Perancangan Dan Pembuatan Aplikasi Ecommerce Pada Toko Agung Jaya

Perkembangan teknologi pada saat ini telah berkembang secara pesat. Dimana hampir semua kegiatan dapat dilakukan pada dunia maya, misalnya melakukan transaksi pembayaran, pembelian barang, pemesanan tiket, baik tiket pesawat maupun tiket kereta api, dan lainnya.Di jaman sekarang ini penjualan secara online sudah banyak. Hal ini dikarenakan untuk membuka suatu USAha online lebih mudah dan murah dari pada membuka USAha disuatu tempat yang berbentuk bangunan. Selain itu, dengan cara berjualan online orang akan lebih banyak mengetahui barang apa saja yang dijual, karena semua orang dapat melihat tanpa harus mendatangi tempat itu.Berdasarkan hasil pengujian aplikasi yang telah dibuat, aplikasi dapat menampilkan data barang yang dijual beserta promo yang ditawarkan. Selain itu aplikasi ini mempunyai fitur konfirmasi account untuk mengaktifkan account dan kirim detail order

学会抄録

<p><b>Observation of pulmonary artery sections</b> (200X, HE) The pulmonary artery wall thickness of disease (D) is noticeably increased. In the D sample, 1) the tunica adventicia was more compact and exhibited increased connective tissue; 2) the smooth muscle fiber was thicker; 3) there was excessive fiber production; and 4) the intima was more compact. The arrows indicate the pathological changes.</p

Salmonella ubiquitination: ARIH1 enters the fray.

© 2017 EMBO. Ubiquitination is a post-translational modification in which ubiquitin, a 76-amino acid polypeptide, is covalently bound to one or more lysines of a target protein. Ubiquitination is mediated by the coordinated activity of ubiquitin activating (E1), conjugating (E2), and ligating (E3) enzymes. Ubiquitin is widely investigated for its ability to regulate key biological processes in the cell, including protein degradation and host-bacteria interactions. The determinants underlying bacterial ubiquitination, and their precise roles in host defense, have not been fully resolved. In this issue of EMBO Reports, Polajnar et al discover that Ring-between-Ring (RBR) E3 ligase ARIH1 (also known as HHARI) is involved in formation of the ubiquitin coat surrounding cytosolic Salmonella. Evidence suggests that ARIH1, in cooperation with E3 ligases LRSAM1 and HOIP, modulates the recognition of intracellular bacteria for cell-autonomous immunity

Mechanistic Study of Methanol Synthesis from CO₂ and H₂ on a Modified Model Mo₆S₈ Cluster

We report the methanol synthesis from CO₂ and H₂ on metal (M = K, Ti, Co, Rh, Ni, and Cu)-modified model Mo₆S₈ catalyst using density functional theory (DFT). The results show that the catalytic behavior of a Mo₆S₈ cluster is changed significantly due to the modifiers, via the electron transfer from M to Mo₆S₈ and therefore the reduction of the Mo cation (ligand effect) and the direct participation of M in the reaction (ensemble effect) to promote some elementary steps. With the most positively charged modifier, the ligand effect in the case of K–Mo₆S₈ is the most obvious among the systems studied; however, it cannot compete with the ensemble effect, which plays a dominate role in determining activity via the electrostatic attraction in particular to stabilize the CH_<i>x</i>O_<i>y</i> species adsorbed at the Mo sites of Mo₆S₈. In comparison, the ligand effect is weaker and the ensemble effect is more important when the other modifiers are used. In addition, the modifiers also vary the optimal reaction pathway for methanol synthesis on Mo₆S₈, ranging from the reverse water–gas shift (RWGS) + CO hydrogenation as that of Mo₆S₈ to the formate pathway. Finally, K is able to accelerate the methanol synthesis on Mo₆S₈ the most, whereas the promotion by Rh is relatively small. Using the modifiers like Ti, Co, Ni, and Cu, the activity of Mo₆S₈ is decreased instead. The relative stability between *HCOO and *HOCO is identified as a descriptor to capture the variation in mechanism and scales well with the estimated activity. Our study not only provides better understanding of the reaction mechanism and actives on the modified Mo₆S₈ but also predicts some possible candidates, which can be used as a promoter to facilitate the CH₃OH synthesis on Mo sulfides

High Seebeck Coefficient Electrochemical Thermocells for Efficient Waste Heat Recovery

An electrochemical thermocell realizes thermal to electric energy conversion when two electrodes operate the same reversible reaction but at different temperatures. Its Seebeck coefficient is determined by the entropy change of the redox reaction. Here we report a thermocell containing acetone and iso-propanol as the redox couple, which can achieve the highest reported Seebeck coefficient of −9.9 mV K^–1 when the hot side is above the boiling point of acetone. Vaporization entropy of acetone increases the total entropy change in the conversion of iso-propanol to acetone. In addition, a concentration gradient of acetone caused by evaporation and condensation increases the cell voltage significantly. Stable performance of the thermocell is enabled by a Pt–Sn catalyst operating in a neutral pH electrolyte solution. The possibility of utilizing a liquid–gas phase change to increase the Seebeck coefficient of thermocells opens a new venue for exploration

Rationalization of Au Concentration and Distribution in AuNi@Pt Core–Shell Nanoparticles for Oxygen Reduction Reaction

