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"ABSTRAKTelah berhasil disintesis dan dipelajari material karbon nanopori yang diperoleh dari interaksi antara padatan silikon karbida dan HCl menggunakan metode variasi ultrasonik dan pemanasan. Silion karbida dengan kemurnian lebih dari 98% dari Aldrich digunakan sebagai sumber karbon, sedangkan larutan HCl berfungsi sebagai sumber gas klor yang akan bereaksi dan mengambil silikon (Si) dari silikon karbida. Dalam penelitian ini diadakan lima variasi yang berbeda yaitu disebut sebagai CDC1, CDC2, CDC3, CDC4 dan CDC5. Metode ultrasonik dan pemanasan terhadap material CDC1, CDC2, CDC3, CDC4, CDC5 didapatkan stabil pada suhu pemanasan 1000 o C dengan perbandingan berat wt% antara silikon karbida dan pori karbon hasil sintesis adalah CDC1 wt% = SiC : C = 75% : 25%, CDC2 wt% = SiC : C = 35% : 65%, CDC3 wt% = SiC : C = 34,5% : 65,5%, CDC4 wt% = SiC : C = 30% : 70% dan CDC5 wt% = SiC : C = 25% : 75%. Pembentukan pori dan pertumbuhan kristal hanya muncul setelah proses pemanasan. Material CDC1, CDC2, CDC3, CDC4, CDC5 hasil sintesis masing-masing memiliki struktur heksagonal dengan grup ruang P6 3 mc dan parameter kisi berturut-turut yaitu a = b = 2,456 Å dan c = 12,350 Å. Pembuktian berdasarkan analisis GSAS refine Fourier memperlihatkan bahwa material CDC1, CDC2, CDC3, CDC4, CDC5 memiliki struktur rentang panjang arah sumbu c untuk CDC1 = 15Å, CDC2 = 15Å, CDC3 = 20Å, CDC4 = 30Å, CDC5 = 35Å terhadap pemanjangan parameter kisi c masing -masing CDC1 = 12,35Å, CDC2 = 15,1Å, CDC3 = 18Å, CDC4 = 20,4Å dan CDC5 = 24,1Å dan mengalami penurunan nilai densitas CDC1= 3 gr/cm 3 , CDC2 = 2,45 gr/cm 3 , CDC3 = 1,5 gr/cm 3 , CDC4 = 1,4 gr/cm 3 dan CDC5 = 1,2 gr/cm 3 . Struktur karbon m akropori - nanopori rentang panjang heksagonal tipe pori silinder memiliki ukuran pori 200 nm - 35 nm, luas permukaan 55 m 2 /gram-1250 m 2 /gram dan sangat khas muncul pada bilangan gelombang 1095, 57 cm -1 dan karenanya material tersebut diharapkan dapat digunakan sebagai media penyimpan gas.

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ABSTRACTNanopores carbide derived carbon synthesized from silicon carbide and HCl by using ultrasonic and sintering at high temperature has been investigated. Silicon carbide with a purity better than 98% from Aldrich was used as a carbon source while HCl was used as a leaching agent.. In this investigation, five different processes were carried out, i.e. CDC1, CDC2, CDC3, CDC4 and CDC5. Ultrasonik process and sintering on these five CDC1, CDC2, CDC3, CDC4 and CDC5 materials were found to be stable at 1000 o C with the weight ratio between silicon carbide and the derived carbon CDC1 wt% = SiC : C = 75% : 25%, CDC2 wt% = SiC : C = 35% : 65%, CDC3 wt% = SiC : C = 34,5% : 65,5%, CDC4 wt% = SiC : C = 30% : 70% dan CDC5 wt% = SiC : C = 25% : 75%. Pores formation and crystal growth occur after sintering process. Each derived carbon material has the hexagonal structure and a space group of P6 3 mc and lattice parameters a = b = 2.456 Å and c = 12.350 Å. Fourier analysis by using a package program of GSAS showed that CDC1, CDC2, CDC3, CDC4 and CDC5 have an expansion on the c direction in which CDC1 = 15 Å, CDC2 = 15 Å, CDC3 = 20 Å, CDC4 = 30 Å, and CDC5 = 35 Å from the original values of CDC1 = 12.35 Å, CDC2 = 15. 1 Å, CDC3 = 18 Å, CDC4 = 20. 4 Å and CDC5 = 24.1 Å. Furthermore, the elektronic density was found to be CDC1= 3 gr/cm 3 , CDC2 = 2.45 gr/cm 3 , CDC3 = 1.5 gr/cm 3 , CDC4 = 1.4 gr/cm 3 and CDC5 = 1.2 gr/cm 3 . The long hexagonal ribbon of the derived carbon has the size of 200 nm ? 35 nm, surface area of 55 m 2 /g ? 1250 m 2 /g and occur at a wave number of 1095. 57 cm -1 . This material has the potential application as a gas storage."

