Search

We develop a theory of sheaves and cohomology on the category of proper modulus pairs. This complements [KMSY21], where a theory of sheaves and cohomology on the category of non-proper modulus pairs has been developed.

We develop a theory of modulus sheaves with transfers, which generalizes Voevodsky's theory of sheaves with transfers. This paper and its sequel are foundational for the theory of motives with modulus, which is developed in [KMSY20].

Novel organic-inorganic hybrid materials were developed as LED sealants. Polysilsesquioxane with an -SH group (PSQ-SH) and acrylic monomer were selected as the inorganic and organic components, respectively. Trimethylolpropane trimethacrylate (TRIM), which is a trifunctional monomer, was selected as an acrylic monomer, and curing of the material was performed by the thiol-ene reaction. The LED was sealed using the prepared PSQ-SH/TRIM hybrid material (PTH), and a light emission test was performed. However, cracks occurred in the hybrid material during lighting. Therefore, ditrimethylol propane tetraacrylate (DTMPTA), which is a tetrafunctional monomer, was selected for the first time to prepare a PSQ-SH/DTMPA hybrid material (PDH) in order to enhance the strength and heat resistance of the material. The characteristics of the novel PDH were evaluated and compared with those of PTH. Specifically, the heat resistance was evaluated by confirming the onset temperature of weight reduction using thermogravimetry-differential thermal analyzer (TG-DTA) analysis, and the mechanical strength was also evaluated by bonding the glass substrates with a hybrid material and measuring the sealing strength. In conclusion, it was possible to suppress crack generation during lighting by using PDH instead of PTH in the light emission test.

This work aims to increase the interface between anode and electrolyte in solid oxide fuel cells by controlling the 3D microstructure with a commercial ink-jet 3D printer. Anode and electrolyte inks suitable for use in a 3D printer were prepared by altering the viscosity and the droplet size. A porous anode structure that ensures a flow path for gases was achieved by addition of acrylic particles into the anode ink. A dense electrolyte structure that prevents leakage was created. The anode and electrolyte layers were produced as long, flat strips which were aligned in parallel to form sheets; these sheets were stacked orthogonally to complete the 3D microstructure called the ‘anode functional layer’. The anode functional layer was roughly 100 micrometers on a side with a thickness of 4 micrometers. The anode functional layer was inserted between the anode and electrolyte. The assembled solid oxide fuel cell showed high performance when tested at 600 °C with dry methane as the fuel source.

Reduction of the energy penalty and cost of CO2 capture from concentrated gas streams using amine-based solutions can be achieved by minimizing the energy penalty in the solvent regeneration process. High concentration 2-Amino-2-methyl-1-propanol (AMP) solution precipitates as a carbonate when enough CO2 has been absorbed. By sending the separated carbonate to the stripper, the sensible heat of regeneration can be reduced. However, previous testing using 50 weight percent AMP solution mixed with Piperazine (PZ) with solid-liquid separation showed that the CO2 recovery rate was limited to 65% due to the lack of PZ regeneration. To improve the CO2 recovery rate, a novel solution and injection process were developed. N-Methyl-1,3-diaminopropane (MAPA) was selected as an alternative promoter based on reaction rate testing. Various tests were employed to characterize the behaviour of the AMP/MAPA solution under CO2 capture and recovery conditions. The injection point was relocated to avoid the inhibition of CO2 absorption observed when CO2 semi-lean liquid was sent to the upper portion of the absorber. The CO2 recovery rate and the precipitation quantity were simulated using a model built in Aspen Plus®. The novel solution and injection set-up were evaluated experimentally by a bench-scale apparatus.

Historicamente, o estabelecimento de áreas naturais protegidas, como as Unidades de Conservação, tem dado margem a complexas situações de conflitos socioambientais, seja pela realocação das populações residentes em tais áreas, seja pela restrição ao acesso e uso costumeiro dos recursos naturais contidos nela. Diante desse cenário, o presente artigo de revisão de literatura focaliza os conflitos socioambientais, especialmente aqueles que se dão em torno de Unidades de Conservação de Proteção Integral, elucidando as principais correntes do ambientalismo que discursam sobre o tema. A partir do aprofundamento teórico sobre a temática, observa-se que o campo é permeado por discussões entre socioambientalistas e conservacionistas, que travam juntos uma intensa discussão sobretudo acerca do direito dessas populações de permanecerem e utilizarem os recursos dessas áreas versus a necessidade de conservar um ecossistema sem a presença humana.

