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Photograph of Raja Shahid Ali Khan and Abbas Ali Khan
No full textPhotograph of two Nager Burushaski speakers, Raja Shahid Ali Khan (left) and Abbas Ali Khan
Pneumonic Pasteurellosis: Role of Pasteurella multocida and Mannheimia haemolytica in respiratory disease of cattle
No full text<p>Pneumonic Pasteurellosis is an important economically significant infectious diseases of large animals specially ruminants, having a global distribution. It is an acute febrile condition having severe fibrinopurulent or fibrin bronchopneumonia, fibrinous pleurisy, and septicemia characterizes the disease. Many outbreaks has been reported around the World.</p>
Conflict and Education
No full textThe purpose of this research is to study the impact of conflict witnessed in Pakistan from 2007 onwards on educational outcomes, particularly pertaining to female education. It consists of three distinct chapters, each focusing on a unique aspect in which conflict affected educational outcomes. The first chapter deals with the first phase of conflict witnessed between 2007 and 2011, and analyses the impact of violence, and the ban on female schooling implemented with it, on enrolment rates. It suggests that although conflict resulted in a decline in overall enrolment rates at primary and middle level, militants were successful in using violence as a tool to deter female education, as enrolment rates for girls declined more compared to boys in areas that witnessed conflict. The second chapter studies the short-term and medium-term impact of conflict on enrolment rates after the end of the first phase of conflict. Results show that although the negative impact of conflict was larger in magnitude on girls than boys in the short-run, enrolment rates for girls recovered in the medium-run to match those of girls that did not witness conflict. However, enrolment rates for boys at middle level continued to suffer in the medium-run, possibly due to the permanent substitution of boys into the labour market. The third chapter examines the impact of conflict on degree choices of students applying to university. We find that students who live in districts affected by conflict are less likely to apply to degrees that require mathematics as a prerequisite, compared to students who live in districts that do not witness conflict. However, a gender-wise breakup of results suggest that this is only the case for degree choices of boys, and not of girls
Exponentially weighted moving average chart using zero-inflated negative binomial distribution
No full textZero-inflated models are frequently used to deal with data having many zeros. A commonly used model for over-dispersed data containing zeros is known as the zero-inflated Poisson model. However, to account for the heterogeneity of counts that leads to excess variance besides inflation of zeros in the data using a more flexible model than the zero-inflated Poisson model, a zero-inflated negative binomial (ZINB) is suggested. In the present study, Shewhart and exponentially weighted moving average (EWMA) control charts are suggested to monitor the ZINB data. The charts are compared using the average run length and standard deviation of run length by using extensive Monte Carlo simulations. Besides a comprehensive simulation study assuming different settings of parameters of ZINB, a real data set is used to show the practicality of the proposed charts. The results indicate that the EWMA chart is better than the Shewhart chart
Supplementary_material โ Supplemental material for One-pot synthesis of 4-ethyl 2,3-dimethyl 1-(5-aryl-1,3,4-thiadiazol-2-yl)-5-oxo-2,5-dihydro-1<i>H</i>-pyrrole-2,3,4-tricarboxylate derivatives via intramolecular Wittig reaction
No full textSupplemental material, Supplementary_material for One-pot synthesis of 4-ethyl 2,3-dimethyl 1-(5-aryl-1,3,4-thiadiazol-2-yl)-5-oxo-2,5-dihydro-1H-pyrrole-2,3,4-tricarboxylate derivatives via intramolecular Wittig reaction by Samin Iravani and Abbas Ali Esmaeili in Journal of Chemical Research</p
Investigation of improved uricase release and kinetic parameters through dual affected responsive nanopolymers
No full textUricase suppresses the harmful effects of uric acid accumulation by the degradation of uric acid to allantoin. Maintaining enzyme stability is a major challenge. The stability issue can be avoided when using enzymes loaded into polymeric structures. For this purpose, uricase loaded into responsive nanopolymers (UO-RNPs) was synthesized. The characterizations such as SEM, FTIR, and zeta potential of UO-RNPs were performed. Maximum uricase loading to RNPs was investigated and the release performance of UO-RNPs also under variable conditions such as pH and temperature. On the other hand, loading yield (LY) and loading efficiency (LE) was founded 73.22 & PLUSMN; 3.62% and 71.24 & PLUSMN; 4.61%, while storage stability and reusability of the UO-RNPs were found to be about 68% and 51% of the original activity after 4 weeks and 10 cycles, respectively. From Lineweaver-Burk plot the Km was founded 0.192 and 0.327 mM for loaded and free uricase. While V max was founded 0.131 and 0.0714 & mu;M/min for free uricase and UO-RNPs, respectively. UO-RNPs showed promising matrices for high catalytic efficiency and enhanced stability. Up until now, as far as we know, the present study of the loaded uricase into responsive nanopolymers is the first attempt of uricase enzyme in such an investigation
Investitiile imateriale si performantele IMM-urilor
