Auxiliary Component Research Articles

Numerical and experimental study on gas-water separators for a PEMFC system

ABSTRACT The gas-water separator is an important auxiliary component of the hydrogen recirculation subsystem for the proton exchange membrane fuel cell (PEMFC) system. This study investigated three baffle separators with different structures used for a 75 kW PEMFC system by computational fluid dynamics (CFD) simulation and experimental validation. An Euler-Lagrange two-phase simulation model was established to investigate the gas-phase flow characteristics and the droplets trajectory and film distribution in separators. Moreover, an experimental bench was set up to test the overall performance of the separators. The results showed that the CFD model can predict the performance of the gas-water separator accurately. Through the comparison of air and mixed hydrogen, it was found that the density of the gas phase fluid has a great influence on the pressure drop. The local gas flow at the baffle bottom where the film fall directly is at high velocity in separator A, resulting in that the liquid film is broken easily to cause more fine droplets being entrained again into the outflow. Besides, thicker liquid film still formed in the top part of the separators A and B compared with separator C, which is not conducive for high separation performance. Thus, the separator C is preferred to be suggested for PEMFC systems.

Inclusion complexes of imidazolium carboxylate-metal species in the water-soluble sulfonated calix[4]arene system

Two multi-component crystal structures comprising a carboxylic acid-functionalized imidazolium zwitterion, a p-sulfonatocalix[4]arene anion and aquated metal ion (Na+ or Y3+) with or without an auxiliary component (the 3-methoxyphenyl-triphenylphosphonium cation) are reported. The carboxylic acid-functionalized imidazolium ion binds either as a monodentate or a bidentate ligand depending on the nature of the metal ions, and a bi-layer arrangement prevails in the extended structure regardless of the type of metal ion employed or presence/lack of auxiliary component.

Development of dumbbell-shaped La2Si2O7:Eu3+ nanocrystalline phosphors for solid-state lighting applications

There are ongoing efforts to develop novel phosphors with the properties required to make an object look as natural as it does under sunlight. It has been proven that particle morphology influences the luminescent properties of a phosphor. The rare-earth pyrosilicates, such as La2Si2O7 (LSO) are currently regarded as novel promising scintillators and protective pigments because of their good chemical and thermal stabilities. However, to date, there have been no reports available on the definite morphology of the LSO matrix and the precise luminescent properties of the trivalent europium (Eu3+)-doped LSO phosphor. Herein, we report the development of Eu3+-activated dumbbell-shaped LSO nanocrystalline phosphors using a two-step solvothermal and hydrothermal approach. After regrowth, the amorphous natured LSO:Eu3+ precursor was transformed into well-defined LSO:Eu3+ dumbbell-shaped nanocrystalline phosphors (LSO-R:Eu3+) with a pure monoclinic phase. The phase purity was verified by Rietveld refinement analysis. The formation mechanism of the dumbbell-shaped particles was evaluated using surface morphological studies, and the involvement of the crystal splitting mechanism was established. The luminescence spectra revealed robust red emission at 614 nm under ultraviolet (UV) and near-UV excitations. The dipole-dipole interactions between the neighboring Eu3+ ions induced the concentration quenching in LSO host matrix. Chromaticity coordinates (0.645, 0.342) emerged in the reddish-orange region and were comparable to the standard-definition and high-definition digital television coordinates (0.640, 0.330). Therefore, these results indicate that the synthesized LSO-R:Eu3+ dumbbell-shaped nanocrystalline phosphor is a promising auxiliary red component for assembling desired white light-emitting diodes for indoor illuminations.

«Электронный язык» на основе модифицированных полиариленфталидами электродов для распознавания модельных растворов триптофана

The effect of auxiliary substances in the composition of the dosage form (sucrose, lactose, talc and starch) on the voltammetric registration of tryptophan using two- and threesensor systems such as "electronic tongue" based on glassy carbon electrodes modified with polyarylenephthalides was studied. For the subsequent chemometric processing of the obtained data, the principal component analysis and soft independent modeling of class analogies were used. It has been shown that electrodes modified with various polyarylenephthalides have cross-sensitivity to four model solutions of tryptophan, each of which contains a certain auxiliary component. When the modified electrodes are used separately, the analyzed model solutions of tryptophan form clusters on the score plots of PCA that intersect with each other, which does not allow them to be reliably recognized. However, the combination of modified electrodes into two- and three-sensor systems due to cross-sensitivity makes it possible to obtain the PCA score plots, in which clusters of samples of model solutions of tryptophan intersect less or do not intersect at all, and, therefore, to recognize them with a high probability. In almost all cases of using two- and three-sensor systems, the classification sensitivity is 100%. When using modified electrodes separately, the specificity of the classification varies from 20 to 100%, when using two-sensor systems – from 50 to 100%. The specificity of the classification when using a three-sensor system is not less than 90%. The proposed sensor system, after additional studies, can be used to recognize medicines containing the same active substance, but different auxiliary components, and will also allow detecting the presence of impurities in medicines.

