A two-step simulation methodology is presented that allows a detailed particle model to be used to resolve the complex morphology of aggregate nanoparticles synthesised in a stagnation flame. In the ...first step, a detailed chemical mechanism is coupled to a one-dimensional stagnation flow model and spherical particle model solved using method of moments with interpolative closure. The resulting gas-phase profile is post-processed with a detailed stochastic population balance model to simulate the evolution of the population of particles, including the evolution of each individual primary particle and their connectivity with other primaries in an aggregate. A thermophoretic correction is introduced to the post-processing step through a simulation volume scaling term to account for thermophoretic transport effects arising due to the steep temperature gradient near the stagnation surface. The methodology is evaluated by applying it to a test case: the synthesis of titanium dioxide from titanium tetraisopropoxide (TTIP) precursor. The thermophoretic correction is shown to improve the fidelity of the post-process to the first fully-coupled simulation, and the methodology is demonstrated to be feasible for simulating the morphology of aggregate nanoparticles formed in a stagnation flame, permitting the simulation of quantities that are directly comparable to experimental observations.
This work presents the first systematically derived and thermodynamically consistent mechanism to describe the thermal decomposition of titanium tetraisopropoxide (TTIP). The mechanism is based on an ...analogy between the decomposition of the isopropoxide branches and the decomposition of isopropanol. Flux and sensitivity analyses were used to identify the main reaction pathways in the proposed mechanism as the step-wise release of C3H6 via four-member ring transition states, the successive abstraction of CH3 radicals via C–C bond cleavage followed by hydrogen abstraction to form C = C double bonds, and hydrogen abstraction from the isopropoxide methyl groups followed by the release of C3H6. The final decomposition product was titanium hydroxide, Ti(OH)4. Rate constants were calculated using conventional and variational transition state theories for reactions in the first two pathways. The calculated rates are similar to the rates calculated for the corresponding isopropanol reactions, providing support for the analogy with isopropanol. The mechanism was used to simulate the ignition delay of isopropanol and TTIP. Excellent agreement was observed with experimental data for isopropanol. However, the mechanism over predicted the ignition delay for TTIP. The discrepancy was shown to be unlikely to be caused by the modest difference between the true reaction rates for the TTIP system and those assumed based on the analogy with isopropanol. It was found that the sensitivity of the TTIP decomposition to the presence of water must be caused by additional chemical pathways than the ones given by isopropanol analogy.
The tetragonal crystal structured anatase titanium dioxide (TiO
2
) has been conventionally used as an electron transport layer in emerging solar cells. Conventionally, a high-temperature process ...above 450 °C is indispensable to form crystallized TiO
2
films with a well-defined mesoporous structure. Due to the temperature limitations of the flexible polymer substrates, notably below 150 °C, such a high-temperature process is ineffective for flexible emerging solar cells. Currently, cutting-edge and high-potential solar cells are flexible dye-sensitized and perovskite solar cells which are preeminent in mass production due to their roll-to-roll printing technique. Hence, this study explores a low-temperature synthesis of crystallized TiO
2
layers using the sol-gel method with various precursor concentrations of titanium tetraisopropoxide (TTIP). Then, the crystallized TiO
2
was deposited with a simple yet low-cost spin-coat technique on flexible substrates (ITO/PET). A thorough scrutinization of TTIP concentration is crucial in identifying the potential of TiO
2
films through comprehensive studies of elements aspects of structural, optical and electrical properties. The synthesized TiO
2
films with a TTIP concentration of 0.5 M demonstrated a high porosity microstructure with exceptional transmittance, allowing a large number of photons to penetrate and thereby resulting in an enhanced charge carrier conduction mechanism. In addition, the direct optical bandgap is reduced with increasing TTIP molarity, proving the involvement of particle factors influencing photocatalytic activities. Moreover, electrical analysis proved that all the correlation features resulted in remarkably low sheet resistance and conductivity of 0.4 MΩ/sq and 0.1194 mS/cm, respectively. It can be conjectured from this study that the synthesis of crystallized TiO
2
at low-temperature conditions with a certain TTIP molarity is successful and has resulted in an enhancement of the electron conduction mechanism, particularly for flexible emerging solar cell applications.
Graphical Abstract
Highlights
The TiO
2
layer has been successfully synthesized by the sol-gel technique without the need for a subsequent conventional high-temperature annealing process, which enables the realization of fabrication for flexible emerging solar cells.
A broad range of different titanium tetrapropoxide (TTIP) molarities have been optimized, resulting in sheet resistance comparable to conventional TiO
2
layers subjected to a high annealing process.
Furthermore, detailed studies from various aspects have also been critically analysed in terms of microstructure, optical and electrical properties to analyse the efficient charge carrier conduction mechanism.
Last and foremost, sol-gel synthesized TiO
2
with 0.5 M TTIP has shown remarkable features, paving the way for the fabrication of flexible PSC in the future.
