Surface Modification of Fluorinated Polymers by Microwave Plasmas

We developed a new plasma treating method, incorporating the use of microwaves generated by an electronic cooking range. Using this method, polytetrafluorethylene (PTFE) and a copolymer of tetrafluoroethylene and hexafluoropropylene (FEP) were treated. Dialkylphthalates (DAP) were used as the standard liquids of contact angle measurements for evaluation of the wetting properties of plasma treated polymers. The components of surface tension (γ_L) due to the dispersion force (γ^d _L) and the polar force (γ^P _L) of DAP were calculated by Fowkes' equation from the contact angles (θ) on polypropylene. After plasma treatment cos θ of several standard liquids on PTFE and FEP increased. The linear relationship between γ_L(1 + cos θ)/(γ^d _L)^½ and (γ^P _L/γ^P _L)^½ was verified. γ_s and γ^d _s and γ^d _s of the plasma treated PTFE and FEP also increased. From the results of ESCA analysis, it was found that a significant amount of oxygen was introduced to the polymer surface by the plasma treatment. Peel strengths of a pressure sensitive adhesive bonded to PTFE and FEP increased approximately two-to threefold if the plasma treatment was used prior to bonding.     

Transmission electron microscopic observations of the multilevel microstructure of crosslinked copolymers with methacrylates and siloxane macromers by a radically polymerizable tuning approach

We investigated by Transmission Electron Microscopy (TEM) the morphologies of crosslinked copolymers from methacrylate monomers from methylmethacrylate (MMA) and trifluoroethylmethacrylate (TFEMA), polydimethylsiloxane (PDMS) macromers with molecular weight (Mn) of 1,700 and 4,700 g/mol, and crosslinker. Depending on the PDMS content, we observed, spherical PMMA islands in which small PDMS domains were dispersed, PMMA continuous phase, closely packed PTFEMA islands, and homogeneously dispersed PDMS domains were observed with low or middle magnification. Fine observation at 100,000‐fold magnification revealed the “fundamental” common size domain, which was determined by the M_n value of the PDMS macromer. Thus we found two microstructure types: (1) a “fundamental domain” due to the M_n of the PDMS macromer, and (2) an aggregated domain. The former was constant under all conditions, but the latter was affected by the comonomer and its ratio. The present results are essential in understanding the chemical and physical characteristics of crosslinked copolymers from PDMS macromers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Improving assurance of a sustainable route-split MANET routing by adapting node battery exhaustion

Assurance networks are designed to realize trustable Internet-Of-Things including terminal devices/infrastructure service applications for new generation networks. To construct assurance networks, it is necessary to evaluate them quantitatively. In this paper, we provide one of case studies to evaluate them quantitatively. In mobile ad hoc networks (MANETs), the network environments change over time due to the movement of nodes, the battery level of nodes, and so on. Assurance networks must maintain high performance even when such diverse changes of the network environments occur in the widely applicable domain. And if their performance degrades, they must early recover from the changes. So far, we have proposed a routing method for MANETs, called Route-Split Routing (RSR). RSR can suppress escalation of control packets in large scale MANETs. However, with RSR, drawbacks occur when some nodes exhaust their batteries. In this paper, we propose a sustainable route-split routing scheme to improve assurance by adapting node faults due to battery exhaustion for MANETs. To evaluate the assurance of the proposed method, we have implemented it with a simulator and have conducted simulation experiments. The results indicate that the proposed method can maintain high throughput when some nodes experience various levels of battery power and power consumption and even when some nodes die simultaneously.     

Three-dimensional collective flux pinning in the layered superconductor 2H-NbSe2-xSx

The collective pinning theory was compared with the results of flux pinning in the layered superconductor 2H-NbSe _2–x S _x.The size effect on the flux-pinning force and the angular dependence of the peak effect were investigated. Our sample did not show the size effect. Even when a magnetic field was applied parallel to the crystal layers, the peak effect was observed far below the zero-field critical temperature. These results show that flux pinning is three-dimensional within the frame of the collective pinning theory and that the peak effect is not caused by the dimensional crossover. The peak effect can be qualitatively explained in terms of the dispersion of the tilt modulus of the flux-line lattice.     

PREPARATIVE SEPARATION OF PROTEINS BY GRADIENT- AND STEPWISE-ELUTION CHROMATOGRAPHY: ZONE-SHARPENING EFFECT

A method is developed for predicting the zone-sharpening effect in linear gradient- and stepwise-elution chromatography of proteins. Numerical calculations have shown that the elution curve by different models are almost the same when the values of zone spreading parameters in the model are chosen so that the values of the number of the theoretical plates are equal. A good correlationship curve is established on the basis of the numerical calculations, from which the degree of the zone-sharpening can be easily predicted with a single dimensionless parameter.

When the modulator concentration is very high (the desorption is complete), the stepwise-elution chromatography can be regarded as the gradient elution with steep-slope of the gradient. The experimental stepwise elution cation-exchange chromatography of basic proteins from egg white has shown that the purity, the recovery and the concentration factor of the recovered fraction are very high.     

