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The microwave absorbents of Fe and C nanoparticles as magnetic loss and dielectric loss material respectively were composited with the polyvinyl alcohol (PVA) as binder by spray granulation method. The electromagnetic parameters of Fe and C composite particles were analyzed by vector network. The complex permittivity and magnetic permeability of Fe and C composite particles matched well with increasing C nanoparticle content, and then the microwave loss property was improved. A minimum reflection loss (RL) of −42.7 dB at 3.68 GHz for a composite with 4.6 mm in thickness can be obtained when the content ratio of the C nanoparticles, the modified Fe nanoparticles and the PVA is 21:49:30 (Sample 3).

Background Rehabilitation programs before and after hip surgery can shorten the length of hospital stay, reduce the incidence of complications, and reduce the readmission rate after surgery in older adults aged 65 years or over. The present study aimed to investigate the status of readmissions within 30 days after discharge and related factors in elderly people through the big data analysis using the sample data from the National Health Insurance Service-Senior Cohort (NHIS-SC). Method The subjects of the present study were patients aged 65 years or older who underwent hip surgery between 2007 and 2012. The subjects undergoing hip surgery included those who underwent at least one surgery of the following during the period: replacement arthroplasty, revision arthroplasty, arthrodesis, internal fixation, reduction of fractured extremity and internal fixation. Each variable was selected for sociodemographic characteristics and clinical features of the subjects, and the characteristics of medical institutions according to 30-day readmission. Results Among 9008 study participants, 1628 (18.1%) were readmitted within 30 days. Lower readmission rate was associated with longer hospital stay, greater number of hospital beds, and rehabilitation before discharge; whereas a higher rate was associated with provincially located hospitals, getting of medical aid, accompanying fractures, ICU admission, and comorbidities. Conclusions Pre-discharge rehabilitation in patients aged ≥ 65 years who underwent hip surgery can reduce readmissions, and efforts to increase daily living functions such as muscle strength and walking ability are very important.

In the paper, a study on the analysis of the effects of trailing edge thickness on the aerodynamic characteristics of an airfoil is described. In this research, modification of the formula representing NACA symmetric airfoil is studied to change the airfoil shape with different trailing edge thickness of user’s choice. According to the result of aerodynamic characteristics, as the trailing edge thickness increases the maximum lift coefficient increases while the lift-to-drag ratio decreases. In this paper flow calculation results are demonstrated and the analysis on those results and findings on the effects of non-zero thickness of trailing edge are suggested.

Researches in the area of aeroacoustics have been conducted by two methods. In the first method theoretical formula or experimentation are utilized, and in the second method flow field analysis and acoustic analogy are utilized. In contrast to the first method, the second method does not need new experiments for every individual change of flow configurations and conditions, and it can predict their effects by the flow field analysis, which makes the second method preferred than the first one. In this paper numerical analysis to predict noise generated by a turbulent flow about a two dimensional circular cylinder by use of CAA (Computational Aeroacoustics) method is conducted and the results are compared to the available experimental data.

Aims Despite better overall survival in node-negative advanced gastric cancer (AGC), a significant proportion of patients develop recurrence and they may benefit from adjuvant therapy. The aim of this study was to evaluate the prognostic factors and recurrence pattern of node-negative AGC. Methods A total of 424 patients who underwent curative gastrectomy with extended lymphadenectomy for node-negative AGC between 2003 and 2005 were retrospectively reviewed. Patients with tumor involvement of adjacent organs (T4b), gastric cancer recurrence, tumor in the remnant stomach, less than 15 harvested lymph nodes, and those who received neoadjuvant chemotherapy were excluded. Results Invasion to deeper layers, undifferentiated histology, signet ring cell type compared with tubular adenocarcinoma, and tumor size larger than 6.3 cm correlated with poorer prognosis in univariate analysis. In multivariate one, however, only differentiation and depth of invasion, especially the presence of serosa involvement were significant. The 5-year survival rates of the four groups classified by differentiation and depth of invasion [T2/3 (differentiated type), T2/3 (undifferentiated type), T4a (differentiated type), and T4a (undifferentiated type)] were 98%, 92%, 80%, and 72%, respectively (P Conclusions Differentiation and serosa involvement should be considered to stratify patients with node-negative AGC for adjuvant treatment.