"Krisis air bersih masih menjadi permasalahan di berbagai belahan bumi. Oleh karena itu, diperlukan teknologi destilasi air yang mudah dibuat, digunakan, dan terjangkau. Sistem evaporasi fototermal hadir sebagai solusi dalam mengatasi krisis air, dengan menggunakan energi terbarukan yaitu matahari. Logam transisi decalchogenides (TMD) menjadi bahan yang banyak digunakan sebagai material fototermal, seperti molybdenum disulfide (MoS2) dan molydenum trioxide dengan fase orthorombik (α-MoO3) yang telah terbukti memiliki kinerja yang baik. Dalam penelitian ini, kami mengusulkan material CC-MoO3 dengan pengunaan fase lain MoO3 yaitu fase hexagonal (h-MoO3) dan fase transisi hexagonal-orthorombik. Penumbuhan MoO3 dilakukan dengan metode hidrotermal pada subtrat carbon cloth (CC) yang memiliki desain 3D dan berpori, sehingga MoO3 dapat tumbuh pada setiap serat dan desain berpori ini memudahkan transportasi. Durasi sintesis dilakukan selama 6, 9, dan 12 jam pada suhu 130⁰C. Hasil pengujian kinerja sistem evaporasi fototermal menunjukkan bahwa sampel CC-MoO3 6 jam memiliki kinerja terbaik, dengan laju evaporasi 1,59 kg/m2h dan efisiensi energinya sebesar 98,93% dibawah pencayahan 1 sun. Akhirnya, pengurangan durasi sintesis dapat meningkat kinerja MoO3 sebagai material fototermal dengan memanfaatkan ukuran partikel microrods yang besar sehingga terbentuk jalur uap yang efektif untuk memperoleh air bersih. Disisi lain, penambahan durasi sintesis yang bertambah menyebabkan fase orthorombik menutupi jalur mikro pada CC-MoO3 yang mengurangi kinerja evaporasi.

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The clean water crisis continues to be a problem in various parts of the world. Therefore, the development of easy-to-make, user-friendly, and affordable water distillation technology is necessary. Photothermal evaporation systems have emerged as a solution to address the water crisis by harnessing renewable energy from the sun. Transition metal dichalcogenides (TMDs), such as molybdenum disulfide (MoS2) and molybdenum trioxide with an orthorhombic phase (α-MoO3), have been widely used as photothermal materials due to their proven performance. In this study, we propose the development of CC-MoO3 material, utilizing alternative phases of MoO3, namely the hexagonal phase (h- MoO3) and the hexagonal-orthorhombic transition phase. The growth of MoO3 was conducted through hydrothermal synthesis on a 3D porous carbon cloth (CC) substrate, allowing MoO3 to grow on each fiber and facilitating transport. The synthesis duration was set at 6, 9, and 12 hours at a temperature of 130⁰C. The performance testing of the photothermal evaporation system revealed that the CC-MoO3 sample synthesized for 6 hours exhibited the best performance. It achieved an evaporation rate of 1.59 kg/m2h and an energy efficiency of 98.93% under 1 sun illumination. Reducing the synthesis duration improved the performance of MoO3 as a photothermal material by utilizing larger microrod particle sizes, which facilitated the formation of an effective vapor path for obtaining clean water. On the other hand, increasing the synthesis duration resulted in the orthorhombic phase covering the microchannels of CC-MoO3, which adversely affected the evaporation performance."

"Offering a well-balanced blend of theory and hands-on applications, this book presents a unified framework for the main dissipative phenomena in metallic materials: plasticity and damage. Based on representation theory for tensor functions and scale-bridging theorems, this framework enables the development of constitutive models that account for the influence of crystallographic structures and deformation mechanisms on the macroscopic behavior. It allows readers to develop a clear understanding of the range of applicability of any given model, as well as its capabilities and limitations, and provides procedures for parameter identification along with key concepts necessary to solve boundary value problems, making it useful to both researchers and engineering practitioners. Although the book focuses on new contributions to modeling anisotropic materials, the review of the foundations of plasticity and models for isotropic materials, completed with detailed mathematical proofs mean that it is self-consistent and accessible to graduate students in engineering mechanics and material sciences."