Resumo: A qualidade da água é muito importante para a irrigação por gotejamento, onde escoa por pequenos orifícios que podem ser obstruídos devido à deposição dos sólidos em suspensão; portanto, antes da instalação do projeto devem-se avaliar parâmetros de qualidade da água e manejo a serem implantados, para adotar medidas preventivas, evitando o risco de entupimento do sistema. Dentro desse contexto, este trabalho teve como objetivo avaliar um sistema composto por aeradores com aspersores sobre leito de pedra, para precipitação dos íons Fe+2 e Mn+2 em tanque de decantação e de um conjunto de filtragem composto por três filtros de areia e um de disco, em sistema de irrigação localizada. O trabalho foi realizado na Fazenda Alvorada, no município de Nova Granada - SP, no período de março a outubro de 2008, realizando-se determinações físicas e químicas da água, ao longo do sistema de aeração, decantação e filtragem. Verificou-se que tal sistema foi eficiente para a melhoria da qualidade de água, reduzindo os níveis de risco de entupimento de severo para médio e os de médio para baixo. Oxigênio dissolvido, condutividade elétrica, pH, Fe+2 e Fe+3 não diferenciaram a qualidade de água entre os pontos do sistema de tratamento, porém a turbidez, sólidos dissolvidos, sólidos em suspensão, ferro total e manganês total reduziram-se significativamente pelo uso do sistema proposto. De maneira geral, a qualidade da água utilizada para irrigação variou durante as diferentes épocas do ano, sendo que o risco potencial de entupimento dos gotejadores só foi médio ou alto com relação aos teores de sólidos suspensos, sólidos dissolvidos e ferro total. / Abstract: Water quality is very important for drip irrigation, which flows by small holes that can be clogged due to deposition of solid matter, so before installation of the project some parameters should be evaluated of water quality and management to be established, to adopt preventive measures, avoiding the risk of clogging the system. Within this context, this work was to evaluate a system with sprinklers aeration on bed of stone, for precipitation of ions Fe+2 and Mn total in sedimentation tank and retention in the filter set composed of three sand filters and other disk filter, in drip irrigation system. The work was conducted at Alvorada Farm, at the city of Nova Granada - SP, in the period of March to October of 2008, physical and chemical determinations of water were taken through the system of aeration, sedimentation and filtration. It was found that this system was effective for improving water quality, reducing the risk levels from severe clogging to the medium and from medium to low. Dissolved oxygen, electrical conductivity, pH, Fe+2 and Fe+3 indicates no differences on the water quality between the points of the treatment system, but the turbidity, dissolved solids, suspended solids, total iron and total manganese were significantly reduced by the use of proposed system. In general, the water quality used for irrigation varied during the different seasons, and the potential for clogging of the drippers was medium or high relative to levels of suspended solids, dissolved solids and total iron. / Orientador: José Renato Zanini / Coorientador: Jairo Osvaldo Cazetta / Banca: José Renato Zanini / Banca: Marcilio Vieira Martins Filho / Banca: Raimundo Leite Cruz / Mestre

A água é um recurso natural essencial para a vida, sendo sua qualidade, uma característica extremamente importante para avaliar as possibilidades de seu uso. O presente estudo teve como objetivo avaliar a qualidade da água do complexo de represas Paraibuna-Paraitinga, classificado como corpo dágua Classe 2, localizadas na Bacia do Rio Paraíba do Sul, no Estado de São Paulo. Foram apresentados os resultados das análises dos parâmetros limnológicos: temperatura do ar, temperatura da água, condutividade elétrica, oxigênio dissolvido, pH, transparência, turbidez e sólidos totais; das concentrações dos ânions: nitrato, fluoreto, sulfato, fosfato e cloreto; e das concentrações de elementos-traço: Hg, Se, As, Sb, Pb, Cd, Ag, Al, B, Ba, Be, Co, Cr, Ca, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Si, Sn, Sr, Ti, V e Zn, obtidos a partir das amostras de água de superfície, meio e fundo da coluna dágua, representativas de oito estações de amostragem. Os resultados foram comparandos com os limites estabelecidos na Resolução CONAMA 357/2005. Dos 30 elementos analisados, somente Alumínio, Ferro, Fósforo, Prata e Manganês apresentaram