Water-borne CO₂-based polyurethanes with excellent mechanical performance and hydrolysis/oxidation resistance are prepared from CO₂.

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

Whole-procedure solvent-free preparation of CO₂-WPU was accomplished by direct dispersion the prepolymer at an elevated temperature.

Controllable synthesis of a narrow polydispersity oligo(carbonate-ether) tetraol provided new relationship between the acidity (p<italic>K</italic>_a1 value) chain transfer agent and catalytic mechanism in initial stage.

Due to the concern on residue toxic metal in biodegradable poly(propylene carbonate) (PPC), soil tolerant and heavy free aluminum complexes, that is, bifunctional porphyrin catalysts bearing quaternary ammonium salts ligand framework were prepared. Variation of anion axial had dramatic effects catalytic activity resultant complex, among which complex 3b yielded perfectly alternative PPC with high molecular weight relatively narrow polydispersity, its TOF reached 3,407 h−1 at [PO]/[cat.]...

Cationic waterborne polyurethane (CWPU) was initially developed as a specific adhesive for anionic surface but now is ubiquitous in innovative material systems such poly(ionic liquid)s, polyelectrolytes, antibacterial coatings, and drug carriers. However, state-of-the-art CWPU faces imperative challenges like easy degradation poor water resistance, which caused by excessive incorporation of internal emulsifiers with tertiary amines into the backbone than necessary, since emulsification...

A novel aliphatic polycarbonate from renewable resource was prepared by copolymerization of furfuryl glycidyl ether and CO2 using rare earth ternary catalyst; its number-average molecular weight (Mn) reached 13.3 × 104 g/mol. The copolymer (PFGEC) easy to become yellowish at ambient atmosphere due postpolymerization cross-linking reaction on the furan ring; gel content 17.2 wt % after 24 h exposure air room temperature. PFGEC could be stabilized addition antioxidant 1010 (tetrakis[methylene...

Preactivation: an interesting means to shorten the copolymerization time of CO₂-based polyols synthesized by strongly acidic but cheap oxalic acid.

We report a widely tunable distributed Bragg reflector (DBR) laser, in which InGaAsP with 1.4- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> photoluminescence wavelength is butt-jointed as the DBR section material. A titanium (Ti) thin-film heater integrated of device. With help tuning effect heater, an over 20-nm range obtained. The laser promising light source...

We present designs of wavelength-division-multiplexing (WDM) and mode-division-multiplexing (MDM) optical links using mode de/multiplexers (DE/MUXs) based on multimode interference (MMI) couplers with a tilt joint as phase shifter. The properties WDM-MDM three wavelengths two modes are numerically studied by 3-D beam propagation method. In the first design, wavelength combiner is also an MMI coupler type. insertion loss design around 6 dB because inherent combiner. size main passive parts...

We present an InP based distributed Bragg reflector (DBR) laser transmitter which has a wide wavelength tuning range and high chip output power for division multiplexing passive optical network (WDM-PON) applications. By butt-jointing InGaAsP with 1.45 µm emission as the material of grating section, can be tuned over 13 nm by DBR current. Accompanied varying temperature, further enlarged to 16 nm. With help integrated semiconductor amplifier (SOA), largest is 30 mW. The electroabsorption...

The motion control of robot manipulators is a crucial problem concerning automatically controlled robots. In this work, the model predictive method with an integral compensation (MPC-I), which compensates for matched uncertainties due to unmodeled dynamics, proposed solve trajectory tracking in joint and task spaces. First, paper decouples variables manipulator using computed torque method. MPC-I is, thereafter, derived realize space. To space, space converted into executed, afterward,...

Various modifications of polyvinyl acetate emulsion wood adhesive were made and their performance evaluated in standard tests. The results are interpreted the context adhesion theories chemical structures polymers wood. to cohesive strength two predominant factors determining adhesives. Adhesive thermosetting resins is enhanced by irreversible reactions that create extensive networks within layer strong bonds substrate, leading durable joints passed all evaluation Most PVAc emulsions...

A near-neutral waterborne cationic polyurethane from CO₂-polyol was synthesized using BDE as an internal emulsifier. Its compatibility with aqueous cPANI dispersion and strong adhesion to CS plates mean it could be used for corrosion protection.

In this paper, we propose a new path planning algorithm based on the probabilistic roadmaps method (PRM), in order to effectively solve autonomous of mobile robots complex environments with multiple narrow channels. The improved PRM mainly improves density and distribution sampling points channel, through combination learning process APF algorithm. We also shortened required time length by optimizing query process. first key technology improve involves number free collision-free lines...

Four different approaches were taken to improve the water resistance of poly(vinyl acetate) (PVAc) emulsion adhesives. The improved wood adhesives tested according ISO 9020 standard. Tensile storage modulus (E') and glass transition temperature polymer films measured using dynamic mechanical thermal analysis quantify influence on those variables. Gel fraction swelling ratio film evaluate internal crosslink density. experimental results showed that blending melamine/urea/formaldehyde (MUF)...

In order to protect people’s lives and property, increasing numbers of explosive disposal robots have been developed. It is necessary for an ordinance (EOD) robot quickly detect all explosives, especially when the location explosives unknown. To achieve this goal, we propose a bidirectional dynamic weighted-A star (BD-A*) algorithm learn memory-swap sequence particle swarm optimization (LM-SSPSO) algorithm. Firstly, in BD-A* algorithm, our aim obtain shortest distance path between any two...

We present the fabrication of a low-cost multiwavelength laser array monolithically integrated with passive optical combiner for line terminals (OLTs) in wavelength-division multiplexing (WDM) networks (PONs). By combining upper separate confinement heterostructure layer selective area growth technique and bundle guide technique, both emission highly uniform spacing low-loss passive-waveguide material can be obtained single metal–organic chemical vapor deposition (MOCVD) step, which greatly...

Modifications of poly(vinyl alcohol) (PVA) can improve the properties and performance acetate) (PVAc) emulsions stabilized with these modified colloids. Water resistance toughness as wood adhesives be achieved through chemical reactions hydroxy groups colloid various modifiers. The changes carried out either in preparation PVA hydrolysis copolymers vinyl acetate other monomers, or by reaction modifiers aqueous solutions. PVAc show better than those conventional tests applications. colloids...