In this study, Jute fibers reinforced polypropylene (JFRP) composites were manufactured by injection molding technique. Prior to fabrication of composites, fiber surface was treated by Alkali and Plasma for a rise in fibers properties. Furthermore, after the alkali treatment attempt plasma treatment for the fiber surface treatment to obtain a batter value. In order to improve the affinity and adhesion between fibers and thermoplastic matrices during manufacturing, Maleic anhydride (MA) as a coupling agent have been employed. Untreated and treated surfaces of jute fibers were characterized using SEM. Tensile and flexural tests were carried out to evaluate the composite mechanical properties. Tensile test indicated that 3% of the alkali treatment and 2min plasma treatment fiber has highest tensile strength.

In this paper, our effort to apply 3-D Virtual Reality system for stereoscopic visualization of mesh data on the web is briefly described. This study is an extension of our previous and on-going research efforts to develop an automatic grid generation program specialized for wing mesh, named as eGWing. The program is developed by using JAVA programming language, and it can be used either as an application program on a local computer or as an applet in the network environment. In this research advancing layer method(ALM) augmented by elliptic smoothing method is used for the structured grid generation. And to achieve a stereoscopic viewing capability, two graphic windows are used to render its own viewing image for the left and right eye respectively. These two windows are merged into one image using 3D monitor and the viewers can see the mesh data visualization results with stereoscopic depth effects by using polarizing glasses. In this paper three dimensional mesh data visualization with stereoscopic technique combined with 3D monitor is demonstrated, and the current achievement would be a good start-up for further development of low-cost high-quality stereoscopic mesh data visualization system which can be shared by many users through the web.

Objectives: Despite compelling evidence of lipoprotein(a) [Lp(a)] as a risk factor for ischemic stroke, its underlying mechanism remains unclear. Our aim is to investigate whether serum Lp(a) level is associated with the extent and location of cerebral steno-occlusive lesions, and with large artery atherosclerotic (LAA) stroke in Korean patients. Methods: We analyzed data prospectively collected over a 3-year period on consecutive patients with stroke or TIA. Based on an angiographic study, a total of 1012 patients were classified into four subtypes: non-cerebral stenosis (n = 654), intracranial stenosis (n = 198), extracranial carotid stenosis (n = 86), and combined intracranial and extracranial carotid stenosis (n = 74). Independent associations of Lp(a) levels with the extent and location of cerebral stenosis were evaluated, and Lp(a) levels of subtypes by the TOAST criteria were compared. Results: Lp(a) levels of LAA stroke were significantly higher than those of the other four stroke mechanisms. Patients with more advanced intracranial (p = 0.001) and extracranial carotid stenoses (p = 0.001) tended to have higher Lp(a) levels. In multiple regression analysis, the third Lp(a) quartile was the strongest risk factor for isolated intracranial (OR 3.36, 95% CI 1.77–6.37) or extracranial stenosis (OR 4.82, 95% CI 1.96–11.88), whereas the fourth Lp(a) quartile was the most powerful predictor for combined intracranial and extracranial carotid stenosis (OR 4.98, 95% CI 1.92–12.91). Conclusions: Our results indicate that greatly elevated Lp(a) levels are associated with LAA stroke and extensive burden of cervicocerebral steno-occlusive lesions, which might offer indirect evidence of

The influence of concentration polarization on the pervaporation and separation of VOCs/water mixtures through the PDMS membrane was investigated, using model equation based on the resistance-in-series concept in the boundary layer in feed adjacent to the membrane surface. Dichloromethane, chloroform, 1,2-dichloroethane, and 1,1,2-trichloroethane were used as VOCs. From the permeation data of the mixtures, the overall mass transfer coefficient, mass transfer coefficient of VOCs component across the boundary layer and concentration polarization modulus as a measure of extent of concentration polarization were determined quantitatively with help of the model equations. From the analysis on the determined model parameters, the boundary layer resistance due to the concentration polarization of VOCs component contributed more to the overall permeation process than the membrane resistance did.