concentrações acima dos padrões legais, principalmente nos períodos chuvosos. Os paramêtros limnológicos ficaram dentro dos padrões para ambientes oligotróficos, como as represas são classificadas. As espécies iônicas apresentaram a maioria dos resultados abaixo dos limites de quantificação e abaixo da legislação. A partir dos resultados obtidos, infere-se que as represas Paraitinga e Paraibuna encontram-se preservadas, e estão isentas de contaminação por metais e elementos-traço, associando as concentrações de Al, Fe, P, Ag e Mn à característica geológica da região. / Water is a natural resource, essential to life, and its quality, an important feature to evaluate the possibilities of its use. This study aimed to evaluate the water quality of the Complex Paraibuna-Paraitinga, classified as Class 2 water body, located in the basin of Paraíba do Sul River, State of Sao Paulo. In order to analyze the water quality of these reservoirs, this paper presents an analysis of some limnological parameters: air temperature, water temperature, electrical conductivity, dissolved oxygen, pH, transparency, turbidity and total solids; the concentrations of anions: nitrate, fluoride, sulfate, phosphate and chloride; and concentrations of trace elements: Hg, Se, As, Sb, Pb, Cd, Ag, Al, B, Ba, Be, Co, Cr, Ca, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Si, Sn, Sr, Ti, V and Zn, obtained from samples of surface water, middle and bottom of water column, representing eight sampling stations. The results were compared with the limits established by CONAMA Resolution 357/2005. From the 30 elements analyzed, only aluminum, iron, phosphorus, silver and manganese concentrations were above the legal standards, especially in rainy periods. The limnological parameters were within the standards for oligotrophic environments, such as these reservoirs are classified. The ionic species present most results below the quantification limits and under the legislation. From the results obtained, it appears that the reservoirs Paraibuna and Paraitinga are preserved, and are free of contamination by metals and trace elements, suggesting that the concentrations of Al, Fe, P, Ag and Mn are linked to the geological feature of the region.

No description available.

Orientador: Mário Alexandre Coelho Sinhoreti / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-22T06:42:26Z (GMT). No. of bitstreams: 1 Vitti_RafaelPino_D.pdf: 971338 bytes, checksum: 04747212bf9b8bde6e4a37081ac788e6 (MD5) Previous issue date: 2013 / Resumo: Os objetivos neste trabalho foram (1) avaliar e comparar propriedades físico-químicas de cimentos endodônticos, sendo um recentemente desenvolvido à base de mineral trióxido agregado (MTA Fillapex, Angelus, Londrina, Brasil) e outro à base de resina epóxica (AH Plus, Dentsply, Konstanz, Alemanha); e (2) desenvolver e avaliar propriedades físico-químicas de três cimentos endodônticos experimentais à base de MTA e uma resina de salicilato com diferentes fosfatos de cálcio (CaP). Os materiais foram manipulados de acordo com as instruções dos fabricantes. Os cimentos experimentais foram compostos de pastas bases e catalisadoras misturadas em 1:1. A pasta base foi composta de 60% de óxido de bismuto e 40% de butilenoglicol dissalicilato. Três diferentes pastas catalisadoras foram formuladas contendo: (1) 60% de MTA, 39% de Resimpol 8 e 1% de dióxido de titânio; (2) 40% de MTA, 39% de Resimpol 8, 20% de hidroxiapatita e 1% de dióxido de titânio e; (3) 40% de MTA, 39% de Resimpol 8, 20% de fosfato dibásico de cálcio diidratado e 1% de dióxido de titânio. MTA Fillapex foi usado como controle. O tempo de trabalho e escoamento foi testado de acordo com a ISO 6876:2001 e o tempo de presa de acordo com a ASTM C266 (n=3 para cada material e teste). Os materiais foram colocados em moldes de PVC (8 mm x 1,6 mm) e armazenados em recipientes contendo 20 ml (testes de solubilidade e absorção de água) ou 10 ml (ensaios de pH e liberação de cálcio) de água deionizada a 37ºC (n=10 para cada material e teste). Em 1, 7, 14 e 28 dias as amostras foram removidas dos recipientes e secas para aferiação da solubilidade e absorção de água. Após 3 e 24 horas e 4, 7, 14 e 28 dias, a água dos recipientes foi coletada para análises do pH e liberação de cálcio. Os dados foram analizados usando ANOVA um fator e teste de Tukey (5%). MTA Fillapex mostrou menores valores de escoamento e tempos de trabalho e presa em relação ao AH Plus (p<0,05). MTA Fillapex obteve os maiores valores