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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Problems and solutions of waste handling practices at red meat abattoirs in the Free State province, South Africa

Roberts, H.A. January 2010 (has links)
Published Article / The waste management practices used at red-meat abattoirs in the Free State province for disposal of condemned products generated in abattoirs and the problems associated with the different waste disposal methods were investigated. Problems caused by various products generated at abattoirs. such as abattoir waste water, blood, stomach contents, manure, whole carcasses, fetuses and all products unsuitable for human consumption requiring disposal were identified. Recommended solutions took into account the most effective handling manner, causing minimum environmental pollution, reducing any health risks to communities, and converting condemned products into value-added by-products by changing certain waste management processes / strategies. The handling of waste, specifically of condemned products, at 78 red meat abattoirs was analysed.
362

An evaluation of operational and administrative procedures for health care waste management in public district hospitals of South Africa

Vumase, Sipho Bongane January 2009 (has links)
Submitted in accordance with the requirements for the Doctors Degree of Technology: Business Administration, Durban University of Technology, 2009. / Although there is an abundance of health care waste information in South Africa, not enough studies have been done in public district hospitals particularly in rural areas. Hospitals find it difficult to comply with the minimum requirements of health care waste management guidelines, such as segregation of waste. If hazardous waste gets mixed with non-hazardous waste, waste disposal and treatment become costly. Furthermore, there has been a sharp increase in the amount of waste generated from health facilities. However, there seem to be uncoordinated efforts in each province in dealing with waste problems. The purpose of this study was to evaluate the process of operational and administrative procedures of health care waste management in hospitals. The study was conducted to facilitate the optimisation of waste management. A quantitative approach was chosen for this study because cause and effect relationships can more easily be identified, and the research is more structured and controlled. The project involved an enquiry into the perception of respondents on the procedures used in managing health care waste. Data was collected from 270 respondents out of 27 hospitals in nine provinces of South Africa. The informants were health care waste workers who were either directly or indirectly involved in waste management. A questionnaire was used as a research instrument. Results were analysed statistically using a special package for scientific studies. It has been found that in the midst of financial challenges, hospitals are unable to prioritise and rank absolutely important activities that are necessary to be undertaken to meet minimum requirements of health care waste management as laid out in the health care waste guidelines and directives. Shortages of waste equipment such as trolleys, waste containers, and temporary storage areas were the main challenges facing hospitals. The recommendations set the tone and provide a blueprint that health care managers may consider in facilitating improvement in the management of health care waste.
363

Treatment and reuse of reactive dye effluent from textile industry using membrane technology

Chollom, Martha Noro January 2014 (has links)
Submitted in fulfillment of the academic requirements for the degree of Master of Technology in Engineering: Chemical Engineering, Durban University of Technology. Durban. South Africa, 2015. / The textile industry consumes large volumes of water and in turn produces substantial quantities of polluted effluents. Approximately 30% of reactive dyes used during the textile processing remain unfixed on fibres and are responsible for the colouration in effluents. Various conventional methods are being used to treat textile effluent. However, the disadvantage of these methods is that total colour removal is not achieved and chemical by-products are introduced from the use of chemicals. The water quality produced therefore does not meet the requirement for textile reuse. Membrane based processes provide interesting possibilities of separating hydrolysed dye stuff and dyeing auxiliaries, thereby reducing colouration and COD content. They can be employed to treat reactive dye bath effluent to recover the salts and water for the purpose of reuse. This study aimed at integrating membrane processes into the reactive dye bath of a textile industry. The objectives were to determine the quality of permeate produced in terms of removal of organics, ascertain its reusability for dyeing, investigate the production rate in terms of permeate fluxes and finally to investigate the cleanability and flux recovery of the membranes. Three effluent samples were chosen for this study based on the dyeing recipe; Light shade, Medium shade and Dark shade. Ultrafiltration (UF) and Nanofiltration (NF) membrane processes were employed to treat the reactive dye bath effluents to recover the salts and water. Investigations were conducted firstly with UF as a pre-treatment to NF. Secondly, evaluations were carried out on the performance of two types of NF membranes (SR90 and NF90) in terms of permeate quality and fluxes for the investigated samples. The effect of cleaning on membrane performance was done. A reusability test was carried out on the permeate samples for dyeing. It was found that the use of UF as a pre-treatment yielded an increase in permeate of 5–25% of the NF fluxes and 90% in organics reduction for all treated samples, hence increasing the water recovery. High rejection of ˃90% by NF90 for COD, TOC and colour were obtained for all the treated samples. SR90 rejection was 80–90% for colour and ˃90% for COD and TOC. Salt recovery for NF90 was 60–90% and for SR90 was 40–50%. The reusability tests carried out showed that permeate recycled from NF90 can be used for any section in the textile industry including the most critical such as dyeing on light shades, while that from SR90 can be used for dyeing dark shades only. It was then concluded that membrane based processes can be integrated into the dye bath of the textile process for the purpose of reuse, thereby saving on the cost of chemicals (salts), reducing fresh water usage and reducing the extent of final effluent treatment.
364

