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Three new isopimaric acid diterpenoids, 6-oxoisopimaric acid (1), 6α-hydroxyisopimaric acid (2), and isopimara-7,9(11),15-trien-18-oic acid (4), together with two known isopimaric acid diterpenoids, isopimaric acid (3), and 8(14),15-isopimaradien-18-oic acid (5), were isolated from the bark of Cryptomeria japonica D. Don. Their structures were determined by analysis of spectroscopic data and comparison with the spectral data of known analogues. At the concentration of 50 μM, compounds 1–5 inhibited xanthine oxidase activity by 17.3, 16.5, 2.6, 30.5, and 24.5 %, respectively.

A new seco-abietanoid, 12-hydroxy-6,7-seco-abieta-8,11,13-triene-6,7-dioic acid (1), was isolated from the methanol extract of the bark of Cryptomeria japonica. The structure was established by spectroscopic analyses including 1D and 2D NMR (1H, 13C, COSY, HMQC, HMBC, and NOESY) and EI-MS and comparison with the data of known analogues.

Two new dimeric abietane-type diterpenoids, 12-hydroxyabieta-8,11,13-trien-7-α-yl 7-oxoabieta-8,11,13-trien-12-yl peroxide (trivial name japonicinol C, 1) and 12-hydroxyabieta-8,11,13-trien-7-α-yl 7-oxoabieta-5,8,11,13-tetraen-12-yl peroxide (trivial name japonicinol D, 3), together with two known dimeric abietane-type diterpenoids, obtusanol A (2) and 7-α-(2-butoxyethoxy)-12-hydroxyabieta-6-yl 6,7-dehydroabieta-8,11,13-trien-12-yl ether (4), were isolated from the methanol extract of the bark of Cryptomeria japonica. Their structures were established by mean of spectroscopic analysis and comparison of NMR data with those of known analogues. At a concentration of 50 μM, compounds 1–4 inhibited xanthine oxidase activity by 29.8, 39.3, 27.1, and 14.7 %, respectively. In addition, compounds 1 and 4 also showed 13.9 and 20.5 % inhibition toward angiotensin-converting enzyme (ACE), respectively.

Two new dimeric abietane-type diterpenoids, 12-hydroxyabieta-8,11,13-trien-7α-yl 7β-hydroxyisopimara-8(14),15-diene-18-peroxoate (trivial name japonicinol A, 1) and 6α,7α-O-(7,8-secoabieta-9(11),13-diene-8,12-dioxo-7-ylidene)ferruginol (trivial name japonicinol B, 3), together with three known dimeric abietane-type diterpenoids, sugikurojin J (2), sugikurojin B (4) and formosaninol (5), were isolated from the bark of Cryptomeria japonica D. Don. Structure elucidation was accomplished by spectroscopic methods, mainly 1D and 2D NMR and HREIMS, as well as by comparison of their NMR data with those of related known analogues. At the concentration of 50 μM, compounds 1–5 inhibited xanthine oxidase activity by 31.3, 23.4, 18.7, 17.3 and 24.4%, respectively. In addition, compound 4 also inhibited angiotensin-converting enzyme (ACE) activity by 19.2%.

Three new 7-oxoabietane-type diterpenoids, 3-oxosugiol methyl ether (1), 18-hydroxysugiol (2), and 1β-hydroxysugiol (3), as well as two known 7-oxoabietane-type diterpenoids, 6α-hydroxysugiol (4) and 6α-acetoxysugiol (5), were isolated from the bark of Cryptomeria japonica D. Don. Their structures were elucidated mainly by NMR and HREIMS, as well as on comparison with the data of known analogues. At the concentration of 75 μM, compounds 2 and 5 exhibited 11.9 and 21.7% xanthine oxidase inhibitory activity, respectively.

A mechanically coupled array technique to enable a fully differential operation of single-crystal silicon thermal-piezoresistive resonators (TPRs) has been demonstrated to alleviate resistive feedthrough issues often seen in TPRs, therefore, featuring clear resonance behavior with decent signal-to-feedthrough ratio. The proposed thermal-piezoresistive dual-II-BARs exhibits feedthrough reduction of more than 67 dB, and no spurious mode, is found within a wide frequency span. The resonator array together with board-level sustaining circuitry also works as a thermal-piezoresistive oscillator (TPO) and demonstrated its performances for real-time mass sensing. Finally, the proposed TPO mass sensor possesses several key features, including real-time monitoring, fast response time, and most importantly, excellent mass resolution of only 83 fg extracted from the measured TPO’s Allan deviation. [2017-0085]

Two new sesquarterpenoids, i.e. ferrugicadinol A (1) and ferrugicryptomeridiol (3), and one known sesquarterpenoid, ferrugicadinol (2) were isolated from the bark of Cryptomeria japonica D. Don. Their structures were identified by extensive spectral analysis and comparison with the data of known analogues.

