Добірка наукової літератури з теми "Inserts ATPM"

In micro-injection molding, the interaction between the polymer and the mold insert has an important effect on demolding quality of nanostructure. An all-atom molecular dynamics simulation method was performed to study the effect of nanostructure shape, interfacial adhesion energy, and mold insert material on demolding quality of nanostructures. The deformation behaviors of nanostructures were analyzed by calculating the non-bonded interaction energies, the density distributions, the radii of gyration, the potential energies, and the snapshots of the demolding stage. The nanostructure shape had a direct impact on demolding quality. When the contact areas were the same, the nanostructure shape did not affect the non-bonded interaction energy at PP-Ni interface. During the demolding process, the radii of gyration of molecular chains were greatly increased, and the overall density was decreased significantly. After assuming that the mold insert surface was coated with an anti-stick coating, the surface burrs, the necking, and the stretching of nanostructures were significantly reduced after demolding. The deformation of nanostructures in the Ni and Cu mold inserts were more serious than that of the Al2O3 and Si mold inserts. In general, this study would provide theoretical guidance for the design of nanostructure shape and the selection of mold insert material.

Webspinners (order Embioptera) are polyneopteran insects characterized by enlarged foretarsi with silk glands, whose silk is used to produce galleries in which the insects live gregariously. The phylogenetic position of webspinners has been debated. In the present study, an almost complete mitochondrial DNA (mtDNA) sequence of Embioptera is reported for the first time. The mtDNA of a webspinner, Aposthonia japonica , has the 13 protein-coding genes (PCGs) generally found in metazoan mtDNA sequences. There is a translocation of a large region including atp6, atp8, cox3, nad3, and nad5 as well as a duplication of the 12S rRNA gene. The rearrangement does not seem to affect nucleotide composition, although amino acid composition in some parts of the mtDNA is biased compared with other Polyneoptera species. Based on phylogenetic analyses using nucleotide sequences of all PCGs concatenated with two rRNA genes and the amino acid sequences of all PCGs, A. japonica is sister to Verophasmatodea, a suborder of typical stick and leaf insects.

Strain S658T was isolated from a Lotus corniculatus nodule in a soil sample obtained in Uruguay. Phylogenetic analysis of the 16S rRNA gene and atpD gene showed that this strain clustered within the genus Phyllobacterium . The closest related species was, in both cases, Phyllobacterium trifolii PETP02T with 99.8 % sequence similarity in the 16S rRNA gene and 96.1 % in the atpD gene. The 16S rRNA gene contains an insert at the beginning of the sequence that has no similarities with other inserts present in the same gene in described rhizobial species. Ubiquinone Q-10 was the only quinone detected. Strain S658T differed from its closest relatives through its growth in diverse culture conditions and in the assimilation of several carbon sources. It was not able to reproduce nodules in Lotus corniculatus. The results of DNA–DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain should be classified as a representative of a novel species of the genus Phyllobacterium , for which the name Phyllobacterium loti sp. nov. is proposed. The type strain is S658T( = LMG 27289T = CECT 8230T).

The first PGeP pincer-type germylene has been synthesized. Its divalent Ge atom easily inserts into M–M and M–Cl bonds, giving rise to products that contain a PGeP bridging germylene or a PGeP pincer chlorogermyl ligand.

In test mode test patterns are applied in random fashion to the circuit under circuit. This increases switching transition between the consecutive test patterns and thereby increases dynamic power dissipation. The proposed ring counter based ATPG reduces vertical switching transitions by inserting test vectors only between the less correlative test patterns. This paper presents the RC-ATPG with an external circuit. The external circuit consists of XOR gates, full adders, and multiplexers. First the total number of transitions between the consecutive test patterns is determined. If it is more, then the external circuit generates and inserts test vectors in between the two test patterns. Test vector insertion increases the correlation between the test patterns and reduces dynamic power dissipation. The results prove that the test patterns generated by the proposed ATPG have fewer transitions than the conventional ATPG. Experimental results based on ISCAS’85 and ISCAS’89 benchmark circuits show 38.5% reduction in the average power and 50% reduction in the peak power attained during testing with a small size decoding logic.