An integrated approach to waste and energy minimization in the wine industry : a knowledge-based decision methodology

Musee, Ndeke 12 1900 (has links)
Thesis (PhD)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The importance of waste management is growing rapidly for several reasons. These reasons include the escalating cost of wastewater treatment and cleaning chemicals, an emerging trend of onerous regulatory regime regarding e uent disposal from governments, rising public awareness on the adverse e ects of industrial waste as well as drastic reduc- tion in water resources in the winegrowing regions. In addition, owing to the large energy demand for refrigeration purposes for high quality wine production and rapidly increasing energy costs, the challenges of energy management in the wine industry were also inves- tigated. In order to address these challenges adequately, the solutions were derived via the integration of two disciplines: environmental science (waste and energy management) and computer science (applications of arti cial intelligence). Therefore, the ndings re- ported from this study seek to advance knowledge through the construction of decision support systems for waste and energy management in circumstances where conventional mathematical formalisms are inadequate. In that sense, the dissertation constitutes in- terdisciplinary research on the application of integrated arti cial intelligence technologies (expert systems and fuzzy logic) in designing and developing decision tools for waste and energy management in the wine industry. The dissertation rst presents the domain of interest, where the scope and breadth of the problems it addresses are clearly de ned. Critical examination of the domain data- bases revealed that data, information, and knowledge for waste and energy management in the wine industry are generally incomplete and lack structure overall. Owing to these characteristics, a hybrid system approach was proposed for the development of decision support systems based on fuzzy logic. The integrated decision support systems were de- veloped based on an object-oriented architecture. This approach facilitated the exible design required for waste and energy management-related complex problem-solving. To illustrate the applicability of the o -line decision tools developed, several case stud- ies mirroring on actual industrial practices were considered. These systems were found to be robust and yielded results that were in accordance with actual industrial practices inthe wine industry. Furthermore, they provided intelligent suggestions in scenarios where there was minimal information, and under certain instances they o ered feasible sugges- tions in circumstances where a human novice could have problems in making the right decisions. / AFRIKAANSE OPSOMMING: Die belangrikheid van afvalbestuur neem om verskeie redes vinnig toe. Die redes sluit in die eskalerende koste van afvalwaterbehandeling en skoonmaakmiddels, streng regula- toriese vereistes van regeringskant met betrekking tot die verwydering van uitvloeisels, toenemende openbare bewustheid van die nadelinge e ekte van nywerheidsafval, sowel as die drastiese afname in waterbronne in wynproduserende omgewings. Daarby, a.g.v. die groot energieverbruik wat deur die verkoeling van hokwaliteitwyn vereis word en die snelgroeiende energiekoste, is die uitdagings van energiebestuur in die wynbedryf ook on- dersoek. Ten einde die uitdagings die hoof te kon bied, is oplossings gevind deur die integrasie van twee disciplines: omgewingswetenskap (afval- en energiebestuur) en rekenaarweten- skap (toepassings van kunsmatige intelligensie). Gevolglik is daar deur die bevindinge van die studie gepoog om kennis te bevorder deur die konstruksie van besluitnemingson- dersteuningstelsels vir afval- en energiebestuur onder omstandighede waar konvensionele wiskundige algoritmes ontoereikend sou wees. In die opsig verteenwoordig die proefskrif interdissiplinre navorsing in die toepassing van gentegreerde kunsmatige intelligensieteg- nologie (kundige stelsels en wasige logika) in die ontwerp en ontwikkeling van besluitne- mingshulpmiddels vir afval- en energiebestuur in die wynindustrie. Die proefskrif baken eers die probleemgebied af, waarna die bestek en omvang van die probleme waarop die werk gemik is duidelik gede nieer word. Kritiese ondersoek van die databasisse in die domein het getoon dat die data, informasie en kennis oor afval- en energiebestuur in die wynbedryf in die algemeen onvolledig en gebrekkig gestruktureer is. A.g.v. di eienskappe, is 'n hibriede stelselbeandering voorgestel vir die ontwikkeling van besluitnemingstelsels gegrond op wasige logika. Die gentegreerde besluitnemingsonders- teuningstelsels is ontwikkel op 'n objek-georinteerde argitektuur. Die benadering het die daarstelling van 'n buigsame ontwerp wat benodig word vir komplekse probleemoplossing in afval- en energiebestuur vergemaklik. Om die toepaslikheid van die a ynige besluitnemingshulpmiddels wat ontwerp is, te illustreer, is verskeie gevallestudies wat werklike industrile praktyk uitbeeld beskou. Diestelsels was robuust en het resultate gelewer wat in ooreenstemming was met werklike industrile praktyke in die wynnywerheid. Die kundige stelsels het verder intelligente voorstelle gemaak in scenarios waar daar minimale informasie beskikbaar was, en onder sekere omstandighede het hulle realistiese oplossings voorgestel waar 'n onkundige persoon probleme sou gehad he tom die regte besluite te kon neem.
365