Synergism of uncoupler dicoumarin and nonmetallic mineral tourmaline for the sewage sludge treatment process: Reducing sludge generation

Environmental concerns linked to the recycling of sewage sludge on land involve the hazard of nutrient leaching, impacts on soil biodiversity and greenhouse gas emissions. Sludge reduction in a wastewater treatment plant has recently received considerable attention worldwide. Large amounts of excess sludge needs to be disposed of in a cost-effective and environmentally friendly manner. In this study, dicoumarin was used as a metabolic uncoupler, its effect on the sludge reduction, effluent quality and sludge performance at the low concentration range (≤10 ​mg/L) and at high concentration (40 ​mg/L) in the sequencing batch reactor (SBR) system was investigated. It showed that Yobs was decreased with high dicoumarin concentration. Chemical oxygen demand (COD) and total nitrogen (TN) removal efficiency are also decreased while the sludge activity was enhanced. Tourmaline, a low cost natural nonmetallic mineral with unique physical properties and a promising environmental material could improve the negative effects caused by high concentration of dicoumarin without increasing the sludge yield in the SBR system. Synergistic effect of tourmaline with high concentration dicoumarin showed COD and TN removal efficiency increase. Yobs value was 0.13. The decrease in nitrite accumulation and increase in microbial activity may correlate to the existence of electrostatic fields and far infrared rays generated by tourmaline. Tourmaline also improved the sludge settling performance due to its adsorption characteristics. Effect of optimum environmental conditions; pH (6.5 ​± ​0.3, 7.5 ​± ​0.3, and 8.5 ​± ​0.3), temperature (15 ​°C, 25 ​°C, and 35 ​°C) and other factors on the synergistic action of dicoumarin and tourmaline was also studied. It is recommended to use dicoumarin as the main component and tourmaline as the auxiliary component. The synergistic effect of the two can solve the negative impact caused by the uncoupling agent administration alone.

Identification and characterization of a novel AA9-type lytic polysaccharide monooxygenase from a bagasse metagenome.

Lytic polysaccharide monooxygenases (LPMOs) are auxiliary enzymes catalyzing oxidative cleavages of cellulose chains in crystalline regions, resulting in their increasing accessibility to the hydrolytic enzyme counterparts and hence higher released sugars from biomass saccharification. In this study, a novel auxiliary protein family 9 LPMO (BgAA9) was identified from a metagenomic library derived from a thermophilic microbial community in bagasse collection site where diverse AA9 and AA10 putative sequences were annotated. The enzyme showed highest similarity to a glycoside hydrolase family 61 from Chaetomium thermophilum. Recombinant BgAA9 expressed in Pichia pastoris cleaved cellohexaose (DP6) into shorter cellooligosaccharides (DP2, DP3, and DP4). Supplementation BgAA9 to a commercial cellulase, Accellerase® 1500 showed strong synergistic effect on saccharification of Avicel® PH101, decrystallized cellulose, filter paper, and alkaline-pretreated sugarcane bagasse, resulting in 63-93% increase in the total reducing sugar yield after incubation at 50 °C for 72 h. Strong synergism was shown between BgAA9 and the cellulase with the highest total fermentable sugar yield obtained from 75:25% of Accellerase®1500:BgAA9 which released 39 mg glucose/FPU (filter paper unit) equivalent to 38.7% higher than Accellerase®1500 alone at the same total protein dosage of 5 mg/g substrate according to the mixture design study. The enzyme represented the first characterized LPMO from environmental metagenome and a potent auxiliary component for biomass saccharification. KEY POINTS: • BgAA9 represents the first characterized LPMO from metagenome. • 12 AA families were annotated in thermophilic bagasse fosmid library by NGS. • BgAA9 showed homology to Cel61 in Chaetomium thermophilum. • BgAA9 oxidized cellohexaose and PASC to DP2, DP4, and DP6. • BgAA9 showed strong synergism to Accellerase on bagasse hydrolysis.

