Komposit Skin Hybrid Berpenguat Serat Bambu Acak 50% Dan Serat Rami Anyaman 50% Bermatrik Polyester Terhadap Kekuatan Tarik, Bending Dan Impact

The objective of this study was to investigate the effect of reinforcement volume of random bamboo fiber and woven fiber combination to tensile strength, bending and polyester-matrix impact with multiplex comparator. The pattern of failure is observed with macro photos. The main research materials are bamboo fiber and hemp fiber with unsaturated polyester resin 157 BQTN and MEKPO hardener with concentration of 1%. The composite is made by press printing (pressmold). The fraction of hybrid composite skin reinforcement volume is 10%, 20%, 30%, 40% and 50%. The test is tensile test, bending test, impact test and density with reference to ASTM D-3039 standard for tensile test, ASTM D-790 for bending test, ASTM D-6110 for impact test and ASTM C-271 for density test. The results of this study showed that the optimum hybrid composite skin tensile strength was found in the volume fraction of 40% fiber with a value of 31.723 MPa. Optimum hybrid bending skin strength is found in the fraction of 40% fiber with a value of 68.85 MPa. For optimum impact strength is found in the volume fraction of 0.27646 J / mm². The highest density in the volume fraction of 40% fiber is 1,216 gr / cm³. Mechanism of tensile and bend test failure pattern occurs fibre pull out, for impact test occurs fiber fracture failure pattern. For comparative strength of hybrid composite skins with multiplex, hybrid composite skin proved to have higher strength than multiplex, multiplex only has 12,743 MPa tensile strength, for multiplex bending power of 26,60 MPa, for multiplex impact strength 0,01629 j /mm² and multiplex has the lowest density of 0.040 gr / cm³

Methyl-Rotation Dynamics in Metal-Organic Frameworks Probed with Terahertz Spectroscopy

In ZIF-8 and its cobalt analogue ZIF-67, the imidazolate methyl-groups, which point directly into the void space, have been shown to freely rotate - even down to cryogenic temperatures. Using a combination of experimental terahertz time-domain spectroscopy, low-frequency Raman spectroscopy, and state-of-the-art ab initio simulations, the methyl-rotor dynamics in ZIF-8 and ZIF-67 are fully characterized within the context of a quantum-mechanical hindered-rotor model. The results lend insight into the fundamental origins of the experimentally observed methyl rotor dynamics, and provide valuable insight into the nature of the weak interactions present within this important class of materials

Application of Raspberry pi for protecting property

The Raspberry pi is a super powerful, tiny computer having the advantage of SD card which is invented without despair of inspiring generation of learners to be creative. The computer user ARM (Advanced RISC Machines) processor at the heart of the Raspberry pi system is a Broadcom BCM2835 system on chip, SOC (system operation computer….) multimedia processor this review paper provides the description of the Raspberry pi technology which is a super powerful computer. It introduces the overall system of architecture and the design of hardware components are presented in details. i

Pengaruh Posisi Saluran Masuk (In-Gate)Pada Hasil Coran Produk Connecting Rod Dari Bahan Aluminium

A lot of research has been done about the effect of the in-gate, so researchers want to develop pre-existing research by varying the inlets to the left, center and right by testing shrinkage, density, porosity, microstructure, and hardness. The researcher uses sand as a media in the casting process, so this method is commonly called Sand Casting. The test results obtained the largest shrinkage value at the middle in-gate position of 1.42%, followed by the left in-gate position 1.21%, and the smallest shrinkage occurred at the right in-gate position of 1.11%. At the density value obtained the largest density value at the position of the middle in-gate of 3.21 g/ml 3 , then at the position of the left in-gate of 2.48 g/ml 3 , and the lowest density value occurs at the right in-gate position of 2.27 g/ml 3 . In the hardness test using the Brinell hardness test the highest hardness value was obtained at the center ingate position with a value of 79.6 BHN, then the left in-gate channel position was 79.2 BHN, and the smallest value at the right in-gate position was 78.7 BHN. From micro photo testing the results of the greatest hardness were found in the increasingly tightly arranged elements. The difference in in-gate position affects the shrinkage value. The greater the value of shrinkage, the greater the value of its density. Keywords: In-gate, Connecting Rod, Shrinkage, Hardness, Porosity, Density, Microstructure, Sand Casting