Angiostrongylus cantonensis is a metastrongyloid nematode that causes eosinophilic meningoencephalitis in humans. A high infestation of A. cantonensis can cause permanent brain damage or even death. The inflammasome is an oligomeric molecular platform that can detect microbial pathogens and activate inflammatory cytokines. The recognition of larval surface antigens by pattern recognition receptors (PRRs) can cause oligomerization of the NOD-like receptor (NLR) or absent in melanoma 2 (AIM2) with the adaptor apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) to form a caspase-1-activating scaffold. Activated caspase-1 converts pro-inflammatory cytokines into their mature, active forms. Helminths infection has been shown to activate NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasomes. In this study, we aimed to investigate the mechanism of inflammasome activation upon A. cantonensis infection in a mouse model. This study provides evidence that A. cantonensis infection can activate NLRP1B and NLRC4 inflammasomes and promote pyroptosis to cause meningoencephalitis.

Three new dimeric abietane-type diterpenoids, abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7&alpha, yl peroxide (1), abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7&beta, yl peroxide (2), and 12-hydroxyabieta-8,11,13-trien-7&beta, yl 7-oxoabieta-5,8,11,13-tetraen-12-yl peroxide (3), together with four known abietane-type diterpenoids (4&ndash, 7) were isolated from the methanol extract of the bark of Cryptomeria japonica. Their structures were elucidated on the basis of spectroscopic analysis and comparison of NMR data with those of known analogues. At a concentration of 50 &mu, M, compounds 1, 2, and 3 showed 26.2%, 23.6%, and 35.7% inhibition towards xanthine oxidase enzyme, respectively. In addition, compound 3 also showed 24.9% inhibition toward angiotensin-converting enzyme (ACE).

Three new abietane-type diterpenoids, 7α-butoxyabieta-8,12-diene-11,14-dione ( 1 ), 6α,7α-dihydroxyabieta-8,12-dien-11,14-dione ( 2 ), and 6α,7β-dihydroxyabieta- 8,12-diene-11,14-dione ( 3 ) were isolated from the bark of Cryptomeria japonica D. Don. Their structures were established by means of 1D and 2D NMR, IR, UV, and HR-EI-MS spectra and comparison with the data of known analogues.

Three new abietane-type diterpenoids, 7β-acetoxy-12-methoxyabieta-8,11,13-triene-6α,11-diol (1), 7α-acetoxy-12-methoxyabieta-8,11,13-triene-6α,11-diol (2), and 6α-acetoxy-12-methoxyabieta-8,11,13-triene-7α,11-diol (3), as well as two known abietane-type diterpenoids, 12-methoxyabieta-8,11,13-triene-6α,7β,11-triol (4) and 6α-acetoxy-12-methoxyabieta-8,11,13-triene-7β,11-diol (5), were isolated from the MeOH extract of the bark of Cryptomeria japonica. Their structures were determined by analysis of spectroscopic data and comparison of NMR data with those of related metabolites.

Thyroid orbitopathy (TO) is a multi-system inflammatory disease characterized by orbital congestion, ocular surface disorders, restrictive myopathy, and skin lesions. The molecular and cellular processes of pathogenic formation of TO orbital fat tissues are not fully understood. In this study, a comparative proteomic analysis was conducted to investigate the importance of some differential proteins of orbital fat tissues in TO. The differential proteins were analyzed by comparing the two-dimensional gel electrophoresis (2-DE) maps of the orbital fat tissues of TO with those of normal orbital fat tissues. The 2-DE results were further verified by Western blot and immunohistochemistry. Fifteen up-regulated and two down-regulated proteins in TO orbital fat tissues in comparison with the control were exhibited by 2-DE maps. The over-expressed proteins including guanine nucleotide-binding protein, isocitrate dehydrogenase (IDH), annexin A2, heat shock protein 60 (HSP 60), calreticulin (CALR), protein disulfide-isomerase A3 (PDIA3), spectrin, superoxide dismutase (SOD), and transitional endoplasmic reticulum ATPase (TER ATPase) may contribute to increased thyroid-stimulating hormone receptor (TSHR) expression and cell proliferation. The proteomic data of specific proteins are consistent with those determined by Western blot and immunohistochemistry. Comparison of orbital fat proteins from thyroid orbitopathy with age-matched controls shows significant differences in the proteome, and up-regulations of the specific proteins in orbital fat tissues from TO are associated with biochemical mechanisms or capacities against endoplasmic reticulum stress, mitochondria dysfunction, and cell proliferation as well as apoptosis in TO orbital fat tissues.