Utveckling av CBC Strap Cutter : Genom att möjliggöra en viss materialseparation tillsammans med en förenklad tömningsprocess

Blåbäck, Ludvig, Khalil, Gilbert January 2016 (has links)
Syfte – Under detta examensarbete har en vidareutveckling av Cyklop Teknik AB:s existerande produkt, CBC Strap Cutter, utförts. Varav det är en maskin som kapar upp emballageband för att minska hur mycket plats avfallet tar upp, speciellt under avfallstransport. Några problemområden hade uppenbarats efter dess introduktion. En av dessa var att tömningen var omständlig då flera onödiga moment behövde utföras innan tömningen kunde ske. Bland annat i form av att lyfta maskinen från avfallstunnan som också vanligtvis agerade som ställning. Sedan efterfrågades en materialsorteringsfunktion, i form av plast och ferromagnetiskt metall, från Cyklop Teknik AB:s håll. Metod – Utförandet av arbetet har fortgått genom att färdigställa en konceptstudie. Först sammanställdes en kravspecifikation [bilaga 1] och ett Gantt-schema [bilaga 3], de var för att ge ett riktmärke för vad som skulle göras och när. Sedan gick arbetet vidare med att göra konkurrensanalyser och förstudier. Det var för att observera hur konkurrenter och närliggande industrier hade löst vissa problemområden. Ytterligare etablerades det att ingen konkurrent hade en liknande produkt som kunde sortera ingående material. Därefter utfördes konceptgenerering i form av bland annat Brainstorming för att lösa de nämnda problemområdena. Vidare har de olika koncepten sållats ut genom direkt feedback samt en metod som kallas ”Concept scoring matrix”. Till sist återstod ett enda koncept som vidareutvecklades i CAD-miljö, specifikt i SolidWorks. Resultat – Det slutliga resultatet var ett resultat som hade delats upp i olika underkomponenter. Dessa var skärande maskin, separeringsmodul, ställning och avfallstunna. Den skärande maskinen var just den delen som kapade upp det ingående materialet och den behölls så snarlik till originalet som möjligt. Det var för att låta Cyklop Teknik AB:s maskinpark och processer vara så lik som det redan var. För separeringen utvecklades en modul som använde sig av en roterande magnettub. Anledningen till det var för att det skulle ge Cyklop Teknik AB möjligheten att sälja konceptet med eller utan sortering utan att något annat påverkades. Samtidigt skulle modulen kunna anpassas och säljas för andra områden där snabb sortering av nämnda material skulle behöva utföras. En ställning har också tagits fram för att förenkla tömningen som var en kritisk del av arbetet. Eftersom inga onödiga moment skulle uppstå i så fall. Samtidigt utformades ett koncept på en avfallstunna som kunde också den underlätta tömningen. Avfallstunnan utformades därför med både hjul och truckspår för att erbjuda stora möjligheter för användaren. En enskild tömningsprocess för enbart den utvecklades också för att möjliggöra tömning när den skulle vara upphöjd av en truck. Begräsningar – Detta projekt har endast tagit fram en prototyp i CAD-miljö som skulle kunna utvecklas vidare. Anledningen till det var den korta tidsramen för projektet. Sedan har inga simuleringar eller uträkningar utförts på konceptet för att verifiera och optimera konceptet på varje område. Likaså var det på grund av den korta tidsramen. Ingen kundstudie utfördes inte heller, utan istället fortgick arbetet med information som fåtts från Cyklop Teknik AB. / Purpose - In this thesis a further development of Cyklop Teknik AB's existing product, CBC Strap Cutter, has been developed. The product is a machine that cuts packaging tape to reduce the amount space the waste takes up, especially during waste transports. Some problem areas had been revealed after the market introduction of the product. One of these problems was that several unnecessary steps had to be performed before the waste bin could be emptied. One of these step was lifting the machine from the waste bin who also acted as a rack of sorts. A material sorting function, for plastics and ferromagnetic metals, was also requested by Cyklop Teknik AB. Method – The work has been performed by completing a concept study. First a requirement specification [appendix 1] and a Gantt chart [appendix 3] was developed to provide a benchmark for what should be done and when. The work that followed thereafter was a competitive analysis supplemented by a pre-study. The purpose of these studies was to observe how the competitors and related industries had solved these and related problems. Results from the studies that was performed made it clear that no competitor had a similar product that could sort the materials. Brainstorming was thereafter performed to develop new ideas as a help to solve the aforementioned problems and to generate new concepts. Furthermore, the most appropriate concepts was selected through direct feedback from Cyklop Teknik AB among others and a method called "Concept Scoring Matrix". Finally one concept remained and was further developed in a CAD environment, specifically in SolidWorks. Results - The final result was a concept that had been divided into different sub-components. These were cutting machine, separation module, rack and waste bin. The cutting machine was the part cut up the input material. This in turn was kept as close to the original machine as possible and only acquired minor adjustments. In doing so Cyklop Teknik AB's manufacturing processes could remain similar as they have been. A module was developed for the separation, it in turn was constructed with a spinning magnetic tube. The reason for this was that it would give the company possibility of selling the concept with or without the sorting module and its function. At the same time the module could be adapted and sold for other areas where fast sorting of said material would need to be performed. A rack has also been developed to simplify the vacating of the waste bin that was a critical part of the work. In doing so there would be no unnecessary moments that had to be performed. A waste bin was also designed with both wheels and forklift slots to facilitate emptying and offer great opportunities for the user. A single emptying process was developed and made it possible to empty the waste bin when it would be hoisted by a forklift. Restrictions - This project has only developed a prototype in CAD that in turn could be developed further. The reason for this was the short time frame that was allocated for the thesis. No simulations or computations were either performed to validate and optimize the concept in each area. Likewise, it was because of the short time frame. No customer study has been conducted, the work has instead been based on the information received from the Cyklop Teknik AB.
366