Pengaruh Posisi Saluran Masuk (In-Gate)Pada Hasil Coran Produk Connecting Rod Dari Bahan Aluminium

A lot of research has been done about the effect of the in-gate, so researchers want to develop pre-existing research by varying the inlets to the left, center and right by testing shrinkage, density, porosity, microstructure, and hardness. The researcher uses sand as a media in the casting process, so this method is commonly called Sand Casting. The test results obtained the largest shrinkage value at the middle in-gate position of 1.42%, followed by the left in-gate position 1.21%, and the smallest shrinkage occurred at the right in-gate position of 1.11%. At the density value obtained the largest density value at the position of the middle in-gate of 3.21 g/ml 3 , then at the position of the left in-gate of 2.48 g/ml 3 , and the lowest density value occurs at the right in-gate position of 2.27 g/ml 3 . In the hardness test using the Brinell hardness test the highest hardness value was obtained at the center ingate position with a value of 79.6 BHN, then the left in-gate channel position was 79.2 BHN, and the smallest value at the right in-gate position was 78.7 BHN. From micro photo testing the results of the greatest hardness were found in the increasingly tightly arranged elements. The difference in in-gate position affects the shrinkage value. The greater the value of shrinkage, the greater the value of its density. Keywords: In-gate, Connecting Rod, Shrinkage, Hardness, Porosity, Density, Microstructure, Sand Casting

Pengaruh Variasi Media Cetakan Pasir, Cetakan Logam Dan Cetakan RCS ( Resin Coated Sand ) Terhadap Produk Coran Alumunium

The use of printed material in the cast product has the nature and character of its own. These properties greatly affect the quality of the cast product. The purpose of this study was to determine the effect of variations in the mold of the quality of the cast, cast defects and hardness. This study uses aluminum used or former, which melted in the kitchen krusible, a variation of the mold used three types: sand molds, metal molds and mold RCS (Resin Coated Sand). To determine the shrinkage defects dimensional objects compare the original with the results of specimens of each specimen mold. Defects porosity can be seen by looking for value calculation of density guided by the standard ASTM E-252, hardness testing using a test Brinell with ASTM E10, testing microstructure done with standard ASTM E3 by viewing a specimen under a microscope and chemical composition testing done with standard ASTM E1251 argon gas-fired way to the surface of the specimen, so the result will be read on a computer. The percentage value of depreciation for the wet sand molds variation of 0.61%, 0.64% metal mold and to mold RCS (Resin Coated Sand) by 0.59%. The research result of depreciation show that the metal mold has a shrinkage value of high and low of RCS (Resin Coated Sand) and mold the wet sand between the two metal molds and mold RCS (Resin Coated Sand) shrinkage occurs because the conductivity of each mold to absorb heat so the higher conductivity makes the metal solidification fast and also affect the large grains are seen on the microstructure, rapid freezing to make the grain to be small with an elongated shape and the distance between the grain elevator. At the porosity is obtained from the density, wet sand mold ρ = 2.513, metal molds ρ = 2.597 and RCS (Resin Coated Sand) ρ = 2.506 density, the higher the value of the material is a little more dense and porosity. The density of material related to violence are also higher, obtained on wet sand molds Brinell testing at 58.256 BHN, amounting to 61.219 BHN metal mold and mold RCS (Resin Coated Sand) 57.124 BHN. The chemical composition of the material was found elements (Al) 91.43% (Si) 4.07%, (Zn) 2.13%, (Fe) 1.76%, (Cu) 0.147%, (Cr) 0.175% and the element more so than the elements present this material include metal aluminum silicon alloy (Al-Si)

More on integrable structures of superstrings in AdS(4) x CP(3) and AdS(2) x S(2) x T(6) superbackgrounds