Full text linkAlong time, the goal of intangible assets became very important for the activity and prosperยฌity of business. This matter is achieved as well as more and more the companies operate in a global economy which has as main base the digital revolution and information management. The increase of the immaterial investments percent requires evaluation and recognition criteria by knowledge, intelligence and human competence. But recently, the accounting standards were about to accord negligible attenยฌtion or even totally ignored the appropriate modalities of report this category of assets. The accounting, obliged to bend to economic, financial and juridical logics, in a ,,Taylor" modality, presents an unreal image of the company economic life and particularly of investment activity. In a competitive environยฌment, the reliability of future economic benefits, generated by investments, depends less on their material or immaterial nature and more on the characteristics of the market they operate on. These are just a few reflections which determined us to focus our attention to this thought-provoking domain of immaterial investments, appreciated as a potential for the company.intangible assets immaterial investments competences intelligence knowledge competences potential
๊ธฐ๋ฅํ์ ์ด์ํ ํํ ํฉ์ฑ์ฝ์ด / ์ ์ฐํ์ฒ ๋๋ ธ ํ๋ธ์ด๋งค์ ๋ํ๋ฐ์ด์ค ์์ฉ
No full textFunctional magnetic nanoparticles have great importance in various fields of applications, including nanoscience, nanotechnology, environmental chemistry and biomedical applications. Although many groups have successfully described the synthesis of functional magnetic materials using various approaches and technologies, a facile, rapid, eco-friendly and economically feasible synthesis procedure that combines all the materials into a single system has remained elusive.
The shape of the synthesized nanoparticles is also an important consideration when evaluating potential practical applications. Especially for biomedical applications, the nanocube surface with specified crystal plane is expected to enhance the ability to immobilize biofunctional groups because the surface to whole volume (S/V) ratio is higher than for other shapes (e.g., octahedron, dodecahedron, icosahedron and sphere shape). Therefore, integration of cube-shaped magnetic nanoparticles (MNPs) in the form of iron oxide (Fe3O4) and, thereafter, functionalization of the surface with application-specific materials would likely enhance its performance and thus becomes a promising material for various applications.
Here I have developed, a novel one-pot sonochemical approach for the synthesis of size controlled high magnetization iron oxide nanocubes as a core in aqueous medium, without the use of surfactant. The surface of Fe3O4 nanocubes were subsequently functionalized with various inorganic materials, including silica (SiO2), titania (TiO2), carbon (C), silver (Ag) and gold (Au) and applied in several applications (including catalytic and bio-sensing applications).
Recently, two approaches (the Stober and microemulsion methods) have emerged as the major routes for the functionalization of MNP surfaces for synthesizing of core/shell nanostructures. These methods are advantageous because they produce a uniform shell with controlled thickness, however, they require complicated environmental procedures, large amounts of surfactant and long synthesis times (in the range of 6-48 h). Here I have succeeded in developing a facile, eco-friendly and time-reducing sonochemical approach for functionalization of MNPs surfaces based on the exceptional reaction conditions generated from ultrasound of high temperatures (5000 K) and pressures (~20 MPa) with high cooling rates (~1010 K/S), thus allowing the formation of many unique materials composites. Furthermore, I have also developed a modified sol-gel method for the coating of particle surfaces using only polyvinylpyrolidone (PVP) as an amphiphilic polymer. Notably, the total reaction time for the synthesis of the core/shell nanostructures was found to be shorter than the previously reported methods.
MNPs are frequently functionalized or coated with SiO2 to improve their stability, biocompatibility and functionality, giving them promise for many bio-medical applications, such as magnetic resonance imaging (MRI) contrast agents, magnetically-targeted drug delivery vehicles and agents for hyperthermia. Here I have developed a sonochemical technique as well as a modified sol-gel approach for obtaining uniform Fe3O4/SiO2 core/shell nanocubes. Furthermore, the thickness of the silica shell is easily controlled in the range of 4-18 nm by adjusting the reaction parameters. The core/shell nanocubes samples were characterized by X-ray diffractometry (XRD), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS), Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). The as-prepared Fe3O4/SiO2 core/shell nanocubes showed good stability in air for at least 4 month as well as against annealing condition of up to 300 ยฐC in presence of hydrogen gas as a strong reducing agent. Furthermore, high magnetization value of 50.7 emu/g was obtained for the sample with thin silica thickness (4 nm) as a consequence of shell thickness controlled. Moreover, the biocompatibility of the core/shell nanocube was enhanced in comparison to that of pristine Fe3O4 nanocubes. In addition, the Fe3O4/SiO2 nanocubes were functionalized by Aminopropyltriethoxysilane, and then conjugated with streptavidin-Cy3 successfully as indicated by optical fluorescence microscopy.