A real-time temperature compensation method using resistance control with two-point calibration, implemented in a CMOS-MEMS thermal-piezoresistive oscillator (TPO), has been demonstrated in this work. To enhance the thermal stability of the CMOS-MEMS TPO for future mass/aerosol sensing applications, a novel algorithm is proposed to attain a temperature coefficient of frequency (TCF) of only −0.5 ppm/°C which is 66 times improvement over uncompensated case. The implemented TPO has no passive compensation as the structure is made of CMOS back end oxide and polysilicon to obtain a high quality factor (Q) of 2,000 in air. The heater resistance serves as ambient temperature sensor. As a result, the proposed method only requires measurement at two temperature points to modify the controlled resistance of the heater and is much more convenient than other low TCF methods utilizing look-up table (LUT) or polynomial equation fit.

Three new abietane-type diterpenoids, 7β-acetoxy-12-methoxyabieta-8,11,13-triene-6α,11-diol (1), 7α-acetoxy-12-methoxyabieta-8,11,13-triene-6α,11-diol (2), and 6α-acetoxy-12-methoxyabieta-8,11,13-triene-7α,11-diol (3), as well as two known abietane-type diterpenoids, 12-methoxyabieta-8,11,13-triene-6α,7β,11-triol (4) and 6α-acetoxy-12-methoxyabieta-8,11,13-triene-7β,11-diol (5), were isolated from the MeOH extract of the bark of Cryptomeria japonica. Their structures were determined by analysis of spectroscopic data and comparison of NMR data with those of related metabolites.

We report a thermally driven and piezoresistively sensed CMOS-microelectromechanical systems (MEMS) resonator with quality factor $Q >10$ 000 and stopband rejection of 15 dB under CMOS-compatible bias voltage. The bias voltage requirement of this letter is two orders of magnitude lower than that of the previous CMOS-MEMS capacitively transduced resonators. In addition, the combination of the bulk-mode resonator design and high- $Q$ SiO2/polysilicon structural material leads to resonator $Q >10$ 000, a key index for low-phase-noise oscillators and low-insertion-loss filters. The resonator with a center frequency at 5.1 MHz was fabricated using a standard 0.35 $\mu $ m 2-poly-4-metal CMOS process, featuring low cost, batch production, fast turnaround time, easy prototyping, and MEMS/IC integration. To resolve the feedthrough issue often seen in conventional thermal-piezoresistive resonators: 1) separation of the heater and piezoresistor is first adopted because of the routing flexibility of the structural configuration offered by CMOS back-end-of-line materials and 2) fully differential measurement scheme is then applied to the proposed device, both of which enable a low-feedthrough level with 65-dB improvement as compared with its single-ended counterpart.

Active compounds from natural products have been widely studied. The anti-tumor effects of 13-acetoxysarcocrassolide isolated from Formosan soft coral Sarcophyton crassocaule on bladder cancer cells were examined in this study. An MTT assay showed that 13-acetoxysarcocrassolide was cytotoxic to bladder female transitional cancer (BFTC) cells. We determined that the BFTC cells underwent cell death through apoptosis by flow cytometry. Due to the highly-migratory nature of the BFTC cells, the ability of 13-acetoxysarcocrassolide to stop their migration was assessed by a wound healing assay. To determine which proteins were affected in the BFTC cells upon treatment, a comparative proteomic analysis was performed. By LC-MS/MS analysis, we identified that 19 proteins were up-regulated and eight were down-regulated. Seven of the proteins were confirmed by western blotting analysis. This study reveals clues to the potential mechanism of the cytotoxic effects of 13-acetoxysarcocrassolide on BFTC cells. Moreover, it suggests that PPT1 and hnRNP F could be new biomarkers for bladder cancer. The results of this study are also helpful for the diagnosis, progression monitoring and therapeutic strategies of transitional cell tumors.

