Ordinary Temperatures Research Articles

Experimental investigation into temperature- and frequency-dependent dynamic properties of high-speed rail pads

In order to investigate the temperature- and frequency-dependent dynamic properties of high-speed rail pads excited by rail vehicle’s large-amplitude quasi-static loads due to bogie interval and wheelset spacing, the soft pads from WJ-7, WJ-8 and Vossloh 300 fasteners frequently used in China’s high-speed railway track systems are taken as test subjects. At first, a series of dynamic tests of the three high-speed rail pads at a specific frequency of 0.3Hz and under various low temperatures ranging from −60 to 20°C are carried out. Then, the Time-Temperature Superposition (TTS) and Williams-Landel-Ferry (WLF) formula are used to predict their dynamic performance at frequencies higher than the test frequency, and the Fractional Derivative Kelvin-Voigt (FDKV) model is proposed to represent their frequency-dependent dynamic properties. Finally, the frequency-dependent dynamic performance of the three high-speed rail pads under rail vehicle’s small-amplitude dynamic loads due to the surface roughness of rail and wheel is discussed. It is found that the storage stiffness of WJ-7, WJ-8 and Vossloh 300 rail pads is sensitive to low temperatures, as well as much larger than their corresponding loss stiffness. The glass transformation temperatures of WJ-7, WJ-8 and Vossloh 300 rail pads are −40, −45 and −45°C, respectively. The FDKV model can basically give a satisfactory fitting with the experimental results within 100Hz, especially at ordinary temperatures. The dynamic properties of rail pads excited by rail vehicle’s small-amplitude dynamic loads are time-variable and related to rail vehicle’s large-amplitude quasi-static load values on rail pads. Thus, it is very important that the temperature- and frequency-dependent dynamic parameters of the polymer materials in vehicle-track systems must be measured according to the specific operation conditions, since otherwise an accurate prediction of the broadband train-induced vibration and noise at different temperatures is difficult to achieve.

Isolating lattice from electronic contributions in thermal transport measurements of metals and alloys above ambient temperature and an adiabatic model

From femtosecond spectroscopy (fs-spectroscopy) of metals, electrons and phonons reequilibrate nearly independently, which contrasts with models of heat transfer at ordinary temperatures ([Formula: see text] K). These electronic transfer models only agree with thermal conductivity [Formula: see text] data at a single temperature, but do not agree with thermal diffusivity [Formula: see text] data. To address the discrepancies, which are important to problems in solid state physics, we separately measured electronic (ele) and phononic (lat) components of [Formula: see text] in many metals and alloys over [Formula: see text]290–1100 K by varying measurement duration and sample length in laser-flash experiments. These mechanisms produce distinct diffusive responses in temperature versus time acquisitions because carrier speeds [Formula: see text] and heat capacities [Formula: see text] differ greatly. Electronic transport of heat only operates for a brief time after heat is applied because [Formula: see text] is high. High [Formula: see text] is associated with moderate [Formula: see text], long lengths, low electrical resistivity, and loss of ferromagnetism. Relationships of [Formula: see text] and [Formula: see text] with physical properties support our assignments. Although [Formula: see text] reaches [Formula: see text] near 470 K, it is transient. Combining previous data on [Formula: see text] with each [Formula: see text] provides mean free paths and lifetimes that are consistent with [Formula: see text] K fs-spectroscopy, and new values at high [Formula: see text]. Our findings are consistent with nearly-free electrons absorbing and transmitting a small fraction of the incoming heat, whereas phonons absorb and transmit the majority. We model time-dependent, parallel heat transfer under adiabatic conditions which is one-dimensional in solids, as required by thermodynamic law. For noninteracting mechanisms, [Formula: see text]. For metals, this reduces to [Formula: see text] above [Formula: see text]20 K, consistent with our measurements, and shows that Meissner’s equation [Formula: see text] is invalid above [Formula: see text]20 K. For one mechanism with multiple, interacting carriers, [Formula: see text]. Thus, certain dynamic behaviors of electrons and phonons in metals have been misunderstood. Implications for theoretical models and technological advancements are briefly discussed.