Latissimus Dorsi-lumbar Artery Perforator Chimeric Flap with Intra-flap Crossover Anastomosis for Breast Reconstruction.

Latissimus dorsi (LD) flaps are widely used in breast reconstruction for their ease of use and minimal sacrifice of the donor site. Various strategies to increase flap volume have been suggested, but tissue volume is often insufficient for patients with little subcutaneous fat. While lumbar artery perforator (LAP) flaps are advantageous for thin patients because they allow for the addition of a large amount of fat, the vascular pedicle is short and vascular grafts are often required. To address these shortcomings, we propose here a LD-LAP chimeric flap. Specifically, the LD flap and LAP flap are elevated as one piece, and the 6th or 7th intercostal artery perforators and lumbar artery perforators, which are harvested together with the flap, are connected via intra-flap crossover anastomosis. Anastomosis for both intercostal artery perforators and lumbar artery perforators was performed about 1 cm away from the flap. Indocyanine green angiography performed after anastomosis showed improved blood flow to the LAP flap portion of the chimeric flap. The chimeric flap was used in 4 patients, with a mean flap volume of 460 ml (range, 300-690 ml) and mean duration of 439 minutes (393-484 minutes) for reconstruction surgery. During the mean follow-up period of 29.5 months (range, 16-40 months), sufficient tissue volume was obtained and none of the patients developed flap necrosis. Although our method requires vascular anastomosis and may extend operative time, it substantially increases LD flap volume and thus is likely to be an effective auxiliary component to breast reconstruction using LD flaps.

Determination of the fatty acids composition of refined sunflower oil and possibility of its changing during storage period

Refined sunflower oil is an auxiliary component of many dosage forms made in pharmacy. For their preparation, pharmacies purchase oils from different manufacturers and have the right to use it throughout the shelf life. However, the question arises of maintaining the stability of the fatty acid composition of the oil because of the influence of various environmental factors. In previous studies, the authors investigated the change in the composition of basic fatty acids (FA) of sunflower oil during heating or long-term storage, but there are no studies of the full FA composition of sunflower oil, as well as an assessment of its dependence on the period of the oil using. The aim. Detailed study of the FA composition of refined sunflower oil from different manufacturers, assessment of the effect of the shelf life of the oil on its FA composition and its compliance with the requirements of the European Pharmacopoeia (EP). Materials and methods. The determination of the FA composition of seven samples of refined sunflower oil was carried out by gas chromatography with a flame ionization detector using the Rt-2560 column (100 m×0.25 mm×0.20 µm). Results. The analysis of seven samples of refined sunflower oil showed the presence of 24 FA in most of them. Polyunsaturated FA predominate among them with a percentage of 52.45-60.86 %. The value of the fatty acids percentage in each groups (saturated, mono- and polyunsaturated fatty acids) are quite similar regardless of the oil shelf life at the time of the research. All test samples, except one, by the percentage content of the main FA correspond to EP requirements. The results of the quantitative content of the main FA of sunflower oil determining (palmitic, stearic, oleic, and linoleic) also indicate a similar FA composition of the studied samples. Conclusions. The studied samples of sunflower oil refined in terms of the content of basic FAs meet the requirements of the EP. The obtained results indicate the high stability of the oil and the absence of a significant effect of the storage period on the FA composition.

The Sur7/PalI family transmembrane protein Tos7 (Yol019w) plays a role in secretion in budding yeast

Tos7 (Yol019w) is a Sur7/PalI family transmembrane protein in the budding yeast Saccharomyces cerevisiae. Since the deletion of TOS7 did not affect growth or cell morphology, the cellular roles of Tos7 have not been established previously. Here, we show that high-copy TOS7 expression suppressed the growth defect of the secretion-defective RGA1-C term-overexpressing mutant and sec15-1 mutant. Moreover, Tos7 physically interacted with Boi2 and the Rho GTPase Rho3, two key regulators of exocyst assembly, suggesting that Tos7 plays a role in secretion. We also show that the deletion of TOS7 rendered the cells more sensitive to the cell wall-disrupting agents Congo red and calcofluor white while high-copy TOS7 expression had an opposite effect, suggesting that Tos7 affects cell wall organization. Finally, we show that Tos7 localized to punctate patches on the plasma membrane that were largely co-localized with the plasma membrane microdomains named MCC (membrane compartment of Can1). Together, these results suggest that Tos7 contributes to cell surface-related functions. Tos7 is likely an auxiliary component of MCC/eisosome that specifically interacts with the secretory pathway.