Objective: A high intake of fat in the diet plays a crucial role in promoting obesity and obesity-related pathologies, and especially visceral obesity is closely associated with obesity-related complications. Because adipose tissue is anatomically associated with lymph nodes, the secondary lymphoid organ, we hypothesized that fat tissue-derived factors may influence the cellularity of lymphoid tissue embedded in fat. Methods and Procedures: Mesenteric and inguinal lymph nodes were isolated from obese mice fed a high-fat diet and control mice fed a regular diet. T-cell population, activation state, and the extent of apoptosis were determined by flow cytometric analysis or terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) assay. Results: The weight of mesenteric lymph nodes and the total number of lymphoid cells in the obese mice significantly decreased compared with those in the control mice; however, no change was observed in the weight of inguinal lymph nodes. The numbers of CD4+ and CD8+ T cells in the mesenteric lymph nodes of obese mice significantly decreased compared with those of the control. Enhanced T-cell activation and apoptosis were observed in the mesenteric lymph node cells of the obese mice. The treatment of lymph node cells with free fatty acids, oxidative stress, and chylomicrons, which are obesity-related factors, resulted in lymph node T-cell activation and apoptosis. Discussion: These results suggest that visceral fat accumulation with a high-fat diet can cause the atrophy of mesenteric lymph nodes by enhancing activation-induced lymphoid cell apoptosis. Dietary fat-induced visceral obesity may be crucial for obesity-related immune dysfunction.

The zinc oxide(ZnO) nanowires were deposited on Si(001) substrates by thermal chemical vapour deposition without any catalysts. SEM data suggested that the grown nanostructures were the well-aligned ZnO single crystals with preferential orientation. Back-gate ZnO nanowire field effect transistors(FET) were successfully fabricated using a photolithography process. The fabricated nanowire FET exhibits good contact between the ZnO nonowire and Au metal electrodes. Based on I-V characteristics it was found out that the ZnO nanowire revealed a characteristic of n-type field effect transistor. The drain current increases with increasing drain voltage, and the slopes of the curves are dependent on the gate voltage.

SummaryIn this study we have investigated the efficiency of in vitro maturation (IVM) as a basic way to study the development of canine oocytes after in vitro fertilization (IVF). We decided, therefore, to perform two-part experiments. Firstly, experiment I compared the effects of TCM199 without fetal bovine serum (FBS) with TCM199 supplemented with 5% FBS on the in vitro nuclear maturation rate of canine oocytes. For the efficiency of meiotic development to the metaphase II (MII) stage, we found that 4.7% (4/64) of all oocytes grown in TCM199 without FBS developed to the MII stage compared with only 1.7% (1/59) of those grown in TCM199 with 5% FBS for 48 h. Therefore, FBS did not increase in vitro nuclear maturation. In experiment II, the cleavage rate of canine oocytes used for IVF was investigated following heparin treatment. Canine oocytes were fertilized in four groups: Fert–TALP medium without heparin (Fert I) or Fert–TALP medium supplemented with 10, 20 or 30 µg/ml heparin (Fert II, Fert III, Fert IV, respectively). Oocytes that were grown for 24 h in Fert I following fertilization showed the highest rate of all of the groups, 6.5% (5/77) and developed to the early morula stage. Markedly, the oocytes cultured in Fert I for 24 h following insemination had a higher rate of embryonic development than other groups. We can assert that, unlike findings in other mammals, heparin treatment in canine IVF does not increase the efficiency of the fertilization rate and is therefore not an important factor.