Sustainable process for functional group introduction onto HOPG by exposing [rad]OH and 1O2 using a radical vapor reactor (RVR) without any chemical reagents

Efficient generation of reactive oxygen species (high concentrations of 1O2 and OH) was successfully performed using a radical vapor reactor (RVR) at ordinary temperature and atmospheric pressure without using any chemical reagent. In this study, we successfully introduced modified functional groups onto highly oriented pyrolytic graphite (HOPG) by a sustainable process using an RVR. Although the introduction of a functional group onto HOPG is difficult because of the presence of strong CC bonds in HOPG, the RVR can easily modify it because reactive oxygen species have high energy and high reactivity. Moreover, the RVR process does not require any chemical reagent; it also does not produce any exhaust, except for air and water. The RVR-treated HOPG was analyzed by contact angle measurement (CAM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM), and scanning tunneling microscopy (STM). These analyses revealed that the HOPG surface became hydrophilic and it showed different physical property owing to the modification caused by the introduced oxygen element.

Protocol and statistical analysis plan for the Randomised Evaluation of Active Control of Temperature versus Ordinary Temperature Management (REACTOR) trial

Background: Body temperature can be reduced in febrile patients in the intensive care unit using medicines and physical cooling devices, but it is not known whether systematically preventing and treating fever reduces body temperature compared with standard care.Objective: To describe the study protocol and statistical analysis plan for the Randomised Evaluation of Active Control of Temperature versus Ordinary Temperature Management (REACTOR) trial.Design, setting and participants: Protocol for a phase II, multicentre trial to be conducted in Australian and New Zealand ICUs admitting adult patients. We will recruit 184 adults without acute brain injury who are expected to be ventilated in the ICU beyond the day after randomisation. We will use open, random, parallel assignment to systematic prevention and treatment of fever, or to standard temperature management.Main outcome measures: The primary end point will be mean body temperature, calculated from body temperatures measured 6-hourly for 7 days (168 hours) or until ICU discharge, whichever is sooner. Secondary end points are ICU-free days, in-hospital and cause-specific mortality (censored at Day 90) and survival time to Day 90 (censored at hospital discharge).Results and conclusions: The trial will determine whether active temperature control reduces body temperature compared with standard care. It is primarily being conducted to establish whether a phase III trial with a patient-centred end point of Day 90 mortality is justified and feasible.

Thermal effects in dislocation theory. II. Shear banding.

The thermodynamic dislocation theory presented in previous papers is used here to describe shear-banding instabilities. Central ingredients of the theory are a thermodynamically defined effective configurational temperature and a formula for the plastic strain rate determined by thermally activated depinning of entangled dislocations. This plastic strain rate is extremely sensitive to variations of the stress and the ordinary temperature. As a result of this sensitivity, the system undergoes rapid shear banding instabilities when ordinary thermal relaxation is slow. It also undergoes rapid changes from elastic to plastic behaviors at yielding transitions.

Improving of Temperature Susceptibility of Asphalt 60/70 using Synthesized Reactive Rubber Nanoparticles for use in Different Climate

The use of reactive polymers as modifiers for asphalt appears promising. Asphalt penetration grade 60/70 cannot be used in coating applications for its long drying time at ordinary temperature and for its brittleness at very cold temperature. This material is very cheap as compared to blown asphalt that usually used in industrial applications. This study aims to use reactive polymers in modification of soft asphalt to produce very specific asphaltic material for use in infrastructure applications especially coating instead of highly expensive materials. The new asphaltic material is low cost and has high quality performance at low temperature. To achieve the aim of study, RRNP was used as additive to modify asphalt in percentages of 3, 5, 7 and 10% w/w. The prepared RRNP was then tested for their particles size using DLS and TEM, SEM, 1HNMR. RRNP was used to modify the thermo mechanical properties of asphalt via forming chemical bond, and the changing in mechanical and thermal properties of the mixes as well as the storage stability were studied. Also, the morphology (SEM), thermal characterization (TGA), Dynamic mechanical analysis (DMA), rheological tests, while, the prepared coatings were applied to carbon steel panel and tested for bending, Abarsion test and impact test were detected. Overall, the results show that the chosen modifiers are the best so far in the modification of soft asphalt to suit the industrial applications in different climate conditions.