AbstractThe weevils Eucryptorrhynchus chinensis and Eucryptorrhynchus brandti (Coleoptera: Curculionidae), are two of the most important pests of the tree-of-heaven, Ailanthus altissima, which is found throughout China. In this study, the complete mitogenomes of the two weevils have been sequenced using Illumina HiSeqTM 2000. The mitogenomes of E. chinensis and E. brandti are 15,628bp and 15,597bp long with A+T contents of 77.7% and 76.6%, respectively. Both species have typical circular mitochondrial genomes that encode 36 genes. Except the deficiency of tRNA-Ile, the gene composition and order of E. chinensis and E. brandti are identical to the inferred ancestral gene arrangement of insects. In both mitochondrial genomes, the start codons for COI and ND1 are AAT and TTG, respectively. A5bp motif (TACTA) is detected in intergenic region between the tRNA-Ser (UCN) and ND1 genes. The ATP8/ATP6 and ND4L/ND4 gene pairs appear to overlap four or seven nucleotides (ATAA/ATGATAA) in different reading frames. The complete sequences of AT-rich region have two regions including tandem repeats. The study identifies useful genetic markers for studying the population genetics, molecular identification and phylogeographics of Eucryptorrhynchus weevils. The features of the mitochondrial genomes are expected to be valuable in

Analysis of the honeydew from an as yet undescribed, though distinctive, Brazilian Stigmacoccus sp. (near S. asper Hempel) by paper chromatography, Fast atom bombardment (FAB-MS) and Gas chromatography-mass spectrometry (GC-MS) identified fructose and glucose as monosaccharides and sucrose, maltose, trehalulose, trehalose and a hexose-hexitol as disaccharides. Erlose and glucosyl erlose have been identified as the tri- and tetra-saccharides in Stigmacoccus sp. and characterised for the first time in scale insects by modern techniques of linkage analysis. The same erlose oligosaccharides were recognised in honeydew of the common scale insect Coccus hesperidum L., together with the pentamer of this series, maltosyl erlose, therefore recognising that specific metabolic transformations of sugars into this oligomeric series occur rather widely in Coccoidea scale insects.

Telah dilakukan pelapisan menggunakan Titanium Alumunium Nitrid (TIAlN) dengan metode PVD Coating (Physical Vapour Diposition) dan TD (Thermal Difusion) untuk perlakuan permukaan baja perkakas SKD11 sebagai material Insert Die komponen mesin Stamping Press setelah perlakuan hardening. Perlakuan permukaan dimaksudkan untuk meningkatkan kualitas permukaan khususnya kekerasan dan perubahan struktur mikro yang terjadi. Untuk mengetahui tingkat keberhasilan dari perlakuan permukaan tersebut dilakukan dengan memvariasi waktu proses, masing masing 2 sample diproses pada 4 jam, 5 jam dan 6 jam dengan temperatur proses masing-masing 400ᴼ C. Kemudian satu dari tiap variable sample tersebut di panaskan pada suhu 1000ᴼ C selama 1 jam, pendinginan dilalukan dengan udara bebas tanpa proses quenching Untuk mengetahui hasilnya dilakukan uji kekerasan mikro Vickers, pengamatan struktur mikro Scanning Eectron Microscope (SEM), dan pengujian komposisi dengan Energy Defersif Sepectroscopy (EDS) untuk mengetahui tingkat penyerapan material terdifusi. Hasil menunjukan bahwa SKD11 yang dilapisi TiAlN dengan metode PVD selama 6 jam menghasilkan lapisan yang paling keras yaitu 1363 HV dengan ketebalan lapisan 5,3µm. Proses pemanasan 1000⁰C selama 1 jam pada sample mengakibatkan penurunan kekerasan sample dan lapisan permukaan sample menjadi lebih tebal hingga 50µm. Penambahan lapisan diakibatkan oleh terdifusinya atom atom yang menyusun lapisan TiAlN ke dalam substrat serta keluarnya atom atom penyusun lapisan hingga membentuk lapisan kompleks.