de escoamento e tempos de trabalho e presa em comparação aos materiais experimentais (p<0,05). MTA Fillapex apresentou os menores valores de solubilidade e absorção de água (p<0,05). Todos os cimentos experimentais e o MTA Fillapex apresentaram pH básico e liberação de íons cálcio. MTA Fillapex e AH Plus mostraram valores de acordo com a ISO 6876:2001. Os materiais experimentais apresentaram propriedades físico-químicas satisfatórias / Abstract: The aims of this study were (1) to evaluate and to compare physicochemical properties of endodontic sealers, a recent calcium-silicate based sealer (MTA Fillapex, Angelus, Londrina, Brazil) and other an epoxy resin based sealer (AH Plus, Dentsply, Konstanz, Germany); and (2) to develop and to evaluate physicochemical properties of three experimental root canal sealers made by mineral trioxide aggregate (MTA) and a salicylate resin with different calcium phosphates (CaP). The materials were handled following the manufacturer's instructions. The experimental materials were composed of a base and a catalyst pastes mixed in a 1:1. The base paste was made by 60% bismuth oxide and 40% butyl ethylene glycol disalicylate. Three different catalyst pastes were formulated with: (1) 60% MTA, 39% Resimpol 8 and 1% titanium dioxide; (2) 40% MTA, 39% Resimpol 8, 20% hydroxyapatite and 1% titanium dioxide and; (3) 40% MTA, 39% Resimpol 8, 20% dibasic calcium phosphate dihydrate and 1% titanium dioxide. MTA Fillapex was used as control. The working time and flow were tested according to ISO 6876:2001 and the setting time according to ASTM C266 (n=3 for each material and test). The materials were placed into PVC molds (8 mm x 1.6 mm) and stored in containers with 20 mL (solubility and water absorption tests) or 10 mL (calcium release and hydroxyl ions tests) of deionized water at 37°C (n=10 for each material and test). At 1, 7, 14 and 28 days the samples were removed from the solutions and dry for solubility and water absorption tests. After 3 and 24 h and 4, 7, 14, 28 days the soaking water was collected for Ca and pH analysis. The data were analyzed using one-way ANOVA with Tukey's test (5%). MTA Fillapex showed lower values of flow and working and setting times when compared to AH Plus (p<.05). MTA Fillapex had the higher values of flow and working and setting times when compared to experimental materials (p<.05). MTA Fillapex presented the lowest values of solubility and water absorption (p<.05). All experimental cements and MTA Fillapex showed basifying activity and released calcium ions. MTA Fillapex and AH Plus showed values in according to the ISO 6876:2001. The experimental materials showed satisfactory physicochemical properties / Doutorado / Materiais Dentarios / Doutor em Materiais Dentários

Orientador: Luís Roberto Marcondes Martins / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-27T03:21:27Z (GMT). No. of bitstreams: 1 Santos-Caldeira_MilenaMariaPierre_D.pdf: 2166037 bytes, checksum: 223155da07d2c223b86bb075bcb388de (MD5) Previous issue date: 2015 / Resumo: Dentro da abordagem minimamente invasiva da doença cárie, um material resinoso a base de metacrilatos, denominado infiltrante Icon® (DMG), foi apresentado com objetivo de paralisar lesões cariosas incipientes em esmalte pela penetração e polimerização dentro das mesmas. Para análise deste material, os objetivos do presente estudo foram: 1) avaliar a influência do pré-aquecimento (AQ) nas propriedades grau de conversão (GC), resistência à flexão (RF), módulo de elasticidade (ME), dureza Knoop (KN) e redução percentual de dureza (RD) de Icon®; e, 2) avaliar a influência do envelhecimento (EN) nas propriedades rugosidade superficial (RS), KN, RF e ME de Icon®. Para avaliação do efeito de AQ (n=10), corpos de prova foram confeccionados (7x2x1mm) de acordo com os grupos divididos em: G1, Icon sem aquecimento; G2, Icon pré aquecido em estufa a 37oC por 1h; G3, Icon com aplicação de ar frio (23oC) por 20 s; G4, Icon com aplicação de ar quente (40oC) por 20 s. GC foi avaliado através da Espectroscopia por Infravermelho Transformada de Fourier (FTIR). RF e ME foram obtidos pelo teste de resistência à flexão de 3 pontos, em máquina de ensaio universal a 0,5mm/min. KN foi avaliada pela média de 3 indentações sob carga de 50g por 15s, e, RD foi avaliada por KN após imersão dos corpos de prova em etanol por 24h. Os dados para avaliação de AQ foram submetidos a ANOVA um critério (5%). Para avaliação de EN (n=20), amostras do infiltrante foram