Journal articles: 'Cyclar process'

1

Mittal, Sonam, and Reena Saini. "Process Life Cycle of Usability Engineering." International Journal of Scientific Research 2, no. 9 (June 1, 2012): 74–76. http://dx.doi.org/10.15373/22778179/sep2013/26.

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Sumita, Ushio, and Kazuki Takahashi. "DYNAMIC ANALYSIS OF A REWARD PROCESS DEFINED ON A CYCLIC RENEWAL PROCESS WITH APPLICATIONS TO PREVENTIVE MAINTENANCE PROBLEMS." Journal of the Operations Research Society of Japan 52, no. 3 (2009): 283–306. http://dx.doi.org/10.15807/jorsj.52.283.

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Johar, Mahzan, Mohamad Shahrul Effendy Kosnan, and Mohd Nasir Tamin. "Cyclic Cohesive Zone Model for Simulation of Fatigue Failure Process in Adhesive Joints." Applied Mechanics and Materials 606 (August 2014): 217–21. http://dx.doi.org/10.4028/www.scientific.net/amm.606.217.

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Progressive failure process of adhesive joint under cyclic loading is of particular interest in this study. Such fatigue failure is described using damage mechanics with the assumed cohesive behaviour of the adhesive joint. Available cohesive zone model for monotonic loading is re-examined for extension to capture cyclic damage process of adhesive joints. Damage evolution in the adhesive joint is expressed in terms of cyclic degradation of interface strength and stiffness. Mixed-mode fatigue fracture of the joint is formulated based on relative displacements and strain energy release rate of the interface. A power-law type variation for each of these cohesive zone model parameters with accumulated load cycles is assumed in the presence of limited experimental data on cyclic interface fracture process. The cyclic cohesive zone model (CCZM) is implemented in commercial finite element analysis code and the model is validated using adhesively bonded 2024-T3 aluminium substrates with epoxy-based adhesive film (FM73M OST). The CCZM model is then examined for cyclic damage evolution characteristics of the adhesive lap joint subjected to cyclic displacement of Δδ = 0.1 mm, R=0 so as to induce shear-dominant fatigue failure. Results show that the cyclic interface damage started to initiate and propagate symmetrically from the both overlap edges and degradation of interface strength and stiffness started to accumulate after 0.5 cycles of displacement elapsed. The predicted results are consistent with the mechanics of relatively brittle interface failure process.

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Jastrzebska, M. "The Influence of Selected Parameters of Cyclic Process on Cohesive Soils Shear Characteristics at Small Strain / Wpływ Wybranych Parametrów Procesu Cyklicznego Na Charakterystyki Scinania Gruntów Spoistych W Zakresie Małych Odkształcen." Archives of Civil Engineering 56, no. 1 (March 1, 2010): 89–107. http://dx.doi.org/10.2478/v.10169-010-0005-x.

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Abstract The subject of the paper comprises a cohesive soil response to a cyclic loading applied in the range of small strains (10-5 ÷ 10-3). To this end tests of undrained cyclic shear in a triaxial compression apparatus were carried out on homogeneous material - kaoline from Tułowice. The tests were carried out on a modernised test bed, enabling full saturation of samples using the back pressure method, as well as a precise, intra-chamber measurement of small strains. Maintaining a constant deviatoric stress amplitude for NC and OC soils, the effect of its size (A = 0.75 Δq or A = 0.375 Δq) as well as the influence of strain rate on material characteristics “deviatoric stress (excess pore water pressure) - axial strain” and effective stress paths were tested. While analysing the results obtained, a phenomenon of closing and stabilising initially open and moving loops were found, in contrast to proposal by Jardine [8]. The observed increments in the axial strain during cyclic loading operation, at the same levels of lateral effective stress, were greater for normally consolidated than for overconsolidated soils. At the same time, at each next cycle, these increments were smaller and smaller, assuming even the value equal to zero for the tenth cycle. Similar relationships occurred during the increase in the pore water pressure during the cyclic load action. For the set number of cycles n = 10 they were that small - max. 46% (and decreasing with each consecutive cycle) that they did not result in weakening of the material. Taking the trend of decreasing Δu increments into account it was possible to accept that the conclusion considered was right irrespective of the cycles’ number.

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Inoue, Yoriteru. "A Cyclic Process." Japan journal of water pollution research 10, no. 5 (1987): 275. http://dx.doi.org/10.2965/jswe1978.10.275.

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Chen, Qiong, Deshan Cui, Qingbing Liu, and Xianyu Tao. "Effect of Local Cyclic Loading on Direct Shear Strength Characteristics of Shear-Zone Soil." Applied Sciences 12, no. 24 (December 19, 2022): 13024. http://dx.doi.org/10.3390/app122413024.

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The reservoir landslide in the Three Gorges Reservoir Area (TGRA) often suffers from local cyclic loading scenarios produced by surge waves, groundwater level fluctuation, traffic loading, and seismic activity. However, the effects of local cyclic loading on the shear resistance of the shear-zone of the reservoir landslide are poorly understood. This study experimentally investigates the effects of local cyclic loading on the shear strength and the deformation of shear-zone material using cyclic direct shear tests. A series of cyclic direct shear tests are performed with different normal stresses, cyclic periods, and numbers of cycles. The experimental results indicate that: (1) Compared with monotonic loading, local cyclic loading can significantly decrease the shear stress of shear-zone soil. (2) Shear-zone soil exhibits greater volumetric contraction under local cyclic loading conditions than that under monotonic loading. (3) Under different vertical stresses, the differentiation of shear deformation after 40 cycles of loading was slight and virtually insignificant. The research results reveal the weakening law of the mechanical strength of shear-zone soil under local cyclic loading, which provides a foundation for investigating the mechanism of the reservoir landslide under the fluctuation of water levels.

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Jeong, Yeong-Hoon, Seong-Won Lee, and Jae-Hyun Kim. "Centrifuge Modeling for the Evaluation of the Cyclic Behavior of Offshore Wind Turbine with Tripod Foundation." Applied Sciences 11, no. 4 (February 15, 2021): 1718. http://dx.doi.org/10.3390/app11041718.