Eponyms are used almost daily in the clinical practice of dermatology. And yet, information about the person behind the eponyms is difficult to find. Indeed, who is? What is this person's nationality? Is this person alive or dead? How can one find the paper in which this person first described the disease? Eponyms are used to describe not only disease, but also clinical signs, surgical procedures, staining techniques, pharmacological formulations, and even pieces of equipment. In this article we present the symptoms starting with (F). The symptoms and their synonyms, and those who have described this symptom or phenomenon.

Multi-wire saws with a diamond electrodeposited wire tool are widely used to slice hard and brittle materials. The properties of the materials significantly affect the saw’s performance in terms of slicing quality, efficiency, and accuracy. In this study, the effects of the material properties of workpieces on wire tool performance and tool wear are described. The main conclusions are as follows: the higher the hardness and toughness of the workpiece material, the longer the slicing time and greater the damage to the wire tool. The brittleness of the workpiece adversely affects the thickness variation more than its hardness. In addition, the frequency of chipping mainly depends on the hardness of the workpiece, whereas the chipping size mainly depends on the toughness of the workpiece.

The manufacturing costs of semiconductor products such as silicon wafers can be reduced by decreasing the kerf loss. In addition, a decrease in the kerf loss leads to an effective utilization of rare materials, which is environmentally beneficial from the viewpoint of saving resources. This study aims to reduce the kerf loss during slicing hard and brittle materials. Therefore, the possibility of using an extremely thin metal foil blade instead of a wire tool in slicing was examined. Initially, grooving characteristics using a metal foil blade (thickness: 50 μm or less) was investigated. The main conclusions are that grooving with a metal foil blade is possible and kerf loss can be reduced. The groove depth tends to increase as the machining time and particle size of abrasives increase. The groove width is smaller when a thin metal foil blade is used and vice versa. However, if the abrasive particle size is too large, grooving becomes impossible. Since the wear of metal foil blade increases with an increase in the particle size of the abrasive, it is necessary to use an abrasive with a particle size that is suitable for the thickness of the metal foil blade.

A two-step process consisting of pyrolysis of dried sludge and catalytic upgrading of pyrolysed liquid was proposed. Wastewater from a palm oil mill was separated to solid cake and liquid by filtration. The solid cake was dried and pyrolysed at 773 K. Liquid product obtained from the pyrolysis had two immiscible aqueous and oil phases (PL-A and PL-O). Identification of chemicals in PL-A and PL-O indicated that both phases contained various chemicals with unsaturated bonds, such as carboxylic acids and alcohols, however, most of the chemicals could not be identified. Catalytic upgrading of PL-A and PL-O over ZrO2·FeOx were separately performed using a fixed bed reactor at various conditions, T = 513-723 K and mass of catalyst to feed rate = 0.25-10 h. The main components in the liquid products of PL-A upgrading were methanol and acetone whereas they were acetone and phenol in the case of PL-O upgrading. More than 15% of carbon in raw material was deposited on the catalyst. To reduce the carbon deposition, the used catalyst was treated with air at 823 K. This simple treatment could reasonably regenerate the catalyst only for the case of PL-A catalytic upgrading.

Résumé: Cet article questionne le rapport entre le fantastique et l’idéologique qui se côtoient dans la structure narrative du conte africain. L’étude s’appuie sur deux récits édités à près d’un demi-siècle d’intervalle. Malgré le temps qui les sépare, il y a une constante qui caractérise les deux contes. Leur trame narrative baigne dans un fantastique manifeste porté par des personnages irréels et un déroulement improbable d’actions. Mais en dessous de cet univers fantasmagorique s’expriment non seulement des enseignements didactiques mais aussi des conceptions du monde des sociétés dont les auteurs ne sont que les porte-paroles. Le réel et l’irréel se superposent donc dans le conte, lui donnant ainsi un statut fascinant et permanent qui l’inscrit intemporellement dans les formes de paroles codifiées entretenues par les différentes sociétés. Mots-clés : conte, fantastique, conceptions du monde, enseignements didactiques

The generalized Frobenius number is the largest integer represented in at most $p$ ways by a linear combination of nonnegative integers of given positive integers $a_1,a_2,\,\dots ,\,a_k$. When $p=0$, it reduces to the classical Frobenius number. In this paper, we give the generalized Frobenius number when $a_j=(b^{n+j-1}-1)/ (b-1)$ ($b\ge 2$) as a generalization of the result of $p=0$ in [16].

