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Two kinds of alpha-amino acids were used to combine with dimethylol-dihydroxyethyleneurea (DMDHEU) as crosslinking agents. It was found that the values of equilibrium dye absorption, dyeing rate constant and the structural diffusion resistance constant for various combinations of crosslinking agents were in the rank of DMDHEU-glutamic acid > DMDHEU-aspartic acid > DMDHEU alone at the same dyeing temperature. The activation energies of dyeing for the three crosslinked fabrics were ranked as follows: DMDHEU > DMDHEU-aspartic acid > DMDHEU-glutamic acid. The patterns of fiber cross-section obtained by scanning electron microscopy showed that the degree of the swelling of the DMDHEU crosslinked fiber was somewhat lower than that of DMDHEU-alpha-amino acid crosslinked fibers. From this it was concluded that the fabrics crosslinked with the DMDHEU-alpha-amino acid combinations had a larger pore structure.

Dimethyloldihydroxyethyleneurea and acrylic acid crosslinking agent was used to treat the cotton fabric with a pad-dry-plasma-cure process. Rate constants and structural diffusion resistance constants for the pad-dry-plasma-cure treated fabrics were lower than those for pad-dry-cure fabrics treated at the same resin concentration, and the values of dye absorption and equilibrium absorption of the plasma-treated fabrics were also lower than those for non-plasma-treated fabrics. However, the activation energies for the pad-dry-plasma-cure process were higher than that for the pad-dry-cure process. The anti-bacterial ability of the pad-dry-plasma-cure and pad-dry-plasma-cure with copper after-treatment fabrics were higher than that of pad-dry-cure and pad-dry-cure with copper after-treatment fabrics. The surface distribution of crosslinking agent for pad-dry-plasma-cure process was higher than for the pad-dry-cure process.

We used quasi-nanometer zirconium carbide (ZrC) and a polyurethane (PU) resin under roller pressure to form a composite film and found that the tensile strength at break, elongation at break, and modulus gradually decreased with increasing ultraviolet (UV)-irradiation time for films of both PU and the PU/ZrC composite. However, this phenomenon was significantly higher for the PU film than for the ZrC/PU composite film. The construction of the PU film changed after UV irradiation, but that of the PU/ZrC composite film was almost unchanged. The degradation of PU molecules occurred in the absence of ZrC particles after irradiation with UV light but almost did not occur in the presence of ZrC particles. This was confirmed with Fourier transform infrared spectroscopy and gel permeation chromatography analyses. It was suggested that polymer radicals which formed through the photooxidation of UV irradiation and free radicals which formed through the photoreduction of nanometer ZrC/UV irradiation interacted to form a dead polymer to stop the degradation; simultaneously, the chemical bonding between polymer molecules could be re-formed from free radicals created by photooxidation and photoreduction and thus reduce the mobility of PU molecules, thereby raising the glass-transition and melting temperatures of the soft segment. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4842–4849, 2006

Serine and glycine are selected as coreactants to combine with dimethylol-dihydroxyethyleneurea (DMDHEU). We found that the pore structures of DMDHEU-crosslinked cottons are changed. DMDHEU alone has lower values of equilibrium absorption, structural diffusion resistance constant, and rate constant, but higher value of activation energy than do DMDHEU–serine and DMDHEU–glycine. On the other hand, DMDHEU–serine has higher values of structural diffusion resistance constant and lower values of equilibrium absorption and rate constant than does DMDHEU–glycine; however, the hydroxyl group contained in serine has the higher affinity toward direct dye resulting in the decrease in the value of activation energy. The expansion patterns of cross section show that the degree of the expansion of the DMDHEU-crosslinked fiber is lower than that of the DMDHEU–serine- and DMDHEU–glycine-crosslinked fibers. The distribution of crosslinking agents on the crosslinked fabrics reveals the slightly higher surface distribution of DMDHEU–serine and DMDHEU–glycine. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1578–1584, 2006

Four different carboxylic acids (1,2,3,4-butane tetracarboxylic acid (BTCA), maleic acid (MA), succinic acid (SUA), and citric acid (CA)) were used as crosslinking agents for finished cotton fabrics in the presence of nanometer titanium dioxide catalyst under the irradiation of ultraviolet (UV) light and/or an electronic field (EF). We find that the dry crease recovery angle, wet crease recovery angle, and softness improvement percentages of the treated fabrics for all the crosslinking agents are gradually increased with the increasing of irradiation time period, but the TSR values decreased in all cases. The crease recovery and softness properties for the various crosslinking agents are ranked as BTCA > MA > CA > SUA at a given UV irradiation time period. The addition of EF treatment on the UV-irradiated fabrics improves the catalytic effects significantly. The spectra of Fourier transform infrared spectrophotometry reveal the crosslinking reaction between the carboxylic acid group of citric acid and the hydroxyl group of methylcellulose; this reaction could form ester and ether groups in the presence of nanometer TiO 2 catalyst under UV irradiation and UV irradiation and EF treatment. The pictures of scanning electron microscopy and the electron spectroscopy for chemical analysis survey spectra show the surface deposition of acid crosslinking agents on the finished fibers and the crosslinking reaction between citric acid and cellulose molecule catalyzed with nanometer titanium dioxide under the irradiation of UV only and under the irradiation of UV and the treatment of EF separately.