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In this study, the cyclic responses of an offshore wind turbine with a tripod foundation installed on an actual site were evaluated in a centrifuge. To understand the behavior of the turbine at the site, the site soil conditions, environmental loads, and real offshore wind turbine structure installed at the actual site were modeled by considering the centrifuge scaling law. From a series of cyclic loading tests, the cyclic responses of the tripod foundation were evaluated in terms of temporary/permanent displacements and cyclic stiffness. Moreover, the long-term behavior of the tripod foundation was predicted from the experimental results. The test results showed that the initial stiffness of the soil–foundation system decreased as the loading amplitude increased and that the stiffness increased with the number of cycles due to soil densification. The findings revealed that the cyclic behaviors of the tripod were more affected by the load amplitude than the number of cycles. In addition, the permanent rotation increased logarithmically with the number of cycles. A simple method to predict the displacement and change in the foundation stiffness of the actual wind turbine is proposed based on the results of the model tests. The results of this study also provide key insights into the long-term cyclic behavior of tripod foundations for offshore wind turbines.

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Murphy, G. J., and M. D. Houslay. "Resensitization of hepatocyte glucagon-stimulated adenylate cyclase can be inhibited when cyclic AMP phosphodiesterase inhibitors are used to elevate intracellular cyclic AMP concentrations to supraphysiological values." Biochemical Journal 249, no. 2 (January 15, 1988): 543–47. http://dx.doi.org/10.1042/bj2490543.

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Treatment of intact hepatocytes with glucagon led to the rapid desensitization of adenylate cyclase, which reached a maximum around 5 min after application of glucagon, after which resensitization ensued. Complete resensitization occurred some 20 min after the addition of glucagon. In hepatocytes which had been preincubated with the cyclic AMP phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), glucagon elicited a stable desensitized state where resensitization failed to occur even 20 min after exposure of hepatocytes to glucagon. Treatment with IBMX alone did not elicit desensitization. The action of IBMX in stabilizing the glucagon-mediated desensitized state was mimicked by the non-methylxanthine cyclic AMP phosphodiesterase inhibitor Ro-20-1724 [4-(3-butoxy-4-methoxylbenzyl)-2-imidazolidinone]. IBMX inhibited the resensitization process in a dose-dependent fashion with an EC50 (concn. giving 50% of maximal effect) of 26 +/- 5 microM, which was similar to the EC50 value of 22 +/- 6 microM observed for the ability of IBMX to augment the glucagon-stimulated rise in intracellular cyclic AMP concentrations. Pre-treatment of hepatocytes with IBMX did not alter the ability of either angiotensin or the glucagon analogue TH-glucagon, ligands which did not increase intracellular cyclic AMP concentrations, to cause the rapid desensitization and subsequent resensitization of adenylate cyclase. It is suggested that, although desensitization of glucagon-stimulated adenylate cyclase is elicited by a cyclic AMP-independent process, the resensitization of adenylate cyclase can be inhibited by a process which is dependent on elevated cyclic AMP concentrations. This action can be detected by attenuating the degradation of cyclic AMP by using inhibitors of cyclic AMP phosphodiesterase.

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Duan, Guo Sheng, Bao Lin Wu, Xiang Zhao, and Gang Zhao. "Cyclic Hardening Behavior of Extruded AZ31B Magnesium Alloy during Low Cycle Fatigue Process." Applied Mechanics and Materials 395-396 (September 2013): 234–37. http://dx.doi.org/10.4028/www.scientific.net/amm.395-396.234.

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The strain-controlled fatigue tests on extruded AZ31B magnesium alloy were conducted under the uniaxial loading with strain ratio Rε=-∞, frequency of 0.1 Hz and strain amplitude of 2% at room temperature. The cyclic hardening behavior was investigated. It was found that, during the low cycle fatigue (LCF) process, as the number of cycles increases, the stress amplitude increases corresponding to the decrease of the plastic strain amplitude. The development of dislocation density can be described as the function of the number of fatigue cycles, and the behavior can be explained well based on the dislocation density development model.

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Yang, Hong Bo, Yao Mian Wang, Lei Luo, and Ping Ping Zhang. "Ostwald Growth of Carbides in Cyclic Annealing Process of GCr15 Bearing Steel." Advanced Materials Research 374-377 (October 2011): 1805–8. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.1805.

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The spheroidization of the carbide of hot-deformed GCr15 bearing steel was investigated in cyclic annealing process. The results show that most of carbide particles become gradually smaller and more dispersed with the increase of process cycle, however, part of them start to grow for the four cycles, the growth agrees well with Ostwald Ripening Law, and it is not suitable for the further process.

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11

Yin, Jie, Yong Tang, Yong-hong Miao, and Ruo-yu Sheng. "An Experimental Investigation on Dynamic Characteristics of Soft Soils Treated by Vibration-Drainage Method." Advances in Civil Engineering 2020 (August 29, 2020): 1–12. http://dx.doi.org/10.1155/2020/8890562.

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This paper presents an experimental investigation on the dynamic characteristics of soft soils that are treated by vibration-drainage method (VDM). The representative dynamic axial strain at a given number of cycles was obtained. The VDM-treated soft soil exhibited different dynamic deformation characteristics that are not only affected by the cyclic frequency but also influenced by the vibration frequency during the treatment process. Soil specimens at different cyclic frequencies show a similar variation trend that the axial strain systematically grows with increasing number of cycles. The rate of axial strain for all specimens systematically linearly decreases with the increase of number of cycles in the log-log scale. Results showed that both axial strain and strain rate exhibit relatively lower values at a given number of cycles under the condition that the applied cyclic frequency is equal to vibration frequency. It is expected that the soil structure will be more stable if the applied cyclic frequency is close to the vibration frequency that is applied on VDM-treated soil. Therefore, the vibration frequency close to the possible dynamic loading frequency is recommended in the process of soft soil improvement via VDM in the related engineering applications.

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Iizuka, Hajime, and Akira Ohkawara. "“Ischemic” Rise of Epidermal Cyclic AMP Is a Beta-Adrenergic Adenylate Cyclase-Dependent Process." Journal of Investigative Dermatology 86, no. 3 (March 1986): 271–74. http://dx.doi.org/10.1111/1523-1747.ep12285404.

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Zeng, Zhiping, Xiangdong Huang, Weidong Wang, Bin Zhu, Zheng Zhang, and Di Wang. "Study on the Mechanical Characteristics of the Sleeper Slab Track on a Long-Span Steel Truss Bridge." Applied Sciences 11, no. 11 (June 6, 2021): 5273. http://dx.doi.org/10.3390/app11115273.