Due to the adhesion between the polymer melt and nickel (Ni) mold insert in the micro injection molding process, deformation defects frequently occur when the microstructures are demolded from the insert. In this study, self-assembled alkanethiols were applied to modify the surface of Ni mold insert to reduce its surface energy. Experimental trials were undertaken to explore the effect of alkanethiols coating on the replication quality. After that, molecular dynamics (MD) simulation was then used to investigate the adhesion behavior between the self-assembled coating and polypropylene (PP) by establishing three different types of alkanethiol material. The interaction energy, the potential energy change and radial distribution function were calculated to study the anti-adhesion mechanism. Experimental results show that all the three coatings can effectively decrease the adhesion and therefore promote the replication fidelity. It is demonstrated in MD simulation that the adhesion mainly comes from the van der Waals (vdW) force at the interface. The arrangement of sulfur atom on the Ni surface results in different absorbing behaviors. Compared with that of the PP–Ni interface, the interfacial energy and adhesion work after surface treatment is significantly reduced.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.03.01 – процеси механічної обробки, верстати та інструменти. – Національний технічний університет "Харківський політехнічний інститут". Харків, 2017. Дисертаційна робота присвячена розв'язанню задачі обробки нового інструментального матеріалу дрібнозернистих алмазно-твердосплавних пластин АТПМ, встановленню фізичних особливостей процесу алмазно-іскрового шліфування, встановленню та аналізу якісних закономірностей, досягненню високої продуктивності і найменшою сумарною технологічної собівартості. Досліджувалися фізичні особливості процесу АІШ пластин АТПМ на основі аналізу енергоємності процесу і коефіцієнтів шліфування, представлені особливості зносу алмазних кругів. Встановлено особливості формування шорсткості поверхні обробленого шару надтвердих матеріалів в залежності від приведеного профілю алмазного круга. Визначено на основі стійкісних випробувань оптимальні значення режимів шліфування лезового інструменту, при яких забеспечуються найменші значення технологічної собівартості у споживача.
Thesis for the degree of candidate of technical sciences, specialty 05.03.01 – machining processes, machines and tools. – National Technical University "Kharkov Polytechnic Institute". Kharkov, 2017. The thesis is devoted to the problem of handling the new tool material fine grain diamond-carbide inserts, ATPM, establishing the physical characteristics of the process of diamond-spark grinding, the establishment and analysis of qualitative regularities, to achieve high performance and lowest total technological cost. Studied the physical characteristics of the process of spark-diamond grinding plates, ATPM based on the analysis of the energy intensity of the process and factors of grinding, the features of the wear of diamond wheels. Features of formation of a roughness of a surface processed layer of superhard materials, depending on the given profile of the diamond wheel. Determined on the basis of stoikosty testing the optimal mode of grinding the cutting edge of the instrument, which can obtain the lowest value of the technology cost from the consumer.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.03.01 – процеси механічної обробки, верстати та інструменти. – Національний технічний університет "Харківський політехнічний інститут". Харків, 2017. Дисертаційна робота присвячена розв'язанню задачі обробки нового інструментального матеріалу дрібнозернистих алмазно-твердосплавних пластин АТПМ, встановленню фізичних особливостей процесу алмазно-іскрового шліфування, встановленню та аналізу якісних закономірностей, досягненню високої продуктивності і найменшою сумарною технологічної собівартості. Досліджувалися фізичні особливості процесу АІШ пластин АТПМ на основі аналізу енергоємності процесу і коефіцієнтів шліфування, представлені особливості зносу алмазних кругів. Встановлено особливості формування шорсткості поверхні обробленого шару надтвердих матеріалів в залежності від приведеного профілю алмазного круга. Визначено на основі стійкісних випробувань оптимальні значення режимів шліфування лезового інструменту, при яких забеспечуються найменші значення технологічної собівартості у споживача.
Thesis for the degree of candidate of technical sciences, specialty 05.03.01 – machining processes, machines and tools. – National Technical University "Kharkov Polytechnic Institute". Kharkov, 2017. The thesis is devoted to the problem of handling the new tool material fine grain diamond-carbide inserts, ATPM, establishing the physical characteristics of the process of diamond-spark grinding, the establishment and analysis of qualitative regularities, to achieve high performance and lowest total technological cost. Studied the physical characteristics of the process of spark-diamond grinding plates, ATPM based on the analysis of the energy intensity of the process and factors of grinding, the features of the wear of diamond wheels. Features of formation of a roughness of a surface processed layer of superhard materials, depending on the given profile of the diamond wheel. Determined on the basis of stoikosty testing the optimal mode of grinding the cutting edge of the instrument, which can obtain the lowest value of the technology cost from the consumer.

Abstract Premature failure of a diamond coated tool often results from a poor adhesion of the coating to and shortens the lifetime of the tool. This study presents the results of increasing the adhesion strength of diamond coatings on cutting tool inserts by pretreating the inserts with sandblasting technique to obtain a desirable surface morphology of the inserts. A geometric model representing the ideal surface morphology is established to enhance the nucleation density and adhesion strength of diamond coatings. Diamond coating experiment is conducted on the substrates of four different sample groups. Indentation and wear tests are performed on diamond coated inserts to evaluate the effect of sandblasting on the adhesion strength of the coatings. A theoretical analysis is provided on the formation and growth of atom clusters in terms of the contact angle and the thermodynamic barrier of a substrate to predict diamond nucleation. The theoretical prediction has a good agreement with the experimental results obtained in this study and by Dennig et al. [1, 2].