Performance of a protonated Co-contained silicate catalyst for NO reduction in equivalent conditions to diesel engine exhaust

Effects of co-existence of H₂O, CO₂, and SO₂ in the reaction gas on the catalytic performance of cobalt containing silicate having ZSM-5 (MFI) structure (Co-silicate) were studied. Water vapor retarded only the hydrocarbon conversion to CO₂ but no effect was observed on NO conversion. Addition of CO₂ or SO₂ did not affect the reaction. The stability of H-Co-silicate against H₂O, CO₂, and SO₂ was ascribed to the state of metallic active species which were stabilized by incorporation into the high siliceous MFI structure.     

Nano-scale chemical analyses of passivated surface layer on stainless steels

A surface analysis technique using scanning transmission electron microscopy (STEM) combined with a unique needle shape specimen is proposed. The unique needle shape specimen is effective to reduce matrix convolution as well as improve peak to background ratio of spectroscopy. To reveal the performance of the proposed technique, HNO₃ passivated surface layer on a type 436L ferritic and a type 304 austenitic stainless steels were analyzed. The results demonstrated that the proposed technique is able to quantify the distribution of alloying elements in the passivated surface layer approximately 3 nm in thickness, namely, the partitioning behaviour of alloying elements, i.e., Cr, Ni, Mo and Si in the passivated surface layer is revealed and agreed with that confirmed by Auger Electron Spectroscopy analysis. This proposed technique has potentialities for the analysis of nano scale local inhomogeneity, for example, pitting initiation process.     

Clinicopathological significance of Fhit protein expression in stage I non-small cell lung carcinoma

Abnormalities in structure and expression of the FHIT gene have been detected in a considerable fraction of primary lung tumors. Previous reports indicated that FHIT gene alterations can be simply detected by immunohistochemical methods. Therefore, we investigated the association of Fhit expression with clinicopathological features and allelic imbalance (AI) at the FHIT locus in 105 stage I non-small cell lung cancers (NSCLC) by the immunohistological method and PCR analysis. Thirty-six of 105 (34%) tumors showed marked reduction of Fhit immunoreactivity. Fhit expression was markedly reduced in most squamous cell carcinomas (24 of 28, 86%), whereas such a reduction was detected only in a small subset of adenocarcinomas (7 of 67, 10%; P < 0.001). A marked reduction of Fhit protein expression was observed more frequently in patients with a smoking history (32 of 80, 40%) than in patients without a smoking history (4 of 25, 16%; P = 0.013). These results indicate that FHIT gene alterations preferentially occur in squamous cell carcinomas and in smokers. Furthermore, a reduction of Fhit protein expression in tumor cells was associated with a poorer survival of patients with stage I NSCLC, irrespective of histological subtypes of tumors (P = 0.005; log-rank test). Fhit expression was reduced preferentially in tumors with AI at the FHIT locus; however, AI at the FHIT locus did not correlate with patients' survival (P = 0.262; log-rank test). These results suggested that Fhit protein expression could be a useful molecular marker for the prognosis of patients with surgically resected stage I NSCLC.     

超高数值孔径镜头面临的挑战

近来,关于浸没式光刻的讨论很多,不过它们大多集中在缺陷率和套刻精度上,而很少涉及到浸没式技术怎样使光刻机供应商具备设计与制造超高数值孔径镜头的能力,而这曾被认为是不可能实现的。尽管理论上折射式镜头能够扩展到很高的NA,但是由于受到材料和光刻机尺寸的限制,这种扩展并不现实。因此,要想研制超高NA的下一代镜头,必须采用截然不同的镜头设计。     

Clinical evaluation of cefozopran for infections associated with hematological malignancies

Cefozopran (CZOP) was used as an initial antibacterial therapy for infections in patients with hematological malignancies. CZOP was given at a daily dose of 4 g by drip intravenously to patients who were febrile over 38 degrees C and were suspected as having bacterial infections. As underlying diseases, 8 patients had acute lymphoblastic leukemia (ALL), 9 acute myeloblastic leukemia (AML), 2 aplastic anemia (AA), 2 adult T cell leukemia/lymphoma (ATLL), 28 non Hodgkin lymphoma (NHL), and 2 multiple myeloma (MM). Bacterial infections diagnosed were sepsis in 7 patients, suspected sepsis in 32, bronchitis in 6, pneumonia in 5 and acute peritonitis in 1. Clinical responses among 51 evaluable cases were excellent in 14, good in 15, fair in 3, poor in 19 and the overall response rate was 57%. The overall response rates for AML, ALL, AA, ATLL, NHL and MM were 56%, 63%, 100%, 50%, 50%, and 100%, respectively. Those for sepsis, suspected sepsis, bronchitis, pneumonia and acute peritonitis were 14%, 63%, 100%, 40%, and 0%, respectively. This therapy was effective in 53% (9/17) of patients whose granulocyte count remained below 500/microliter throughout the course of CZOP therapy. Six bacterial and one fungal strains were isolated from blood and sputum of six patients including five sepsis cases; two bacteria were eradicated and bacterial change was observed in one case. As side adverse effects, 10 patients had liver dysfunction, 1 anemia, 2 proteinemia, 1 indirect bilirubinemia, 2 thrombocytopenia, and 1 eosinophilia. We tried to establish a scoring system for the severities of patients with their infections, underlying diseases, treatments for the underlying disease, and granulocyte counts in order to evaluate the efficacy of CZOP more precisely. This scoring system was consisted of three grades; severe, moderate, and mild. CZOP was effective on mild and moderate grades. These results indicate that the initial antibacterial therapy by CZOP is useful for the treatment of mild and moderate grade infections complicated with hematological malignancies.