On the other hand, I used the developed sonochemical techniques for the functionalization of Fe3O4 nanocubes by TiO2 as well as Carbon. At first, Fe3O4/TiO2 nanocubes were successfully synthesized through hydrolysis and condensation of iron (II) sulfate heptahydrate and titanium isopropoxide (as precursors of Fe3O4 and TiO2, respectively) using single reaction sonochemical process. XRD, TEM, EDS and FTIR were used to characterize the crystal structure, size and morphology, elemental composition, metal-metal and metal-oxygen bonds of the core/shell nanocubes, respectively. The magnetic properties of the samples were measured by VSM at room temperature. Catalytic measurements on the samples showed an excellent efficiency for the degradation of methylene blue, and this efficiency was further promoted remarkably by addition of hydrogen peroxide (H2O2) within only 5 minutes of reaction time in the absence of ultraviolet irradiation. Even after recycling the sample for six times, the introduced catalyst was found to retain as much as 90% of initial efficiency. A possible reaction mechanism for the sonochemical deposition of TiO2 on the surface of Fe3O4 nanocubes and also for the degradation process of methylene blue by the introduced catalyst will be discussed in this thesis. However, PVP as an amphiphilic polymer was used as a surface linker in case of synthesizing the Fe3O4/C core/shell nanocubes.
To functionalize Fe3O4 nanocubes with noble metals such as Ag and Au nanodots, I used the sonochemical technique and the seed mediated growth method, respectively, to obtain two different structures of Fe3O4/SiO2/Ag and Fe3O4/Au nanocubes. XRD, EDS, TEM, and FTIR analyses revealed that the Fe3O4 nanocubes were successfully functionalized using these two facile methods. The resulting Fe3O4/SiO2/Ag nanocubes showed excellent catalytic efficiency toward the reduction of p-nitraoaniline to p-phenylenediamine within very short times and a recycling efficiency of 88 % for up to 15 cycles.
In addition, based on this developed sonochemical approach, I have succeeded in synthesizing different types of ferrite nanoparticles including Co-Fe2O4, NiZn-Fe2O4, and MnZn-Fe2O4. TEM results showed that different morphologies structures of spherical, cubic and mixed shapes with different particle sizes were obtained in the range of 20 to 110 nm by changing the synthesis solvent medium and compositions. I obtained high saturation magnetization value with superparamagnetic properties for the synthesized ferrite NPs samples. The obtained ferrite nanoparticles with high crystallinity, high magnetic moment, and desirable superparamagnetic properties are expected to be promising materials for various biomedical applications; and the facile aqueous approach of the sonochemical method is expected to be a promising route for the synthesis of different ferrite materials.
โ 2015 DGIST1.Introduction 1--
1.1 Iron oxide (Fe3O4) nanoparticles 2--
1.2 Motivation 4--
1.3 objective and thesis outline 8--
References 10--
2.Sonochemical method, experiments and characterizations techniques 13--
2.1 Synthesis methods of MNPs 13--