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This paper uses the long-span steel truss slab track as its research subject to analyze the new type of sleeper slab track structure with an experimental method. Firstly, a full-scale model was established in the laboratory to form a “rail–sleeper slab–self-compacting concrete cushion–steel beam” composite structure, and a fatigue test was performed on the track structure. The cyclic load was set up as a sine form with a range between 75 and 375 kN at a 5 Hz interval and 3 × 106 cycles. Based on the test, the performance of the track structure under cyclic train load was studied. Secondly, after every 106 loading cycles, the vertical static loading test and horizontal resistance test of the track structure were carried out to obtain the strain and displacement under different loading cycles. Finally, after 3 × 106 cycles of sine cyclic loading, the horizontal ultimate resistance test of the track structure was carried out to study its horizontal failure mode. The aims of this paper were to verify the applicability of the sleeper slab track, identify the mechanical properties, and determine the unfavorable position. The findings can provide an important reference for the practical use of the sleeper slab track structure.

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Esmaeili, F., F. Mehri Sofiani, and R. Broomand. "A modified counterpart of cyclic extrusion-compression: Experimental study and dislocation density-based finite element modeling." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 232, no. 6 (March 22, 2016): 465–80. http://dx.doi.org/10.1177/1464420716634744.

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In this study, strip cyclic extrusion-compression was introduced as a modified counterpart of cyclic extrusion-compression process for producing ultrafine grained strips. The strip cyclic extrusion-compression method was applied to the pure aluminum and mechanical properties of the processed strips were investigated. The ultrafine grained strips were successfully processed by applying two cycles of strip cyclic extrusion-compression. The transmission electron microscopy observations revealed that the initial microstructure was refined to 1 µm and 650 nm after the first and second cycles, respectively. The yield strength was increased 3 times and the ultimate strength was enhanced 1.5 times after the application of two cycles. The microhardness of the processed strips was increased to 46 Hv and 58 Hv after the first and second cycles, respectively. Furthermore, the fatigue tests revealed that the fatigue strength was higher in the strip cyclic extrusion-compression processed material than the un-processed one. The microstructure evolution during strip cyclic extrusion-compression was also modeled by means of a dislocation density-based finite element method. The finite element method model predicted that the microstructure was refined to 950 nm and 690 nm after the first and second cycles, respectively.

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Zhang, Wei, Xue Zheng Chen, Peng Fei Yin, Zheng Kai Xu, Bing Han, and Jia Wang. "EIS Study on the Deterioration Process of Organic Coatings under Immersion and Different Cyclic Wet-Dry Ratios." Applied Mechanics and Materials 161 (March 2012): 58–66. http://dx.doi.org/10.4028/www.scientific.net/amm.161.58.

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Under immersed and we-dry cyclic conditions, the deterioration processes of the organic coating on carbon steel surface have been comparatively studied using electrochemical techniques. The wet-dry cycles were carried out by exposure to 4 h immersion and 4h dryness (4-4h cycles) and 12h immersion and 12h dryness (12-12h cycles) conditions, respectively. The immersion condition was carry out in a 3.5% NaCl solution and drying at 298K and 50% RH. According to the EIS characteristics, the entire deterioration processes under above three mentioned conditions can be divided into three main stages, consisting of the medium penetration, corrosion initiation and corrosion extension. Comparing with the immersed, the 4-4h wet-dry cycles greatly accelerated the entire deterioration process; especially during the corrosion initiation and the corrosion extension periods, leading the paint system lose its anti-corrosive performance in a short period. However, the 12-12h wet-dry cycles decelerated the entire deterioration process, prolonging the coatings anticorrosive ability. The acceleration mechanism of the coatings and underlying metal corrosion under wet-dry cycles was discussed based on the above results.

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Goraczniak, R. M., T. Duda, A. Sitaramayya, and R. K. Sharma. "Structural and functional characterization of the rod outer segment membrane guanylate cyclase." Biochemical Journal 302, no. 2 (September 1, 1994): 455–61. http://dx.doi.org/10.1042/bj3020455.

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In the vertebrate photoreceptor cell, rod outer segment (ROS) is the site of visual signal-transduction process, and a pivotal molecule that regulates this process is cyclic GMP. Cyclic GMP controls the cationic conductance into the ROS, and light causes a decrease in the conductance by activating hydrolysis of the cyclic nucleotide. The identity of the granylate cyclase (ROS-GC) that synthesizes this pool of cyclic GMP is unknown. We now report the cloning, expression and functional characterization of a DNA from bovine retina that encodes ROS-GC.

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Faus-Llácer, Vicente, Nirmine Hamoud Kharrat, Celia Ruiz-Sánchez, Ignacio Faus-Matoses, Álvaro Zubizarreta-Macho, and Vicente Faus-Matoses. "The Effect of Taper and Apical Diameter on the Cyclic Fatigue Resistance of Rotary Endodontic Files Using an Experimental Electronic Device." Applied Sciences 11, no. 2 (January 18, 2021): 863. http://dx.doi.org/10.3390/app11020863.

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The aim of this study was to analyze the effect of the taper and apical diameter of nickel–titanium (NiTi) endodontic rotary files on the dynamic cyclic fatigue resistance. A total of 50 unused conventional NiTi wire alloy endodontic rotary instruments were used in this study. All NiTi endodontic rotary files were submitted to a custom-made dynamic cyclic fatigue device until fracture occurred. The time to failure, the number of cycles to failure, the number of pecking movements, and the length of the fractured file tip were analyzed using the analysis of variance (ANOVA) test. In addition, the Weibull characteristic strength and Weibull modulus were also calculated. The paired t-test revealed statistically significant differences between the time to failure, number of cycles to failure, and number of cycles of in-and-out movement of both the apical diameter (p ˂ 0.001) and the taper (p ˂ 0.001) of NiTi endodontic rotary files; however, the results did not show statistically significant differences between the mean length of the fractured files regarding the apical diameter (p = 0.344) and taper study groups (p = 0.344). Increased apical diameter and taper of NiTi endodontic rotary files decreased their dynamic resistance to cyclic fatigue.

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Hayakawa, N., J. Tsuji, and Y. Hamamoto. "Simultaneous Nitrogen and Phosphate Removal by the Intermittent Cyclic Process." Water Science and Technology 18, no. 7-8 (July 1, 1986): 319–26. http://dx.doi.org/10.2166/wst.1986.0304.

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By using the Intermittent Cyclic (IC) process which repeats aerobic and anaerobic conditions in an 18-m3 pilot plant reactor, domestic sewage was treated at a rate of 18 m3 per day. Operating condition was 4 cycles per day, intermittent aeration--4 hours, settling--1 hour, drawing--1 hour. Seven months of operation recorded high nitrogen removal rates: mean 86% and maximum 96%, phosphate removal rates: mean 83% and maximum 93%. Compared with conventional aerobic/anaerobic processes, the IC process, one of batch-type treatment processes, can advantageously and stably remove nitrogen and phosphate with repeated aeration and nonaeration under optimal control.