Design of Variable Auxiliary Noise Influence Ratio for Adaptive Active Vibration Control

Active vibration control (AVC) is an effective way to reduce low-frequency vibration. Accurate secondary path modeling (SPM) is crucial for the implementation of AVC system based on filtered-x least mean square (FXLMS) algorithm. The FXLMS algorithm with online SPM comprises two filters, i.e., an active control filter and an online SPM filter. Mutual interference between them is the key factor that restricts the performance of AVC system with online SPM. This paper designs a novel approach based on variable auxiliary noise influence (ANI) ratio to measure the contrastive relationship of convergence status between the active control filter and the online SPM filter. Based on the proposed variable ANI ratio, the proportion of auxiliary noise component in residual vibration is scheduled. Furthermore, a variable step-size strategy is derived to realize fast and stable online SPM. Comparative simulations with the competing methods are carried out in the case of secondary path sudden change and broadband vibration control. The simulation results indicate that the proposed method gives better performance than the other competing methods.

Infrared Wavefront Sensing for Adaptive Optics Assisted Galactic Center Observations with the VLT Interferometer and GRAVITY: Operation and Results

This article describes the operation of the near-infrared wavefront sensing based Adaptive Optics (AO) system CIAO. The Coudé Infrared Adaptive Optics (CIAO) system is a central auxiliary component of the Very Large Telescope (VLT) interferometer (VLTI). It enables in particular the observations of the Galactic Center (GC) using the GRAVITY instrument. GRAVITY is a highly specialized beam combiner, a device that coherently combines the light of the four 8-m telescopes and finally records interferometric measurements in the K-band on 6 baselines simultaneously. CIAO compensates for phase disturbances caused by atmospheric turbulence, which all four 8 m Unit Telescopes (UT) experience during observation. Each of the four CIAO units generates an almost diffraction-limited image quality at its UT, which ensures that maximum flux of the observed stellar object enters the fibers of the GRAVITY beam combiner. We present CIAO performance data obtained in the first 3 years of operation as a function of weather conditions. We describe how CIAO is configured and used for observations with GRAVITY. In addition, we focus on the outstanding features of the near-infrared sensitive Saphira detector, which is used for the first time on Paranal, and show how it works as a wavefront sensor detector.

Altered expressions and splicing profiles of Acin1 transcripts differentially modulate brown adipogenesis through an alternative splicing mechanism

Apoptotic chromatin condensation inducer in the nucleus (also referred as Acin1) was first characterized as an RNA-binding protein involved in apoptosis. In later reports, Acin1 was identified as an auxiliary component of the exon junction complex (EJC) which is assembled throughout pre-messenger RNA splicing. In this study, results of whole-transcriptome analyses revealed reduced expressions and reprogrammed splicing profiles of Acin1 transcripts throughout development of brown adipose tissues (BATs) that execute non-shivering thermogenesis in small rodents and infants by consuming lipids. Depletion of endogenous Acin1 isoforms led to activation of brown adipogenic signatures in mouse C3H10T1/2 fibroblasts. Nevertheless, overexpressions of the Acin1-L or Acin1-S isoform exerted discriminative influences on brown adipogenesis and reprogramming of the expression of serine/arginine-rich splicing factor 3 (SRSF3) through an alternative splicing-coupled nonsense-mediated decay mechanism in a sequence-specific manner. Moreover, the Acin1-SRSF3 axis constitutes a regulatory pathway that participates in the brown adipocyte-related splicing network. Taken together, the interplay between accessory EJC components and splicing regulators constitutes an emerging mechanism for differentially manipulating the activity of brown adipogenesis via alternative splicing network.