2.1.1 Sonochemistry 13--
2.1.2 Sonochemical mechanism for synthesis of Fe3O4 NPs 18--
2.1.3 Functionalization with different inorganic group 19--
2.2 Characterization of materials 19--
2.2.1 Phase determination and crystallite size measurement 19--
2.2.2 Microscopy studies (shape and size studies) 20--
2.2.3 Magnetic measurement 21--
2.2.4 Catalytic activity test 22--
2.2.5 Spectroscopic studies 23--
2.2.6 X-ray photoelectron spectroscopic studies 24--
References 24--
3.Facile sonochemical synthesis of high moment iron oxide (Fe3O4) nanocubes 26--
3.1 Introduction 26--
3.2 Experimental 29--
3.2.1 Materials 29--
3.2.2 Synthesis of iron oxide nanocubes 29--
3.2.3 Characterization 30--
3.3 Results and discussion 31--
3.3.1 Structure Characterization 31--
3.3.2 Morphology characterization 33--
3.3.3 Magnetic Properties 37--
3.4 Conclusion 42--
Refrences 43--
4.Functionalization of iron oxide (Fe3O4) nanocubes with silica (SiO2), titania (TiO2), and carbon (C) 46--
4.1 Fe3O4/SiO2 core/shell nanocubes: Novel coating approach with tunable silica thickness and enhancement in stability and biocompatibility 46--
4.1.1 Introduction 46--
4.1.2 Experimental section 49--
4.1.2.1 Materials 49--
4.1.2.2 Synthesis of hydrophilic iron oxide (Fe3O4) nanocubes 49--
4.1.2.3 Synthesis of core/shell Fe3O4/SiO2 nanocubes 49--
4.1.2.4 Streptavidin-Cy3 loading on APTES modified Fe3O4/SiO 2 Nanocube 50--
4.1.2.5 Characterization 51--
4.1.2.6 Cell viability test 52--
4.1.3 Results and discussion 52--
4.1.4 Conclusion 63--
4.2 A novel one-pot approach for synthesis of iron oxide/silica and iron oxide/carbon core/shell nanocubes 64--
4.2.1 Introductio 64--
4.2.2 Experimental 66--
4.2.2.1 Materials 66--
4.2.2.2 Synthesis of Fe3O4/SiO2 core/shell nanocubes using a sonochemicalmethod 66--
4.2.2.3 Synthesis of Fe3O4/C core/shell nanocubes using a sonochemical method 67--
4.2.2.4 Synthesis of Fe3O4/SiO2 nanocomposites without ultrasound 67--
4.2.2.5 Synthesis of Fe3O4/C nanocomposites without ultrasound 68--
4.2.2.6 Characterization 68--
4.2.3 Results and discussion 69--
4.2.4 Conclusion 79--
4.3 Fe3O4/TiO2 core/shell nanocubes: Single-batch surfactantless synthesis characterization and efficient catalysts for methylene blue degradation 80--
4.3.1 Introduction 80--
4.3.2 Experimental 82--
4.3.2.1 Materials 82--
4.3.2.2 Synthesis of Fe3O4/TiO2 core/shell nanocube 83--
4.3.2.3 Catalytic activity test 83--
4.3.2.4 Characterization 84--
4.3.3 Results and discussion 84--
4.3.3.1 Formation mechanism and morphology 84--
4.3.3.2 Structure characterization 87--
4.3.3.3 Magnetic properties 90--
4.3.3.4 Catalytic activity of the Fe3O4/TiO2 nanocubes 91--
4.3.3.4 Mechanism proposed for catalytic activity 94--
4.3.3.5 Reusability properties 95--
4.3.4 Conclusion 96--
References 97--
5.Functionalization of iron oxide (Fe3O4) nanocubes with noble metals (Ag and Au) 103--
5.1 A novel approach for the synthesis of ultrathin silica-coated iron oxide nanocubes decorated with silver nanodots (Fe3O4/SiO2/Ag) and their superior catalytic reduction of 4-nitroaniline 103--
5.1.1 Introduction 103--
5.1.2 Experimental section 106--