Investigations on white spirit and acetone permeation resistance of modified polyamide and nylon 6 clay (MPANYC) blends and their corresponding polyethylene/MPANYC bottles were reported in this study. The white spirit and acetone permeation resistance of MPANYC sheets improve consistently with increasing NYC contents present in MPANYC resins after blending nylon 6 clay (NYC) in modified polyamide (MPA) resins. However, the order of barrier improvement of the PE/MPANYC and PE/NYC bottle specimens is not corresponding to the order of barrier improvement of the MPANYC and/or NYC barrier resins added in PE. The blow-molded PE/NYC bottle specimen exhibits similarly worse white spirit and acetone solvent permeation resistance as the PE bottle specimen, wherein no clearly formed NYC laminas but only dispersed NYC droplets or agglomerates were found on the fracture surfaces of the PE/NYC bottles. However, after blending optimum compositions of MPANYC in PE, the PE/MPANYC bottles with demarcated MPANYC laminas exhibit significantly better white spirit and acetone permeation resistance than the PE/MPA bottle, wherein the white spirit and acetone permeation rates of the PE/MPA8NYC1 bottle are about 1.3 and 1.4 times slower than those of the PE/MPA bottle, respectively. In order to understand these interesting barrier properties of PE/MPANYC and PE/NYC bottles, rheological, thermal, wide angle X-ray diffraction and morphological properties of the base MPANYC and NYC resins and their corresponding morphology present in the blow-molded bottles were investigated.

The blending and barrier properties of the MPAEVOH blends of modified polyamide (MPA) and ethylene vinyl alcohol copolymer (EVOH) were systematically in- vestigated in this study. After blending MPA in EVOH resin, a noticeable "negative deviation" was found on the plot of the oxygen permeation rate versus MPA content when the MPA contents present in MPAEVOH resins reach about 80 wt %. The peak tempera- tures associated with the main melting endotherm of MPA and EVOH reduce significantly with increasing the EVOH and MPA contents present in MPAEVOH resins, respectively. The melting endotherm and X-ray diffraction peak associated with EVOH crystal phases disappear gradually as the MPA contents present in MPAEVOH increase. In fact, the melting endotherm and X-ray scattering peak corresponding to EVOH crystals almost disappear as the EVOH contents present in MPAEVOH specimens are less than 20 wt %. Further Fourier-Transform Infrared (FT-IR) investigations indicate that the strengths of intermolecular hydrogen bonds of MPAEVOH specimens reduce significantly as the MPA contents increase, wherein the self-associated hydroxyl-hydroxyl bonds within EVOH resins almost disappear as the EVOH contents reduce to be less than about 20 wt %. As expected, the average sizes of the free volume holes of MPAEVOH specimens increase significantly as the MPA contents increase. However, somewhat surprisingly, a clear negative deviation was found on the plot of the numbers and fractional free volumes of free volume holes against the MPA contents as the EVOH contents are close to about 20 wt %. The interesting barrier properties of the MPA, EVOH, and MPAEVOH specimens were investigated in terms of the free volume and intermolecular interaction properties in the amorphous phases of MPAEVOH specimens described above. © 2005 Wiley Periodicals, Inc. J

Four different carboxylic acids, 1,2,3,4-butane tetracarboxylic acid (BTCA), maleic acid (MA), succinic acid (SUA), and citric acid (CA), were used as crosslinking agents to treat cotton fabrics in the presence of nanometer titanium dioxide (TiO2) as a catalyst under UV irradiation. The dry crease recovery angle (DCRA) and wet crease recovery angle (WCRA) values of the treated fabrics were ranked BTCA > MA > CA > SUA and the tensile strength retention (TSR) values were ranked BTCA CA ≒ SUA; and at a given value of the TSR, the WCRA and DCRA values were both ranked in the order BTCA > MA > CA > SUA. The softness values of the carboxylic acid treated fabrics in the presence of nanometer TiO2 catalyst were all better than that of the untreated fabric. Surface deposition of the treated fabrics for BTCA, which contains one vinyl double bond and four carboxylic acid groups, was higher than that for CA, which contains no vinyl double bond. IR spectra and electron spectroscopy for chemical analysis survey spectra showed the ester bond crosslink between the cellulose molecule and the various acids used in this study. The values of DCRA, WCRA, and add-on of the CA crosslinked fabrics for the mixed catalysts were in the order ZrO2/TiO2 < SiO2/TiO2 < Ag/TiO2. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2450–2456, 2005

Serine and glycine were used to combine with dimethyloldihydroxyethyleneurea (DMDHEU) as crosslinking agents to study the physical properties of the crosslinked fabrics and the reaction kinetics, and find that the bound nitrogen is in the series of DMDHEU >> DMDHEU-serine > DMDHEU-glycine at the same resin concentration. The results also show that the wet crease recovery angle (WCRA) value of the treated fabrics for the three crosslinking agent systems is in the series of DMDHEU-serine > DMDHEU-glycine > DMDHEU alone at a given dry crease recovery angle (DCRA). The DCRA values of the treated fabrics for DMDHEU alone are higher than those for DMDHEU-α-amino acids for a given value of tensile strength retention (TSR). WCRA values for the various treated fabrics is in the rank of DMDHEU-serine > DMDHEU alone > DMDHEU-glycine at the same TSR. Rate constants for the various crosslinking agents are in the series of DMDHEU-glycine > DMDHEU-serine > DMDHEU alone at the given heated temperatures. Energies needed to crosslink and the values of enthalpies and entropies of activation are all DMDHEU-glycine > DMDHEU-serine > DMDHEU alone. Infrared ray (IR) spectra strongly suggest the reaction between DMDHEU and serine and the reaction between the hydroxyl group (cellulose) and serine can occur in the pad-dry-cure process, but only a little for the latter. The reaction between the functional groups of serine and the aluminum ion to form a complex also confirm with IR spectrum.