Effect of temperature- and frequency-dependent dynamic properties of rail pads on high-speed vehicle–track coupled vibrations

ABSTRACTThe soft under baseplate pad of WJ-8 rail fastener frequently used in China’s high-speed railways was taken as the study subject, and a laboratory test was performed to measure its temperature and frequency-dependent dynamic performance at 0.3 Hz and at −60°C to 20°C with intervals of 2.5°C. Its higher frequency-dependent results at different temperatures were then further predicted based on the time–temperature superposition (TTS) and Williams–Landel–Ferry (WLF) formula. The fractional derivative Kelvin–Voigt (FDKV) model was used to represent the temperature- and frequency-dependent dynamic properties of the tested rail pad. By means of the FDKV model for rail pads and vehicle–track coupled dynamic theory, high-speed vehicle–track coupled vibrations due to temperature- and frequency-dependent dynamic properties of rail pads was investigated. Finally, further combining with the measured frequency-dependent dynamic performance of vehicle’s rubber primary suspension, the high-speed vehicle–track coupled vibration responses were discussed. It is found that the storage stiffness and loss factor of the tested rail pad are sensitive to low temperatures or high frequencies. The proposed FDKV model for the frequency-dependent storage stiffness and loss factors of the tested rail pad can basically meet the fitting precision, especially at ordinary temperatures. The numerical simulation results indicate that the vertical vibration levels of high-speed vehicle–track coupled systems calculated with the FDKV model for rail pads in time domain are higher than those calculated with the ordinary Kelvin–Voigt (KV) model for rail pads. Additionally, the temperature- and frequency-dependent dynamic properties of the tested rail pads would alter the vertical vibration acceleration levels (VALs) of the car body and bogie in 1/3 octave frequencies above 31.5 Hz, especially enlarge the vertical VALs of the wheel set and rail in 1/3 octave frequencies of 31.5–100 Hz and above 315 Hz, which are the dominant frequencies of ground vibration acceleration and rolling noise (or bridge noise) caused by high-speed railways respectively. Since the fractional derivative value of the adopted rubber primary suspension, unlike the tested rail pad, is very close to 1, its frequency-dependent dynamic performance has little effect on high-speed vehicle–track coupled vibration responses.

Thermal effects in dislocation theory.

The mechanical behaviors of polycrystalline solids are determined by the interplay between phenomena governed by two different thermodynamic temperatures: the configurational effective temperature that controls the density of dislocations, and the ordinary kinetic-vibrational temperature that controls activated depinning mechanisms and thus deformation rates. This paper contains a review of the effective-temperature theory and its relation to conventional dislocation theories. It includes a simple illustration of how these two thermal effects can combine to produce a predictive theory of spatial heterogeneities such as shear-banding instabilities. Its main message is a plea that conventional dislocation theories be reformulated in a thermodynamically consistent way so that the vast array of observed behaviors can be understood systematically.

Stabilization of carbon dioxide and chromium slag via carbonation

ABSTRACT As the main greenhouse gas, CO2 is considered as a threat in the context of global warming. Many available technologies to reduce CO2 emission was about CO2 separation from coal combustion and geological sequestration. However, how to deal with the cost-effective storage of CO2 has become a new challenge. Moreover, chromium pollution, the treatment of which requires huge energy consumption, has attracted people’s widespread attention. This study is aimed to develop the sequestration of CO2 via chromium slag. A dynamic leaching experiment of chromium slag was designed to testify the ability of CO2 adsorption onto chromium slag and to release Cr(VI) for stabilization. The results showed that the accumulative amounts of Cr(VI) were ca. 2.6 mg/g released from the chromium slag after 24 h of leaching. In addition, ca. 89 mg/g CO2 was adsorbed by using pure CO2 in the experiment at 12 h. Calcite is the only carbonate species in the post-carbonated slag analyzed by powder X-ray diffraction and thermal analysis. The approach provides the feasibility of the utilization of chromium slag and sequestration of the carbon dioxide at the same time at ordinary temperatures and pressures.

Enantioselective Cyclopropanation of a Wide Variety of Olefins Catalyzed by Ru(II)-Pheox Complexes.

