Synthesis of calcium phosphate hydrogel from waste incineration fly ash and bone powder

Waste incineration fly ash and bone powder could be successfully recycled into calcium phosphate hydrogel, a type of fast proton conductor. Various properties of the intermediate and calcium phosphate hydrogel from them were characterized and compared with that from calcium carbonate reagent. It was found that the intermediate from the incineration fly ash and calcium phosphate glass was more brittle than that from bone powder and calcium carbonate reagent. The electric conductivity of crystallized hydrogel obtained from all raw materials increases exponentially with temperature. However, the crystallized hydrogel from incineration fly ash has lower electric conductivity and lower crystallinity than that from bone powder and the reagent. Moreover, the difference in electric conductivity between these crystallized hydrogels decreases with temperature. Compared with using the reagent as a raw material, bone powder provides a 25% reduction in the usage of H(3)PO(4) to acquire the crystallized hydrogel which has the highest conductivity. These experimental results suggest that the incineration fly ash and bone powder are useful calcium sources for the synthesis of calcium phosphate hydrogel.     

Enhanced in vivo responses of osteoblasts in electrostatically activated zones by hydroxyapatite electrets

Matured osteoblasts were proved to be located in the bone formation accelerated by induced large surface charges on the electrically polarized hydroxyapatite (HA) ceramics regardless of the charge polarities, whereas the spatial cell distribution patterns were different. Polarized HA ceramic plates with an average electric charge of 3.9 μCcm⁻² were implanted in widely spaced defects of canine femora for 3 and 7 days. The osteoblasts were identified by immunochemical detections of osteocalcin and osteopontin. Expressions of osteocalcin and osteopontin were detected throughout the gaps between the implanted HA plates and the cut cortical bone surfaces, especially in the vicinities of the cut cortical bone surfaces and the osteoids regardless of the polarity of the induced charges. Additionally, the newly formed bone tissue that directly bonded to the negatively charged HA surfaces was lined by an osteoblast layer. As soon as 7 days after the implantation, the presence of well-developed osteoblasts suggested that the electrostatic force of the HA ceramics had conditioned the field in the biointerface zone of the polarized HA surfaces.     

TiCrVMo alloys with high dissociation pressure for high-pressure MH tank

High-pressure metal hydride (MH) tank is a possible hydrogen storage system for fuel cell vehicles. The merit of the high-pressure MH tank system is improved by the use of a metal hydride with high dissociation pressure. In this study, TiCrV and TiCrVMo alloys with BCC structure has been developed for the high-pressure MH tank system. The developed TiCrVMo alloy shows 2.4 mass% of effective hydrogen capacity between 0.1 MPa and 33 MPa at 298 K, which has a dissociation pressure of 2.3 MPa at 298 K. By investigating the dissociation pressures of the synthesized metal hydrides, it is found that Mo has a special effect to increase dissociation pressure of the metal hydrides. This effect is probably attributed to the large bulk modulus of Mo compared to other elements.     

The relationship between AE and dissipation energy for fretting wear

This paper describes the behavior of acoustic emission (AE), especially the correlation between the AE output and the dissipation energy under the fretting conditions. Fretting tests are conducted with a ball contacting with a flat disc in air. The specimens used are a bearing steel for a ball, and a bearing steel or an aluminum alloy for a flat disc. The results show that the behavior of the AE output and the dissipation energy during each fretting cycle is not so similar to each other throughout the test, but the total AE root-mean-square and the total dissipated energy during the test have a good correlation between them.     