Two dicarboxylic acids (maleic acid and tartaric acid) were used in conjunction with DMDHEU as the crosslinking agents to treat cotton fabric samples. The treated fabrics then were dyed with direct red 81. The results show that the values of the dye absorption, equilibrium absorption, rate constants, and the pore index of structural diffusion resistance constant for the various crosslinking agents are ranked as DMDHEU-tartaric acid > DMDHEU-maleic acid > DMDHEU alone at the same dyeing temperature. The activation energies for the three crosslinked fabrics are in the rank of DMDHEU > DMDHEU-maleic acid > DMDHEU-tartaric acid. The CL length values for the various crosslinking agent systems are in the series of DMDHEU-tartaric acid > DMDHEU-maleic acid > DMDHEU alone for a given number of CL/AGU. The values of the pore index of structural diffusion resistance constant and dyeing rate constant are increased with the increase of CL length. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 143–148, 2005

Three metallic salts were used to posttreat dimethyloldihydroxyethyleneurea (DMDHEU)/aerylic acid (AA) crosslinked cotton fabrics, and the results showed that at a given value of the tensile strength retention (TSR), the dry crease recovery angle (DCRA) and wet crease recovery angle (WCRA) of the crosslinked and posttreated fabrics were higher than those of the DMDHEU-AA-treated fabrics, and those of the crosslinked and posttreated fabrics were in the order of Ag + > Cu +2 > Al +3 . The DCRA and TSR values for the crosslinked and posttreated fabrics were higher than those for the DMDHEU-AA-crosslinked fabrics, and those for the crosslinked and posttreated fabrics were in the order of Ag + > Cu +2 > Al +3 ; however, WCRA values for the crosslinked and posttreated fabrics were lower than those for the DMDHEU-AA-crosslinked fabrics, and those for the crosslinked and posttreated fabrics were ranked as Ag + > Cu +2 > Al +3 at a given number of crosslinks per anhydroglucose unit. IR spectra clearly revealed the different interactions and bonding states between the hydroxyl group of the cellulose and the various metallic ions and the strength of the interaction. All crosslinked and posttreated fabric samples showed good odor absorption and antibacterial and washing-fastness properties.

A steeped procedure was introduced to the durable press finishing process in this study to study some physical properties, the crosslinking structure, and the pore structure. The results showed that the values of the dry and wet crease recovery angles of fabrics treated with the steep–pad–dry–cure process were higher than those of fabrics treated with the pad–dry–cure process, and those phenomena increased with higher steeped temperatures and longer times. The lengths of the crosslinks for the steep–pad–dry–cure process were higher than those for the pad–dry–cure process at a given number of crosslinks per anhydroglucose unit. The fabrics treated with the steep–pad–dry–cure process had higher values of the dye absorption, rate constant, and structural diffusion resistance constant than those treated with the pad–dry–cure process at the same dyeing temperature; however, they had lower values of the equilibrium absorption and activation energy than those treated with the pad–dry–cure process. The results of thin-layer chromatography, H-NMR, 13C-NMR, and IR analyses suggested that self-condensation between the crosslinking agents occurred during the steeped procedure. Additionally, the steep–pad–dry–cure-treated fabric had more inner agent distribution than the pad–dry–cure-treated fabric. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2555–2562, 2005

The various weight ratios of collagen/chitosan were used to immobilize the various grafted amounts of acrylic acid (AA) grafted polypropylene nonwoven fabric. For a given value of grafting percentage of AA and the immobilizing time period, the values of the immobilizing percentage of collagen/chitosan are increased with the increasing of chitosan contained in the mixtures of collagen/chitosan. The antibacterial properties are also increased with the increasing of chitosan in the mixtures of collagen/chitosan and the immobilizing percentage of collagen/chitosan. The crosslinking reaction between the AA-grafted PP nonwoven fabrics and collagen/chitosan with glutaraldehyde are clearly sustained by examination from the spectra of the surface reflection infrared spectroscopy (IR). The values of water uptake and water diffusion coefficients are decreased with the increasing of chitosan in the mixtures of collagen/chitosan and the immobilizing percentages of collagen/chitosan at the same pH value of buffering water. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 391–400, 2005

Two kinds of alpha-amino acids are used to combine with dimethylol-dihydroxyethyleneurea (DMDHEU) as crosslinking agents, and the specific rate constants and other activation parameters are discussed. From the results, we find that the rate constants for the various crosslinking agent systems are in the order of DMDHEU > DMDHEU-aspartic acid > DMDHEU-glutamic acid. The energies needed to crosslink are in the rank of DMDHEU-glutamic acid > DMDHEU-aspartic acid > DMDHEU. The values of enthalpy and entropy for DMDHEU are lower than those for DMDHEU-alpha-amino acids, and enthalpy values for DMDHEU are significantly lower than those for DMDHEU-alpha-amino acids. The data of various activation parameters reveal that the reaction state of DMDHEU-alpha-amino acids is different from that of DMDHEU. Additionally, the reactions between aluminum sulfate and aspartic acid are confirmed by infrared spectra.

We have used three different processes to treat cotton fabrics with different combined weight ratios of dimethylolethyleneurea (DMEU) and dimethylol-N,N'-dimethylene-tris ethyleneurea (DMDME3EU) as crosslinking agents, and have found that a two-step process of pad(DMDME3EU)-dry-cure-pad(DMEU)-dry-cure yields higher dry crease recovery angles (DCRA), wet crease recovery angles (WCRA), and equilibrium direct dye adsorption values than the other two processes of pad(DMEU)-dry-cure-pad(DMDME3EU)-dry-cure and pad- (mixture of DMEU and DMDME3EU)-dry-cure at the same nitrogen content and a combined ratio of equal concentrations of the two agents. The process of pad(DMDME3EU)-dry-cure- pad(DMEU)-dry-cure also yields higher DCRA values for a given wet crease recovery angle and tensile strength retention and an even crosslinking agent distribution in/on the treated fabrics. At the same time, the DCRA and WCRA values for the pad(DMDME3EU)-dry-cure- pad(DMEU)-dry-cure process are higher than those for the other two processes at a given number of crosslinks per anhydroglucose unit.