5.1.2.1 Materials 106--
5.1.2.2 Synthesis of iron oxide (Fe3O4) nanocubes using the sonochemical method 106--
5.1.2.3 Synthesis of the Fe3O4/SiO2 nanocubes using an ultrasonic assisted sol-gel method 107--
5.1.2.4 Synthesis of Fe3O4/SiO2/Ag nanocubes using sonochemical method 107--
5.1.2.5 Synthesis of silica (SiO2) nanoparticles using Sonochemical method 108--
5.1.2.6 Synthesis of silver decorated silica (SiO2/Ag) nanoparticles using sonochemical method 108--
5.1.2.7 Synthesis of silver (Ag) nanoparticles using sonochemical method 108--
5.1.2.8 Catalytic test 109--
5.1.2.9 Analysis methods 109--
5.1.3 Results and discussion 110--
5.1.4 Catalytic efficiency 118--
5.1.5. Conclusion 121--
5.2 A novel approach for facile synthesis of iron oxide-gold core-satellite nanocubes 122--
5.2.1 Introduction 122--
5.2.2 Experimental section 124--
5.2.2.1 Materials 124--
5.2.2.2 Synthesis of hydrophilic iron oxide (Fe3O4) nanocubes 124--
5.2.2.3 Synthesis of Fe3O4/Au core/satellite nanocubes 124--
5.2.2.4 Characterization 125--
5.2.3 Results and discussion 125--
5.2.4 Conclusion 130--
References 131--
6.Shape and size controlled synthesis of different magnetic oxide nanoparticles 136--
6.1 Introduction 136--
6. 2 Experimental section 138--
6.2.1 Materials 138--
6.2.2 Synthesis of CoFe2O4 nanoparticles 138--
6.2.3 Synthesis of NiZn-Fe2O4 nanoparticles 139--
6.2.4 Synthesis of MnZn-Fe2O4 nanoparticles 139--
6.2.5 Characterization 140--
6.3 Results and discussion. 140--
6.3.1 Shape and size controlled synthesis and characterization of CoFe2O4 NPs 140--
6.3.1.1 Structure characterization of CoFe2O4 nanoparticles 140--
6.3.1.2 Morphology characterization of CoFe2O4 nanoparticles 141--
6.3.1.3 Magnetic Properties of CoFe2O4 nanoparticles 145--
6.3.2. Synthesis and characterization of Ni Zn-Fe2O4 nanoparticles 149--
6.3.2.1 Structural characterization 149--
6.3.2.2 Morphology characterization of NiZn-Fe2O4 NPs 151--
6.3.2.3 FT-IR studies of NiZn-Fe2O4 NPs 153--
6.3.2.4 Magnetic properties of NiZn-Fe2O4 NPs 153--
6.3.3. Synthesis and characterization of MnZn-Fe2O4 nanoparticles 155--
6.3.3.1 Structure characterization of MnZn-Fe2O4 NPs 155--
6.3.3.2 Morphology characterizations of MnZn-Fe2O4 NPs 156--
6.3.3.3 Magnetic properties of Mn-Zn ferrite NPs 157--
6.4 Conclusions 159--
References 159--
Summary 163--
List of publication 168--
Acknowledgement 171--
Curriculum Vitae 172๊ธฐ๋ฅ์ฑ ์์ฑ ๋๋
ธ ์
์๋ ๋๋
ธ ๊ณผํ, ๋๋
ธ ๊ธฐ์ , ํ๊ฒฝ ํํ, ๋ฐ์ด์ค-๋ฉ๋์ปฌ ๋ฑ ์ฌ๋ฌ ๋ถ์ผ์์ ์ฃผ๋ชฉํ๊ณ ์๋ค. ์ด๋ฏธ ๋ง์ ์ฐ๊ตฌ์ค์์ ๊ธฐ๋ฅ์ฑ ๋ฌผ์ง์ ์ฌ๋ฌ ๊ฐ์ง ํฉ์ฑ ๋ฐฉ๋ฒ๊ณผ ๊ธฐ์ ์ ๋ํด ๋ค๋ฃจ์์ง๋ง ์ฌ์ ํ ์ฝ๊ณ ๋น ๋ฅด๋ฉฐ ๊ฒฝ์ ์ ์ผ๋ก ์คํ ๊ฐ๋ฅํ ํฉ์ฑ ๋ฐฉ๋ฒ์ ๋ํด ํ๋ฐํ ์ฐ๊ตฌ๊ฐ ์งํ๋๊ณ ์๋ค.
์์ฑ ๋๋
ธ ์
์์ ํํ๋ ์ฌ๋ฌ ๋ถ์ผ์ ์ดํ๋ฆฌ์ผ์ด์
์ ์์ด ์์ฑ ๋๋
ธ ์
์์ ํน์ฑ ํ๊ฐ์ ๋ํ ์ค์ํ ์งํ๋ก ์ฌ์ฉ๋๋ค. ํนํ, ์์ ๋งํ๋ ๋ฐ์ด์ค-๋ฉ๋์ปฌ ์ดํ๋ฆฌ์ผ์ด์
์์๋ 6๋ฉด์ฒด ํํ์ ๋๋
ธ ์
์๊ฐ ๋ฐ์ด์ค๊ธฐ๋ฅ์ฑ ๋ฌผ์ง์ ๊ฒฐํฉ์ ๋ํ ๋ฉด์ ํจ์จ์ ๋์ด๊ธฐ ์ํ ๊ฐ์ฅ ์ ํฉํ ๊ตฌ์กฐ์ด๋ค. 6๋ฉด์ฒด ๋๋
ธ ์
์๊ฐ 8๋ฉด์ฒด, 12๋ฉด์ฒด, 20๋ฉด์ฒด ๋๋ ๊ตฌ ํํ์ ๋๋
ธ ์
์์์๋ณด๋ค ์ ์ฒด ๋ถํผ์ ๋ํ ํ๋ฉด์ ๋น๊ฐ ๋๊ธฐ ๋๋ฌธ์ด๋ค. ๊ทธ๋์ ์์ฑ ๋๋
ธ ์
์์ 6๋ฉด์ฒด ์ ์๊ณผ ํ๋ฉด ๊ธฐ๋ฅํ๋ ๋๋
ธ ์
์์ ์ฑ๋ฅ ํฅ์๊ณผ ์์ผ๋ก์ ์์ฉ์ ์์ด ๋งค์ฐ ์ค์ํ ๊ธฐ์ ์ด ๋ ๊ฒ์ด๋ค.