Two new abietane-type diterpenoids, 15-hydroxy-12- O-methylsugiol (1) and 2a-hydroxy-12- O-methylsugiol (2) were isolated from the methanol extract of the bark of Cryptomeria japonica. Their structures were elucidated on the basis of spectroscopic analysis and comparison of NMR data with those of known analogues. Compounds 2 showed 13.5% inhibition towards xanthine oxidase enzyme at the concentration of 75 μM

The different molar ratios of collagen/chitosan were used to be immobilized on polypropylene nonwoven fabrics grafted with N-isopropyl acrylamide (abbr. PP-g-NIPAAm-i-Col/Chi). For a controlled immobilizing time and NIPAAm concentration, the collagen/chitosan immobilized values and the antibacterial properties of PP-g-NIPAAm-i-Col/Chi increased with increasing amount of chitosan in the mixture of collagen/chitosan. The crosslinking reaction between the grafted polyNIPAAm and collagen/chitosan molecules was clearly confirmed by the examination of the spectra of the surface reflection infrared spectroscopy (IR). The values of water absorption and water diffusion coefficient of PP-g-NIPAAm-i-Col/Chi decreased with increase of the chitosan in the mixture of collagen/chitosan and the value of immobilized collagen/chitosan at the same pH value of buffering water. The PP-g-NIPAAm-i-Col/Chi have excellent water absorption, water permeability, and antibacterial properties and would be suitable for the healing of wounded skin area.

A novel method for preparing polyurethane/nano-clay composites was used in this study. The nano-clay was pre-mixed with the various components, such as diphenylmethane diisocyanate (MDI), 2,2-bis(hydroxymethyl) propionic acid (DMPA) or polytetramethyleneglycol (PTMG), of polyurethane (PU) polymer to prepare the composites. The PU/clay composites prepared by this method revealed that the values of the tensile strength at break, the elongation at break, the modulus and the surface roughness for the composite prepared from the pre-mixture of clay and PTMG (PU/clay-PTMG composite) were higher than those for the composite prepared from the pre-mixture of clay and MDI (PU/clay-MDI composite), the composite prepared from the pre-mixture of clay and DMPA (PU/clay-DMPA composite) and PU. The thickness of the crystals for PU/clay-MDI and PU/clay-DMPA composites was larger than that for PU and PU/clay-PTMG; whereas the layer distance of the crystals for PU/clay-MDI and PU/clay-DMPA composites was smaller than those for PU and PU/clay-PTMG. The values of glass transition temperature (Tg) of soft and hard segments were in the order of PU/clay-MDI > PU/clay-DMPA > PU > PU/clay-PTMG. Among the three PU/clay composites prepared by the pre-mixing procedure, PU/clay-MDI and PU/clay-DMPA composites showed significant gathering of the nano-clay in the PU matrix. A possible mechanism of the structural changes under tensile stress was speculated to explain the reason for the higher tensile strength and elongation at break of PU/clay-PTMG composite. The pre-mixing of clay-PTMG was a good procedure for the manufacture of the PU/clay composite, which had higher values of tensile strength and elongation at break.

A novel C(35)-terpene, designated as cryptotrione (1), with an unprecedented skeleton possessing an abietane diterpene with a unique bicyclic sesquiterpene, is identified from the bark of Cryptomeria japonica. The carbon skeleton of 1 represents a new structural entity, and this is an intriguing addition to the structurally diverse diterpene-sesquiterpene class. A unique biosynthetic pathway is proposed to support the production of this phytocompound. Notably, 1 exhibits anticancer activity with an IC(50) value of 6.44 +/- 2.23 microM.

In this study, helium/oxygen/nitrogen (He/O2/N2)-plasma was used to etch/modify the surface of ultra-high-molecular-weight polyethylene (UHMWPE) fiber. After coated with polyurethane (PU), the plasma treated UHMWPE fabrics were laminated. It was found that the values of peeling strength between the laminated UHMWPE fabrics treated with He/O2/N2-plasma were significantly higher (3–4 times) than that between pristine fabrics. The hydrophilic property and the value of the surface roughness of the UHMWPE fibers increased significantly after treated with He/O2/N2-plasma. The mechanism of the oxidation/degradation of the polymers on the surface of the UHMWPE fiber during He/O2/N2-plasma treatment was suggested. In addition, it was found that the higher content of functional groups (carbonyl, aldehyde, and carboxylic acid) on fiber surface and the higher value of surface roughness of the UHMWPE fiber treated with He/O2/N2-plasma could significantly improve the adhesion-strength of the laminated UHMWPE fabric. Especially, the micro-aperture on the surface of UHMWPE fiber caused by the strenuous etching of He/O2/N2-plasma treatment was also an important factor on improving the adhesion-strength between the laminated UHMWPE fabrics. Copyright © 2010 John Wiley & Sons, Ltd.