Two dicarboxylic acids were used to join with dimethyloldihydroxyethyleneurea (DMDHEU) as crosslinking agents to treated cotton fabrics. These results reveal that the dry crease recovery angle values of the treated fabrics for DMDHEU-maleic acid are higher than those for DMDHEU-tartaric acid at a given wet crease recovery angle and tensile strength retention. The IR spectra show that the reaction between the -OH of DMDHEU and cellulose and the vinyl groups of maleic acids occurred. The cross section of the DMDHEU-maleic acid and DMDHEU-tartaric acid treated fibers and the energies of activation and other data of reaction kinetics for DMDHEU-maleic acid and DMDHEU-tartaric acid strongly suggest that the reaction of vinyl groups of maleic acid with cellulose molecules can take place during the pad/dry-cure process. Additionally, the surface distribution of crosslinking agent on the finished fabrics for DMDHEU-maleic acid is slightly lower than that for DMDHEU-tartaric acid.

The oxygen permeation resistance of polyethylene (PE), polyethylene/ethylene vinyl alcohol copolymer (PE/EVOH), polyethylene/modified ethylene vinyl alcohol copolymer (PE/MEVOH), and polyethylene/modified polyamide–ethylene vinyl alcohol copolymer (PE/MPAEVOH) bottles was investigated. The oxygen permeation resistance improved significantly after the blending of ethylene vinyl alcohol copolymer (EVOH) barrier resins in PE matrices during blow molding; less demarcated EVOH laminas were found on the fracture surfaces of the PE/EVOH bottles. Surprisingly, the oxygen permeation resistance of the PE/MEVOH bottles decreased significantly, although more clearly defined modified ethylene vinyl alcohol copolymer (MEVOH) laminas were found for the PE/MEVOH bottles as the compatibilizer precursor contents present in the MEVOH resins increased. In contrast, after the blending of modified polyamide (MPA) in EVOH resins, more demarcated modified polyamide–ethylene vinyl alcohol copolymer (MPAEVOH) laminar structures were observed in the PE/MPAEVOH bottles as the MPA contents present in the MPAEVOH resins increased. In fact, with proper MPAEVOH compositions, the oxygen permeation resistance of the PE/MPAEVOH bottles was even better than that of the PE/EVOH bottles. These interesting oxygen barrier and morphological properties of the PE, PE/EVOH, PE/MEVOH, and PE/MPAEVOH bottles were investigated in terms of the free volumes, barrier properties, and molecular interactions in the amorphous-phase structures of the barrier resins present in their corresponding bottles. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2528–2537, 2004

We used three kinds of alkyl diallyl ammonium salts (methyl, ethyl, and propyl) in combination with dimethyloldihydroxyethyleneurea (DMDHEU) as crosslinking agents. The nitrogen content, dry crease recovery angle (DCRA), moisture regain, and wicking height for the DMDHEU/alkyl diallyl ammonium salts were in the order of CH3 > C2H5 > C3H7, but the wet crease recovery angle (WCRA) and tensile strength retention (TSR) were in the opposite order at the same resin concentration. For the same DCRA and TSR, the WCRA values for only DMDHEU were lower than those for DMDHEU/alkyl diallyl ammonium salts, and the WCRA values for DMDHEU/alkyl diallyl ammonium salts were in the order of C3H7 > C2H5 > CH3. Both the OH group of the cellulose and DMDHEU could react with the vinyl or epoxy groups of the alkyl diallyl ammonium salts during the pad–dry–cure process. The surface migration for DMDHEU/alkyl diallyl ammonium salts was in the order of CH3 > C2H5 > C3H7. Fabrics treated with DMDHEU/alkyl diallyl ammonium salts showed good antibacterial properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1662–1669, 2003

We have used alpha-amino acids (aspartic acid and glutamic acid) to join with dimethyloldihydroxyethyleneurea (DMDHEU) as crosslinking agents, and have found that at a given resin concentration, the wet crease recovery angle (WCRA) and tensile strength retention (TSR) values of the treated fabrics are in the order of DMDHEU- glutamic acid > DMDHEU-aspartic acid > DMDHEU; however, the dry crease recovery angle (DCRA) values are in the inverse rank. Nitrogen content and wicking height (wH) values for the various finished fabrics rank as DMDHEU-aspartic acid > DMDHEU- glutamic acid > DMDHEU. We have also found that the WCRA and DCRA of DMDHEU- alone treated fabrics are lower than those of the DMDHEU-alpha-amino-acid treated fabrics, and are ranked as DMDHEU-glutamic acid > DMDHEU-aspartic acid > DMDHEL' alone at a given TSR. The reaction between the —OH of DMDHEU and the amino and acid groups of alpha-amino acids in a pad-dry-cure process are confirmed by IR spectra. Surface distribution of the crosslinking agent on the finished fabrics is similar for DMDHEU alone and DMDHEU-alpha-amino acid.