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Poręba, Marek, Waldemar Ziaja, and Jan Sieniawski. "Thermo-Chemical Process of Aluminizing of the Nickel-Base Superalloy." Materials Science Forum 674 (February 2011): 81–88. http://dx.doi.org/10.4028/www.scientific.net/msf.674.81.

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The thermo-chemical treatment routes for Renè77 superalloy were developed comprising low activity and high activity aluminizing by CVD method. The influence of the treatment on the oxidation resistance in air and creep resistance of the alloy was examined. The cyclic oxidation tests at 1100°C for 500 cycles were carried out. Creep tests were performed at 982°C at the stress level of 124 and 151.7MPa. The chemical and phase composition of the surface layer was analyzed after aluminizing. It was found that aluminide coating enhanced oxidation resistance of the Renè77 superalloy without deterioration of its mechanical properties.

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Scholze, Mario, Sarah Safavi, Maziar Ramezani, Benjamin Ondruschka, and Niels Hammer. "Fatigue Testing of Human Flexor Tendons Using a Customized 3D-Printed Clamping System." Applied Sciences 12, no. 15 (August 4, 2022): 7836. http://dx.doi.org/10.3390/app12157836.

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Improved surgical procedures and implant developments for ligament or tendon repair require an in-depth understanding of tissue load-deformation and fatigue properties. Cyclic testing will provide crucial information on the behavior of these materials under reoccurring loads and on fatigue strength. Sparse data are available describing soft tissue behavior under cyclic loading. To examine fatigue strength, a new technology was trialed deploying 3D-printing to facilitate and standardize cyclic tests aiming to determine tendon fatigue behavior. Cadaveric flexor digitorum tendons were harvested and mounted for tensile testing with no tapering being made, using 3D-printed clamps and holder arms, while ensuring a consistent testing length. Loads ranging between 200 to 510 N were applied at a frequency of 4 Hz, and cycles to failure ranged between 8 and >260,000. S–N curves (Woehler curves) were generated based on the peak stresses and cycles to failure. Power regression yielded a combined coefficient of determination of stress and cycles to failure of R2 = 0.65, while the individual coefficients for tissues of single donors ranged between R2 = 0.54 and R2 = 0.88. The here-presented results demonstrate that S–N curves of human tendons can be obtained using a standardized setting deploying 3D-printing technology.

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Putti, Venkata Siva Teja, S. Manikandan, and Kiran Kumar Ayyagari. "Effect of thermal cycling on mechanical and microstructural properties of heat-treated Ti-6Al-4V alloy." Materials Research Express 9, no. 1 (January 1, 2022): 016512. http://dx.doi.org/10.1088/2053-1591/ac487d.

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Abstract Titanium (Ti-6Al-4V) is an α+β phase-field alloy utilized in many industries due to its high strength-to-weight ratio and near-net shaping capability. Solution treated & aging, and stress relief annealing processes were performed on the samples to increase the strength and % of elongation. The heat-treated samples then thermally cycled for 500 cycles, 1000 cycles, and 1500 cycles to evaluate the microhardness and tensile properties. The presence of martensite and α 2 precipitates in the thermally cycled samples was confirmed by scanning electron microscopy (SEM) and x-ray diffraction analysis (XRD). In this investigation, at 1000 thermal cycles, all specimens show improvement in both hardness and strength when compared within the cycles. Solution-treated and aging (STA), stress relief annealing (SRA), and without any heat-treatment (WHT) processes have their highest hardness values recorded for 1000 thermal cycles, and the values are 471 HV0.5, 381 HV0.5, and 374.6HV0.5, respectively. For the SRA process, ultimate tensile strength (UTS) of 925 MPa and yield strength (YS) of 896 MPa have resulted in 1000 cycles. Similarly, at 1000 thermal cycle WHT processed samples yielded UTS of 920 MPa and YS of 885 MPa. STA process samples that are heat-treated for 1000 thermal cycles have better strength properties than SRA and WHT and had a UTS of 1530MPa and YS of 1420MPa. From a ductility point of view, a maximum elongation of 29% for the STA process has resulted. Compared to forged titanium alloy (base metal), an increase of 31% elongation and 41% ultimate tensile strength for solution treated and aging process at 1000 cycles has resulted in this investigation.

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Lüders, Caroline, and Michael Sinapius. "Fatigue of fibre-reinforced plastics due to cryogenic thermal cycling." Journal of Composite Materials 53, no. 20 (January 31, 2019): 2849–61. http://dx.doi.org/10.1177/0021998319826359.

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Due to the different thermal expansion of the constituent materials, cyclic thermal loading of fibre reinforced plastics induces alternating stresses in the material at two scales: (1) at the microscale (level of fibre–matrix-interaction) and (2) at the macroscale (level of the multidirectional laminate). Especially the effect of the thermal-induced stresses at the microscale is not comprehensively investigated yet. In the present paper, the effects of both scales are analysed. For the investigation of the microscale effect, unidirectional laminates are thermally cycled between 293 K and 90 K up to 1000 times. Afterwards, by mechanical tests at room temperature, the elasticity and strength properties in the different material directions are determined as function of the number of thermal cycles. Additionally, thermally cycled specimens are microscopically investigated in order to observe the matrix crack forming process at thermal fatigue loading. Contrary to the expectations, no significant matrix cracking and therefore no significant reduction of the elasticity and strength properties due to the thermal cycling are observed. In order to analyse the effect of the superposition of the thermal-induced stresses on micro- and macroscale, cross-ply laminates are investigated in the same manner. In these laminates matrix cracks are detected after 1000 cycles, which, however, do not reduce the stiffness and strength of the cross-ply laminates.

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Jiang, Yu, Meilian Liang, Yanmei Teng, and Xiaodong Xu. "The Cyclic Triangle-Free Process." Symmetry 11, no. 8 (July 29, 2019): 955. http://dx.doi.org/10.3390/sym11080955.