In this study, argon plasma treatment was added to the traditional pad-dry-cure process between dry and cure treatment. This new process was assign as pad-dry-plasma-cure. The crosslinking agent was a mixture of dimethyloldihydroxyethyleneurea (DMDHEU) and acrylic acid (AA). The results showed that argon plasma treatment could increase the bonded crosslinking agent (nitrogen content). Dry crease recovery angle (DCRA), wet crease recovery angle (WCRA) and tensile strength retention (TSR) of pad-dry-plasma-cure-finished fabrics were higher than that of traditional pad-dry-cure finished fabrics at a given value of nitrogen content. Additionally, it was found that the number of crosslinks per anhydroglucose unit (CL/AGU) and the length of crosslinks of pad-dry-plasma-cure-finished fabrics were higher than that of traditional pad-dry-cure-finished fabrics at a same resin concentration in the pad bath. DCRA, WCRA and TSR values of pad-dry-plasma-cure-finished fabrics were higher than that of pad-dry-cure-finished fabrics at a same CL/AGU value. The pad-dry-plasma-cure process is thought to be excellent for improving the physical properties and decreasing the formaldehyde release of the finished cotton fabrics.

In this study, two bacteria and three odorous chemicals were employed to assess the antibacterial activity and the odor elimination abilities of fabric samples finished with nanometer titanium dioxide/nanometer silver/water-borne polyurethane (nano-TiO2/nano-Ag/WBPU) composite emulsions. It was found that the value of odor elimination, ultraviolet light transmission, and anti-bacteria for the mixture of nano-TiO2 and nano-Ag was higher than the summed value for the individual nanoTiO2 and nano-Ag. The odor elimination ability for individual nano-TiO2 was better than that for individual nano-Ag, but the anti-bacterial activity was found to follow the opposite trend. The mechanisms of the free radical formation for nano-TiO2Ag+ have been discussed, suggested and confirmed with the investigation of the energy gap and conductivity values for the individual and the mixed particles of nano-TiO2 and nano-Ag. The loss of the anti-bacterial activity for the fabrics finished with the mixture of nano-TiO2 and nano-Ag was less than 6% and 13% after 15 times’ washing and 3000 times’ abrasion, respectively. The practicability of the fabrics finished with nano-TiO2/nanoAg/WBPU composite emulsions was strongly supported by the excellent properties of odor elimination, anti-bacteria, washing fastness and abrasion resistance.

The wound dressing of acrylic acid-grafted and gamma-polyglutamic acid/chitosan-immobilized polypropylene non-woven fabric (PP-AAg-PGCi) was produced in this study. Gamma-polyglutamic acid (gamma-PGA) was first applied in this field to composed with chitosan. The PP-AAg-PGCi wound dressings were expected to enhance the water absorbing, water permeating and wound healing properties. The results showed that the immobilizing percentage, water absorbing value and water diffusion coefficient for PP-AAg-PGCi samples increased with the increase of the gamma-PGA in the immobilizing bath; whereas, decreased with the increase of the chitosan in the immobilizing bath. The immobilized chitosan was aggregating with the state of discontinuous and uneven mass materials on the surface of the immobilized gamma-PGA. The water absorbing, water permeating, and anti-bacterial properties of the PP-AAg-PGCi samples were much better than that of AA grafted and collagen/chitosan immobilized PP non-woven sample (PP-AAg-CCi) in our previous study. Anti-bacterial property for PP-AAg-PGCi samples was excellent. The effect on accelerating wound healing for PP-AAg-PGCi samples was strong. The product of the multi-layer material of PP-AAg-PGCi was expected to bestow better services for wound dressing.