In this paper, we fabricated TCO (transparent conductive oxide) electrode on flexible substrate in order to study effects of electrical and optical properties according to Al-doped ZnO(AZO) film thickness. The thickness of film was from 100 nm to 500 nm and was controlled by changing deposition time. We used High Resolution X-ray Diffractometer (HR-XRD) to analyze crystal structure and UV-visible spectrophotometer to measure property of optical transmittance, respectively. The surface images are obtained by using ESEM (Environment Scanning Electron Microscopy). In this experiment, all the AZO films deposited on flexible substrate show high transmittance over 90% and especially in the films with 400 nm and 500 nm thickness, the resistivity () and optical bandgap energy (3.61 eV) are superior to the other films.

Background De novo malignancy is not uncommon after liver transplantation (LT). Gastric cancer is one of the most common malignancies in both the Korean general population and LT recipients, and colorectal cancer prevalence is gradually increasing. Methods Among 3690 adult recipients who underwent LT from January 1999 and December 2013, the screening patterns and prognosis of 26 cases of gastric cancer and 22 cases of colorectal cancer were analyzed. Results For gastric cancer, the mean patient age was 54.6 ± 6.2 years at LT and 59.5 ± 6.7 years at cancer diagnosis, with a post-transplant interval of 60.2 ± 29.8 months. Patients were divided into regular (n = 18) and non-regular (n = 8) screening groups, with early cancer found in 14 and 0 patients; their 2-year survival rates after cancer diagnosis were 93.1% and 33.3% (P = .006), respectively. Endoscopic resection was successfully performed in 8 patients, all in the regular screening group. For colorectal cancer, the mean patient age was 53.3 ± 6.1 years at LT and 58.1 ± 6.7 years at cancer diagnosis, with a post-transplant interval of 54.3 ± 38.0 months. Patients were divided into regular (n = 19) and non-regular (n = 3) screening groups, with early cancer found in 12 and 0 patients; their 2-year survival rates after cancer diagnosis of 92.3% and 33.3% (P = .003), respectively. Endoscopic resection was successfully performed in 6 patients, all in the regular screening group. Conclusions LT recipients are strongly advised to undergo regular screening studies for various de novo malignancies, especially cancers common in the general population. Regular endoscopic screening contributes to the timely detection of gastric and colorectal cancers, improving post-treatment survival outcomes.

This chapter discusses a cloaking algorithm called TL-diversity that produces a cloaking area by considering both the number and type of buildings within the cloaking area. The proposed TL-diversity strengthens the privacy protection of the querying user by additionally maintaining the diversity with regard to the types of buildings in a cloaking area. The TL-diversity initially finds a cloaking area based on L, the number of buildings specified by the querying user, and then enlarges the cloaking area by including more buildings until TL, the number of different types of buildings specified by the user, is satisfied. The size of the cloaking area created in a setting where the clients are densely populated is generally small so an adversary can easily infer the client locations. In location-based services (LBS), users send queries to the LBS servers along with their locations, but this location information can be maliciously used by adversaries.

Aluminium doped zinc oxide (ZnO:Al) films were deposited on glass substrate by DC magnetron sputtering from a ZnO target mixed with a various wt% Al2O3. The lowest resistivity of 8.54×10−4 Ω cm as well as over 90% of optical transmission of the ZnO:Al film was obtained with a 2 wt% Al2O3 doped ZnO target for the following processing conditions: substrate temperature of 400 ∘C; discharge power of 40 W; Ar pressure of 1 mtorr. In order to reduce the electrical resistivity, positive and negative biases (−60 V to +40 V) were applied to the substrate. We report the effects of substrate bias on the structure, deposition rate, electrical properties, and optical transmission of ZnO:Al thin films. Films deposited with either positive or negative bias have strong (002) preferred orientation. The electrical resistivity of the film decreases significantly as either the positive or negative bias increases. However, as the positive and the negative bias increases over 30 V and −40 V, the resistivity decreases. Films with electrical resistivity as low as 4.3×10−4 Ω cm and optical transmittance of 91.5% were obtained with a substrate bias of +30 V.