In this study, we pretreat aramid (Nomex®) yarns with ethylene diamine (EDA), diethylene triamine (DETA), and triethylene tetramine (TETA) under different conditions and study some physical properties. The values of changes in tensile strength retention ΔTSR increase and then decrease, and basic dye uptake [D] f and wicking height WH increase with increased pretreating temperature, time period, and amine concentration. The rank of the minus values of Δ TSR for the pretreated fibers is EDA > DETA > TETA. but the tendencies of the plus values of ΔTSR and of [ D] f, WH, and shrinkage are inverse at a given pretreating temperature, time period, and amine concentration. The glass transition temperatures and densities of the crystals are ranked as EDA > DETA > TETA. Surface etching on TETA pretreated fibers is more obvious than on EDA pretreated fibers. The polymer chains of aramid fibers may rearrange through shrinkage of the fibers during pretreatment, and some degradation of the Nomex polymer chains may occur at higher amine concentrations.

This work reports wing-type thermal-piezoresistive oscillators operating at around 840 kHz in vacuum with ultra-low power consumption of only 70 µW for the first time. The combination of N-type heavily doped silicon with negative piezoresistive coefficients and sub-micron cross-sectional dimensions of the thermally actuated beams is key to ensuring self-sustained oscillation under sub-100µW level. In particular, shrinking thermal beam cross-sections in 2D is a novel and effective approach to achieve better figure of merit (e.g., FOM defined by the ratio of transconductance g m to dc power consumption P DC ) of the self-sustained oscillators. By using proper control of silicon etching (ICP) recipe, the sub-micron cross-sectional dimensions of the thermally actuated beams can be easily and reproducibly fabricated in one process step. The phase noise of the proposed wing-type oscillators is also investigated in this work with −93.41 dBc/Hz at 1-kHz offset and −97.95 dBc/Hz at 100-kHz offset in air, and −95.9 dBc/Hz at 1-kHz offset and −95.7 dBc/Hz at 100-kHz offset in vacuum, respectively.

In this study, we use dimethyloldihydroxyethyleneurea to treat cotton fabrics with various processes by changing the bath concentrations. We find that dry and wet crease recovery angles of the fabrics treated with the pad-dry-high-pressure-steam (HPS) cure process are higher than those for other processes at a given tensile strength retention. Crosslinking length and dry and wet crease recovery angles of the fabrics finished with the pad-dry-HPS-cure process are higher than those for the pad-dry-cure process for a given number of crosslinks per anhydroglucose unit. Additionally, the surface distribution of the crosslinking agent on the fabrics finished with the pad-dry-HPS-cure process is more significant than that for the pad-dry-cure process.

Cotton fabrics finished with pre-reacted dimethyldimethyloldihydroxylethyleneurea and acrylic acid (DMDMDHEU-AA) show that the wet crease recovery angle (WCRA), moisture regain (MR), and wicking height (WH) values of the treated fabrics increase with increasing pre-reaction temperature, time, hydrogen peroxide content, and AA content. The WCRA, MR, and WH values for the fabric samples finished with the pre-reacted DMDMDHEU-AA are higher than those with the DMDMDHEU for all cases, and the MR values are similar to those of the unfinished cotton fabric. For the same mole ratio of DMDMDHEU to AA, the finished fabric samples for the pre-reacted solutions have higher WCRA, MR, and WH values compared with those for unreacted solutions. Additionally, fabrics finished with the DMDMDHEU-AA pre-reacted in the presence of hydrogen peroxide/sodium sulfite, hydrogen peroxide/sodium thiosulfate, and hydrogen peroxide/thiourea in the pre-reaction solutions also have higher WCRA, MR, and WH values. Finished fabrics treated with pre-reacted DMDMDHEU-maleic acid have significantly higher dry and wet crease recovery angles than those treated with DMDMDHEU-AA.

Dimethyloldihydroxyethyleneurea (DMDHEU) and acrylic acid (AA) were used to synthesize the dimethyloldihydroxyethyleneurea–acrylic acid product (DMDHEU–AA, mole ratios of DMDHEU/AA = 1/0, 1/1, and 1/2, respectively). Cotton fabrics were treated with the various prereacted DMDHEU–AA products by changing resin concentrations in the bath. We found that the dry crease recovery angle (DCRA) and wet crease recovery angle (WCRA) of the treated fabrics increased with the increase of acrylic acid in the prereacted DMDHEU–AA at the same value of resin concentration in the bath, whereas the tensile strength retention (TSR) showed the inverse tendency. For a given value of number of crosslinks per anhydroglucose unit (CL/AGU), the DCRA and WCRA values of the DMDHEU–AA-treated fabrics were higher than those for DMDHEU-treated fabrics. Additionally, agent distribution and the reaction between –COOH of the crosslinking agent and cellulose molecule were also investigated in this study. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1580–1586, 2001

Sulfonated and unsulfonated cotton fabrics are finished with DMDMDHEU to study the agent distribution and reaction kinetics. The surface concentration of the crosslinking agent on the finished fabrics is significant for sulfonated cottons. Specific reaction rate constants for sulfonated cottons are higher than for the unsulfonated fabric, and the rate constant for the higher degree of sulfonation is greater than for the lower degree. Sulfonation does not affect the energy needed for the crosslinking reaction. Enthalpies of activation for sulfonated fabrics are lower than for the unsulfonated fabric, and the higher the degree of sulfonation, the lower the enthalpy of activation. Entropies of activation decrease with increased degree of sulfonation. Sulfonation of cotton does affect the reaction state, but does not affect energy consumption in the reaction between cellulose and the crosslinking agent.

Various degrees of sulfonated and unsulfonated cotton fabric samples are treated with DMDHEU in the presence of a mixed catalyst under mild curing temperatures. At a given DMDHEU concentration in the bath, the nitrogen contents of the finished fabrics increase with increasing degrees of sulfonation, while the formaldehyde content de creases. ΔWCRA values increase with increasing sulfonation at the same values of ΔDCRA and ΔTSR. For a given value of CL/AGU, the ΔWCRA and CL length values increase as the sulfonation degree of the fabrics increases.