The transition-metal-catalyzed asymmetric cyclopropanation of olefins with diazoacetates has become one of the most important methods for the synthesis of optically active cyclopropane derivatives, which are key pharmaceutical building blocks and present in a large number of natural products. To date, significant progress has been made in this area of research, and efficient stereocontrolled synthetic approaches to cyclopropane derivatives have been developed using rhodium, ruthenium, copper, and cobalt catalysts. However, the vast majority of these strategies are limited to electron-rich olefins, such as styrene derivatives, due to the electrophilicity of the metal-carbene intermediates generated from the reaction of the metal with the diazo compound. Recently, the D2-symmetric Co(II)-phophyrin complexes developed by Zhang et al. were shown to be the most efficient catalysts for the asymmetric cyclopropanation of electron-deficient olefins. This catalytic system is mechanistically distinct from the previous rhodium and copper catalytic systems, proceeding via radical intermediates. However, the asymmetric cyclopropanation of vinyl carbamates, allenes, and α,β-unsaturated carbonyl compounds has rarely been reported. Therefore, the development of new powerful catalysts for the asymmetric cyclopropanation of a wide range of olefinic substrates is the next challenge in this field. In this Account, we summarize our recent studies on the Ru(II)-Pheox-catalyzed asymmetric cyclopropanation of various olefins, including vinyl carbamates, allenes, and α,β-unsaturated carbonyl compounds. We demonstrate that the developed catalytic system effectively promotes the asymmetric cyclopropanation of a wide variety of olefins to produce the desired cyclopropane products in high yields with excellent stereocontrol. The use of succinimidyl-, ketone-, and ester-functionalized diazoacetates as carbene sources was found to be crucial for the high stereoselectivity of the cyclopropanation reactions. In addition, we describe reusable chiral Ru(II)-Pheox catalysts, namely, water-soluble Ru(II)-hm-Pheox and polymer-supported PS-Ru(II)-Pheox, which can be reused at least five times in inter- and intramolecular cyclopropanation reactions without any significant loss of catalytic activity or enantioselectivity. These Ru(II)-Pheox-catalyzed asymmetric cyclopropanation reactions provide an elegant method to access a series of optically active cyclopropane derivatives, including cyclopropylamines, dicarbonyl cyclopropanes, alkylidenecyclopropanes, and cyclopropane-fused γ-lactones, which are intermediates in the syntheses of various biologically active compounds. The novel chiral Ru(II)-Pheox complexes are readily synthesized in high yield from inexpensive, commercially available benzoyl chloride and amino alcohols, then fully characterized using X-ray diffraction analysis, NMR, and elemental analysis. These catalysts are easy to handle and stable under ordinary temperatures and conditions and can be used after three months of storage without any loss of catalytic activity or stereoselectivity.

Nonlinear two-dimensional terahertz photon echo and rotational spectroscopy in the gas phase.

Ultrafast 2D spectroscopy uses correlated multiple light-matter interactions for retrieving dynamic features that may otherwise be hidden under the linear spectrum; its extension to the terahertz regime of the electromagnetic spectrum, where a rich variety of material degrees of freedom reside, remains an experimental challenge. We report a demonstration of ultrafast 2D terahertz spectroscopy of gas-phase molecular rotors at room temperature. Using time-delayed terahertz pulse pairs, we observe photon echoes and other nonlinear signals resulting from molecular dipole orientation induced by multiple terahertz field-dipole interactions. The nonlinear time domain orientation signals are mapped into the frequency domain in 2D rotational spectra that reveal J-state-resolved nonlinear rotational dynamics. The approach enables direct observation of correlated rotational transitions and may reveal rotational coupling and relaxation pathways in the ground electronic and vibrational state.

H2O-driven generation of picritic melts in the Middle to Late Triassic Stuhini arc of the Stikine terrane, British Columbia, Canada

Basaltic to andesitic compositions predominate island arc magmatism; ultramafic magmas are rare. Ultramafic (MgO = 21–33 wt.%) tuff breccia, lapilli tuff, and ash tuff of the Middle to Upper Triassic Stuhini Group were erupted in the Stikine arc of the North American Cordillera shortly preceding an episode of prolific porphyry Cu–Mo(–Au) mineralization. The ultramafic tuff shows accumulation (20–65%) of olivine (Fo91) and minor chromite into a subalkaline picritic parental magma with MgO ∼16 wt.%. Despite the inferred high MgO content of the parental liquid, chromite phenocrysts record relatively low liquidus temperatures (<1200 °C) suggesting crystallization from relatively low temperature, hydrous melts, at oxygen fugacities one to three log units above the fayalite–magnetite–quartz (FMQ) buffer. The primary picritic magmas likely contained 5–7 wt.% H2O, inferred on the basis of olivine-liquid thermometry and thermal models for subduction zones, thus alleviating the need for catastrophic thermal perturbations in the mantle wedge. Instead, efficient release of water through slab dehydration at 2.5–3.0 GPa allows generation of picritic melts at ordinary mantle wedge temperatures through moderate degrees (F=0.10–0.15) of hydrous flux melting. The volatile-rich nature of the melt and the predominant extensional regime in the overlying lithosphere of Stikinia facilitated the near-adiabatic ascent of the Stuhini Group picrites. The high H2O content of the rapidly ascending picrite melt may have played a key role in transport of metals into the crust of the Stikinia and subsequent porphyry mineralization.