Improving the activity and stability of Pt-based core–shell nanocatalysts for proton exchange membrane fuel cells while lowering Pt loading has been one of the big challenges in electrocatalysis. Here, using density functional theory, we report the effect of adding Au as the third element to enhance the durability and activity of Ni@Pt core–shell nanoparticles (NPs) during the oxygen reduction reaction (ORR). Our results show that the durability and activity of a Ni@Pt NP can be finely tuned by controlling Au concentration and distribution. For a NiAu@Pt NP, the durability can be greatly promoted by thermodynamically favorable segregation of Au to replace the Pt atoms at vertex, edge, and (100) facets on the shell, while still keeping the ORR activity on the active Pt(111) shell as high as that of Ni@Pt nanoparticles. Such behavior strongly depends on a direct interaction with the Ni interlayer. Our results not only highlight the importance of interplay between surface strain on the shell and the interlayer–shell interaction in determining the durability and activity but also provide guidance on how to maximize the usage of Au to optimize the performance of core–shell (Pt) nanoparticles. Such understanding has allowed us to discover a novel NiAu@Pt nanocatalyst for the ORR

Size and Shape Effects of Pd@Pt Core–Shell Nanoparticles: Unique Role of Surface Contraction and Local Structural Flexibility

In this article, we present a density functional theory (DFT) study of nanoparticles (NPs) using a more realistic particle model, which allows us to model Pd@Pt core–shell NPs in size of 1–3 nm (number of atoms: 35–405) and shape [tetrahedron (TH); sphere-like truncated octahedron (SP)] precisely. Our results show that the size and shape have significant effects on the stability and activity of a Pd@Pt NP toward the oxygen reduction reaction (ORR). More importantly it is found for the first time that the variation in activity with particle size is shape-dependent. In addition, under the ORR conditions the adsorbate-driven structural changes on the terraces of nanoparticles can occur, which is relevant for understanding the observed activity and stability. According to our DFT calculations, the catalytic behaviors of Pd@Pt nanoparticles are associated with the surface contraction (compressive strain) and the local structural flexibility, which are strongly size- and shape-dependent. Our study demonstrates the importance of modeling more realistic catalysts and in situ study under reaction conditions to draw valid conclusions for nanocatalysts

Complex Catalytic Behaviors of CuTiO_<i>x</i> Mixed-Oxide during CO Oxidation

Mixed metal oxides have attracted considerable attention in heterogeneous catalysis due to the unique stability, reactivity, and selectivity. Here, the activity and stability of the CuTiO_<i>x</i> monolayer film supported on Cu(111), CuTiO_<i>x</i>/Cu­(111), during CO oxidation was explored using density functional theory (DFT). The unique structural frame of CuTiO_<i>x</i> is able to stabilize and isolate a single Cu⁺ site on the terrace, which is previously proposed active for CO oxidation. However, it is not the case, where the reaction via both the Langmuir–Hinshelwood (LH) and the Mars-van Krevelen (M-vK) mechanisms are hindered on such single Cu⁺ site. Upon the formation of step-edges, the synergy among Cu^δ+ sites, TiO_<i>x</i> matrix, and Cu(111) is able to catalyze the reaction well. Depending on temperatures and partial pressure of CO and O₂, the surface structure varies, which determines the dominant mechanism. In accordance with our results, the Cu^δ+ ion alone does not work well for CO oxidation in the form of single sites, while the synergy among multiple active sites is necessary to facilitate the reaction

Mechanism of Oxygen Reduction Reaction on Pt(111) in Alkaline Solution: Importance of Chemisorbed Water on Surface

We report a detailed mechanistic study of the oxygen reduction reaction (ORR) on Pt(111) in alkaline solution, combining density functional theory and kinetic Monte Carlo simulations. A complex reaction network including four possible pathways via either 2e^– or 4e^– transfer is established and is able to reproduce the experimental measured polarization curve at both low- and high-potential regions. Our results show that it is essential to account for solvation by water and the dynamic coverage of *OH to describe the reaction kinetics well. In addition, a chemisorbed water (*H₂O)-mediated mechanism including 4e^– transfers is identified, where the reduction steps via *H₂O on the surface are potential-independent and only the final removal of *OH from the surface in the form of OH^–(aq) contributes to the current. For the ORR in alkaline solutions, such a mechanism is more competitive than the associative and dissociative mechanisms typically used to describe the ORR in acid solution. Finally, *OH and **O₂ intermediates are found to be critically important for tuning the ORR activity of Pt in alkaline solution. To enhance the activity, the binding of Pt should be tuned in such a way that *OH binding is weak enough to release more surface sites under working conditions, while **O₂ binding is strong enough to enable the ORR via the 4e^– transfer mechanism

Palladium-Catalyzed Aryl C(sp²)–H Bond Hydroxylation of 2‑Arylpyridine Using TBHP as Oxidant

An efficient synthesis of phenols via Pd-catalyzed, pyridyl-directed homogeneous hydroxylation of the aryl C–H bond was developed, in which <i>tert</i>-butyl hydroperoxide was used as the sole oxidant. The method had a broad group tolerance and was available for both electron-rich and electron-deficient substrates. The reaction of a series of 2-arylpyridine derivatives gave the <i>ortho</i>-hydroxylation products in moderate to good yields