Absorption time curves from finite baths are determined for untreated and cross-linked cotton fabrics dyed with Direct Red 81 under different conditions. A new method is described for kinetic analysis of absorption time curves. Structural coefficients, electrical coefficients, and dyeing rate constants are determined from the time curves. Crosslinking reduces the electrical coefficients, dyeing rate constants, and activation energy, but increases the structural coefficients (decreases the pore size). The structural coefficient is only affected by crosslinking in this study. The electrical coefficient and dyeing rate constant values are affected very little by dye concentration in aqueous solution in the cases of crosslinked and untreated cotton. However, both electrical coefficient and dyeing rate constant are affected by dyeing temperature and liquor ratio in the two cases.

A cutting-edge ovenized micromechanical resonator circuit comprised of a double-ended tuning fork (DETF) resonator and serpentine-shaped heaters to enable ultra-low heater power of only 0.47 mW over the entire temperature range (-40°C to 85°C) has been reported for the first time in a low-cost, foundry CMOS-based fabrication platform. The combination of low thermal conductivity materials (i.e., SiO2 and poly-Si) and high thermal isolation designs is key to attaining low heater power consumption in a sub-mW level. An ovenized 1.2-MHz CMOS-MEMS oscillator with a phase noise lower than -103 dBc/Hz at 1-kHz offset and -110 dBc/Hz at 1-MHz offset was also demonstrated in this work, verifying the great potential of low power oven-controlled MEMS oscillators realized using the well-established CMOS-MEMS technology.

A crosslinking treatment is reported for cotton fabric with dimethyldimethyloldihy droxyethyleneurea ( DMDMDHEU ) in the presence of various amounts of sodium chlo ride using a pad-dry-cure process. The crosslinked fabric and a control are studied for various physicochemical properties using standard methods. The distribution of cross links per anhydroglucose unit and the length of crosslinks are calculated from form aldehyde and nitrogen contents. Both number and length of crosslinks decrease with increased NaCl concentration in the pad bath. Self-condensation of resin and surface distribution ( on the treated fabrics ) are evident for fabric samples treated in the presence of sodium chloride. The relationships between various treated fabric properties are also considered.

In this work, the effect of vacuum ultraviolet (VUV) photon irradiation on the time-dependent dielectric breakdown (TDDB) of low-k organosilicate thin films was investigated, with particular emphasis on extrinsic TDDB (includes Cu migration effects). State-of-the-art low-k a-SiOC:H thin films were utilized because of their relevance as both an interlayer dielectric and as a candidate Cu capping-layer material. Synchrotron radiation was used to mimic VUV photon irradiation from processing plasmas without the presence of charged particles. TDDB characteristic lifetimes of the low-k a-SiOC:H dielectrics, before and after VUV photon exposure, were measured based on a Ti/a-SiOC:H/Cu metal-insulator-metal structure. The deterioration of extrinsic TDDB was observed in the film after exposure to VUV photons with 9 eV energy. The most notable degradation of the dielectric characteristic lifetime was found when the Cu electrode was used as an anode in the sample after 9.0 eV VUV photon exposure (photon fluence is 4...

In this work, we proposed a methodology to enhance thermal stability of MEMS resonators by the use of a constant-structural-resistance control where temperature coefficient of resistivity (TCR) of the MEMS resonator serves as an instrinsic temperature sensor, thus leading to a constant structural temperature to greatly alleviate the frequency drifts due to change of ambient temperature. As a proof of concept, the effective temperature coefficient of frequency (TCf) was measured under a manual control of bias power with one-point calibration to maintain constant structural resistance, ultimately demonstrating up to 46 times improvement of temperature stability as compared to uncompensated counterparts. This technology prevents the use of external temperature sensors or reference resonators with which errors occur due to indirect temperature measurement of the active MEMS resonator. Notably, this technology is well suited for all kinds of MEMS resonators featuring proper temperature-dependent structural resistance, such as capacitive, piezoresistive, piezoelectric, and thermal-piezoresistive silicon-based resonators.

Cotton fabric is finished with dimethylodimethyldihydroxyethyleneurea using the pad-dry-cure process and different weight ratios of H2O/MeOH mixtures as solvents. Relationships between physical properties and weight ratios of H2O/MeOH show that WCRA and TSR values for the H2O/MeOH mixtures are higher than the theoretical values, but DCRA, nitrogen content, and formaldehyde content values for the H2O/ MeOH mixtures are lower than the theoretical values. WCRA values of the fabric samples treated using H20/MeOH = 40/60 mixtures are higher than those using the 100% water and methanol at the same DCRA and TSR values; in addition, WCRA values of the fabric samples treated using 100% methanol are higher than those using 100% water at the same DCRA and TSR values. The H2O/MeOH = 40/60 mixture gives higher WCRA values than the 100% methanol and water at the same CL/AGU, and the H 2O/MeOH = 0/100 gives higher WCRA values than the H2O/MeOH = 100/0 at the same CL/AGU. For a given CL/AGU, the TSR values of the treated fabric using the three different H2O/MeOH mixtures as solvents are ranked 0/100 > 40/60> 100 / 0, but DCRA values show an opposite trend. At the same CL /AGU, the CL lengths of the samples treated with mixtures of H2O/MeOH as solvents are ranked 0/100 > 40/60 > 100/0.