Evaluation of primary and secondary treatment of distillery wastewaters

Trerise, Margot Alana 03 1900 (has links)
Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2005. / The thesis reports the investigation of various distillery processes and wastewater streams. The aim was to evaluate the processes and thereafter design interventions for improved wastewater treatment at the respective distilleries. An integrated environmental approach was adopted based on the principle that prevention of pollution is the preferred option and end-of-pipe treatment the least favoured option. As such, feed material to the processes was studied to determine whether some of the components that are not required in the distillation process could in fact be removed prior to entering the system. The results indicate that organic constituents such as phenol and tartaric acid could be removed using physico-chemical and biological treatment methods. The treatment of effluent was studied using an Upflow Anaerobic Sludge Blanket (UASB) set-up to determine the reduction in Chemical Oxygen Demand (COD) in the wastewater. Thereafter the UASB treated effluent was exposed to aeration for further treatment. Summary of conclusions • Pretreatment of wine feed material with calcium hydroxide is effective in removal of 98% tartaric acid, 30% COD and a total phenol content of 57%. • Bio-augmentation results showed that the soil inoculum was the most effective treatment method with reductions of 61% COD at a temperature of 30°C, tartaric acid removal of 98% at the same temperature and 25% reduction in total phenol at 26°C. • UASB was effective with soil inoculum and removed approximately 90% of COD although operational problems were experienced and hindered the operation of the plant. • Aeration of UASB effluent further reduced the COD by a further 60% with a total COD reduction of 96% after both UASB and aeration treatment. • Effective reduction of total phosphorus by 70% and the total phenol content by 80% was achieved by UASB treatment followed by aeration.
367

Community-level analysis of the microbiology in constructed wetlands treating distillery effluent