confeccionadas (7x2x1mm) e armazenadas em saliva artificial, a 37oC, até o momento das análises. O fator tempo foi avaliado, nos mesmos espécimes, em 3 níveis (24h, 6 meses e 12 meses) para RS e KN; porém, para RF e ME, tempo foi avaliado em 2 fases (24h e 12 meses) em espécimes distintos devido ao teste destrutivo utilizado. RS foi avaliada, em 24h, 6 e 12 meses, pela média de 3 leituras Ra em rugosímetro. KN foi avaliada em 24h, 6 e 12 meses como previamente descritos para AQ. Enquanto, RF e ME foram avaliados em 24h e 12 meses como também descrito para AQ. Os dados de RS e KN foram submetidos à análise de medidas repetidas e teste de Tukey, enquanto que os dados de RF e ME foram submetidos a ANOVA um critério (5%). O aumento da temperatura do material Icon, não mostrou nenhuma melhora em relação a GC, RF, ME, KN e RD pelos diferentes métodos de preparo testados. Após envelhecimento, RS aumentou significativamente da análise comparado a 6 e 12 meses, enquanto KN sofreu redução nos mesmos 3 tempos testados, havendo correlação inversamente proporcional entre estas propriedades de Icon®. Adicionalmente, houve redução significante de RF e ME após envelhecimento de Icon®. Desta forma, pode-se concluir que o aquecimento do material não interferiu nas propriedades testadas, e o envelhecimento deteriorou as propriedades do infiltrante / Abstract: Within the minimally invasive approach to caries, a methacrylates based material, Icon® infiltrant (DMG), was presented in order to paralyze incipient enamel carious lesions by penetration and polymerization inside caries lesions. For material analysis, the aims of this study were: 1) to evaluate the effect of pre heating material (HE) in conversion degree (CD), flexural strength (FL), elastic modulus (EM), Knoop hardness (KN) and softening ratio (SR); and, 2) to evaluate the effect of artificial aging (AG) in surface roughness (SU), KN, FL and EM. For HE evaluation (n = 10), 10 specimens were prepared (7x2x1mm) according to the groups that were set up as follows: G1, unheated Icon; G2, preheated Icon in oven at 37°C for 1h; G3, Icon with cold air application (23°C) for 20s; G4 Icon with heated air application (40°C) for 20s. CD was measured by Fourier Transform Infrared spectroscopy (FTIR). FL and EM were evaluated by three-point bending test using an universal testing machine by 0,5mm/min. KN was assessed by three indentations average on load of 50g for 15s. And crosslink density was indirectly assessed by hardness softening ratio after ethanol immersion for 24h. The HE evaluation data were submitted to one-way ANOVA (5%). For AG evaluation (n = 20), samples were prepared (7x2x1mm) and stored in artificial saliva at 37°C until the analysis time. The time factor was evaluated in the same specimens, on 3 levels (24h, 6 months and 12 months) for SU and KN; however, for FL and EM, the time was evaluated in 2 levels (24h and 12 months) at different specimens because of the destructive testing. SU was evaluated at 24h, 6 and 12 months, by 3 readings roughness average (Ra cut-off). KN was assessed at 24h, 6 and 12 months, as previously described for AQ. FL and EM were evaluated at 24h and 12 months as well as described for AQ. Data from SU and KN were submitted to repeated measures analysis and Tukey test, while FL and EM data were submitted to one-way ANOVA (5%). Hight temperature did not improved CD, FL, EM, KN and SR by different prepare methods tested. Aging significantly increased SU from the initial analysis compared to 6 and 12 months, while KN decreased in the same three times tested, with inverse correlation between the properties. There was a significant FL and EM reduction after material aging. Therefore, it can be concluded that heating did not affect material properties tested, however, aging deteriorated infiltrant properties / Doutorado / Dentística / Doutora em Clínica Odontológica