A very-high-frequency (VHF) bulk-mode II-BAR CMOS-MEMS resonator array with electrothermal actuation and piezoresistive sensing (thermal-piezoresistive transduction) under a novel differential mode of operation has been demonstrated for the first time using a standard 0.35μm CMOS process. The proposed array consists of SiO 2 and embedded polysilicon, the former of which provides high-Q structural material while the latter serves as both joule-heating elements and piezoresistors. Such a thermal-piezoresistive II-BAR array technique not only inherits all advantages from the single II-BAR but also shows great potential for low feedthrough, low motional impedance, and high power efficiency in VHF or ultra-high-frequency (UHF) operation using advanced down scaling and large-scale integrated (LSI) arrays.

A novel balanced two-port measurement technique capable of adjusting feedthrough signal has been proposed to demonstrate both cancellation and tuning of feedthrough levels for one-port thermally actuated resonator with piezoresistive sensing (thermal-piezoresistive resonator), therefore attaining clean frequency spectra and real resonance characterization. Conventional one-port thermal-piezoresistive resonators significantly suffer high transmission feedthrough and often necessitate post-data processing and de-embedding to extract pure resonance behavior. For the first time, the one-port thermal-piezoresistive resonators with longitudinally vibrating mode shape were tested using the proposed technique to offer the directly measurable resonator Q, motional impedance, and resonance frequency with an improvement of around 80 dB feedthrough reduction. This approach could be easily applied to any one-port thermal-piezoresistive resonator with much higher frequency, showing great potential to enable future sensor and RF applications.

A crosslinking treatment with dimethyldimethyloldihydroxyethyleneurea (DM- DMDHEU) is reported for cotton fabrics premercerized with different alkalis at normal (constant) length (warp and weft). The number of crosslinks per anhydroglucose unit (CL/AGU) and crosslink lengths (CL) are calculated from formaldehyde and nitrogen contents. Data on formaldehyde and nitrogen contents, physical properties, and num ber and length of crosslinks are discussed. The value of CL length for unmercerized cotton is higher than that for mercerized fabrics at the same pad bath resin concen tration, but CL/AGU for the former is lower than the latter. ΔDCRA and Δ W CRA values of the various premercerized cottons are ranked LiOH mercerized > NaOH mercerized > KOH mercerized > unmercerized fabric; however, the ranking of ΔTSR and ΔER values is in the order of unmercerized > KOH mercerized > NaOH mer cerized > LiOH mercerized fabric at the same nitrogen content and CL/AGU. The swelling of the various mercerized and crosslinked fabrics is ranked LiOH mercerized > NaOH mercerized > KOH mercerized > unmercerized fabric.

We present an in vivo test platform to evaluate the antioxidative capability of seven frequently used dermocosmetic antioxidants on the human stratum corneum (SC). It has been reported that the protein carbonylation could be used as a biomarker for oxidative stress. The current study detects the change of the level of exposed protein carbonyl group in the most outer layer of human SC. The concentration of the antioxidant in each subject emulsion formulation was 0.5% (w/w). The data indicated that alpha-tocopherol (α-Vit E) and ascorbic acid (Vit C) have excellent antioxidative capability and α-Vit E-acetate possesses better than the average antioxidative capability. The bioconversion of α-Vit E-acetate to α-Vit E may occur in the human SC during a less than 2 weeks time course test. Lipoic acid possessed moderate antioxidative capability. Ascorbyl 6-palmitate had a low antioxidative capability. Ascorbic acid 2-glucoside represented an insignificant antioxidative capability. Glutathion (GSH) had no effect on reducing oxidative damage to human SC proteins, implying that the GSH recycling system could be absent in human SC. This test platform is an useful tool to evaluate the antioxidative efficiency of antioxidants on human SC proteins.

This paper reports an improved method for neglecting the distance effect in extracellular neuron recording and objective comparison of biological and electro-chemical properties between gold (Au) and multi-walled carbon nanotubes (MWCNTs) based microelectrode arrays (MEA). The response amplitude of action potential using MWCNTs that marked by a signal-to-noise ratio (SNR) as high as 50.06± 1.47 dB. Whether the MEA located in different positions, the average SNR is more than 1.5-fold for the MWCNTs compared to the Au electrode.

We designed, fabricated and tested a novel prototype neural interface using two-dimensional single-atom-thick graphene as microelectrode for neural applications. The cytotoxicity indicated a satisfactory biocompatibility and non-toxicity. The treatment graphene with steam plasma improved the biological properties. The action potentials of lateral giant (LG) nerve fiber of the escape circuit of an American crayfish had a ratio of signal to noise (SNR) as great as 30.2±2.45 dB.

We studied the properties of cotton fabric samples premercerized with three kinds of alkalis and crosslinked with varying DMDHEU concentrations in the finishing bath. At a given nitrogen content and number of crosslinks, the change in wet crease recovery angle of finished fabrics from various premercerizing solutions ranked in the order of LiOH mercerized fabric > NaOH mercerized fabric > KOH mercerized fabric > unmercerized fabric. However, changes in tensile strength and elongation of the finished fabrics for the various premercerized samples are ranked as KOH mer cerized fabric > NaOH mercerized fabric > LiOH mercerized fabric > unmercerized fabric for a given nitrogen content and number of crosslinks. The value of crosslink length for the various finished fabrics has the same order at a given number of crosslinks. Degrees of surface migration of the agent on the finished fabric surface with NaOH and KOH premercerizing are significant.

We have studied the dyeing kinetics of mercerized and mercerized and crosslinked cotton fabrics slack-mercerized with different alkalis. Regardless of whether or not the fabrics were treated with the crosslinking agent, the activation energies and the values of equilibrium adsorption for the various fabrics are ranked as follows: unmercenzed fabric > KOH mercerized fabric > NaOH mercerized fabric > LiOH mercerized fabric. However, the order of the rate constants and the structural diffusion resistance constants for the various cottons is LiOH mercerized fabric > NaOH mercerized fabric > KOH mercerized fabric > unmercerized fabric.