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For positive integers s and t, the Ramsey number R ( s , t ) is the smallest positive integer n such that every graph of order n contains either a clique of order s or an independent set of order t. The triangle-free process begins with an empty graph of order n, and iteratively adds edges chosen uniformly at random subject to the constraint that no triangle is formed. It has been an important tool in studying the asymptotic lower bound for R ( 3 , t ) . Cyclic graphs are vertex-transitive. The symmetry of cyclic graphs makes it easier to compute their independent numbers than related general graphs. In this paper, the cyclic triangle-free process is studied. The sizes of the parameter sets and the independence numbers of the graphs obtained by the cyclic triangle-free process are studied. Lower bounds on R ( 3 , t ) for small t’s are computed, and R ( 3 , 35 ) ≥ 237 , R ( 3 , 36 ) ≥ 244 , R ( 3 , 37 ) ≥ 255 , R ( 3 , 38 ) ≥ 267 , etc. are obtained based on the graphs obtained by the cyclic triangle-free process. Finally, some problems on the cyclic triangle-free process and R ( 3 , t ) are proposed.

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Halford, Martin. "Process control and long cycles." Production Engineer 65, no. 9 (1986): 24. http://dx.doi.org/10.1049/tpe.1986.0211.

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Helmers, Roelof, and I. Wayan Mangku. "Predicting a cyclic Poisson process." Annals of the Institute of Statistical Mathematics 64, no. 6 (March 17, 2012): 1261–79. http://dx.doi.org/10.1007/s10463-012-0349-x.

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Hansen, Jens Erik, and Sten Bay Jørgensen. "Control of Forced Cyclic Process." IFAC Proceedings Volumes 28, no. 9 (June 1995): 21–26. http://dx.doi.org/10.1016/s1474-6670(17)47010-8.

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Zhao, X. C., Y. D. Zhang, and Y. J. Ma. "Finite Element Analysis of Vibratory Stress Relief Process." Applied Mechanics and Materials 88-89 (August 2011): 623–27. http://dx.doi.org/10.4028/www.scientific.net/amm.88-89.623.

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The process of stress vibratory relief is gaining more and more weight as manufacturing process. This is mainly due to the fact that vibratory stress relief has the advantage of low energy consumption and dramatic reduction of pollution to the environment in respect to traditional thermal stress relief process. A finite element model is developed for the simulation of vibration stress relief (VSR) process. A cantilever beam was pre-stressed and then subjected to transverse cyclic force to see the effect of vibration frequency, time and amplitude on the reduction of residual stress. It was shown that the excitation frequency and amplitude of the load on the beam had great effect on the reduction of the residual stress. Increasing vibration time can decrease the magnitude of residual stress, but its influence reduces greatly after several cycles.

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Kampf, Rudolf, Marek Potkány, Lucia Krajčírová, and Katarína Marcineková. "Kalkulacija troška životnog ciklusa i njegova važnost u procesu nabavke vozila za prijevoz kamiona." Naše more 63, no. 3 (June 2016): 129–33. http://dx.doi.org/10.17818/nm/2016/si10.

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Goto, Sachiko, Toshinori Maruyama, Yoshiharu Azuma, Yoshitada Nakagiri, Katsuhiko Sugita, and Akira Yoshida. "302 Effect of Extended-cycle Processing on Mammographic Films." Japanese Journal of Radiological Technology 53, no. 8 (1997): 1174. http://dx.doi.org/10.6009/jjrt.kj00001356145.

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Pietrzak, Magdalena. "Cyclical changes in deformation process in granular material in active state." E3S Web of Conferences 92 (2019): 17004. http://dx.doi.org/10.1051/e3sconf/20199217004.

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This paper presents a detailed study of a selected small scale model test, performed on a sample of surrogate granular material, retained by a rigid wall (typical geotechnical problem of earth thrust on a retaining wall). The experimental data presented in this paper show that the deformation of granular sample behind retaining wall can undergo some cyclic changes. The nature of these cycles is not clear – it is probably related to some micromechanical features of granular materials, which are recently extensively studied in many research centers in the world. Employing very precise DIC (PIV) method can help to relate micro and macro-scale behavior of granular materials.

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Liu, Enlong, Yuanming Lai, Mengke Liao, Xingyan Liu, and Feng Hou. "Fatigue and damage properties of frozen silty sand samples subjected to cyclic triaxial loading." Canadian Geotechnical Journal 53, no. 12 (December 2016): 1939–51. http://dx.doi.org/10.1139/cgj-2016-0152.

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Cyclic triaxial tests were conducted to explore the influences of dynamic axial loading on the dynamic features and fatigue of frozen silty sand, using an MTS-810 apparatus from Material Testing Systems (MTS). The temperature was −15 °C, and the cyclic axial loads with different amplitudes at 1.0 Hz were applied under confining pressures of 0.6, 1.4, and 6.0 MPa. The cyclic triaxial test results demonstrate that the residual axial strain of the frozen silty sand samples increases gradually during the initial cycles and then increases with increasing number of cycles at a constant speed until failure. The residual volumetric strain contracts during the initial loading cycles and then dilates until failure. Both the residual strain method and the residual volumetric strain method proposed here can be used to describe the degradation process in frozen silty sand samples subjected to cyclic loading. The dynamic axial stiffness of a frozen sample decreases rapidly in the initial cycles and then approaches a stable value with increasing cycle number. The initial damage increases when the stress ratio increases; the larger the stress ratio, the smaller the number of cycles at failure.

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32

Kosai, Koji, Yugang Zhao, and Jiwang Yan. "Crack Propagation Behavior of Fused Silica during Cyclic Indentation under Incremental Loads." Applied Sciences 12, no. 13 (June 29, 2022): 6589. http://dx.doi.org/10.3390/app12136589.

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Fused silica is an important optical material with important applications, where the surface must be precisely machined without subsurface damage. In this study, multi-cyclic indentations under incremental loads were performed on fused silica using two kinds of indenters to clarify the mechanisms of crack generation and propagation induced by precision grinding. It was found that incremental loading cyclic nanoindentation induced various patterns of subsurface cracking and surface spalling. Four kinds of surface spalling were identified at different locations around an indent, the temporal formation mechanisms of which were clarified by microscopic observation and topographical measurement. Load–displacement curve analysis demonstrated that incremental propagation of lateral cracks during early indentation cycles caused large-scale brittle fractures during later cycles. Compared with a Berkovich indenter, a cube-corner indenter caused more significant brittle fractures and surface spalling. The findings in this study will deepen the understanding of subsurface damaging mechanism of fused silica and other brittle solids caused by cyclic tool-workpiece interactions in grinding and other mechanical machining processes.

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Lechowicz, Jaromir B. "Modeling of alternating copolymerization of cyclic anhydrides with epoxides." Polimery 64, no. 04 (2019): 252–58. http://dx.doi.org/10.14314/polimery.2019.4.2.