์ฐ์ , ์ ์ผํ๊ฒ ์์ฑ ์ฉ๋งค์์ ํฉ์ฑํ ์ ์๊ณ , ์ฌ์ด์ฆ๋ฅผ ์กฐ์ ์ด ๊ฐ๋ฅํ Sonochemical ํฉ์ฑ ๋ฐฉ๋ฒ์ผ๋ก ๋์ ์ํ ํน์ฑ์ ๊ฐ๋ 6๋ฉด์ฒด์ FeโOโ๋ฅผ ํฉ์ฑํ์๋ค. ๊ทธ๋ฆฌ๊ณ ๋ฐ์ด์ค ์ผ์ฑ, ์ด๋งค ๋ฑ ์์ผ๋ก์ ์์ฉ๋จ๊ณ๋ฅผ ์ํด Silica (SiOโ), Titania (TiOโ), ํ์ (C), ์ (Ag), ๊ธ (Au) ๋ฑ์ ๋ค์ํ ์ฌ๋ฃ๋ค๋ก 6๋ฉด์ฒด์ FeโOโ ์์ฑ ๋๋
ธ ์
์๋ฅผ ํ๋ฉด ์ฒ๋ฆฌํ์๋ค.
์ต๊ทผ, ์์ฑ ๋๋
ธ ์
์์ ํ๋ฉด ์ฒ๋ฆฌ๋ ์ผ๋ฐ์ ์ผ๋ก Stober ๋ฐฉ๋ฒ๊ณผ Microemulsion ๋ฐฉ๋ฒ์ด ์ฃผ๋ก ์ฌ์ฉ๋๊ณ ์๋ค. ์ด๋ฌํ ๋ฐฉ๋ฒ๋ค์ core/shell ๊ตฌ์กฐ์ ํฉ์ฑ์ด ๊ฐ๋ฅํ๊ณ Shell์ ๋๊ป ์กฐ์ ์ ๊ท ์ผํ๊ฒ ํฉ์ฑํ ์ ์๋ค๋ ์ด์ ์ด ์์ง๋ง, ๋ง์ ์์ ๊ณ๋ฉดํ์ฑ์ ์ฌ์ฉ, 6 ~ 48 ์๊ฐ์ ๊ธด ๋ฐ์ ์๊ฐ ๋ฑ์ ๋ฌธ์ ์ ์ ๊ฐ์ง๊ณ ์๋ค. ์ด ์คํ์์๋ Sonochemical ํฉ์ฑ ๋ฐฉ๋ฒ์ผ๋ก ๋์ ์จ๋ (5000 K), ์๋ ฅ (~20 MPa), ๋น ๋ฅธ ๋๊ฐ ์๋ (~10ยนโฐ K/S) ๋ฑ์ ๋ฐ์ ์กฐ๊ฑด์ ์กฐ์ ํ์ฌ ์ด๋ฌํ ๋ฌธ์ ์ ์ ๊ฐ์ ํ์๊ณ , ๊ทธ๋ก ์ธํด ์ ์ฒด ํฉ์ฑ ๋ฐ ์ฝํ
๊ณต์ ์๊ฐ์ด ๊ธฐ์กด ๋ฐ์ ์๊ฐ์ ๋นํด ๋งค์ฐ ๋จ์ถ๋์๋ค. ๋ํ, ์์ชฝ ์น๋งค์ฑ ๊ณ ๋ถ์์ธ PVP (polyvinylpyrrolidone)๋ฅผ ์ฝํ
ํ๊ธฐ ์ํ Sol-gel ๋ฐฉ๋ฒ๋ ์ฐ๊ตฌํ์๋ค.
Silica (SiOโ) ์ฝํ
๋ ์์ฑ ๋๋
ธ ์
์๋ MRI ์กฐ์์ , Drug delivery, Hyperthermia ๋ฑ์ ๋ฐ์ด์ค ๋ฉ๋์ปฌ ์ดํ๋ฆฌ์ผ์ด์
์ ์์ด ์์ ์ฑ, ์์ฒด ์ ํฉ์ฑ, ๊ธฐ๋ฅ์ฑ์ด ์ฐ์ํ๋ค. ์์ผ๋ก์ ์ด๋ฌํ ์์ฉ์ ์ํด์ Sonochemical ํฉ์ฑ ๋ฐฉ๋ฒ๊ณผ Sol-gel ์ฝํ
๋ฐฉ๋ฒ์ผ๋ก FeโOโ/SiOโ core/shell์ ์์ฑ ๋๋
ธ ์
์ ๋ง๋๋ ๋ฐฉ๋ฒ์ ์ฐ๊ตฌํ์๋ค. ๋ฐ์ ์กฐ๊ฑด์ ๋ฌ๋ฆฌํจ์ผ๋ก์จ Silica shell์ ๋๊ป๋ฅผ 4โ18 nm์ ๋ฒ์ ๋ด์์ ์กฐ์ ์ด ๊ฐ๋ฅํ๋ค. (XRD), (TEM), (EDS), (FT-IR), (VSM) ์ฅ๋น๋ก FeโOโ/SiOโ core/shell ํํ์ 6๋ฉด์ฒด ์์ฑ ๋๋
ธ ์
์์ ํน์ฑ์ ๋ถ์ํ์๋ค. FeโOโ/SiOโ core/shell์ ์์ฑ ๋๋
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์๋ ๊ณต๊ธฐ ์ค ๋
ธ์ถ์๋ ์ต์ 4 ๊ฐ์ ๋์ ์์ ์ฑ์ ์ ์งํ์๊ณ , ๊ฐํ ํ์์ ์ธ Hโ ๊ธฐ์ฒด๊ฐ ์กด์ฌํ๋ 300 โ ๊ฐ์ด ์กฐ๊ฑด์์๋ ์์ ์ฑ์ ์ ์งํ์๋ค. ๋ํ, 4nm์ ๋๊ป๋ก silica ์ฝํ
๋ ์์ฑ ๋๋
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์๋ 50.7 emu/g ์ ๋์ ๋์ ์ํ๊ฐ์ ๊ฐ์ก๋ค. ์์ฒด ์ ํฉ์ฑ๋ FeโOโ ๋๋
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์์ ๋นํดcore/shell silica ์ฝํ
๋ ์์ฑ ๋๋