A crosslinking treatment with dimethyldimethyloldihydroxyethyleneurea (DM- DMDHEU) is reported for cotton fabrics premercerized with different alkalis at normal (constant) length (warp and weft). The number of crosslinks per anhydroglucose unit (CL/AGU) and crosslink lengths (CL) are calculated from formaldehyde and nitrogen contents. Data on formaldehyde and nitrogen contents, physical properties, and num ber and length of crosslinks are discussed. The value of CL length for unmercerized cotton is higher than that for mercerized fabrics at the same pad bath resin concen tration, but CL/AGU for the former is lower than the latter. ΔDCRA and Δ W CRA values of the various premercerized cottons are ranked LiOH mercerized > NaOH mercerized > KOH mercerized > unmercerized fabric; however, the ranking of ΔTSR and ΔER values is in the order of unmercerized > KOH mercerized > NaOH mer cerized > LiOH mercerized fabric at the same nitrogen content and CL/AGU. The swelling of the various mercerized and crosslinked f...

Adsorption time curves from finite baths have been studied for untreated cotton fabric and cottons treated with differing molecular chain lengths of aldehydes (formaldehyde and glutaraldehyde). Crosslinking reduced the rate constant, structural diffusion resistance constant, and equilibrium adsorption of dyeing. Additionally, these data decreased with increasing agent concentration and with increasing molecular chain length of the crosslinking agent. The dyeing activation energy of the glutaraldehyde treated fabric was lower than that of the formaldehyde treated fabric.

Cotton fabric has been crosslinked with differing molecular chain lengths of an aldehyde crosslinking agent (formaldehyde and glutaraldehyde). The formaldehyde treated fabric shows lower tensile strength retention than the glutaraldehyde treated fabric but higher elongation retention for a given agent concentration. At the same dry or wet crease recovery angle, tensile strength of the formaldehyde treated fabric is lower than that of the glutaraldehyde treated fabric, but elongation is higher. Wet crease recovery of the formaldehyde treated fabric is better than that of the glutaraldehyde treated fabric. The degree of surface migration is similar for both fabrics. Agent distribution in the treated fibers is different for the differing molecular chain lengths of the crosslinking agents.

This paper reports an improved method for reducing the impedance of microelectrode array (MEA). The impedance reduction is generally required by increasing the effective surface area of electrode. We have fabricated and treated the multi-walled carbon nanotubes (MWCNTs) based MEA for neuroscience application. The effect of plasma treatment on the surface wettability of MWCNTs was examined and characterized. The H 2 O plasma treatment was utilized to modify the surface of MWCNTs from superhydrophobic to superhydrophilic. The treated recipe of power under 25 W for 10 sec could improve the electro-chemical and biological properties efficiently.

The chemical characteristics of mixed catalysts of some organic acids and aluminum sulfate have been investigated. The development of acidity is caused by the complex formation between an organic acid molecule and an aluminum ion, which has been proved by infrared spectra, proton nuclear magnetic resonance spectra, and thin-layer chromatography.

A durable sandwich wound dressing system with high liquid absorbing, biocompatibility, and antibacterial properties was designed. Various solution weight ratios of collagen to chitosan were used to immobilize on the polypropylene nonwoven fabric, which were pregrafted with acrylic acid (AA) or N-isopropyl acrylamide (NIPAAm) to construct a durable sandwich wound dressing membrane with high water absorbing, easy removal, and antibacterial activity. Swelling properties and antibacterial activity of the membranes were measured, and wound healing enhancement by skin full-thickness excision on animal model was examined. The results indicated that NIPAAm-grafted and collagen/chitosan-immobilized polypropylene nonwoven fabric (PP-NIPAAm-collagen-chitosan) showed a better healing effect than AA-grafted and collagen/chitosan-immobilized polypropylene nonwoven fabric (PP-AA-collagen-chitosan). The wound treated with PP-NIPAAm-collagen-chitosan demonstrated the excellent remodeling effect in histological examination with respect to the construction of vein, epidermis, and dermis at 21 days after skin injury. The values of water uptake and water diffusion coefficient for PP-NIPAAm-collagen-chitosan were higher than that for PP-AA-collagen-chitosan under a given solution weight ratio of collagen/chitosan. Both PP-NIPAAm-collagen-chitosan and PP-AA-collagen-chitosan demonstrated antibacterial activity.

Three new compounds, 19-hydroxylabda-8(17)-en-16,15-olide (1), 3beta,19-dihydroxylabda-8(17),11E-dien-16,15-olide (2), and 13-epi-3beta,19-dihydroxylabda-8(17),11E-dien-16,15-olide (3), together with four known compounds, 19-hydroxylabda-8(17),13-dien-16,15-olide (4), 14-deoxy-11,12-didehydroandrographolide (5), 14-deoxyandrographolide, and pinusolidic acid, were isolated from the fruiting bodies of Antrodia camphorata. The structures of compounds 1-3 were elucidated by the analysis of their spectroscopic data. The in vitro neuroprotective activity of all compounds was evaluated, and compounds 1-5 protected neurons from Abeta damage by 39.2, 35.0, 36.7, 30.6, and 27.0%, respectively, at concentrations between 5 and 20 microM.

Avoiding the on-focus photodamage and phototoxicity problem of two-photon-fluorescence excitation, harmonic generation biopsy based on a /spl sim/1300 nm light source provides a truly noninvasive and highly penetrative optical sectioning of skin.