Thesis (Ph.D. (Physics)) -- University of Limpopo, 2021 / Titanium dioxide is among the most abundant materials and it has many of interesting physical and chemical properties (i.e., low density, high thermal and mechanical strength, insensitivity to corrosion) that make it a compound of choice for electrodes materials in energy storage. There are, however, limitations on the theoretical side to using the main electronic structure theories such as Hartree-Fock (HF) or densityfunctional (DFT) especially for large periodic and molecular systems. The aim of the theses is to develop a new, widely transferable, self-consistent density functional tight binding SCC-DFTB data base of TiO2, which could be applied in energy storage anodes with a large number of atoms. The TiO2, LiTiO2 and NaTiO2 potentials were derived following the SCC-DFTB parameterization procedure; where the generalized gradient approximation (GGA) and local density approximation (LDA) exchange-correlation functional were employed yielding Slater-Koster DFTB parameters. The results of derived parameters were validated by being compared with those of the bulk rutile and brookite polymorphs. The structural lattice parameters and electronic properties, such as the bandgaps were well reproduced. Most mechanical properties were close to those in literature, except mainly for C33 which tended to be underestimated due to the choice of exchange-correlation functional. The variation of the bulk lattice parameter and volume with lithiation and sodiation were predicted and compared reasonably with those in literature. The newly derived DFTB parameters were further used to calculate bulk properties of the anatase, which is chemically more stable than other polymorphs. Generally, the accuracy of the lattice structural, electronic and mechanical properties of the bulk anantase were consistent with those of the rutile and brookite polymorphs. Furthermore, nanostructures consisting of a large number of atoms, which extend beyond the normal scope of the conventional DFT calculations, were modelled both structurally and electronically. Structural variations with lithiation was consistent with experimental and sodiation tends to enhance volume expansion than lithiation. Anatase TiO2 and LiTO2 nanotubes of various diameters were generated using NanoWrap builder within MedeA® software. Its outstanding resistance to expansion during lithium insertion and larger surface area make the TiO2 nanotube a promising candidate for rechargeable lithium ion batteries. The outcomes of this study will be beneficial to future development of TiO2 nanotube and other nanostructures. Lastly, our DFTB Slater-Koster potentials were applied to recently discovered trigonal bipyramid (TB), i.e. TiO2 (TB)-I and TiO2 (TB)-II polymorphs, which have enormous 1D channels that provide suitable pathways for mobile ion transport. All structural, electronic properties were consistent with those in literature and all elastic properties agreed excellently with those that were calculated using DFT methods. Finally, the bulk structures of the two polymorphs, were lithiated and sodiated versions and electronic and structural properties were studied, together with the lithiated versions of associated nanostructures consisting of a large number of atoms. Generally, the TiO2 (TB)-I structure was found to be mechanically, energetically more stable and ductile than TiO2 (TB)-II. Hence, it will be beneficial to use TiO2 (TB)-I as an anode material for sodium ion batteries (SIB), due to its unique ductility and larger 1D channels. / National Research Fund (NRF), Department of Science and Innovation (DSI), Material Modelling Centre

Yes / Construction and demolition waste (CDW) management and recycling practices are crucial for transitioning to a circular economy. This study focuses on the detailed characterization of CDWs, including hollow brick (HB), red clay brick (RCB), roof tile (RT), concrete (C), and glass (G), collected from seven different sites. The CDWs were characterized based on particle size distribution, chemical composition, and crystalline nature. Pozzolanic activity was evaluated through compressive strength measurements of cement mortars with 20% cement replacement by CDWs at 7, 28, and 90 days. The results showed that clayey CDWs exhibited similar physical/chemical properties and crystalline structures. Compositions of Cs varied significantly based on their original materials. CDWs satisfied the minimum strength activity index for supplementary cementitious materials, with pozzolanic activity influenced by fineness and SiO2+Al2O3 contents. The average strength activity indexes for HB, RCB, RT, C, and G were 84.5%, 86.3%, 83.4%, 80.7%, and 75.8%, respectively. Clayey CDWs contributed to mechanical strength development, while Cs' contribution was related to hydration of unreacted cementitious particles. G exhibited the weakest pozzolanic activity due to its coarser particle size. Overall, CDWs demonstrated suitable properties for use as supplementary cementitious materials in PC-based systems.

No description available.

