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Abstrak :
Two-dimensional photonic crystal structures not only confine light and guide waves laterally but also reflect light in the normal direction due to a slow Bloch mode effect. However, evidence of the utilization of this structure as a mirror is required. Therefore, in this work, a simulation was made and experimental results were obtained to prove that there was an increase in the intensity of reflected CdSe colloidal quantum dots emission in the normal direction when a 2D photonic crystal structure was used. A thin TiO2 film was shaped into a two-dimensional photonic crystal structure using a simple sol-gel and polystyrene-mask-etching procedure. This structure was then placed on top of the thin CdSe quantum dots film layer. The emission of quantum dots onto the two-dimensional photonic crystal structure was compared to quantum dots emission onto a flat, thin TiO2 film. An increase in the quantum dots emission of up to 105% was in the presence of the two-dimensional photonic crystal structure. This finding is very useful for photonic device applications, such as light-emitting diodes, laser systems and bio-tagging detection systems.

Studi Simulasi dan Eksperimen Struktur Kristal Fotonik Dua Dimensi sebagai Pemantul Emisi Kuantum Dot Masalah Arah Normal. Kristal fotonika dua dimensi tidak hanya dapat mengukung cahaya dan memandu gelombang ke arah sisi horizontal, tapi juga mampu memantulkan cahaya ke arah normal dikarenakan efek moda slow Bloch . Namun bukti tentang penggunaan stuktur ini masih dibutuhkan. Untuk itu dalam penelitian ini hasil simulasi dan percobaan telah didapatkan untuk membuktikan bahwa terjadi peningkatan pantulan emisi CdSe kuantum dot colloid pada arah normal saat kristal fotonika dua dimensi digunakan. Sebuah lapisan tipis TiO2 dibentuk menjadi kristal fotonika dua dimensi denga menggunakan teknik sol-gel yang sederhana dan etching dengan menggunakan polystyrene. Struktur ini diletakkan di atas lapisan kuantum dot CdSe. Emisi dari kuantum dot di atas kristal fotonika dua dimensi dibandingkan dengan emisi kuantum dot di atas lapisan tipis dan datar TiO2. Peningkatan emisi kuantum dot hingga mencapai 105% berkat kehadiran kristal fotonika dua dimensi. Hasil ini sangat berguna untuk aplikasi divais fotonika seperti LED, sistem laser dan sisten detesi bio-tagging.

Abstrak :
This book highlights the theoretical foundations of and experimental techniques in photothermal heating and applications involving nanoscale heat generation using gold nanostructures embedded in various media. The experimental techniques presented involve a combination of nanothermometers doped with rare-earth atoms, plasmonic heaters and near-field microscopy. The theoretical foundations are based on the Maxwell’s and heat diffusion equations. In particular, the working principle and application of AlGaN:Er3+ film, Er2O3 nanoparticles and β-NaYF4:Yb3+,Er3+ nanocrystals for nanothermometry based on Er3+ emission are discussed. The relationship between superheated liquid and bubble formation for optically excited nanostructures and the effects of the surrounding medium and solution properties on light absorption and scattering are presented. The application of Er2O3 and β-NaYF4:Yb3+,Er3+ nanocrystals to study the temperature of optically heated gold nanoparticles is also presented. In closing, the book presents a new thermal imaging technique combining near-field microscopy and Er3+ photoluminescence spectroscopy to monitor the photothermal heating and steady-state sub-diffraction local temperature of optically excited gold nanostructures.