Du Plessis, Keith R. (Keith Roland) 04 1900 (has links)
Dissertation (PhD)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Constructed wetlands have been widely used in the treatment of industrial and domestic wastewater to reduce biological and chemical oxygen demand (BOD and COD), to remove nitrate and enteric viruses as well as to generally improve water quality. Distillery wastewater has a complex character due to high concentrations of sugars, lignins, hemicellulose, dextrins, resins, polyphenols and organic acids, leading to a high COD that may exceed 100 000 mg/L. The potential application for the treatment of distillery wastewater by means of constructed wetlands is relatively unexplored. In 1999 a study was initiated at Distell Goudini distillery, Western Cape, South Africa, to explore the possibility of using constructed wetlands to treat distillery wastewater. It was found that constructed wetlands do have the ability to treat distillery wastewater providing that the influent COD does not exceed 15 000 mg/L for extended periods and the correct substrate material is used. The present study expanded on the above-mentioned study and specifically aimed to provide information on the microbiological controls in wetland systems in an applied sense that may contribute to improved treatment efficiency. Furthermore, this project aimed to contribute to our fundamental understanding of the microbial ecology of constructed wetlands used for the treatment of distillery wastewater. This study revealed that a highly dynamic microbial composition exists within wetlands. Furthermore it was found that wetlands can efficiently remove COD even though a low degree of similarity exists between microbial communities in various zones of the same wetland and those between different wetlands, as well as low similarity between communities sampled from the same zone over time. This demonstrates that it will be difficult to define the ‘ideal’ degradative community in terms of microbiological criteria and serves as a reminder that various indicators should be considered for monitoring system health. Furthermore the shifts in microbial community composition illustrate the ability of microbial communities to adapt to changes in the environment without compromising their functional efficacy. When studying the attached microbial communities within wetland systems it was found that different morphotypes are detected at certain stages of biofilm development while some organisms are present at most phases of biofilm formation. Measurement of CO2 production and dissolved organic carbon (DOC) removal in laboratory scale columns showed that grazing protists had a notable effect on overall microbial activity and that organic loading influenced these predator-prey interactions. Interestingly, increased clogging of pores occurred in the presence of protists, resulting in reduced flow through the porous matrix. Terminalrestriction fragment length polymorphism (T-RFLP) analysis of biofilms on gravel in experimental wetlands indicated that the presence of protists and algae had an effect on the microbial community composition. Scanning electron microscopy (SEM) showed that the presence of algae also had an influence on biofilm structure suggesting that the algae provided labile nutrients that were utilized by the bacterial and yeast members of the community. Finally, augmentation with a commercial mixture or microbial populations isolated from distillery effluent demonstrated that the concentration at which supplements are applied influence degradative efficiency. / AFRIKAANSE OPSOMMING: Kunsmatige vleilande word wêreldwyd gebruik in die behandeling van indusriële en huishoudelike afvalwater om biologiese en chemiese suurstof aanvraag (BSA en CSA) te verminder, om nitrate en ingewandsvirusse te verwyder asook om waterkwaliteit in die algemeen te verbeter. Distilleerafvalwater het komplekse