Semi-Open Thermal Protection Scheme of Electronics in Nuclear Rescue Robot

Thermal management of electronics is quite important for safe operation of nuclear rescue robot. However, the ambient temperature of the nuclear robot in the site of nuclear accident will suffer an alternation between ordinary and elevated temperature. Traditional phase change material (PCM) based closed scheme for thermal protection is not suitable due to the capacity limitation of PCM. Open scheme with forced air cooling or water cooling is not acceptable either, because it cannot operate in high temperature. Therefore, a semi-open thermal control scheme is proposed by using silica aerogel for heat insulation, PCM for heat absorption, and Nickel-titanium alloy spring as temperature switch. An investigation on different ambient temperature, laying angle, melting point of PCM and heat power is conducted. The results showed that, compared with the PCM-based closed scheme, our design can provide 19.23% prolonged safe working hours, which can improve the reliability of electronic devices.

상온 조건에서 혐기 소화 상징액을 이용한 아질산화 반응과 운전 인자의 상관성 분석

상온 조건에서 혐기 소화 상징액을 이용한 아질산화 반응과 운전 인자의 상관성 분석

Research of Influence Modification of Natural Concentrate on Quality Metal

Questions of increase of mechanical, technological and service properties of metal at minimum cost to produce it are relevant for the metallurgical enterprises.Modification of complex steel alloys containing reactive elements is one of the effective ways to improve the quality of steel. At the same time the direct costs for the use of modifiers are 0.2-0.3%, which little effect on the cost of production.The paper presents the results of the application of natural concentrates as a modifier steel. The effects on the metal quality changes due to the impact of the modification concentrates demonstrate the effectiveness of their application. As a result of modification decreased the content of nonmetallic inclusions and grain size. Reduction of impurity modified metal of was the cause more high plastic properties, especially, impact strength at ordinary and low temperatures of tests. Based on the experimental data evaluated hardening mechanisms that lead to a significant improvement of physic-mechanical properties of the metal workpiece after administration modifier.

Adaptive glass panels using shape-memory alloys

Due to the growing application of laminated glass panels in building facades and roofs, tending towards the minimization of frameworks, substructures and supports, technological solutions based on the use of glass panels with increasingly wide dimensions and modern design principles are becoming more frequent. The growing use of structural glass applications is leading to “lighter” and “smarter” optimized design solutions. The design of such applications greatly depends on the material mechanical properties of their structural elements and on their sensitivity to ambient and loading conditions. This is the specific case of laminated glass, where a temperature and time loading sensitive interlayer is generally used to bond together two (or more) glass panes with brittle behavior and rather limited tensile resistance. In this research paper, a novel adaptive glass panel concept is developed by using shape-memory alloy (SMA) cables, and assessed by means of Finite-element numerical studies and experimental validation. Based on the case study of an existing laminated glass roof panel, several geometrical configurations of practical interest are investigated. A key role in the proposed approach is the application of external pre-stressing based on the Joule heating of the SMA bracing system. The structural efficiency of the cable system is emphasized by taking into account the effects of ordinary wind pressures and temperature variations. Due to the innovative adaptive control system, as shown, the structural performance of traditional laminated glass panels can be enhanced, e.g. optimized in terms of maximum displacements and stresses in the glass, as well as in the overall dimensions and thicknesses of the glass panes.