Evaluation of pharmaceuticals and personal care products as water-soluble molecular markers of sewage

We examined the utility of 13 pharmaceuticals and personal care products (PPCPs) as molecular markers of sewage contamination in riverine, groundwater, and coastal environments. The PPCPs were crotamiton, ibuprofen, naproxen, ketoprofen, fenoprofen, mefenamic acid, thymol, triclosan, propyphenazone, carbamazepine, diethyltoluamide, ethenzamide, and caffeine. Measurements in 37 Japanese rivers showed positive correlations of riverine flux of crotamiton (r2 = 0.85), carbamazepine (r2 = 0.84), ibuprofen (r2 = 0.73), and mefenamic acid (r2 = 0.67) with the population in the catchments. In three surveys in the Tamagawa estuary, crotamiton, carbamazepine, and mefenamic acid behaved conservatively across seasons within a salinity range of 0.4-29 per thousand, suggesting their utility as molecular markers in coastal environments. Removal of ketoprofen and naproxen in the estuary was ascribed to photodegradation. Ibuprofen and thymol were removed from estuarine waters in summer by microbial degradation. Triclosan was removed by a combination of microbial degradation, photodegradation, and adsorption. These results were consistent with those of river water incubated for 8 d at 25 degrees C in the dark in order to examine the effects of biodegradation and photodegradation. Crotamiton was detected in groundwater from the Tokyo metropolitan area (12 out of 14 samples), suggesting wastewater leakage from decrepit sewers. Carbamazepine, ketoprofen, and ibuprofen (5/14), caffeine (4/14), and diethyltoluamide (3/14) were also detected in the groundwater, whereas the other carboxylic and phenolic PPCPs were not detected and were thought to be removed during their passage through soil. All the data demonstrated the utility of crotamiton and carbamazepine as conservative markers in freshwater and coastal environments. We recommend combining these conservative markers with labile PPCPs to detect inputs of poorly treated sewage.     

Thioamide-Bridged Nucleic Acid (thioAmNA) Containing Thymine or 2-Thiothymine: Duplex-Forming Ability,Base Discrimination,and Enzymatic Stability

Oligonucleotides containing bridged nucleic acids (BNAs) show high duplex-forming ability towards target single-stranded RNA, so many BNAs have been developed for antisense applications. Amide-bridged nucleic acids (AmNAs), which are BNA analogues bearing an amide bond at the bridge, exhibit high duplex-forming ability, enzymatic stability, and antisense activity; thus, the AmNA motif represents a promising BNA scaffold. The high enzymatic stability of the AmNA motif is presumably attributable to the bulky amide structure, because it inhibits the access of nucleases to the phosphodiester linkage. Here, to improve enzymatic stability further, we designed thioAmNAs: thioamide-bridged nucleotides that have a bulkier bridge structure than AmNA. The synthesis of thioAmNAs bearing either thymine (thioAmNA-T) or 2-thiothymine (thioAmNA-S²T) bases was successful, and the obtained monomers were introduced into designed oligonucleotides without noticeable by-product generation. The thioAmNA-T- and thioAmNA-S²T-modified oligonucleotides showed strong binding affinity toward complementary single-stranded RNA, with the thioAmNA-S²T-modified oligonucleotide displaying excellent base-discrimination capability. Moreover, both thioAmNA-T and thioAmNA-S²T endowed oligonucleotides with higher resistance to enzymatic degradation than AmNA-T. These results indicate that thioAmNAs are potentially useful chemical modifications for oligonucleotide-based therapeutics.     

醋酸菌对C57BL/6J小鼠的酒精性肝损伤的影响研究

该文针对摄入醋酸菌对于酒精性肝损伤的影响进行了评价。将C57BL/6J小鼠（8周龄,雄性,22～27 g）分为对照组（非乙醇给药组）、乙醇组（给予2.5 g/kg乙醇）、乙醇+醋酸菌组（给予2.5 g/kg乙醇+10 mg醋酸菌）,分别每天给药3次,连续经口给药14 d,测定了血清谷草转氨酶（AST）、谷丙转氨酶（ALT）及肝脏油脂浓度。结果表明,与对照组相比较,乙醇组小鼠的AST与ALT浓度,肝脏甘油三酯与胆固醇浓度显著增高（P＜0.05）;乙醇+醋酸菌组的数值则显著低于乙醇组（P＜0.05）。以上结果表明,摄入醋酸菌有可能会减轻酒精性肝损伤。     