eienskappe as gevolg van hoë konsentrasies suiker, lignien, hemisellulose, dekstrien, harpuis, polifenole en organiese sure, wat lei tot ‘n hoë CSA wat 100 000 mg/L kan oorskry. Daar is tot op hede relatief min studies gedoen oor die potensiële gebruik van kunsmatige vleilande vir die behandeling van distilleerafvalwater. In 1999 is ‘n studie by Distell Goudini distilleeraanleg in die Wes Kaap van Suid Afrika onderneem om die moontlikheid van kunsmatige vleilande vir die behandeling van distilleerafvalwater te bestudeer. Daar was bevind dat kunsmatige vleilande die vermoë het om distilleerafvalwater te behandel gegewe dat die invloeiende CSA nie 15 000 mg/L oorskry nie en dat die regte substraat materiaal gebruik word. Die huidige studie het by die bogenoemde studie aangesluit met die doel om informasie oor die mikrobiologiese kontroles in vleilandsisteme op ‘n toegepaste wyse te voorsien, wat tot verbeterde behandeling doeltreffendheid kan lei. Hierdie studie het verder beoog om by te dra tot ons fundementele kennis van die mikrobiese ekologie van kunsmatige vleilande wat gebruik word vir die behandeling van distilleerafvalwater. Dié studie het bevind dat daar ‘n hoogs dinamiese mikrobiese samestelling binne vleilande bestaan. Daar was verder bevind dat CSA steeds effektief deur vleilande verwyder kan word alhoewel daar ‘n lae graad van ooreenstemming is tussen mikrobiese gemeenskappe in verskeie sones van dieselfde vleiland en verskillende vleilande, asook ‘n lae graad van ooreenstemming tussen gemeenskappe wat in dieselfde sone oor tyd gemonster is. Dit demonstreer dat dit moeilik sal wees om die ‘ideale’ degraderende gemeenskap te vind in terme van mikrobiologiese kriteria en dien as ‘n herinnering dat verkeie indikatore in ag geneem moet word om die welstand van ‘n ekologiese sisteem te monitor. Die verskuiwings in mikrobiese gemeenskapsamestelling illustreer verder die vermoë van natuurlike sisteme om aan te pas by veranderinge in die omgewing sonder om funksionele doeltreffendheid te verminder. Die studie van aangehegte mikobiese gemeenskappe het aangedui dat veskillende morfotipes bespeur kan word tydens sekere fases van biofilm formasie terwyl sekere organismes tydens meeste van die fases teenwoordig is. Die bepaling van CO2 produksie en die verwydering van opgeloste organiese koolstof in laboratoriumskaal kolomme het geïlustreer dat voedende protiste ‘n waarneembare effek gehad op die algehele mikrobiese aktiwiteit en dat die organiese lading hierdie predator-prooi interaksie beïnvloed het. Dit was interessant om te vind dat die teenwoordigheid van protiste die verstopping van porieë aangehelp het en dus tot verlaagde vloei deur die poreuse matriks gelei het. Terminale-restriksie fragment lengte polimorfisme (T-RFLP) analiese van biolfilm op klipgruis in eksperimentele vleilande het aangedui dat die teenwoordigheid van protiste en alge ‘n effek gehad het op die mikrobiese gemeenskapsamestelling. Skandeerelektronmikroskopie (SEM) het bewys dat die teenwoordigheid van alge ook ‘n invloed op biofilm struktuur gehad het wat daarop dui dat alge maklik afbreekbare voedingstowwe aan die bakterieë en giste van die mikrobiese gemeenskap beskikbaar gestel het. Laastens was bewys dat die konsentrasie van toevoeging van ‘n kommersiële mikrobiese mengsel of mikrobiese populasies wat uit afvoer geïsoleer was, die effektiwiteit van degradering kan beïnvloed.
368

Water pollution from metal-finishing industry in Hong Kong

Ma, Yik., 馬奕. January 1996 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
369

Waste management in Hong Kong abattoirs

Yiu, Wing-chun., 姚榮春. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
370

A review of treatment technologies for the environmental management ofabattoir waste

Yuen, Sin-yiu, Florence., 袁善瑤. January 2003 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

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