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์๊ฐ ํจ์ฌ ์ฐ์ํ์๋ค. ๋ํ Aminopropyltriethoxysilane์ผ๋ก ์ฝํ
๋ FeโOโ/SiOโ ์์ฑ ๋๋
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์์ streptavidin-Cy3๊ฐ ๊ฒฐํฉ๋์ด ์๋ ๊ฒ์ Optical fluorescence microscopy๋ก ํ์ธํ์๋ค.
Sonochemical ํฉ์ฑ ๋ฐฉ๋ฒ์ผ๋ก ํ์ (C)์ Titania (TiOโ)๋ฅผ ์ฌ์ฉํ์ฌ ์์ฑ ๋๋
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์์ ํ๋ฉด์ฒ๋ฆฌ๋ฅผ ํด๋ณด์๋ค. Titanium isopropoxide์ iron(โ
ก) sulfate heptahydrate๊ฐ ๊ฐ์๋ถํด์ ์์ถ ํ์์ ๊ฑฐ์น๋ฉฐ ๋ฌด์ ํ Titania๋ก ์ฝํ
๋ FeโOโ ์์ฑ ๋๋
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์๊ฐ ํฉ์ฑ๋์๋ค. (XRD), (TEM), (EDS), (FT-IR)๋ฅผ ์ฌ์ฉํ์ฌ FeโOโ/TiOโ core/shell ์์ฑ ๋๋
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์์ ๊ฒฐ์ ๊ตฌ์กฐ, ํฌ๊ธฐ, ํํ, ์ฑ๋ถ ๋ถ์, ๊ธ์-๊ธ์ ๊ฒฐํฉ, ๊ธ์-์ฐ์ ๊ฒฐํฉ์ ํ์ธํ์๊ณ , (VSM)์ผ๋ก ์์จ์์์ ์์ฑ ๋๋
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์์ ์๊ธฐ์ ํน์ฑ์ ์ธก์ ํ์๋ค. ๋ํ, FeโOโ/TiOโ๋ฅผ ์ด๋งค๋ก ์ฌ์ฉํ methlyene blue ๋ถํด ๋ฐ์์์ ์ข์ ํจ์จ์ ๋ณด์์ผ๋ฉฐ hydrogen peroxide (H2O2) ์กฐ๊ฑด์์๋ ์์ธ์ ์กฐ์ฌ ์์ด๋ 5๋ถ ์ด๋ด์ ๋ฐ์์ ํ์ฌ ๋ ๋์ ํจ์จ์ฑ์ ๋ณด์ฌ์ฃผ์๋ค. 6๋ฒ์ ์ฌ์ฌ์ฉ ํ์๋ ์ด๊ธฐ ํจ์จ์ 90% ๊ฐ๋์ ํจ์จ์ ์ ์งํ์๋ค. Titania์ Sonochemical deposition์ ๋ํ ๋ฐ์ ๋ฉ์ปค๋์ฆ๊ณผ Methylene blue์์์ ๋ถํด ์ด๋งค ๋ฐ์ ๋ฉ์ปค๋์ฆ์ ๋ค์์ ๋
ผ์ํ ์์ ์ด๋ค. ์์ชฝ ์น๋งค์ฑ ๊ณ ๋ถ์์ธ PVP (polyvinylpyrrolidone)๋ Fe3O4/C core/shell ์์ฑ ๋๋
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์ ํฉ์ฑ์์ ๋ ๋ฌผ์ง์ ์ฐ๊ฒฐํด์ฃผ๋ ์ญํ ์ ํด์ฃผ์๋ค. Au ๋๋ Ag nanodot์ผ๋ก ์ฝํ
๋ Fe3O4/SiO2/Ag and Fe3O4/Au ๊ตฌ์กฐ์ nanocube๋ฅผ ํฉ์ฑํ๊ธฐ ์ํด Sonochemical method์ Seed mediated growth method๋ฅผ ์ฌ์ฉํ์๋ค. XRD, EDS, TEM, FT-IR ๋ถ์ ์ฅ๋น๋ฅผ ํตํด ๋ method๋ก nano-dot ์ฝํ
๋ Fe3O4์ ํน์ฑ์ ํ์ธํ์๋ค. Fe3O4/SiO2/Ag ์์ฑ ๋๋
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์๋ p-Nitraoaniline์ p-Phenylenediamine๋ก ํ์์ํค๋ ๋ฐ์์์ 15 ํ ์ฌ์ฉ์์๋ 88%์ ํจ์จ์ ๋ณด์ด๋ ์ฐ์ํ ์ด๋งค๋ก์์ ์ญํ ์ ํ์๋ค.