This study was carried out in order to understand the early diagenetic redistribution of phosphorus and relevant mass balance in the sediments of the East Sea. In two cruises during May 1993 and October 1995, 11 box cores were collected in the southwestern part of the East Sea. Dissolved phosphorus and iron were analyzed in the porewater from the cores. Sediment samples were analyzed for solid-phase P species and solid-phase Fe oxyhydroxide by sequential extraction. Phosphorus speciation results show that organic P is the major chemical form of phosphorus in young sediments within the upper 50 cm of sediment. However, the authigenic fraction of total P increases with depth, indicating the precipitation of carbonate fluorapatite (CFA) in the sediments. The authigenic CFA (Ca5(PO4)2.6(CO3)0.4F) was formed and buried at rates of 11–110 μmol cm−2 kyr−1. The main source of dissolved phosphorus for the precipitation of CFA is organic P. Dissolved phosphorus, released from the decomposition of organic P, diffuses upward to return to bottom water, or is sorbed to iron oxides in the oxidized sediments. As sedimentation proceeds, the iron oxide-bound P is released in the reduced layer and enters the dissolved phase, which contributes P to the formation of CFA in addition to that contributed by the organic P. The burial flux of reactive P (iron oxide-bound P+authigenic P+organic P) is 0.09–0.53 g P m−2 yr−1 that accounts for 18–58% of the reactive P arriving at the sediment/water interface. The burial flux of reactive P is high in the upper and lower continental margin sediment. The burial flux of reactive P in the Ulleung Basin sediment is less than those in the continental margin sites by a factor of 6, indicating that the reactive P burial flux is mainly dependent on sedimentation rate.

The characteristics and operation of a GaN Schottky diode-based remote sensing system for hydrogen is described. The detection mechanism is a change in effective barrier height of the Pt or Pd contact on the GaN in the presence of even 600 ppm of H 2 This translates to a change in forward current at fixed bias voltage or a change in voltage across diode at fixed bias current, which means a change in impedance. The change in sensor impedance is amplified and the signal is transmitted at 916 MHz to a remote receiver base station. The base station response can be set to many possibilities, including alarms for signals above a particular threshold. The sensor output increases with ambient temperature due to increased cracking efficiency of the hydrogen on the Pt or Pd surface.

We carried out a three-dimensional vector measurement of a somatosensory evoked field (SEF) with an electric stimulus to the right thumb, using three-dimensional second-order gradiometers connected to 39-channel SQUIDs, which can detect magnetic components perpendicular to the scalp (Br) and tangential to the scalp (BΘ, Bφ) simultaneously. A dynamic singular value decomposition method, with a time window and shift time, was applied to spatio-temporal magnetic data. First, averaging of the SEF data with a dynamic SVD was done with each trigger for stimulation. Second, dynamic SVD was applied to SEF data, having two frequencies ranges (1-80 Hz and 15-80 Hz), and with a time window of 10 ms and which was shifted every 1 ms in analysis. Two dominant singular values were obtained for the contralateral magnetic component in 90 to 110ms. Source localization of SI and SII activity with a ECD method showed dominant GOF (goodness of fitness) around 90ms. We concluded that the proposed dynamic SVD method, with a time window and shift time, is useful for reducing noise component in SEF data and discriminating multiple sources overlapping in time.

The main purpose of this paper is to investigate numerically the effects of solidification on the heat transfer characteristics of the liquid metal layer, for use in accident analyses. The situation is very similar to an overlying liquid melt pool that could be fooned in the reactor lower head during the late phase of a severe nuclear accident. Based on a computational model, MPCOOL, the numerical predictions were then assessed through a comparison with the experimental data that was obtained with various boundary temperature conditions and geometrical aspect ratios, especially for the Ra-Nu relationship. For the cases with solidification, the results of the comparison show that(a) the computational model does show a good agreement with heat transter rates inferred from the experimental data, with a few exceptions at the Ra numbers which suggest a turbulent transport; and also (b) the computational model underpredicts the heat transfer rates by about 6% than that inferred from the experimental data when it is integrally evaluated with the Ra-Nu correlation. The foregoing results are mainly due to the currently limited applicability of the computational model up to the laminar-to-turbulence transition flows and its application to the turbulence flows because it is always subjected to a model uncertainty between the laminar and turbulence. Next, an additional comparison for the cases with and without solidification was made to examine the effects of the solidification on the energy partition within the liquid metal layer and its effects on the directional heat transfer rates. The results of the comparison show that the computational model for the case without solidification predicts higher heat transfer rates by about 15% than when solidification is included, but there isn't any experimental data that directly supports this trend.