Reconfigurable holographic antenna with low sidelobe level based on liquid crystals

A novel liquid crystal (LC)-based holographic antenna (HA) with low sidelobe level is proposed in this paper to achieve large beam scanning range and multi-beam scanning property. The operating principle and the design procedure of the LC HA are presented. The influence of the on-to-off ratio of the holographic array element on the reconfigurable HA’s radiation characteristics is investigated. It is shown that the larger on-to-off ratio can reduce the sidelobe level of the reconfigurable HA, or decrease the iteration number of sidelobe optimization algorithms and enable the algorithms to converge to a much lower optimal sidelobe level. An effective design method to increase the array element’s on-to-off ratio is proposed through introducing an auxiliary radiation component, which offsets the radiation for the turn off state and enhances the radiation for the turn on state. A prototype of the LC HA consisting of the elements with large on-to-off ratio is designed and simulated to demonstrate the design method and theoretical predictions. Results show that, benefiting from the enhanced on-to-off ratio, the LC HA naturally presents a sidelobe level of −12.2 dB at broadside without any optimization. Compared with previous work, the sidelobe level is 3.2 dB lower than the case without large on-to-off ratio. Moreover, the proposed LC HA shows a quite large beam scanning range rising from −57.7° to +57.4° and a dynamic multi-beam property.

The Methods and Experiments of Shape Measurement for Off-Axis Conic Aspheric Surface.

The off-axis conic aspheric surface is widely used as a component in modern optical systems. It is critical for this kind of surface to obtain the real accuracy of the shape during optical processing. As is widely known, the null test is an effective method to measure the shape accuracy with high precision. Therefore, three shape measurement methods of null test including auto-collimation, single computer-generated hologram (CGH), and hybrid compensation are presented in detail in this research. Although the various methods have their own advantages and disadvantages, all methods need a special auxiliary component to accomplish the measurement. In the paper, an off-axis paraboloid (OAP) was chosen to be measured using the three methods along with auxiliary components of their own and it was shown that the experimental results involved in peak-to-valley (PV), root-mean-square (RMS), and shape distribution from three methods were consistent. As a result, the correctness and effectiveness of these three measurement methods were confirmed, which are very useful in engineering.

Research on the Performance of Accumulators Driven by an Electronically Controlled Hydraulic Vehicle

In order to study the performance of an accumulator during the start up of an electronically controlled hydraulic vehicle, theoretical analysis and establishment of a 1/4 vehicle experimental platform for experimental verification were conducted, in order to study the performance characteristics of the hydraulic circuit during driving. Control experiments show that the accumulator does not affect the acceleration performance and the torque of the hydraulic motor when an electrically controlled hydraulic vehicle is driven. The accumulator can be used as an auxiliary power component to absorb partially wasted energy during driving to improve the energy utilization efficiency. The energy absorbed by the accumulator during driving can increase the maximum speed; the use of the accumulator can alleviate the hydraulic shock at the entrance of the hydraulic motor.

Numerical Investigation on a Packed-Bed LHTES System Integrated into a Micro Electrical and Thermal Grid

Currently, energy storage systems are considered a key solution when mismatch occurs between energy supply and demand, allowing a more efficient energy deployment and use. The present paper is focused on the study of a latent heat thermal energy storage (LHTES) system based on a packed bed of encapsulated phase change material (PCM) of spherical shape, conceived as an auxiliary component of a micro-grid to be built in a Research Center located in southwestern Sardinia (Italy). The main purpose of this work was to perform numerical simulations for predicting the performance of the TES system, designed to store the surplus thermal energy produced during the weekend by a heat pump fed by a photovoltaic (PV) plant. The stored energy would then be utilized during the weekdays to integrate the air-conditioning system supply. The numerical simulations were based on a one-dimensional (1-D) two-equation transient model, able to return the thermocline profile of the water and the PCM separately. The behavior of the LHTES device during charge and discharge phases was reproduced, as well as during the standby periods. Finally, two characteristic indexes of the PV system were evaluated, to investigate the effect of TES on grid interchanges, self-consumption, and self-sufficiency.