Forest areas are particularly susceptible to fires, which are often manmade. Too-frequent fires are likely to adversely affect the soil properties as well as vegetation composition, and possibly lead to soil erosion and desertification. One of the most fire affected forest regions in the world is the Mediterranean. Libya, in the Mediterranean region, has soils that are considered to be arid except in a small area called Aljabal Alakhdar (Green mountain), which is the geographic area covered by this study. It is the wettest part of Libya, and has an extensive forest and many agricultural crops. Like other forests in the Mediterranean it has suffered extreme degradation. This is mainly due to people removing fire wood, or sometimes converting forested areas to agricultural use, as well as fires which may alter several soil chemical and physical properties. The purpose of this research was to evaluate the effects of fires on the physical and chemical properties of soil of Aljabal Alakhdar forest in the north-east of Libya. The physical and chemical properties of soil following fire in two geographic areas have been determined, with those subjected to the fire compared to those in adjacent unburned areas in one coastal and one mountain site. Physical properties studied were: soil particle size, soil water content, soil porosity and soil particle density; and chemical properties studied were: soil electrical conductivity (EC), soil pH, soluble and exchangeable Na, K, Ca and Mg, cation exchange capacity (CEC), soluble Cl, CO3 and HCO3, SO4, organic matter, total N and total P. For the first time in Libyan soils, the effect of burning on the magnetic susceptibility properties of soils was also tested. The results showed that except for the soil water content and magnetic susceptibility, fire has not had a clear effect on the soils¿ physical properties, while there has been a strong impact of fire on most of the studied chemical properties. These results have been used to create an index of burning for such soils in each of the geographic areas, as a step towards creating a model which will enable a subset of soil parameters to be used to estimate how recently a site was burned, as well as defining fire severity at a site. / Libyan Government

Biofouling is the undesired biofilm formation on surfaces at a liquid interface that interferes with the affected substrate’s function. It is a ubiquitous problem in many engineered systems in industry. Biofouling causes contamination, essential damage to materials, and impedances to crucial industrial processes. These adverse effects lead to health hazards, gross increase in energy consumption, and significant decrease in overall productivity, all of which result in higher operational costs and environmentally destructive consequences. Interest in discovering effective alternatives to conventional antimicrobial agents has gained momentum. Current anti-biofouling strategies have significant disadvantages, such as the generation of toxic by-products, indiscriminate corrosion of surrounding materials and the environment, and promotion of resistance development. Alternative methods of controlling biofouling are in high demand because present-day solutions are far from sustainable. Plant secondary metabolites are promising candidates as novel biocides because they are (i) highly effective in killing microbes while being non-toxic to humans at antimicrobially active concentrations, and (ii) safer and non-damaging to the natural environment. Herein, antimicrobial efficacies of five plant-derived compounds were assessed against various species of planktonic bacteria as well as biofilms at various maturity stages. Allyl isothiocyanate (AIT) and cinnamaldehyde (CNAD) displayed the greatest inhibitory effects against all planktonic species tested. The minimum inhibitory concentration is defined as the lowest concentration of a substance that inhibits visible microbial growth, and the MBC is defined as the lowest concentration at which 99.9% of the population is killed. AIT yielded MICs of 156.25 mg/L and MBCs of 156.25 to 312.5 mg/L, and CNAD yielded MICs of 78.125 to 156.25 mg/L and MBCs of 78.125 to 312.5 mg/L. Furthermore, 312.5 mg/L AIT and 625 mg/L CNAD successfully reduced > 80% of biofilm adhesion as compared to negative controls. AIT and CNAD were therefore further evaluated extensively. Hindered by their volatile nature and immiscibility, plant secondary metabolites typically do not reach their maximum antimicrobial capacity due to low bioavailability. Thus, they would benefit from being protected and delivered in nano-sized carriers. In this study, mesoporous silica nanoparticles (MSNs) were evaluated as carriers for AIT and CNAD delivery. In one, employment of MSNs as carriers doubled the antibacterial efficacy of free form AIT and increased kill rate of free form CNAD by six times. Furthermore, free form AIT caused ~70% of 60 day-old biofilm to detach, whereas AIT-loaded MSNs essentially removed all of the biofilm. As for CNAD, its free form had no significant effect, whereas CNAD-loaded MSNs caused ~80% reduction in biofilm biomass. MSNs were further engineered to incorporate lactose pore caps to achieve specific, on-command delivery. These MSNs were designed to respond to external stimuli intelligently, with gatekeepers that degrade only in the vicinity of certain target bacteria that are able to metabolise lactose. Capped AIT-loaded MSNs reduced bacterial viability by ~85% as compared to the negative control, while capped CNAD-loaded versions reduced viability by ~40%. This stimuli-triggered MSN delivery technology would be more sustainable than current methods because resistance development would be lowered, and the delivery vehicles could be recycled and reused. Herein, the complete AIT- or CNAD-loaded, lactose-capped MSNs delivery complex proved to be an effective and environmentally conscientious system for killing unwanted bacteria.