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34

Parimin, Noraziana, and Esah Hamzah. "Oxidation Kinetic and Oxide Scale Morphology of Fe-33Ni-19Cr Ni-Based Superalloy." Solid State Phenomena 336 (August 30, 2022): 3–9. http://dx.doi.org/10.4028/p-j0a5a5.

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In the present study, outcome of various grain size of heat treated Fe-33Ni-19Cr Ni-based superalloy at high temperature cyclic oxidation condition was investigated. The Fe-33Ni-19Cr Ni-based superalloy was experienced a series of heat treatment process at two assorted temperatures, which are 1000 °C and 1100 °C, soaking for 3 hours and then rapid cooled by water quench. The heat treatment process produced a fine and coarse grain size structure. The cyclic oxidation test was performed for both heat treated samples at 700 °C under cyclic conditions in the laboratory air for 150 cycles. The weight change was measured discontinuously at different cycles to identify the kinetics of oxidation. SEM and FESEM outfitted with EDX spectrometer were utilized to analyzed the oxidation product. As a result, the weight change increased with time, with fine grain HT1000 sample recorded lower weight gain compared to coarse grain HT1100 sample. In addition, both sample formed uniform and continuous oxide scale on the alloy surface.

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35

Ali Laftah Abbas. "NON-LINEAR ANALYSIS OF CONTINUOUS COMPOSITE CONCRETE–STEEL BEAMS UNDER CYCLIC LOADINGS." Diyala Journal of Engineering Sciences 4, no. 1 (June 1, 2011): 125–43. http://dx.doi.org/10.24237/djes.2011.04109.

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Non-linear analysis of continuous composite concrete–steel beams under cyclic loadings has been investigated in this paper. A three-dimensional finite element analysis (FE) ANSYS computer program(ANSYS version 9.0) was conducted to investigate the nonlinear behaviour of this beam up to failure through the prediction of the values of slip, deflection along the spans of the composite beam for different number of loading cycles up to one million cycles of the load of range (52%of the ultimate load of the beam). The results obtained from analyzing a continuous composite concrete-steel beam under cyclic loadings show good agreement with available experimental results and other available analytical results. A parametric study is also conducted in this paper to study the influence of some parameters such as the number of loading cycles, and the amount of load ratio on the values of slip and deflection. This parametric study shows that as the number of loading cycles increased, slip and deflection values along the composite beam will increased due to reduction in strength of all components of the composite beam, and the absolute values of maximum slip and maximum deflection will reduce as the load ratio changes from negative to positive signs .

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36

A.M., Suranto, Eko Widi Pramudiohadi, and Anisa Novia Risky. "Optimization of Cyclic Steam Stimulation Process Using Response Surface Methodology." Journal of Petroleum and Geothermal Technology 2, no. 1 (May 28, 2021): 26. http://dx.doi.org/10.31315/jpgt.v2i1.4684.

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Heavy oil has characteristics such as API gravity 10-20 and high viscosity (100-10,000 cp) at reservoir temperature. Several methods have been successfully applied to produce these reserves, such as cyclic steam stimulation (CSS). Cyclic steam stimulation is a thermal injection method that aims to heat the oil around production wells. This paper presents the investigation regarding CSS application in heavy oil using Response Surface Methodology. Several scenarios were done by varying the operating conditions to obtain the most realistic results and also evaluating the factors that most influence the success of CSS process. Optimization is performed to find the maximum recovery factor (RF) value and minimum steam oil cumulative ratio (CSOR). The operating parameters used are CSS cycle, steam injection rate, and steam quality. Then statistical modeling is carried out to test the most important parameters affecting RF and CSOR for 10 years. The simulation results show that the CSS cycle, steam injection rate, and steam quality affect the RF and CSOR. The maximum RF results with the minimum CSOR were obtained at 39 cycles, an injection rate of 300 bbl/day, and a steam quality of 0.9 with an RF and CSOR value is 24.102% and 3.5129 respectively.

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37

Shin, Jae Sun, Sung Jin Cho, Suk Hoon Choi, Faraz Qasim, Heung N. Lee, Jae Ho Park, Won Jae Lee, Euy Soo Lee, and Sang Jin Park. "A Simulation Study of Inter Heat Exchanger Process in SI Cycle Process for Hydrogen Production." Korean Chemical Engineering Research 52, no. 4 (August 1, 2014): 459–66. http://dx.doi.org/10.9713/kcer.2014.52.4.459.

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Fu, Zunan, Guoshuai Wang, Wenbo Song, Yanming Yu, Pengfei Wei, and Tingyu Wu. "Deformation Behavior of Saturated Soft Clay under Cyclic Loading with Principal Stress Rotation." Applied Sciences 11, no. 19 (September 27, 2021): 8987. http://dx.doi.org/10.3390/app11198987.

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Under long-term traffic loading, the soil elements in subgrade are subjected to continuous principal stress rotation. In order to study the deformation properties of soft clays under traffic loading with principal stress rotation, a series of cyclic torsional shear tests were conducted on Wenzhou soft clays under different torsional cyclic stress ratios and degrees of principal stress rotation. The test results showed the stiffness softening of soil under long-term traffic loading. In addition, the principal stress rotation induced by traffic loading aggravated the deformation of clay samples and pore pressure accumulation. A modified dynamic pore pressure model was applied to consider the effect of principal stress rotation on undrained cumulative pore pressure, predicting the growth of cumulative pore pressure at different cycles. Considering loading cycles and the principal stress rotation, a modified Hardin–Drnevich (H-D) backbone curve model under traffic loading with principal stress rotation was proposed, and the predictive values of this model agreed well with the experimental values. Compared with the traditional H–D model, this model better reflects the cyclic deformation of soft clays under long-term traffic loading with principal stress rotation.

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Yang, Xi, He Jun Li, and Kua Hai Yu. "Effects of Bending Cyclic Load on Mechanical Properties of 2D Carbon Cloth Laminated C/C Composites." Applied Mechanics and Materials 157-158 (February 2012): 792–95. http://dx.doi.org/10.4028/www.scientific.net/amm.157-158.792.

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Bending cyclic fatigue tests of 2D laminated C/C composites were conducted under load control at a sinusoidal frequency of 10 Hz. And three-point bending tests of fatigued specimens with various cycles were conducted at room temperature to evaluate the effects of cyclic load on mechanical properties. 2D C/C specimens were prepared by an isothermal chemical vapor deposition (CVD) process. The mechanical properties of composites were improved after cyclic loading at most the flexural strength by about 46% and the modulus 38%. The results show that the flexural properties of C/C composites were enhanced with the increase in fatigue cycles. It is suggested that the weakened interface between matrix and fibers by cyclic load play important roles in enhancing the property of C/C composites.