Plasma nitriding on simultaneously Al-Cr diffusion-treated AISI H13 and AISI 403 steel was performed and analysis of microstructure, microhardness, cyclic oxidation behavior and high temperature wear resistance of these duplex-treated steels was made. The results were compared with those from steels treated by either plasma nitriding or by duplex treatment of single element (Al) diffusion and plasma nitriding. Both steels showed a FeAl compound layer of approximately 350 μm thickness on the surface after simultaneous diffusion coating and nitrided layer of approximately 70∼80μm formed after the subsequent plasma nitriding process. The microhardness was significantly improved by the duplex surface treatment (approximately 1500∼1600 Hv(0.5N)) more than only by plasma nitriding (approximately 1000∼1100 Hv(0.5N)) by a factor of 1.5 to 1.6. In addition the duplex treated specimens showed a much-improved high temperature wear resistance. Results from the cyclic oxidation test at 1173K showed that much improved oxidation resistance could be observed from the specimens treated by Al-Cr diffusion and plasma nitriding and this could be attributed to formation of a Cr 2 O 3 layer as an additional protective layer on the surface.

BACKGROUND AND PURPOSE: Crossed cerebellar diaschisis, not only a secondary result of supratentorial infarction but also an indicator of clinical outcomes, has frequently been reported on PET and SPECT but has been rarely described with arterial spin-labeling MR imaging. The purpose of this study was to determine the ability of arterial spin-labeling MR imaging to evaluate crossed cerebellar diaschisis compared with that of SPECT. To our knowledge, this is the first study to validate arterial spin-labeling in crossed cerebellar diaschisis by using SPECT as a reference standard. MATERIALS AND METHODS: This study included 16 patients in whom crossed cerebellar diaschisis was shown on SPECT and 10 control subjects in whom crossed cerebellar diaschisis was not shown on SPECT. During the qualitative analysis, asymmetric cerebellar perfusion on arterial spin-labeling was divided into 1 of the following 3 grades by 2 blinded observers: the affected cerebellum was isointense compared with the unaffected cerebellum (grade I), it was slightly hypointense (grade II), or it was markedly hypointense (grade III). In the quantitative analysis, asymmetry indices were calculated by using SPECT and arterial spin-labeling images. For statistical analysis, κ statistics, the interobserver correlation coefficient, the independent t test, Pearson correlation, and linear regression analysis were used. RESULTS: Almost all the diagnoses of crossed cerebellar diaschisis on SPECT were noted on arterial spin-labeling in both qualitative and quantitative analyses with good interobserver agreement (κ = 0.961; interobserver correlation coefficient, 0.806). The mean asymmetry index of arterial spin-labeling (26.06 ± 9.00) was significantly larger than that for SPECT (15.28 ± 5.34; P < .001). There was a significant positive correlation between the asymmetry indices obtained for SPECT and those for arterial spin-labeling (r = 0.77 [95% CI, 0.443–0.916]; P < .001). The relationship of asymmetry indices between SPECT and arterial spin-labeling (x, y) was calculated as y = 6.2131 + 1.2986x (R(2) = 0.592; P < .001). CONCLUSIONS: Arterial spin-labeling can be a noninvasive alternative to SPECT for evaluating crossed cerebellar diaschisis.