Sound insulation of walls using wood insulation mat and plywood jointed with a combination of adhesive tape and wood dowels

In this study sound insulation of walls was evaluated using wood insulation mat and plywood jointed with a combination of adhesive tape and wood dowels. Building of actual wall assembly test specimens and evaluating their sound insulation revealed that the sound transmission loss for jointing using a combination of adhesive tape and wood dowels was considerably higher than that using nails, for middle and high frequency ranges of 2 kHz and above. When comparing heat-insulating materials (sound-absorbing materials), the test specimen using high-density glass wool had greater sound insulation than the specimen using low-density materials, and the specimen using wooden heat-insulating/sound-absorbing materials showed roughly the same properties as glass wool of 20 % higher density. When the sound insulation for impact sounds of the experimental specimen (joined with adhesive tape and using wooden heat-insulating/sound-absorbing materials) was compared to a specimen with a typical composition (joined with nails and using glass wool), the former proved to have better sound insulation, by approximately 10 dB for light impact sounds between 400 and 800 Hz and approximately 5 dB for higher frequencies. For heavy impact sounds, the experimental specimen displayed a greater sound insulation for all frequencies, by 5–10 dB at frequencies of around 100 Hz and of 400 Hz and above.     

Effect of metal ion location in reaction medium on formation process and structure of PtCu–CuO nanoparticles supported on carbon and γ-Fe2O3

The process of nanoparticle formation by radiochemical synthesis in a heterogeneous system has been investigated considering the effects of the metal ion location in the reaction medium. PtCu nanoparticles supported on carbon and γ-Fe₂O₃ were synthesized using a high-energy electron beam. The metal ions in the precursor were categorized as those dissolved in solution, adsorbed on support, and precipitated. The ratio of metal ions in the solution was varied prior to the electron beam irradiation and its effects on the synthesized particle structures were examined. The nanoparticles were characterized by inductively coupled plasma-atomic emission spectrometry, transmission electron microscopy, X-ray diffraction, and X-ray absorption spectroscopy. A PtCu alloy and CuO were immobilized on the support in all the samples. The PtCu alloy nanoparticle composition depended on the Cu ion content in the solution. The nanoparticle formation mechanism could be explained using the obtained results. Metal ions present in the solution resulted in formation of the alloy. The adsorbed ions also contributed to the alloy formation by desorbing from the support when irradiated. On the other hand, alloy formation with Pt from the precipitated Cu ions was found to be difficult.     

Laboratory study and interpretation of mechanical behavior of frozen clay through state concept

Towards the development of a mechanical model that can be part of multi-physical analysis of frozen soils, a program of systematic frozen-unfrozen parallel triaxial tests at different temperatures and strain rates was conducted. The mechanical behavior of the reconstituted high-plasticity clay samples was investigated and interpreted through a state concept based on Ladanyi and Morel’s (1990) postulate on the unique relationship between the inter-particle “effective” stress and the strain path. The Critical State Lines (CSLs) for clay specimens frozen undrained were mapped by referring to the shear behavior of unfrozen specimens sharing the same strain history. With other conditions set identical, the shear strength linearly increased with a decrease in the temperature for the range from ?10 °C to ?2 °C, and log-linearly increased with an increase in the strain rate for the range from 0.001%/min to 0.1%/min. Direct comparison of the strain-rate effects between frozen and unfrozen specimens with identical strain paths and states in the soil skeleton clearly indicates that the viscoplasticity derives from that of pore ice. A conceptual interpretative framework invoking temperature- and strain rate-dependent state bounding surfaces and CSLs was proposed to describe the behavior of frozen soils under steady and non-steady temperature and strain rate. The above observations of the behavioral features of frozen and unfrozen soils, with further experimental work, are expected to lead to the construction of a unified framework for describing the behavior under both states and the transition between them.