodied energy of the material is based on information on MJ of energy, necessary for extraction and production of 1 kg of the raw material. Further processing of the material requires some energy as well, but it is usually less than in the initial production, and therefore disregarded. ā€¢Criterion on toxic dispersion is based on information on classification and labelling system (e.g. hazard communication tool enforced by legislation [6]), environmental properties of chemical (mobility, stability), binding to the product matrix, use patterns of the product and end of life scenario. ā€¢Recyclability criterion is based on the inherent recyclability of the material, product design and end of life scenario of the product. This criteria system is utilising information, which shall be available for the producer of the product e.g. article (design, use, potential end of the life scenario), or which can be obtained from suppliers (e.g. properties of chemical substances within materials); however, some information has to be obtained from the publicly available and commercial data basis. The method is universal and applicable for different products; the quantitative results are suitable only for internal use within company. Nevertheless, this criteria system promotes collection of information, which can be valuable for application of other tools and instruments e.g. eco-labelling. Although new EU legislation ā€“ REACH places all responsibility on the supplier of the chemicals (e.g. producer of importer) requesting that all the chemicals placed on the market must be safe for the intended use there is still a place also for producers of articles to screen the chosen materials regarding the content of chemicals since the common legislation usually sets the minimum standards, which might not be sufficient for a company aiming at the products with higher environmental performance or having higher social responsibility. Also, the ā€œsafetyā€ of the materials depends very much on the implementation level of REACH, especially with regard to the imported materials

    When is Green Really Green? A Latvian Case Study on Updating of Food Supply Green Public Procurement

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    Green public procurement (GPP) is an important tool and is used to reduce adverse environmental impacts caused by food production. To have a more detailed look at the application of GPP in Latvia, the authors screened 97 public tenders for supply of food products, documenting the choice of the green criteria. Only 15 % of the screened tender documents corresponded to the national GPP requirements. Only 4 % of the tender documents gave higher priority exclusively for organic products compared to products within national quality schemes or integrated pest management agriculture. The authors compared these findings with the opinions of environmental experts, GPP guidelines by the European Commission, and experience from other countries. The authors conclude that 1) self-reporting is not an appropriate method to measure the implementation level of GPP, and 2) having a large number of criteria without clear goals can lead to using the easiest, but least environmentally beneficial options, and 3) for some tenders complying with national GPP, the environmental benefits may be unclear

    Aspects of the Allocation Problem and Boundary Assessment in Life Cycle Assessment of Latvian Pellet Flow Chain

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    Latvia has increased its own forested area from 44% to 55% in the last 10 years and therefore the crucial position of this renewable source in the energy strategy of the country appears evident. Latvianā€™s energy supply is based on a balanced mixture of energy sources, in which renewable sources are represented with circa 30% in the final energy consumption for the year 2007. The EU directive fixes the target of 40% share of renewable energy resources in the final consumption in 2020. In the light of a constant need to reduce the GHG emissions, with the consequent increase of use of renewable sources, the environmental sustainability is fundamental for future Latvian energy strategies. Life Cycle Assessment (LCA) is one approach that enables the energy requirements, GHG balance and other environmental impacts of bioenergy production chains to be accounted and accurately compared. Hence, LCA seems to be an appropriate tool to provide information on environmental repercussion for analysis regarding the global wood fuel flow chain. Under impulse of the previous statements the primary objective of the work is a study of the environmental impact of the entire Latvian wood fuel flow chain with focus on the woody biomass for final production of thermal energy. The production of thermal energy from wood pellets focusing on the complication derived from allocation and boundary assumptions will be discussed and presented in the paper. A number of different methods for co-product allocation can be found in the literature ranging from no co-product allocation, allocation by price, energy content, mass, or by substitution with the product they might replace. The choice of different wood flow boundaries could affect the precision and consistency of the analysis. The outcome of the sensitivity analysis is focused on how the use of different methodology for the allocation and boundary definition affects the final result

    The Environmental Impacts of a Desktop Computer: Influence of Choice of Functional Unit, System Boundary and User Behaviour

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    Vides politikā aizvien vairāk pieaug vērÄ«ba piesārņojuma novērÅ”anai jau produkta un ražoÅ”anas procesa dizaina (projektÄ“Å”anas) posmā, salÄ«dzinot ar citu, vēsturiski pazÄ«stamāku principu ā€“ piesārņojuma novērÅ”anu Ā«caurules galāĀ». Å Ä«s pieejas Ä«stenoÅ”anai nepiecieÅ”ams paredzēt produkta vai procesa iespējamo ietekmi uz vidi, un arÄ« izvelēties visefektÄ«vakos pasākumus, kā Å”o ietekmi samazināt. Å obrÄ«d Å”im mērÄ·im vispiemērotā metode ir dzÄ«ves cikla analÄ«ze ā€“ metode, ar kuras palÄ«dzÄ«bu uzskaita visas produkta vai procesa radÄ«tās ietekmes uz vidi katrā produkta dzÄ«ves cikla posmā, sākot ar izejmateriālu ražoÅ”anu un beidzot ar atkritumos nonākuŔā produkta otrreizējo pārstrādi vai noglabāŔanu. Tomēr, ja analÄ«zes veicēji izvēlas neatbilstoÅ”u metodiku, vai interpretējot rezultātus, neņem vērā trÅ«kstoŔās informācijas ietekmi, var nonākt pie kļūdainiem secinājumiem. Å eit aprakstÄ«tā pētÄ«juma laikā mēs pētÄ«jām galda datoru ietekmi uz vidi, izmantojot vienkārÅ”otu dzÄ«ves cikla analÄ«zes metodi ā€“ Indikatorusā€™ 99, un izstrādājām vairākus scenārijus (pagarinot produkta dzÄ«ves ilgumu, mainot patērētāja uzvedÄ«bu, enerÄ£ijas piegādi). PētÄ«juma rezultāti liecina, ka pasākumi ietekmes uz vidi mazināŔanai ir veicami dažādās jomās. Funkcionālā vienÄ«ba ir jādefinē pietiekami elastÄ«gi, lai izslēgtu to, ka pētÄ«juma veicēji nepamana svarÄ«gas jomas pasākumu veikÅ”anai. Tāpēc, lÄ«dzÄ«gi citiem autoriem, mēs piekrÄ«tam, ka datora gadÄ«jumā funkcionālā vienÄ«ba var bÅ«tā€ž1 datorsā€, bet neiesakam piesaistÄ«t to pie dzÄ«ves ilguma, vai izmantoÅ”anas laika, tā vietā izstrādajot vairākus scenārijus, mainot Å”os parametrus. PētÄ«jums arÄ« parāda sistēmiskas pieejas nepiecieÅ”amÄ«bu, vērtējot kompleksu produktu sistēmu ietekmi uz vidi. Mēs secinām, ka datoru gadÄ«jumā, kas ir energo- un materiālietilpÄ«gi produkti, pasākumi vides ietekmes mazināŔanai jāveic nevien produktu ražotāja un lietotāja lÄ«menÄ«, bet arÄ« nacionālā lÄ«menÄ«, piemēram, mazinot nacionālās enerÄ£ijas apagādes sistēmas ietekmi uz vidi, kā arÄ« pilnveidojot atkritumu apsaimniekoÅ”anas sistēmu. Uzlabojumi Å”ajās jomās ievērojami var samazināt materiālietilpÄ«gu un energoietilpÄ«gu produktu ietekmi uz vidi
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