Sonochemical ํฉ์ฑ ๋ฐฉ๋ฒ์ ๊ธฐ๋ฐ์ผ๋ก Co-Fe2O4, NiZn-Fe2O4, MnZn-Fe2O4 ์ ๊ฐ์ ์ฌ๋ฌ ์ข
๋ฅ์ ์ฐํ์ฒ ๋๋
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์๋ฅผ ํฉ์ฑํด๋ณด์๋ค. ํฉ์ฑ ์ฉ๋งค์ ๋ฐ๋ผ 6๋ฉด์ฒด, ๊ตฌ ํํ ๋ฑ ๋ค์ํ ๋๋
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์์ ํํ์ 20~110 nm ๋ฒ์ ๋ด์์ ์ฌ์ด์ฆ ์กฐ์ ์ด ๊ฐ๋ฅํจ์ TEM์ ํตํด ๊ด์ธกํ ์ ์์๋ค. ๋ํ ์ด๋ ๊ฒ ํฉ์ฑ๋ ๋๋
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์๋ ๋์ ์ํ๊ฐ์ ๊ฐ์ง๊ณ ์ด์์์ฑ ํน์ฑ์ ๊ฐ๋๋ค. Sonochemical ํฉ์ฑ ๋ฐฉ๋ฒ์ ๋ค์ํ ์ฐํ์ฒ ๋๋
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์ ํฉ์ฑ์ ์์ด ์์ฑ ์ฉ๋งค๋ก ํ๋ ๋งค์ฐ ์ฉ์ดํ ํฉ์ฑ๋ฒ์ด๋ผ ํ ์ ์๊ณ , ๊ณ ๊ฒฐ์ ์ฑ, ์ด์์์ฑ, ๊ณ ์ํ์จ ํน์ฑ์ ๊ฐ๋ ์ฐํ์ฒ ๋๋
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์๋ ์์ผ๋ก์ ํญ๋์ ๋ฐ์ด์ค ์์ฉ์ ์์ด ์ ๋ ์ ๋งํ ๋ฌผ์ง์ด๋ผ๊ณ ํ ์ ์๋ค.
โ 2015 DGISTPh. D.dCollectio
Novel hybrid compounds containing 1,2,3-triazole and naphthalene subunits as xanthine oxidase inhibitors
No full textIn the present study, some hybrid compounds containing 1,2,3-triazole and naphthalene subunits 16(a-g) and 17(a-f) were synthesized and characterized by 1H, 13C-NMR, FT-IR, and HR-MS analyses. The in vitro inhibitor activities on the xanthine oxidase (XO) enzyme of all the target compounds were investigated and compared with allopurinol, which is one of the most common gout drugs and inhibits the XO. The activity results show that all the target compounds have potential XO inhibitor activities. The compounds showed IC50 values in the range of 0.825-2.254 mu M on the XO. IC50 value of allopurinol on the XO was determined to be 1.475 mu M. 16e and 17e compounds among them exhibited the best inhibitions compared to other compounds and allopurinol. Additionally, molecular docking studies were carried out on the 3D crystallographic structure of the XO to investigate possible interactions with the active site of the XO of all compounds. According to the docking results, all the target compounds showed that the best binding energies vary in the between - 9.71 kcal.mol-1 and - 11.43 kcal.mol-1. Finally, in silico ADME and toxicity properties of the compounds were investigated using the Swiss ADME, ProTox-II, and Osiris Property Explorer websites and it has been predicted that the target compounds have low toxicity profiles. Consequently, the compounds can be considered new promising inhibitors for the XO
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