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The ability to carry out pyrolysis of entire wood chips and rods instead of small particles would be of great value for mobile pyrolysis units, because of the large possible savings in grinding costs (7-9 % of total process costs). With this goal in mind, we designed and constructed a novel lab-scale ablative reactor for fast pyrolysis of entire wood chips and even wood rods, converting those directly into a high yield of bio-oil for the first time. The bio-oil yield from fast pyrolysis of wood chips (10 × 20 mm) was as high as 60 wt. %, similar to that from wood crumbles (2 × 2 mm). Additionally, the yield and composition of bio-oil from ablative pyrolysis were in the same range as those obtained from a fluidized bed reactor using < 1 mm particles, with the small differences (slightly lower yield and HHV, and higher water content) attributed to the longer vapor residence times in the ablative reactor, which promote secondary reactions. We modeled the heat transfer characteristics of this semi-batch system, and comparison with experimental measurements confirmed that radiation from the hot components does not significantly decompose the wood prior to direct contact with the hot metallic surface in ablative pyrolysis. The findings of this work have the potential to lead to new developments for small-scale, mobile pyrolysis units for the disposal of forest residues.

Both end-functionalized (alpha-bromo and omega-carboxy) compounds were first tested for the radical reaction on the silicon-hydride (Si-H) terminated porous silicon (PSi) with/without the presence of diacyl peroxide initiator under microwave irradiation. Then the carboxylic acid monolayers (CAMs) assembled on PSi through the robust Si-C bonds were converted to amino-reactive linker, N-hydroxysuccinimide (NHS)-ester, terminated monolayers. And finally two proteins of bovine serum albumin (BSA) and lysozyme (Lys) were immobilized through amide bonds. The optimum PSi membrane for protein immobilization without collapse, with parameters of porous radii 4-10 nm and depth 0.2-4.6 mum, was prepared from the (100)-oriented p-type silicon wafer. The chemically converted surface products were monitored with Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FESEM).

During the fabrication of poly(dimethylsiloxane) (PDMS)-based microfluidic chips, polymethylhydrosiloxane (PMHS) species in the control layer diffuse into the flow membrane, which contains polymethylvinylsiloxane (PMVS), and the components cross-link together to form the mechanically enhanced membrane. The diffusion course was investigated by using attenuated total reflectance FTIR and the improvement of mechanical properties of the flow membrane was studied by measuring the Young's modulus and the tensile strength.

Porous silicon (PSi) was applied as a supporting substrate for stepwise covalent derivatization of undecylenic acid, N-hydroxysuccinimidyl ester (NHS-ester) and nitrilotriacetic acid (NTA). By taking the advantages of porous silicon as a supporting matrix such as high surface area to volume ratio, infrared transparency, porous semiconductors for laser desorption/ionization mass spectroscopy, and low fluorescence background, a multi-mode detection biochip prototype can be realized. We prepared such a protein microarray by spotting NTA microarray dots on NHS-ester derivatized PSi, converting the rest of chip area into poly(ethylene glycol) background, loading Ni II , and finally affinity-binding histidine-tagged (His-tagged) proteins. With the multi-mode analyses of infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), matrix-assisted laser desorption/ionization mass spectroscopy (MALDI-MS), and fluorescence scanning, two example proteins, His-tagged thioredoxin-urodilatin and His-tagged aprotinin, were well qualified and quantified. porous silicon, microarray, multi-mode, NTA, His-tagged protein

We pyrolyzed entire wood chips (5×15 mm) in a new ablative reactor with the goal to evaluate the possibility to minimize grinding costs before pyrolysis. The effects of the operating parameters on the product yields and composition were investigated. Our results revealed that the bio‐oil yield in the ablative reactor was favored at a moderate pyrolysis temperature of 500 °C, low initial thickness of the wood chips layer (≤5 mm), low applied pressure on the wood chips (≤0.5 bar), and with the rotation of the bowl (≥100 rpm). The temperature profile of the wood chips indicated that the ablative pyrolysis of thick layers is limited strongly by heat transfer rates. The maximum bio‐oil yield obtained was approximately 60 wt %. The bio‐oil elemental composition was determined mostly by its water content and that of char was affected primarily by the temperature. The knowledge of how operating conditions affect the ablative process can be used in the design of continuous mobile pyrolysis units in the future.

Identified the urban soil has heavy metal pollution degree and the cause of the contamination of the overall analysis system. Through the mat lab software to realize pollution degree distribution visualization, use numerous evaluation pollution degree synthetic index methods, and then the reference neural network building the knowledge about the cause of the contamination analysis to determine the mechanism of the main causes of the pollution.

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