In recent years, a large number of nano-size semiconductors have been investigated for their potential applications in photovoltaic cells, optical sensor devices, and photocatalysts [1, 2, 3]. Nano-size semiconductor particles have many interesting properties due mainly to their size-dependent electronic and optical properties. Appropriately, many speciality of nanomaterials such as CdS and ZnS semiconductor particles, and other metal oxides such as ZnO and lithium-titanate oxide (LTO) have been prepared. However, most of them were prepared with toxic reactants and/or complex multistep reaction processes. Particularly, it is quite difficult to produce LTO nanoparticles, since it typically requires wearisome conditions such as very high temperature over 1000 °C, long producing times, and so on. To overcome such problems, various core/shell type nanocrystals were prepared through different methods such as the hydrothermal synthetic method, microwave, and sonochemistry. Also many coating methods on inorganic oxide nanoparticles were tried for the preparations of various core-shell type nanocrystals. Sonoluminescence (SL) is a light emission phenomenon associated with the catastrophic collapse of a gas bubble oscillating under an ultrasonic field [4]. Light emission of single bubble sonoluminescence (SBSL) is characterized by picosecond flashes of the broad band spectrum extending to the ultraviolet [5, 6]. The bubble wall acceleration has been found to exceed 1011 g at the moment of bubble collapse. Recently observed results of the peak temperature and pressure from the sonoluminescing gas bubble in sulfuric acid solutions [9] were accurately predicted by the hydrodynamic theory for sonoluminescence phenomena [7, 10, 11, 12], which provides a clue for understanding sonochemical reactions inside the bubble and liquid layer adjacent to the bubble wall. Sonochemistry involves an application of sonoluminescence. The intense local heating and high pressure inside the bubbles and liquid adjacent bubble wall from such collapse can give rise to unusual effects in chemical reactions. The estimated temperature and pressure in the liquid zone around the collapsing bubble with equilibrium radius 5 μm, an average radius of bubbles generated in a sonochemical reactor at a driving frequency of 20 kHz with an input power of 179 W, is about 1000 °C and 500 atm, respectively. At the proper condition, a lot of transient bubbles are generated and collapse synchronistically to emit blue light when high power ultrasound is applied to liquid, and it is called multibubble sonoluminescence (MBSL). Figure 1 shows an experimental apparatus for MBSL with a cylindrical quartz cell, into which a 5 mm diameter titanium horn (Misonix XL2020, USA) is inserted [13]. The MBSL facilitates the transient supercritical state [14].in the liquid layer where rapid chemical reactions can take place. In fact, methylene blue (MB), which is one of a number of typical textile dyestuffs, was degraded very fast at the MBSL condition while MB does not degrade under simple ultrasonic irradiation [13]. MBSL has been proven to be a useful technique to make novel materials with unusual properties. In our study, various metal oxides such as ZnO powder [15], used as a primary reinforcing filler for elastomer, homogeneous Li4Ti5O12 nanoparticles [16], used for electrode materials, and core/shell nanoparticles such as CdS coating on TiO2 nanoparticles [17] and ZnS coating on TiO2 nanoparticles [18], which are very likely to be useful for the development of inorganic dye-sensitized solar cells, were synthesized through a one pot reaction under the MBSL condition. Figure 2 shows the XRD pattern of ZnO nanoparticles synthesized from zinc acetate dehydrate (Zn(CH3CO2)2 · 2H2O, 99.999%, Aldrich) in various alcohol solutions with sodium hydroxide (NaOH, 99.99%, Aldrich) at the MBSL condition. The XRD patterns of all powers indicate hexagonal zincite. The XRD pattern for the ZnO nanoparticles synthesized is similar to the ZnO powder produced by a modified sol-gel process and subsequent heat treatment at about 600 °C [19] as shown in Fig.3. The average particle diameter of ZnO powder is about 7 nm. A simple sonochemical method for producing homogeneous LTO nanoparticles, as shown schematically in Fig. 4. First, LiOH and TiO2 nanoparticles were used to prepare LiOH-coated TiO2 nanoparticles as shown in Fig.5. Second, the resulting nanoparticles were thermally treated at 500 °C for 1 hour to prepare LTO nanoparticles. Figure 6 shows a high resolution transmission electron microscope image of LTO nanoparticles having an average grain size of 30–40 nm. All the nanoparticle synthesized are very pure in phase and quite homogeneous in their size and shape. Recently we succeeded in synthesizing a supported nickel catalyst such as Ni/Al2sO3, MgO/Al2O3 and LaAlO3, which turned out to be effective for methane decomposition [20]. Sonochemistry may provide a new way to more rapidly synthesize many specialty nanoparticles with less waste [21]. This clean technology enables the preparation of new materials such as colloids, amorphous particles [22], and various alloys.