In this paper we continue the study, initiated in arXiv:1009.3498 and arXiv:1104.1793, of the classical integrability of Green-Schwarz superstrings in AdS(4) x CP(3) and AdS(2) x S(2) x T(6) superbackgrounds whose spectrum contains non-supercoset worldsheet degrees of freedom corresponding to broken supersymmetries in the bulk. We derive an explicit expression, to all orders in the coset fermions and to second order in the non-coset fermions, which extends the supercoset Lax connection in these backgrounds with terms depending on the non-coset fermions. An important property of the obtained form of the Lax connection is that it is invariant under Z_4-transformations of the superisometry generators and the spectral parameter. This demonstrates that the contribution of the non-coset fermions does not spoil the Z_4-symmetry of the super-coset Lax connection which is of crucial importance for the application of Bethe-ansatz techniques. The expressions describing the AdS(4) x CP(3) and AdS(2) x S(2) x T(6) superstring sigma--models and their Lax connections have a very similar form. This is because their amount of target-space supersymmetries complement each other to 32=24+8, the maximal number of 10d type II supersymmetries. As a byproduct, this similarity has allowed us to obtain the form of the geometry of the complete type IIA AdS(2) x S(2) x T(6) superspace to all orders in the coset fermions and to the second order in the non-coset ones.Comment: 28 pages; v2: References adde

Malignant melanoma of the rectum: a case report

<p>Abstract</p> <p>Introduction</p> <p>Anorectal melanoma represents an unusual but important presentation of rectal malignancy. There have only been a few cases reported and the optimum management for this condition is still undecided, however, prompt diagnosis is essential. We have outlined current treatment options.</p> <p>Case presentation</p> <p>We report a case of malignant melanoma of the rectum in a 55-year-old Caucasian man presenting as an emergency with rectal bleeding. Biopsies were taken of the fleshy mass found on digital examination, which confirmed malignant melanoma. No distant metastases were found. He underwent an abdominoperineal resection. We report the surgical management of this rare and aggressive malignancy.</p> <p>Conclusion</p> <p>Treatment options for this condition are divergent. Surgical management varies from wide local excision to abdominoperineal resection. Clinical awareness in both medical and surgical clinics is required for prompt diagnosis and treatment.</p

The role of mutation rate variation and genetic diversity in the architecture of human disease

Background We have investigated the role that the mutation rate and the structure of genetic variation at a locus play in determining whether a gene is involved in disease. We predict that the mutation rate and its genetic diversity should be higher in genes associated with disease, unless all genes that could cause disease have already been identified. Results Consistent with our predictions we find that genes associated with Mendelian and complex disease are substantially longer than non-disease genes. However, we find that both Mendelian and complex disease genes are found in regions of the genome with relatively low mutation rates, as inferred from intron divergence between humans and chimpanzees, and they are predicted to have similar rates of non-synonymous mutation as other genes. Finally, we find that disease genes are in regions of significantly elevated genetic diversity, even when variation in the rate of mutation is controlled for. The effect is small nevertheless. Conclusions Our results suggest that gene length contributes to whether a gene is associated with disease. However, the mutation rate and the genetic architecture of the locus appear to play only a minor role in determining whether a gene is associated with disease

Electric Field-Tuned Topological Phase Transition in Ultra-Thin Na3Bi - Towards a Topological Transistor

The electric field induced quantum phase transition from topological to conventional insulator has been proposed as the basis of a topological field effect transistor [1-4]. In this scheme an electric field can switch 'on' the ballistic flow of charge and spin along dissipationless edges of the two-dimensional (2D) quantum spin Hall insulator [5-9], and when 'off' is a conventional insulator with no conductive channels. Such as topological transistor is promising for low-energy logic circuits [4], which would necessitate electric field-switched materials with conventional and topological bandgaps much greater than room temperature, significantly greater than proposed to date [6-8]. Topological Dirac semimetals(TDS) are promising systems in which to look for topological field-effect switching, as they lie at the boundary between conventional and topological phases [3,10-16]. Here we use scanning probe microscopy/spectroscopy (STM/STS) and angle-resolved photoelectron spectroscopy (ARPES) to show that mono- and bilayer films of TDS Na3Bi [3,17] are 2D topological insulators with bulk bandgaps >400 meV in the absence of electric field. Upon application of electric field by doping with potassium or by close approach of the STM tip, the bandgap can be completely closed then re-opened with conventional gap greater than 100 meV. The large bandgaps in both the conventional and quantum spin Hall phases, much greater than the thermal energy kT = 25 meV at room temperature, suggest that ultrathin Na3Bi is suitable for room temperature topological transistor operation