High pressure CO2 solubility and physical properties of tetrabutylphosphonium l-prolinate

This paper reports the CO2 solubility, density, viscosity, and electrical conductivity for a kind of amino acid ionic liquid (AAIL), tetrabutylphosphonium l-prolinate ([P4444][Pro]). The physical properties of [P4444][Pro] showed the ordinary temperature dependency, i.e. the density and viscosity decreased and the electrical conductivity increased with a temperature rising. One mole of [P4444][Pro] absorbed a 0.970 mol of CO2 at atmospheric pressure of CO2 and 333.2 K, and desorbed only ∼17% of the absorbed CO2 at 393.2 K. NMR spectra revealed that a CO2 molecule formed a complex with [Pro]−, and [P4444]+ had a little effect on the CO2 absorption. The CO2 solubility increased steeply at lower pressures of CO2 < 0.1 MPa and very gradually in the higher pressure range from 0.1 to 6 MPa at 333.15 K. Other tetrabutylphosphonium AAILs with (S)-2-methylprolinate ([P4444][MePro]) and glycinate ([P4444][Gly]) showed the similar pressure dependencies. The contributions of physical and chemical absorptions to the total CO2 solubility were analyzed to discuss the effect of anion on the high-pressure CO2 solubility. [P4444][Pro] and [P4444][Gly] showed the higher physical and chemical CO2 absorptions (in molarity scale) in the present AAILs, respectively.

Development of a gas/liquid phase change actuator for high temperatures

Gas/liquid phase changes produce large volume changes in working fluids. These volume changes are used as the driving power sources in actuators such as micro-pumps and valves. Most of these actuators are utilized in ordinary temperature environments. However, the temperature range in which the phase change actuator can operate depends on the characteristics of the working fluid. We hypothesized that proper selection of the working fluid and the structure of the actuator can enable such actuators to be applied not only in ordinary environments but also in high temperature environments. Consequently, in this paper, we discuss the design and fabrication of a new gas/liquid phase change actuator for use in high temperature environments. Our proposed actuator consists of a bellow body, spring, heater, and working fluid. We used the Inconel super alloy, which is highly heat and corrosion resistant, for the bellow and moving parts of the actuator. For the working fluid, we prepared triethylene glycol, which has a boiling point of 287.3 °C and very low vapor pressure at ordinary temperature. As a result, our proposed actuator can be utilized in high temperature environments up to 300.0 °C. The results of several experiments conducted confirm that our proposed actuator generates 1.67 mm maximum displacement in a 300.0 °C atmospheric environment. In addition, we confirmed that the operation of the actuator is stable in that environment. Our results confirm that a gas/liquid phase change actuator can be used in high temperature environments.

Copper Aluminum Nano Junction Normal Temperature Processes and Methods Applied to the LED High Heat Transfer Performance

High-power light-emitting diodes (LED) have extremely broad applications. However, with the job requirements of high-brightness and high color temperature from light-emitting diodes, it must be followed to enlarge the operating current, thus heating up more rapidly. If its heat dissipation problem cannot be effectively solved, operation will be prone to bring about color shift, and it may even considerably shorten its life. Moreover, application value will therefore be greatly reduced. So in order to enhance the high-power LED luminous brightness and life to cope with the future development needs of high-power LED components, it is necessary to replace the use of conductive silver paste to stick thermally conductive Cu slug fixing grain and lead frame heat dissipation aluminum sheet. This is done by directly bonding thermally conductive Cu slug with pure aluminum, the formation of highly efficient direct heat conduction cooling structure. Therefore the topic points at the crux of the LED heat dissipation difficulty, puts forward of copper and aluminum bonding technology in the ordinary temperature and pressure, method to effectively improve thermal conductivity performance between LED die bond Cu slug and joining aluminum cooling module. This will ultimately make the LED's operation and applications perfect.

放射光X線分光を駆使したステンレス鋼表面における自然不動態被膜の構造解析

A native passive film is formed on the SUS304 surface at ordinary temperature and pressure1, 2). As a structural model of the film, a network-structure composed of Cr-oxide and -hydroxide has ever been proposed1, 3), but experimental evidences for the structure have not been reported yet. We examined the detailed film structure using synchrotron X-ray absorption fine structure (XAFS) and X-ray photoelectron spectroscopy (XPS). The XAFS spectra clearly showed an ordered network-structure (at least < 10 Å) of Cr(IV) oxide. Additionally, the XPS spectra indicated that the chromium oxide is transformed into a chromium oxyhydroxide such as a -O-Cr-OH- structure. These results are the first evidence that the network structure exists actually in the native passive film of SUS304.