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40

Kim, Soongoo, and Younghee Kim. "하수처리공법의 잠재적 환경영향 분석을 위한 전과정 평가지수의 기여도 평가." Journal of the Korean Society of Urban Environment 18, no. 3 (September 30, 2018): 271–78. http://dx.doi.org/10.33768/ksue.2018.18.3.271.

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41

Leahy, J. C., K. J. Mathias, A. Heaton, D. E. T. Shepherd, D. W. L. Hukins, W. F. Deans, M. W. Brian, and D. Wardlaw. "Design of spinous process hooks for flexible fixation of the lumbar spine." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 214, no. 5 (May 1, 2000): 479–87. http://dx.doi.org/10.1243/0954411001535507.

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A prototype flexible fixation system for the lumbar spine was subjected to tensile testing to failure and cyclic tensile testing in order to determine any regions of weakness. The system consisted of a spinous process hook and two laminar hooks made of stainless steel (316L). Each laminar hook was attached to the spinous process hook by a loop of polyester braid secured by a crimped metal sleeve. In five tensile tests, the system failed by irreversible deformation of the spinous process hook at 2.5 ° 0.3 kN (mean ° standard deviation). In three cyclic tests, in which the applied tension varied sinusoidally between 0.04 and 0.4 kN at a frequency of 5 Hz, failure occurred after less than 400000 loading cycles. This occurred as a result of fatigue crack initiation and propagation in the spinous process hook. A finite element model showed a stress concentration in the region where the crack occurred, which raised the applied stress above the tensile fatigue strength of this stainless steel. The spinous process hook was redesigned for manufacture in a titanium alloy (Ti-6Al-4V ELI) to minimize artefacts in magnetic resonance imaging. Further finite element models showed no unacceptable stress concentrations.

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42

da Costa, JA, A. Akhavan-Safar, EAS Marques, RJC Carbas, and LFM da Silva. "Effects of cyclic ageing on the tensile properties and diffusion coefficients of an epoxy-based adhesive." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 235, no. 6 (February 15, 2021): 1451–60. http://dx.doi.org/10.1177/1464420721994871.

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In real practice, adhesively bonded structures are usually exposed to cyclic environmental conditions. However, cyclic ageing processes are relatively unexplored. The aim of this study is to consider the effect of cyclic ageing on the rate of water uptake and the drying process in an epoxy-based adhesive. Fick’s law was considered to estimate the water diffusion coefficients for the ageing and the drying steps at different cycles. Different cyclic ageing times have been considered in the ageing procedure. Dogbone shape specimens were also manufactured and subjected to cyclic aging to investigate the tensile properties of the tested adhesive as a function of aging cycles. The gravimetric results showed that the rate of water uptake and drying is mainly a function of the level of water uptake of the first ageing cycle. Tensile test results showed that the maximum water content increases with each subsequent ageing cycle. It was also found that the Young’s modulus and the tensile strength of the adhesive decreased significantly after the initial ageing cycle, but all subsequent ageing cycles have considerably less influence on the mechanical properties of the adhesive.

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43

Zhao, Sheng Li, Ji Ne Zhu, and Zhao Yang Wu. "Nanocrystalline NiO Thin Film Prepared by Sol-Gel Process." Advanced Materials Research 150-151 (October 2010): 1073–76. http://dx.doi.org/10.4028/www.scientific.net/amr.150-151.1073.

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The NiO thin film was deposited on the stainless and single crystal Si substrate by the dip-coating combined with thermal treatment. Thermal decomposition behavior of gel precursor, the structure, morphology and electrochemical properties of NiO thin film were characterized by TG-DSC, XRD, SEM, cyclic voltammetry and the constant current charge/discharge technology. The results show that the gel completely decomposes at 430°C to form the nanocrystalline NiO gradually and its crystal structure becomes integrity and particles largen as the increasing of the sintering temperature. The NiO film sintered at 600°C exhibits smooth surface, uniform, compact and free of cracks. At the cut-off voltage of 0-3V and the current density of 0.01 mA/cm2, its first discharge special capacity is 1285mAh/g and remains 650mAh/g after 300 cycles. In addition, the special capacity of NiO thin film still remains above 300mAh/g at large current density of 0.04 mAh/g after 300cycles exhibiting excellent electrochemical performance.

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44

Farfel, Z., E. Friedman, and E. Hanski. "The invasive adenylate cyclase of Bordetella pertussis. Intracellular localization and kinetics of penetration into various cells." Biochemical Journal 243, no. 1 (April 1, 1987): 153–58. http://dx.doi.org/10.1042/bj2430153.

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The penetration of Bordetella pertussis adenylate cyclase into various mammalian cells exhibits similar kinetics; the accumulation of both intracellular cyclase activity and cyclic AMP is rapid, reaching constant levels after 15-60 min of incubation. The kinetics of enzyme penetration into turkey erythrocytes is different; cyclase activity and cyclic AMP accumulate linearly and do not reach constant levels even after 6 h of incubation. In the preceding paper [Friedman, Farfel & Hanski (1987) Biochem. J. 243, 145-151] we have suggested that the constant level of intracellular cyclase activity reflects a steady state formed by continuous penetration and intracellular inactivation of the enzyme. In contrast with other mammalian cells, no inactivation of cyclase is observed in turkey erythrocytes. These results further support the notion that there is continuous penetration and deactivation of the invasive enzyme in mammalian cells. A 5-6-fold increase in specific activity of the invasive cyclase is detected in a pellet fraction of human lymphocytes in which a similar increase in specific activity of the plasma-membrane marker 5′-nucleotidase is observed. A similar increase in the invasive-cyclase specific activity is detected in a membrane fraction of human erythrocytes. Cyclase activity in a membrane-enriched fraction of human lymphocytes reached a constant level after 20 min of cell exposure to the enzyme. Similar time courses were observed for accumulation of cyclase activity and cyclic AMP in whole lymphocytes [Friedman, Farfel & Hanski (1987) Biochem, J. 243, 145-151]. We suggest therefore that cyclic AMP generation by the invasive enzyme as well as the intracellular inactivation process occur while it is associated with a membrane fraction identical, or closely associated, with the plasma membrane.

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45

Yura, K. "A Revised Cyclic Production Method." Journal of Engineering for Industry 113, no. 3 (August 1, 1991): 328–34. http://dx.doi.org/10.1115/1.2899704.

