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The liquefaction of cellulose in the presence of phenol without or with sulfuric acid as catalyst was investigated. The liquefied products were characterized by GC/MS and FTIR. Results showed that reaction temperature and reaction time had obvious effects on liquefaction of cellulose. Sulfuric acid showed an excellent catalytic degradation. The chemical compositions of the liquefied products produced using sulfuric acid catalyst or not were almost identical, and the majority of the identified liquefied products were methylene bisphenol and its isomers. During the process of liquefaction, the degradation of cellulose and condensation polymerization occurred at the same time. The last liquefied products were greatly dependent on the reaction conditions.

The resol-type resin was prepared with a high yield from the liquefied products of walnut shell in phenol, which was reacted with formaldehyde under low alkaline conditions. The effects of reaction temperature and time on the yield and viscosity of the resol resin were investigated. Results showed that the optimum resol resinification conditions were a reaction temperature of 80°C and a reaction time of 2 h. The biomass-based resol resin from liquefied products of walnut shell was successfully applied to produce phenolic foam with diisopropyl ether as the blowing agent, Tween 80 as the surfactant and hydrochloric acid as the catalyst, respectively. The obtained foams showed satisfactory mechanical properties and a uniform fine cellular structure.

Curing is the key to the bonding, this paper considered the production practice, studied the curing properties of different MUF resin under the different curing agent with DSC. The experimental results show that: The characteristics temperature of curing reaction is closely related to the β. With the increase of β, the initial and peak temperature is moving to the high-temperature, the curing time became shorter; the range of curing temperature became much wider. At the same time, the curing peaking temperature was decreased and the Enthalpy integral of curing reaction was reduced first then increased with the increased of the amount of curing agent. When the amount of curing agent occupied 4.0%-6.0% of the MUF resin, the pH was decreased mostly, and the curing reaction rate run up quickly Along with the increasing of n (F): n (U1), the To, Tp and Ti are going ahead distinctly after hardening. At the same time, both activation energy and reaction order are all decreased, absorbed heat is dropping too. So, curing technics became easily.

The liquefaction of corncob in polyhydric alcohols was investigated by using sulfuric acid as a catalyst. Results showed that the best liquefaction could be obtained with residue percent of 4.5% under the conditions with the corncob/polyhydric alcohols mass ratio of 1/5, reaction temperature of 150°C, reaction time of 60 min, catalyst amount of 3% (based on the weight of corncob), PEG 400/glycerin mass ratio of 7/3 in the polyhydric alcohols, respectively. The liquefied liquid products had acid number of 18.9 mg KOH/g and hydroxyl number of 616.3mg KOH/g, respectively.

Obstructive Sleep Apnea Syndrome (OSAS) is the most common sleep-disordered breathing medical condition and a potentialy life-threatening affliction. Upper airway defense is based on the secreted mucus. The primary factors involved in the airway surface liquid (ASL) are not completely understood. In this study, identification of ASL proteins was demonstrated by using proteomic approach. 30 OSAS patients and 15 normal subjects between the ag e s of 30 and 50 (males=23; females=22) underwent collection of ASL sample. Proteomic approach involving two-dimensional polyacrylamide gel electrophoresis (2D PAGE) and mass spectrometry (MS). Querying the SWISSPROT database with the MS data yielded the identity of 10 proteins in the spots. Three of these proteins showing significant difference in abundance were identified to be Carbonic Anhydrase VI, immunoglobulin (Ig) heavy chain, and Calgranulin A. Overal, differential expression of proteins in the A S L proteome of OSAS patients suggests that the hypoxia associated with OSAS may lead to changes in catabolism of these proteins and their excretion in ASL.

Objective To study the modeling method of animal model of upper stenosis-airway of rats and air flow characteristic. Methods Totally 30 3-month old rats were randomly divided into a control group and a model group. Sodium Hyaluronte 0.1ml was injected into mucosa of the soft palate and the uvula of each rat from the model group in the anesthetic state. After 3-month feeding under the same conditions, the two rat groups were carried out CT Scanning and respiratory experimental examinations, respectively. The Computational Fluid Dynamic Method was then employed to simulate the airflow in upper airway. The flow characteristics are compared between a control rat and a model rat. The minimum cross sectional area of pharyngeal of the model group rats was reduced remarkably than that of the control group, which implies that the airway of the model rats is significantly narrower than that of the control rats with a P-value P

We aimed to investigate metabolic parameters in children with adenoid hypertrophy (AH) only or adenotonsillar hypertrophy (ATH) and compare them with healthy controls.Forty-four prepubertal children aged 6-12 years who were obstructive symptoms and 16 healthy children were recruited in this study. All children underwent a complete otolaryngologic examination and sleep screening. The patients were divided into three groups according to obstruction type: normal, AH (adenoid grade III or IV, tonsil grade 1 or 2), and ATH (adenoid grade III or IV, tonsil grade 3 or 4). All participants underwent hematologic and biochemical tests including fasting blood glucose, insulin, and plasma lipids.(1) The children with AH and ATH had lower high-density lipoprotein cholesterol (HDL-C), when compared to normal children. (2) The level of HDL-C was negatively correlated with the sum of adenoid and tonsillar size scores and the apnea-hypopnea index (AHI) (r=-0.477, p0.001 vs. r=-0.548, p0.001, respectively). There was a modest association between HDL-C and minimal SpO₂ (r=0.332, p=0.009). (3) Stepwise multiple regression analysis identified the AHI, triglycerides, and fasting insulin as independent predictors for HDL-C.Patients with adenoid and tonsil hypertrophy had low HDL-C. HDL-C levels are inversely related to the sum of adenoid and tonsillar size scores and AHI in SDB children. HDL-C may be a sensitive indicator of serum lipids changes in SDB children.

Design methodology, COM (Coupling-of-mode) model simulation and experiment results for a low loss 3-stage ladder type IF SAW filter are presented. To enhance electrode mass loading, Au-Ge-Ni alloy (density is 5 times that of aluminum) is used instead of traditional Al electrode. 36/spl deg/ Y-X LiTaO/sub 3/ is used as substrate material. Different electrode thickness (4.5% to 11.2% of a wave length with Al electrode) is simulated to estimate the frequency responses and then filters were fabricated on 36/spl deg/ LT for comparing the results. When the electrode thickness is 2000/spl Aring/ (about 0.9% of a wave length with Au-Ge-Ni electrode, it's corresponding to 4.5% of a wave length with Al electrode), the center frequency is around 204MHz, the insertion loss is near 2.7dB, out-of-band rejection is around 15dB, and there is a large pitch in the center of pass-band. When electrode thickness increases, pass-band ripple and bandwidth becomes smaller, center frequency moves from 204 MHz toward 197MHz, and insertion loss increases. When the electrode thickness is 4800/spl Aring/(about 2.24% of a wave length with Au-Ge-Ni electrode, it's corresponding to 11.2% of a wave length with Al electrode), the center frequency is around 197MHz, the insertion loss is near 4.3dB, out-of-band rejection is around 17dB, and the center of pass-band is flat. The same results can be gotten with the simulated COM program. When the thickness increases, pass-band becomes smooth. Filter response is better when the electrode thickness is greater than 7% for Al electrode, but it is only greater than 1.4% for Au-Ge-Ni electrode. So, for ladder-type IF SAW filter, it is better to use Au-Ge-Ni electrode instead of Al because lift-off process could be done easily. But when the electrode is too heavy, filter shape will be damped because of mass loading.