Picosecond dynamics of the photoexcited charge-ordered perovskite-type cobalt oxides La$_{{1.5}}$Ca$_{{0.5}}$CoO$_{{4}}$ and La$_{{1.5}}$Sr$_{{0.5}}$CoO$_{{4}}$ were investigated based on time-resolved Raman and reflection spectroscopy. These cobalt oxides show strong Raman scattering at around $700~\mathrm{cm}^{-1}$, originating from the breathing vibration mode of the CoO$_{{6}}$ octahedron coupled with the checkerboard-type charge ordering of Co$^{{2+}}$ and Co$^{{3+}}$. We performed time-resolved Raman and reflection spectroscopy by photoirradiating with picosecond pulses at 400 nm, exciting the charge transfer (CT) transition from the O $2p$ site to the Co $3d$ site. As a result of the excitation, the Raman intensity of the breathing mode was suppressed by $10\%$ on a similar time scale in the reflectance change without changing the frequency of the mode, directly indicating ultrafast suppression of the order parameter of the charge-ordered state by CT transition.

In Japan, many debris flows and sediment-laden floods cause serious damage to human life and property. Effective measures require high-accuracy reproduction and prediction of runout distance (bed variation reach) via numerical simulations. One possible method to increase the accuracy of numerical simulation results involves reviewing the methods used to evaluate depositing rate for flows that contain many different sizes of sediments. This study performed experiments using an artificial channel and high-speed cameras to identify parameters that govern depositing rate. The channel implemented exhibited a change in slope point; thus, the slope of the upper reach differed from the slope of the lower reach. The experiments showed that the equation representing depositing rate is closely related to flow velocity. Additionally, the equation of depositing rate can be determined if other parameters are consistently considered.

The conversion of existing buildings to ZEB requires high thermal insulation. Vacuum insulation panels (VIPs) have a potential to be used for retrofitting thermal insulation of existing buildings from the viewpoint of low thermal conductivity, small thickness, and light weight. However, in order to realize vacuum insulation panels applicable to building insulation, it is necessary to overcome the challenge of maintaining the low pressure at which the high insulation performance can be achieved for several decades. The authors applied the double envelopes to VIPs and investigated longer service life of VIPs. The double envelope VIP is fabricated by fabricating a normal VIP, then wrapping the VIP with core materials, and then inserting it into the envelope for vacuum sealing. By applying the double envelopes, the pressure difference and the permeation of gas in inner VIP can be drastically reduced, resulting in a longer VIP lifetime. In this paper, the gas permeabilities of the gas barrier envelopes were experimentally estimated. Then, the pressure ageing in the double envelope VIP is calculated. The inner pressure after 25 years was 1.6 Pa for the envelope of aluminium composite film and 59.3 Pa for the envelope of transparent gas barrier film, indicating that long-term insulation performance could be improved. Next, the authors carried out acceleration test, in which the double envelope VIPs were put in a chamber at 80oC and remove once a month to measure the thermal conductivity. Even after 136 weeks, one sample showed only a 9.1% decrease in thermal resistance. From this result, it was confirmed that long-term insulation performance can be greatly improved by fabricating double envelope VIPs with the getter agent inside and the desiccant agent outside.

The notion that modern buildings should strive to be net-zero energy buildings (NZEBs) is widely accepted. In order to improve window’s insulation in existing buildings, structured-core transparent vacuum insulation panels (TVIPs) are proposed. TVIPs mainly consist of the structured core material, the low-emissivity film, and the transparent gas barrier envelope. TVIPs have high insulation performance and are inexpensive to manufacture and can be easily installed. However, it is necessary to overcome the issue of preventing the pressure rise inside TVIP after vacuum sealing. The authors constructed an experimental setup by applying the pressure-rate-of-rise-method to establish the fabrication process for TVIPs that prevents the pressure rise. In this experiment, a gas barrier film with a straw was used as the vacuum chamber. This could reproduce the pressure increase in the TVIP after sealing and the gas flow rate in the TVIP is evaluated. The experimental results showed that the internal pressure of TVIP could be reduced to about 1 Pa after vacuuming while heating for 8 hours, coating the core material, and sealing the getter material.

The conversion of existing buildings to ZEH and ZEB requires increased thermal insulation, in which the insulation of window surfaces is particularly important. This study focused on measuring and comparing the changes in thermal conductivity of transparent vacuum insulation panels (TVIP), which could be used as simple and easy to install insulation to building windows. These changes were later compared with the results obtained from previous studies conducted by other research group members. The measured thermal conductivity values ranged between 0.017 W/(m*K) of the best performing frame-type with the thickness of 5.1 mm, and 0.011 W/(m*K) of the best performing double-layered peak-type core with the thickness of 7.8 mm. The calculated U-values of the samples ranged between 4.1 W/(m2*K) and 1.4 W/(m2*K). From the experimental results it could be seen that changing the core composition had a larger effect on the overall thermal conductivity of the sample than the added parameters of coating, getter agent, and heating had. These parameters, however, have had a substantial effect on the longevity of the vacuum inside the sample envelopes, and will thus be experimented further.