Volkov\u2013Akulov\u2013Starobinsky supergravity revisited

We find new realizations of Volkov–Akulov–Starobinsky supergravity, i.e. Starobinsky inflationary models in supergravity coupled to a nilpotent superfield describing Volkov–Akulov goldstino. Our constructions are based on the no-scale Kähler potential K=-3log (T+overline{T}) for the inflaton field, and can describe de Sitter vacuum after inflation where supersymmetry is broken by the goldstino auxiliary component. In fact, we show that a more general class of models with K=-alpha log (T+overline{T}) for 3le alpha lesssim 6.37 can accomodate Starobinsky-like inflation with the universal prediction n_ssimeq 1-frac{2}{N_e} and rsimeq frac{4alpha }{(alpha -2)^2N_e^2}, while for 6.37lesssim alpha lesssim 7.23 viable hilltop inflation is possible (with n_s and r close to the above expressions). We derive the full component action and the masses of sinflaton, gravitino, and inflatino that are generally around the inflationary Hubble scale. Finally, we show that one of our models can be dualized into higher-derivative supergravity with constrained chiral curvature superfield.

A modified low voltage triggered silicon controlled rectifier (SCR) for ESD applications

In this paper, a modified low voltage triggered silicon-controlled rectifier (MLVTSCR) with low trigger voltage and high holding voltage has been proposed and implemented in both 28 nm CMOS process and 0.18 μm CMOS process. By segmenting the N+ active area bridged on the PW/NW junction of LVTSCR into blocks by P+ region, MLSCR was integrated into LVTSCR. The p+ blocks and the n+ blocks are alternately arranged and aligned in the same strip, in this way the proposed MLVTSCR is implemented. Without any extra mask as well as auxiliary trigger component, the proposed MLVTSCR possesses a very low trigger voltage and an adjustable high holding voltage from 2.05 to 4.29 V in 28 nm CMOS process and from 3.32 to 7.3 V in 0.18 μm BCD process under the TLP test, making it a superior candidate for electrostatic discharge protection in the 3.3 V/5 V CMOS processes. TCAD simulations has also been carried out to explore the intrinsic physical mechanisms of the proposed devices.

Design and Realization of a Compact High-Precision Capacitive Absolute Angular Position Sensor Based on Time Grating

This article proposes a compact and high precision capacitive absolute angular position sensor based on time grating. The sensor consists of a stator and a rotor with three concentric capacitor structures forming primary and auxiliary angular displacement measurement components. The primary component combines a single middle-row capacitive structure with an outer-row capacitive structure to obtain high-precision displacement measurements composed of N measurement periods. The auxiliary component employs a single inner-row capacitive structure with a single spatial period over the 360° measurement range of the sensor in conjunction with a remodulation scheme to obtain displacement measurements composed of N - 1 measurement periods. Combining the measurements of the primary and auxiliary components in a manner similar to vernier calipers yields high-precision absolute angular position measurements. The sensor design and remodulation scheme facilitate good sensor compactness. The measurement performance of the proposed design is evaluated via tests of a prototype sensor with an outer diameter of 60 mm fabricated by printed circuit board technology. The prototype sensor is demonstrated to obtain a measurement resolution of 3" and a measurement accuracy of ±10" over the 360° measurement range of the sensor, indicating that the proposed sensor design has considerable potential for high precision applications.

Analisis Penggunaan Politeness Strategi Irai Hyougen (Shuuketsubu) Berdasarkan Jouge Kankei oleh Mahasiswa Bahasa Jepang di Daerah Istimewa Yogyakarta

Request Expression or Irai hyougen is an expression widely used in daily life. In its use, Irai hyougen consists of three parts, namely Senkoubu (Prolog), Iraibu (Statement of Request), after the request has a disclose, it will usually continue to make a promise and the expression process ends. Still, the researchers used a reminder to confirm the previous request or the so-called Shuuketsubu. Irai Hyougen Shuuketsubu usually consists of reminiscent expressions and confirmation expressions (Xu, 2007). Irai hyougen is an expression that requires an appropriate communication strategy, so it is essential to know the politeness strategies used in Irai Hyougen Shuuketsubu , especially the reminding expression. The politeness strategy used will not be separated from the jouge kankei relationship. This study aims to find out what expressions used by seniors to juniors, between peers, and juniors to seniors in the college environment and also politeness used. The research data came from Japanese language learners in Yogyakarta Special Region. The method used was quantitative, using semantic formulas to analyze the expression strategies used. The results of this study indicate that senior speakers mostly use the main component in the form of a ban (Kinshi Hyougen), the auxiliary component, and discourse regulator. Colleague speakers used the main component in the form of a prohibition expression (Kinshi Hyougen) and the auxiliary component. In contrast, the junior used the main component and helper component. The politeness used by the three situations was a bald-on record strategy (without strategy) because the speaker and speech partner already know each other well.