Between 2003 and 2005, a total of 11,716 samples were collected and analysed to determine the level of pesticides residues. Multi-residue methods (MRMs) capable of simultaneously determining 250 pesticides were used. Of the 11,716 samples, 89.1% had no detectable residues and 1.7% had violative residues. The detection rates by commodity group were 11.4, 8.6, 0.3, and 0.02% for vegetables, fruit, grain, mushrooms, and the others, respectively. Agricultural products with pesticide residues were pepper, Perilla frutescens, leafy lettuce and spinach in decreasing order. Of the 250 pesticides that were monitored, 70 pesticides were actually found. Procymidone, endosulfan, chlorfenapyr, metalaxyl, and diethofencarb were frequently detected. Of the samples, parsley, Petasites hybridus, Aster scaber and leek had high violative rates of 23.1, 12.6, 8.2, and 7.9%, respectively. From violative samples, procymidone, endosulfan, metalaxyl, diazinon and chlorpyrifos were frequently detected. The violation rates were 1.71, 1.68, and 1.76% in 2003, 2004 and 2005, respectively, and the detection rates were 8.5, 12.0, and 13.3% in 2003, 2004, and 2005, respectively.

A theoretical and experimental study was performed to examine the water spray method of ice slurry production. First, the conditions for the formation of ice particles were investigated theoretically by the diffusion-controlled evaporation model. The prediction of the model was proved to agree relatively well with experiments in which we examined the conditions for a droplet of initial temperature 20°C and size 50 μm to change into an ice particle in a chamber of height 1.33 m. Second, the production of cold storage heat will increase almost proportionally to the number of spray nozzles because no substantial difference was found in the Sauter Mean Diameter (SMD) of sprays from single and twin nozzle. Third, an ice slurry was experimentally obtained by spraying droplets of 7% ethylene glycol aqueous solution in a vacuum chamber where pressure is maintained below the freezing point of the solution. Finally, based on the theoretical and experimental results, we propose an optimizing chart for providing the operating conditions to make ice slurry using the relations of the staying time of the droplet in the chamber, the injection pressure, the spray droplet size and the chamber pressure.

A novel permeation apparatus was developed which can make the on-line measurements of both flux and permeate composition. The development of the apparatus was motivated by the desire to measure flux transients, directly, rapidly and precisely. The apparatus was improved by solving the problems associated with the drawbacks in the continuous-flow technique. The transient measurements also allow the diffusion coefficient and concentration of a permeant in membrane to be rapidly determined. The apparatus performance was illustrated by conducting the pervaporations of water through a hydrophilic poly(vinyl alcohol) and a hydrophobic poly(dimethylsiloxane) membranes, respectively. A comparison of fluxes determined by the on-line measurement was made with those measured by the conventional method in which the permeate vapours were collected by liquid nitrogen for analysis. The diffusion coefficients and concentration of water in the membranes were determined from the flux transients and they were coincident with values in a literature. It was confirmed that fluxes with time could be measured precisely and rapidly with the apparatus.

Corn starch after cross-linking with POCl 3 (1%, v/w, starch db) was carboxymethylated with sodium chloroacetate (5–20%, v/w, starch db) to examine the metal removal activity of the starch from water. The cross-linked carboxymethyl starch [degree of substitution (DS) 0.02–0.08] was dispersed (0.5–3.0%) in aqueous solutions of divalent metal ions (Cu, Pb, Cd and Hg, ∽200 ppm), and the starch–metal complex was filtered. Removal efficiency of the metal ions from their aqueous solutions increased proportionally with the DS of the carboxymethyl group and the starch content in the solution. Ionization of the carboxymethyl groups in starch was necessary for the effective metal removal. When the starch pH was adjusted below 4.0 after carboxymethylation, the starch was no longer an effective metal binder. The metal ions interacted with starch, 10 min after the starch was added. Lead, cadmium, and mercury ions in water were almost completely removed when 1% starch (DS 0.081, pH 6.0) was used. Under the same conditions, copper concentration was reduced from 203 to 71 ppm. Starch could be recovered by washing the metal ions from the complex with weak acid (pH 2.0) although the metal-binding activity of the starch was slightly reduced by this process.