The wound dressing of acrylic acid-grafted and chitosan/collagen-immobilized polypropylene non-woven fabric (PP–AAg–CCi) were produced. In this study, two kinds of chitosan obtained from the nourishment of Mucor (m-chitosan) and from commerce (c-chitosan) were used for comparison. It was found that the values of water absorbing and water diffusion coefficient for m-chitosan sample (PP–AAg–CmCi) were significantly higher than that for c-chitosan sample (PP–AAg–CcCi). The enhanced percentage on water absorbing value and water diffusion coefficient for PP–AAg–CmCi sample increased with the increasing of chitosan contained in the mixture of chitosan/collagen. The surface of the PP–AAg–CcCi sample was smooth; however, the surface of the PP–AAg–CmCi sample was rough and cracky/loose. The higher water adsorption and water diffusion properties were caused by the nature of agent for the PP–AAg–CmCi sample. The hydroxyl group contained on m-chitosan, which was prepared in this study, was higher than that contained on c-chitosan. The anti-bacterial properties of the PP–AAg–CmCi and PP–AAg–CcCi samples were all excellent. The products of the multi-layer material of PP–AAg–CmCi were expected to provide better services for wound dressing.

In this study, diphenylmethane diisocyanate (MDI), 2,2-bis(hydroxymethy)-propionic acid (DMPA), and polytetramethyleneglycol (PTMG) were employed to polymerize the low molecular weight polyurethane (LMWPU). The mole ratios for the LMWPUs were 4.0:1.5:0.5, 4.0:1.0:1.0, and 4.0:0.5:1.5, respectively. The three LMWPUs were dissolved in lithium chloride/tetrahydrofuran (UCV THF) to prepare the finishing solutions. The water retaining values of the treated non-woven fabrics with the solutions increased by the increase of the component of the PTMG contained in LMWPU. This higher content of PTMG in LMWPU resulted in a lower add-on value and a lower degree of the blocking deposited in the gaps among fibers. Both of these could significantly improve the water retaining property. The water retaining values for the LMWPU solutions were dramatically higher than those for commercial water soluble polyurethane and LMWPU emulsions. The functional groups of LMWPU were confirmed with the analyses of the spectra of Fourier transform infrared spectroscopy (FT-IR). The average molecular weights of the three LMMTUs ranged from 2000 to 3800 g/mole and the average particle sizes ranged from 140 to 1140 nm. The degree of polymer crystals obtained from LMWPU solutions is lower, which could also significantly improve the water retaining property.

In this study, the effect of argon-plasma treatment on the grafting of methyl diallyl ammonium salt (MDAA) onto polyamide-6 film and the anti-bacterial and surface properties of the plasma- and graft-treated film were investigated. The grafting amounts of MDAA caused by argon-plasma treatment increased with the increase in the plasma exposure time and plasma power. The analyses of Fourier transform infrared (FT-IR) spectroscopy and electron spectroscopy for chemical analysis (ESCA) spectra revealed that the epoxy and vinyl groups of MDAA could be grafted on the argon-plasma treated polyamide-6 film. The survey spectra of ESCA, the patterns of atomic force microscopy (AFM), and the spectra from scanning electron microscopy (SEM) were employed to certify the surface modification of argon-plasma treated and the argon-plasma treated/MDAA grafted polyamide-6 films. Argon-plasma treatment could generate the functional group and increase the roughness on the surface of polyamide-6 film. This phenomenon could enhance the grafting effect of MDAA. The anti-bacterial property of argon-plasma treated/MDAA grafted polyamide-6 film was excellent. This argon-plasma treated/MDAA grafted polyamide-6 film was expected to be applied on the field of packing. Copyright © 2008 John Wiley & Sons, Ltd.

Various concentrations of heparin were employed in this study to immobilize on the acrylic acid-grafted and collagen/chitosan-immobilized polypropylene (PP-AAg-CCi) nonwoven fabric to improve the water absorbing and permeating properties. The immobilized heparin was verified by analyzing of the spectra of surface reflection infrared spectroscopy. It was found that the values of water absorbing and water diffusion coefficient for the PP-AAg-CCi sample immobilized with heparin (PP-AAg-CCHi) were significantly higher than those for the PP-AAg-CCi. The bacteria inhibition percentage and bacteria inhibition zone for the PP-AAg-CCHi were excellently. The pore and agent distribution for PP-AAg-CCi were examined with scanning electron microscope photographs. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

In this work, we successfully demonstrated a real-time mass sensor utilizing a MEMS-based self-sustained thermal-piezoresistive oscillator (TPO) fabricated by a standard silicon-on-insulator (SOI) MEMS process. From the measured data recorded by the frequency counter, not only a real-time frequency change with respect to the added mass can be detected but the dynamic impact and solvent evaporation process of the droplets was also successfully observed. The proposed MEMS TPO mass sensor has several key features, including real time monitoring, fast response time, high mass sensitivity of 3.4 Hz/pg, and most importantly very high mass resolution of only 100 fg estimated from the TPO's Allan deviation. Therefore, the proposed technology is expected to benefit both the fundamental science (high-resolution mass sensors for physical, chemical, and bio fields) and the industrial applications (such as PM2.5 sensors).