Abstrak :
Dari segi komposisi kimianya, propolis merupakan produk yang sangat beragam. Asam fenolik, asam benzoat, asam sinamat, dan flavonoid adalah senyawa biologis aktif yang paling penting. Propolis juga menampilkan sifat anti-inflamasi pada proses peradangan akut dan kronis, dan hal ini disebabkan oleh kandungan senyawa polifenolnya yang tinggi. Pada penelitian ini, hydrogel berfungsi sebagai matriks ekstra seluler semi sintetik atau sintetik yang memiliki kapasitas untuk membawa obat molekul kecil dan/atau protein, faktor pertumbuhan, dan komponen lain yang akan dilepas dan dianalisis profil pelepasannya. Carbon Quantum Dots (CQD) adalah nanopartikel kuasi-bulat photoluminescence yang diskrit (dengan diameter kurang dari 10 nm) sehingga muncul sebagai bahan yang disukai dan layak di bidang biomedis (seperti biosensing, pengiriman biomolekul/obat, dan bioimaging). Tantangan utama dalam pengaplikasian hydrogel untuk pelepasan kandungan obat dalam kasus ini adalah profil pelepasan obat dari matriks hydrogel yang relatif sulit untuk dikontrol. Maka, peran Carbon Quantum Dots sebagai agen biosensor dapat membantu dalam mengatasi tantangan tersebut. Integrasi CQD dalam matriks hydrogel berperan dalam pelepasan kandungan propolis ke medium dengan hasil sampel hydrogel-CQD-propolis varian B (kandungan larutan CQD 40%) memiliki profil pelepasan propolis yang paling optimal dengan 80% kandungan total propolis berhasil terlepas setelah 72 jam pelaksanaan uji pelepasan. Sedangkan intensitas photoluminescence tertinggi juga ditemukan pada sampel B dengan puncak berada pada panjang gelombang 525 nm, yaitu senilai 7700 a.u. Akan tetapi, ditemukan juga indikasi kegagalan cross-linking antara kandungan chitosan dan glutaraldehyde berdasarkan analisis gugus fungsi dengan FTIR spectroscopy dalam matriks hydrogel yang menyebabkan kekuatan mekanis hydrogel menjadi kurang optimal. ......In terms of chemical composition, propolis is a very diverse product. Phenolic acid, benzoic acid, cinnamic acid and flavonoids are the most important biologically active compounds. Propolis also displays anti-inflammatory properties in acute and chronic inflammatory processes, and this is due to its high content of polyphenolic compounds. In this cellular study, the hydrogel functions as a semi-synthetic or synthetic extra matrix that has the capacity to carry small molecule drugs and/or proteins, growth factors, and other components which will be released and analyzed for their solvent profiles. Carbon Quantum Dots (CQD) are discrete photoluminescence quasi-spherical nanoparticles (less than 10 nm in diameter) that are emerging as preferred and viable materials in biomedical fields (such as biosensing, biomolecule/drug delivery, and bioimaging). The main challenge in applying hydrogels in the field of drug release is the difficulty in controlling the drug release profile. Therefore, the role of Carbon Quantum Dots as a biosensor agent can help overcome this challenge. The integration of CQD in the hydrogel matrix played a role in retaining the propolis content into the medium with the result that the hydrogel-CQD-propolis variant B (40% CQD solution content) had the most optimal propolis withdrawal profile with 80% of total propolis being released after 72 hours of the trial. Meanwhile, the highest photoluminescence intensity was also found in sample B with a peak at a wavelength of 525 nm, which is 7700 a.u. However, there were also indications of cross-linking failure between chitosan and glutaraldehyde content based on functional group analysis using FTIR spectroscopy in the hydrogel matrix which reduces the hydrogel mechanical strength.

Abstrak :
This book highlights the theoretical foundations of and experimental techniques in photothermal heating and applications involving nanoscale heat generation using gold nanostructures embedded in various media. The experimental techniques presented involve a combination of nanothermometers doped with rare-earth atoms, plasmonic heaters and near-field microscopy. The theoretical foundations are based on the Maxwells and heat diffusion equations. In particular, the working principle and application of AlGaN:Er3+ film, Er2O3 nanoparticles and β-NaYF4:Yb3+,Er3+ nanocrystals for nanothermometry based on Er3+ emission are discussed. The relationship between superheated liquid and bubble formation for optically excited nanostructures and the effects of the surrounding medium and solution properties on light absorption and scattering are presented. The application of Er2O3 and β-NaYF4:Yb3+,Er3+ nanocrystals to study the temperature of optically heated gold nanoparticles is also presented. In closing, the book presents a new thermal imaging technique combining near-field microscopy and Er3+ photoluminescence spectroscopy to monitor the photothermal heating and steady-state sub-diffraction local temperature of optically excited gold nanostructures.