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Fillers with different chemical properties were used to study their effects on poly(vinyl acetate) (PVAc) emulsion wood adhesives. The elastoplastic behaviour of the filler treated PVAc emulsions was studied using differential scanning calorimetry and dynamic mechanical thermal analysis. The results show that the glass transition temperature (Tg) of the polymer is not changed significantly by the addition of the fillers, while the tensile modulus is changed together with the hardness and stiffness. The viscosity of the emulsions and their performance on wood surfaces are greatly affected by fillers. Fillers with high oil‐absorption capacity increase viscosity to a greater extent. The acidity of the fillers influences the setting time for bonding of the emulsions to wood, and the water resistance, since some chemical reactions can take place during curing.

We report a widely tunable distributed Bragg reflector (DBR) laser, in which InGaAsP with 1.4- $\mu \text{m}$ photoluminescence wavelength is butt-jointed as the DBR section material. A titanium (Ti) thin-film heater is integrated in the DBR section of the device. With the help of the tuning effect of the heater, an over 20-nm wavelength tuning range is obtained. The DBR laser is a promising light source for future wavelength division multiplexing passive optical networks.

2-Furyloxirane(FO) with purity of over 99% was prepared in 80% yield by epoxidation of furfural with trimethylsulfonium chloride and potassium hydroxide in acetonitrile/water solution. Polymerization of FO was realized using tri-isobutyl aluminum (Al(i-Bu)3) as catalyst, when Al(i-Bu)3 concentration was 0.009 mol/L, poly(2-furyloxirane)(PFO) with M n of 3.4 kg/mol and a polydispersity index of 1.5 was obtained in yield of 88% after polymerization at 25 °C for 48 h. The corresponding PFO showed glass transition temperature (T g ) of Ca. 1 °C and 5 wt% thermal decomposition temperature(T d ) of 260 °C. The obtained PFO was almost 100% head-to-tail structure, and it was a good plasticizer and thermal stabilizer for poly(propylene carbonate)(PPC), an alternate copolymer of propylene oxide and carbon dioxide. For PFO/PPC polyblend with PFO loading of 2 wt%, its T d increased by 50 °C from 214 °C of pure PPC to 264 °C, while its elongation at break increased from 13% of pure PPC to 29%.

Purpose Evaluation of peripheral retinal vascular changes in anterior uveitis using ultra-wide-field fluorescein angiography. Design A prospective, observational study of a case series of patients diagnosed with anterior uveitis. Methods Setting: Clinical observation at an academic medical center. Patient or Study Population: A total of 65 eyes of 33 patients corresponded with the research criteria of anterior uveitis in the opinion of specialists of Peking University First Hospital. Observation Procedures: Patients were diagnosed primarily through clinical examinations and conventional fluorescein angiography. Subsequently, ultra-wide-field fluorescein angiograms were obtained for each patient. Main Outcome Measures: The main outcome was the detection of peripheral retinal changes by ultra-wide-field fluorescein angiography, and how these changes influenced the evaluation and management of the disease. Results Peripheral vessel leakage was detected in 27 eyes (42%) with anterior uveitis, of which 15 eyes displayed active inflammation and 12 eyes displayed inactive inflammation. Peripheral vessel leakage was found in seven of eight eyes with cystoid macular edema. Cystoid macular edema was detected in 7 of 27 eyes (26%) with peripheral vessel leakage, whereas 1 of 38 eyes (3%) did not display peripheral vessel leakage (p

A novel design of a two-mode de/multiplexer (DE/MUX) based on multimode interference (MMI) couplers is presented. Instead of the phase shifter (PS) in the shape of a narrow strip waveguide, which needs tight design and fabrication requirements, a tilted joint is used as a PS in the proposed device, so that the effects of the fabrication errors of the PS on the performance of the device can be reduced greatly. Simulations show that while the size of the device is as small as 39.54 μm, which is more compact than other MMI-based DE/MUX, the fabrication tolerance is larger than ±25 nm. Within the entire C-band wavelength range, the de-multiplexing crosstalk of the device is lower than -28 dB and the insertion loss is below 1.0 dB.

We present an InP based distributed Bragg reflector (DBR) laser transmitter which has a wide wavelength tuning range and a high chip output power for wavelength division multiplexing passive optical network (WDM-PON) applications. By butt-jointing InGaAsP with 1.45 µm emission wavelength as the material of the grating section, the laser wavelength can be tuned for over 13 nm by the DBR current. Accompanied by varying the chip temperature, the tuning range can be further enlarged to 16 nm. With the help of the integrated semiconductor optical amplifier (SOA), the largest chip output power is over 30 mW. The electroabsorption modulator (EAM) is integrated into the device by the selective-area growth (SAG) technique. The 3 dB small signal modulation bandwidth of the EAM is over 13 GHz. The device has both a simple tuning scheme and a simple fabrication procedure, making it suitable for low cost massive production which is desirable for WDM-PON uses.

Ram is a very important component of super-heavy-duty computer numerical control (CNC) floor type boring-milling machine, and deformation of ram is a significant source causing errors in machining process. To compensate the deformation error of super-heavy-duty CNC floor type boring-milling machine, based on force analysis theory, the law and compensation measures of deformation of ram are researched. Based on the principle of torque (force) balance of the ram components, the formulas of compensation forces and compensation torques are derived, the relations between compensation forces (compensation torques) and the stroke distance of the ram are given. According to theoretical analysis results and the structural characteristics of super-heavy-duty CNC floor type boring and milling machine of TK6932, rods compensation, hydrostatic pressure compensation and wire rope compensation measures are taken to compensate the deformation error of ram. The experiments and computer simulation results show that the straightness of the ram at its overhanging end meets the national machinery industry standards.