Defect concentrations in SiCOH low-k dielectrics deposited on high-resistivity silicon substrates were measured with Electron Spin Resonance (ESR). CP4 and HF treatmentswere used in order to eliminate dangling bonds from the backside of the silicon substrate as well as the sample edges. Two kinds of defects with characteristic g = 2.0054–2.0050 and g=2.0018–2.0020were detected in pristine samples and quantified using Lorentzian fitting. The defect with the g factor of 2.0054–2.0050 is likely to be fromthe silicon-dangling bonds. The defect with the g factor of 2.0018–2.0020 is most likely from carbon-related centers. Upon exposure to VUV synchrotron radiation (hν = 12 eV), the concentration of the silicon-dangling bonds is found to increase significantly. ispartof: Thin Solid Films vol:616 pages:23-26 status: published

This paper describes a scheme utilizing a set of low-cost and compact Kirkpatrick–Baez mirrors for upgrading the optical system of the Taiwan Inelastic X-ray Scattering beamline at SPring-8 for high-pressure experiments using diamond-anvil cells. The scheme as implemented improves the focus to 13 µm × 16 µm with transmission of up to 72%., Inelastic X-ray scattering (IXS) is a powerful technique capable of probing the dynamic behavior and electronic structure of materials. For IXS experiments under high pressure up to the megabar range using state-of-the-art diamond-anvil-cell technology, the sample volume is limited to the order of 1 × 10−3 mm3 for which a beam focus of the same order and less is often required. In this paper a scheme utilizing a set of low-cost and compact Kirkpatrick–Baez mirrors for upgrading the existing optical system of the Taiwan IXS beamline at SPring-8 is described. The scheme as implemented improves the focus to 13 µm × 16 µm (horizontal × vertical) with a transmission of up to 72% and a flux density gain of over 30 times, which has enhanced substantially the efficiency of the beamline for high-pressure research.

Cotton fabrics were crosslinked with dimethyloldihydroxyethyleneurea (DMDHEU) alone and DMDHEU/alpha-amino acids. The results showed that the values of nitrogen content, dry crease recovery angle and wet crease recovery angle of the crosslinked fabrics were ranked as DMDHEU > DMDHEU/aspartic acid > DMDHEU/glycine > DMDHEU/arginine under the same concentration of crosslinking agent. The reaction rate constant was also in the rank of DMDHEU > DMDHEU/aspartic acid > DMDHEU/glycine > DMDHEU/arginine. This rank agreed with the number of amine groups on the alpha-amino acids. From the data of free energies of activation, we found that the alpha-amino acids could affect the crosslinking reaction. The transition state complex for DMDHEU alone was significantly different from those for DMDHEU/ alpha-amino acids. From infrared spectra, the interaction between alpha-amino acids and aluminum ion was confirmed. The mechanisms of the interaction between alpha-amino acids and aluminum ion and the condensation reaction mechanisms between DMDHEU and alpha-amino acids are suggested in this study. The higher the number of carboxylic acid groups contained in the alpha-amino acids, the higher the crease recovery angle and reaction rate constant.

Three low-molecular-weight polyurethanes (LMWPU) containing various amounts of carboxylic acid were synthesized and applied on the nonwoven fabric for the improvement of water remaining property. The chemical structure of the LMWPUs was confirmed with 1H-NMR and 13C-NMR. The molecular weights of those three LMWPUs ranged from 3100 to 4200 g/mol. The results showed that the add-on values were increased with the increasing of the content of 2,2-bis(hydroxymethyl)propionic acid in LMWPU at a same resin concentration in padding bath. However, the water remaining values were decreased with the increasing of the content of 2,2-bis(hydroxymethyl)propionic acid in LMWPU for a given add-on value. The thermal properties, such as thermo-degradation and the values of Tg and Tm of the polymers, could not affect the water remaining property of the treated fabrics. The analyses of X-ray diffraction patterns and polarizing microscope observations showed that LMWPU with higher content of polytetramethyleneglycol had higher amorphous region. This phenomenon clearly supported that the values of water remaining were strongly affected by the amorphous region of the LMWPU polymers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