The topic of TTIP and CETA was almost completely suppressed in Croatia.1 Those are very important international agreements which could have far-reaching consequences both for the world and individual ...countries. Maybe Croatia, as well as the EU, is not so much involved in the whole story concerning TTIP. However, CETA is an agreement signed by Canada with the European Union. Therefore, after the approval of the European Parliament, EU provisions, such as the customs policy, can immediately start to apply, which means abolishing duty rates for 99% of the products as early as 1 January 2017. The decision on the CETA conclusion on behalf of Croatia was initiated by the technical Government of Tihomir Orešković at its last session.2 The superficial interpretation of these certainly not harmless agreements is of too little interest to both philosophers and theologians in Croatia, and except for the Centre of Excellence for Integrative Bioethics’3 reaction concerning this question, other philosophical-theological discussions seem to be lacking. The impression is that philosophers and theologians feel these issues do not concern them. In this paper we will try to make clear that the above-mentioned international agreements concern both philosophers and theologians, and that they certainly should, from their field, from the theoretical level, engage in the discussion of the said agreements.
Gotovo je šaptom prošla tema TTIP-a i CETA-e u Hrvatskoj77. Radi se o vrlo važnim međunarodnim sporazumima koji mogu imati dalekosežne posljedice, kako na svijet, tako i na pojedine države. Možda Hrvatska, kao i EU, nije toliko involvirana u cijelu priču kada se radi o TTIP-u. CETA je, međutim, sporazum koji je Kanada potpisala s Europskom unijom, stoga se nakon odobrenja Europskog parlamenta mogu odmah početi primjenjivati odredbe koje su u nadležnosti EU-a, poput carinske politike, a to znači ukidanje carine za 99 % proizvoda već od 1. siječnja 2017. Postupak za sklapanja CETA-e u ime Hrvatske pokrenula je tehnička vlada Tihomira Oreškovića na svojoj posljednjoj sjednici, a za razliku od američko-europskog trgovinskog sporazuma - TTIP-a koji je neslavno propao, CETA je ipak „prošla“. Površno tumačenje ovih nikako bezazlenih sporazuma premalo zanima i filozofe i teologe u Hrvatskoj; osim što se Centar izvrsnosti za integrativnu bioetiku oglasio po ovom pitanju, drugih filozofsko-teoloških rasprava kao da nema. Doima se kako filozofi i teolozi smatraju da se ova pitanja njih ne tiču. U radu ćemo pokušati dati do znanja kako se navedeni međunarodni sporazumi i te kako dotiču i filozofa i teologa, te kako bi se oni iz svog polja na teorijskoj razini svakako trebali uključiti u raspravu o njima.
This paper aims to examine the debate surrounding negotiations of the Transatlantic Trade and Investment Partnership (TTIP). The EU and US began negotiations for this comprehensive commercial ...agreement in July 2013 and have still not reached consensus. This article aims to assess the possibility of resuming talks on this sensitive topic in light of the current administration in the White House, or of the European Union potentially shifting its attention to other global partners, in a period when it is visibly undergoing a number of internal crises.
Cobalt doped titanium dioxide has consumed great consideration because of their photo catalytic activity and numerous utilizations in paints, white pigments and tooth paste. The co-precipitation ...technique was utilized in this present study to produce titanium dioxide nanoparticles using (TTIP) titanium tetra iso-propoxide and cobalt nitrate as a starting precursor. Cobalt doped TiO2nanoparticles were synthesized up to four to seven percent of cobalt composition. The Morphology of nanoparticles, crystal structure and optical characteristics were analyzed by XRD, UV-vis spectroscopy and scanning electron microscopy, respectively. Functional groups of cobalt doped TiO2 nanoparticles were confirmed by Fourier transform infrared spectroscopy (FTIR). The modified cobalt-doped titanium dioxide exhibits increased absorption in UV region as increasing cobalt content. The main purpose of this research is to enhance the photo catalytic activity and observe the dimensions, morphology and cobalt concentration as well as shape of prepared nanoparticles.
Recent trade negotiations such as TTIP include investor protection clauses. Against the background of an analysis of the case for trade, the paper asks whether such clauses can be justified from a ...normative perspective. More specifically, what is the impact of investor protection on the domestic distribution of the gains from trade between labour and capital, and how should we assess this impact from the perspective of justice? In order to answer this question, the paper develops a series of ideal-type scenarios that reflect the consequences of investor protection on employment on the one hand, and on the distributive conflict between labour and capital on the other. While no claim is made which of these scenarios corresponds to TTIP or other trade agreements, they provide a useful normative framework to analyse such agreements.
The challenges of regulating industrial chemicals remain unresolved in the United States. The Toxic Substances Control Act (TSCA) of 1976 was the first legislation to extend coverage to the ...regulation of industrial chemicals, both existing and newly registered. However, decisions related to both law and science that were made in passing this law inevitably rendered it ineffectual. Attempts to fix these shortcomings have not been successful. In light of the European Union's passage of innovative principles and requirements for chemical regulation, it is no longer possible to deny the opportunity and need for reform in US law and practice.
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