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The objective of the cyclic scheduling is the minimization of the job output interval between cycles from a manufacturing system in a steady state. A revised cyclic production method was developed to minimize the job output interval. The job output interval was obtained by analyzing the workflow network and the process network. An optimum scheduling procedure was constructed and a numerical example was presented.

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46

Heard, Gerald. "IS DISCOVERY ITSELF A CYCLIC PROCESS?*." Annals of the New York Academy of Sciences 117, no. 1 (December 16, 2006): 636–46. http://dx.doi.org/10.1111/j.1749-6632.1964.tb48217.x.

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47

Jaworski, Jerzy, and Tomasz Łuczak. "Cycles in a Uniform Graph Process." Combinatorics, Probability and Computing 1, no. 3 (September 1992): 223–39. http://dx.doi.org/10.1017/s0963548300000262.

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We study the asymptotic properties of a “uniform” random graph process in which the minimum degree of U(n, M) grows at least as fast as ⌊M/n⌋. We show that if M — n → → ∞, almost surely U(n, M) consists of one giant component and some number of small unicyclic components. We go on to study the distribution of cycles in unicyclic components as they emerge at the beginning of the process and disappear when captured by the giant one.

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48

Testarelli, L., N. M. Grande, G. Plotino, M. Lendini, G. Pongione, G. De Paolis, F. Rizzo, V. Milana, and G. Gambarini. "Cyclic Fatigue of Different Nickel-Titanium Rotary Instruments: A Comparative Study." Open Dentistry Journal 3, no. 1 (April 16, 2009): 55–58. http://dx.doi.org/10.2174/1874210600903010055.

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Since the introduction of nickel-titanium alloy to endodontics, there have been many changes in instrument design, but no significant improvements in the raw material properties, or enhancements in the manufacturing process. Recently, a new method to produce nickel-titanium rotary (NTR) instruments has been developed, in an attempt to obtain instruments that are more flexible and resistant to fatigue. NTR instruments produced using the process of twisting (TF, SybronEndo, Orange, CA) were compared to NTR instruments from different manufacturers produced by a traditional grinding process. The aim of the study was to investigate whether cyclic fatigue resistance is increased for TF NTR files. Tests were performed with a cyclic fatigue device that evaluated cycles to failure of rotary instruments inside curved artificial canals. Results indicated that size 06-25 TF instruments showed a significant increase (P< .05). In the mean number of cycles to failurewhen compared to the other tested 06-25 NTR. Hence, it can be concluded that size 06-25 TF NTR instruments were found to be significantly more resistant to fatigue than those produced with the traditional grinding process.

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49

Liu, Furong, Zhiwei Zhou, Wei Ma, Shujuan Zhang, and Zhizhong Sun. "Dynamic Parameters and Hysteresis Loop Characteristics of Frozen Silt Clay under Different Cyclic Stress Paths." Advances in Materials Science and Engineering 2021 (June 8, 2021): 1–22. http://dx.doi.org/10.1155/2021/3763181.

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In cold regions, the long-term stability of engineering facilities is unavoidably influenced by the negative temperature, freeze-thaw process, dry-wet process, and dynamic loading conditions induced by earthquakes and traffic loads. In order to investigate the effects of different cyclic stress paths on the evolution of dynamic mechanical properties of frozen silt clay, a series of cyclic triaxial tests with variation confining pressure (VCP) or constant confining pressure (CCP) were performed. Triaxial low-temperature apparatus (MTS-810) was taken advantage of to simulating various cyclic stress paths by changing cyclic loading conditions of axial stress and confining pressure. In this paper, the evolution features of the axial resilient modulus, damping ratios, and the shape of hysteresis loops with an increase in the number of load cycles under different dynamic stress paths are comprehensively studied. The results show that the loading angle of cyclic stress path and the phase difference between cyclic axial stress and confining pressure are the main factors that remarkably affect the development characteristics of the resilient modulus and damping ratio. With increasing of the loading angle and phase difference, the resilient modulus increases, but damping ratio increases with increasing of loading angle and with decreasing of phase difference. With the continuous increase in the number of loading cycles, the samples of frozen soil show compacting and hardening characteristics. With an increase in the number of load cycles, the shape of hysteresis loop becoming narrows, the resilient modulus decreases at the initial stage and then gradually increases, and the damping ratio stably decreases. According to contrastively analyzing the evolution of dynamic parameters and the shape features of hysteresis loops under various cyclic stress paths, it can be clearly discovered that the evolution of sample microstructure and the development of dynamic characteristics of frozen samples have obvious dependence on the cyclic stress path. Therefore, the effects of variable confining pressure (VCP) on dynamic behaviors of frozen soils are nonnegligible in practical cold region engineering.

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Aprilia, Annisa, Vika Marcelina, Fitri Yuliasari, Yeni Wahyuni Hartati, Fitrilawati, Lusi Safriani, and Rustam E. Siregar. "Study of Electrochemical Deposition Process of Graphene Oxide on DSSC TiO₂ Based Photoanode." Materials Science Forum 966 (August 2019): 378–85. http://dx.doi.org/10.4028/www.scientific.net/msf.966.378.

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Graphene oxide (GO) layer has been successfully deposited on to ITO/TiO2 substrate by electrochemical deposition. Deposition process of GO layers were carried out in one, three, and six cycles in the voltage range of-1.6 to 0 volt and scan rate of 50 mV/s. The variation of cycles was performed, in order to study the deposition process relates to device performances. TiO2 macro-channel (TiO2μc) also introduced in photoanode system and it required annealing treatment up to 500°C. The oxygen content in GO will be reduced by annealing treatment and the reduced-GO (rGO) layer was trapped inside of TiO2 mesoporous. The cyclic voltammetry curves of blank sample and GO deposition were also observed in order to ensure the GO deposition process was successfully done. After immersing in ruthenium dye overnight, the ITO/TiO2/rGO/TiO2-μc was sandwiched with Pt/FTO as counter electrode to configure dye sensitized solar cell (DSSC) structure. The photovoltaic characteristics, morphology, and UV-Vis absorbance of each layer were investigated. A highest DSSC efficiency (η= 3.34 %) was achieved by 3-cycles of GO deposition process of photoanode with photocurrent density (Jsc) of 9.94 mA/cm2, open voltage (Voc) of 0.70 V and fill factor (FF) of 48.69% under 100 mW/cm2 of light irradiation.

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Journal articles on the topic 'Cyclar process'

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