A degenerate mode 130-kHz ring-coupled gyroscope with auxiliary transducer array is designed to enhance the sensitivity as well as the mode-matching feature. The proof-of-concept device with 3 µm transducer's gap is fabricated using a conventional (100) silicon-on-insulator (SOI) wafer process with only two lithography steps. The auxiliary parallel-plate transducer array is located at the maximum displacement of the vibrating ring to enhance the electromechanical coupling while reducing the sensing noise. The in-plane trefoil mode (n=3) is adopted to alleviate the initial frequency splitting in (100) crystalline silicon device layer. The average frequency split for the drive/sense modes over multiple tested devices is only 225 ppm with the mean resonance frequency of 130 kHz. The measured Q-factor is 50 in atmospheric pressure and up to 10,000 in vacuum. Owing to the larger transduction area benefitting from the transducer array design, a low dc-bias voltage (V P ) of 3 V in vacuum (21 V in air) is sufficient to sustain the driving loop oscillation. As integrated with the sensing circuits to operate the proposed gyroscope, a scale factor of 2.2 mV/°/s and resolution of 0.26 °/s, respectively, are characterized in atmospheric pressure.

In this work, we report a thermally driven and piezoresistively sensed (a.k.a. thermal-piezoresistive) CMOS-MEMS resonator with high quality factor in ambient pressure and with decent power handling capability. The combination of (i) no need of tiny capacitive transducer's gap spacing thanks to thermal-piezoresistive transduction, (ii) the use of high-Q SiO 2 /polysilicon structural materials from CMOS back-end-of-line (BEOL), and (iii) the bulk-mode resonator design leads to resonator Q more than 2,000 in ambient pressure and 10,000 in vacuum. Key to attaining sheer Q in ambient pressure relies on significant attenuation of the air damping effect through thermal-piezoresistive transduction as compared to conventional capacitive resonators which necessitate tiny transducer's gap for reasonable electromechanical coupling. With such high Q and inherent circuit integration capability, the proposed CMOS-MEMS thermal-piezoresistive resonators can potentially be implemented as high sensitivity mass/gas sensors based on resonant transducers. The resonators with center frequency around 5.1 MHz were fabricated using a standard 0.35 µm 2-poly-4-metal (2P4M) CMOS process, thus featuring low cost, batch production, fast turnaround time, easy prototyping, and MEMS/IC integration.

The nanometer titanium dioxide (TiO2), succinic acid (SUA), and the mixture of nano- TiO2 and SUA were dispersed or dissolved in pure water, then irradiated with UV at the wavelength of 254 nm under stirring for different time periods respectively. The pH and conductivity values and UV-vis spectra of those solutions were recorded immediately. The powders obtained from the filtrated and vacuum dried from those solutions were examined with Fourier Transform Infrared Spectroscopy and Wide Angle X-Ray Diffraction meter. It shows that the crystalline structure and IR and UV-vis spectra of SUA adsorbed on nano-TiO2 particles are changed. The photo-reduced succinic acid in the presence of nanometer titanium dioxide under UV irradiation can create aldehyde group on SUA and free radical of SUA to improve the catalytic effects of crosslinking reaction between SUA and cotton cellulose.

The steeped procedure was used to investigate the physical properties and crosslinking structure. It was found that the values of the N content, dry crease recovery angle (DCRA), and wet crease recovery angle (WCRA) of the treated fabrics with any specific steeped procedure were higher than those of normally treated fabrics. For a given number of crosslinks per anhydroglucose unit (CL/AGU) the crosslinking length (CL length) values for the steep-pad-dry-cure process were higher than those for pad-dry-cure process. All the DCRA and WCRA values for the steep-pad-dry-cure process were higher than those for pad-dry-cure process at a given resin concentration, tensile strength retention (TSR), and CL/AGU. The surface distribution of crosslinking agent on the finished fabrics for pad-dry-cure process was higher than that for the steep-paddry-cure process. The expansion degree of the steep-pad-dry-cure treated fiber is slightly higher than that of the pad-dry-cure process. Those results obtained from pictures of SEM, crosslinking structure, and surface distribution of fibers/fabrics treated by the two processes clearly show that the crosslinking agents could diffuse and self-condensate in the treated fabrics to obtain an inner and longer crosslink under the steeped procedure so as to have good DCRA and WCRA.