Preparation and properties of nonionic polyol dispersion from terpinene‐maleic ester‐type epoxy resin

A nonionic epoxy‐based polyol (NTP) which can be used in place of the commonly used polyol dispersions to prepare two‐component waterborne polyurethanes was synthesized with terpinene‐maleic ester‐type epoxy resin (TME), polyethylene glycol (PEG), and trimethylopropane (TMP) in the presence of sulfuric acid as catalyst. The synthesis process was tracked with gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) by investigating the changes of molecular weight and glass transition temperature (T_g) of the product. FTIR was used to characterize the chemical structure of NTP. Major technical parameters of NTP were as follows: hydroxyl value 100 mg/g, hydroxyl group content 3.04%, T_g 4.03°C, and viscosity 150 mPa s (40% solid content). Effect of molecular weights and dosages of PEG on stability of NTP dispersion was examined by particle size analyses. It was found that stable dispersion was obtained when using PEG6000 as hydrophilic chain and its dosage ≥8% by the weight of TME. The average particle size of the prepared dispersion was about 200 nm from particles size and TEM analyses. The NTP dispersion showed characteristic of shear thinning, which indicated it was a pseudoplastic fluid. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Ionic naphthalene thermotropic copolyesters with para-linked ion-containing units

Novel ionic naphthalene thermotropic polymers (NTPs) based on wholly aromatic copolyesters were synthesized, in which ionic monomer was introduced in the form of para-linked metal hydroquinone disulfonate (HQDS). These ionic NTPs contained ionic groups of up to 4 mol%, with counterions of either monovalent K or divalent Ca, and exhibited thermotropic liquid crystallinity. The K-salts exhibited the crystalline and liquid crystalline behaviors, typically observed for a non-ionic NTP; and they developed excellent thermal and mechanical properties. Testing was made as a function of ionic content under similar processing and testing conditions. The value of glass transition temperature rose as the average molecular weight increased. Both the melting temperature, T_m, and the crystallization temperature, T_c, remained nearly constant over the composition range studied. All the K-salt ionic NTPs showed enhanced tensile properties over a non-ionic NTP. The strength increased significantly as the ionic content increased despite the decrease in the molecular weight, reflecting the dominant effect of ionic interactions over the effect of molecular weight. Enhanced tensile properties arise from enhanced interchain interactions via ionic bonds (cross-links) between highly aligned NTP chains. The incorporation of HQDS-type ‘straight’ ionic units into a NTP copolyester can provide useful information about the effect of ionic interactions on the thermal/mechanical properties of NTPs.     

Properties of Bloodmeal/Linear Low‐density Polyethylene Blends Compatibilized with Maleic Anhydride Grafted Polyethylene

Novatein thermoplastics from bloodmeal (NTP) were blended with linear low‐density polyethylene (LLDPE) using maleic anhydride grafted polyethylene (PE‐g‐MAH) as compatibilizer. The compatibilizing effect on mechanical, morphology, thermal properties, and water absorption were studied and compared with blends without compatibilizer. The amount of polyethylene added was varied between 20 and 70% in NTP with addition of 10% compatibilizer. An improvement in compatibility between NTP and LLDPE was observed across the entire composition range and the difference were more pronounced at higher NTP contents where the tensile strength of blends was maintained and never dropped below that of pure NTP. Theoretical models were compared to the results to describe mechanical properties. A finely dispersed small particles of NTP in compatibilized blends were observed using SEM. Improved compatibility has restricted chain movement resulting in slightly elevated T_g revealed by DMA. On the other hand, water absorption of the hydrophilic NTP has been decreased when blending with hydrophobic LLDPE. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1890–1897, 2013     

Friction and wear characteristics of metal sulfides and graphite‐filled PTFE composites under dry and oil‐lubricated conditions

Five kinds of polytetrafluoroethylene (PTFE)‐based composites, pure PTFE, PTFE + 30(v)% MoS₂, PTFE + 30(v)% PbS, PTFE + 30(v)% CuS, and PTFE + 30(v)% graphite (GR) composites, were first prepared. Then the friction and wear properties of these PTFE composites, sliding against GCr15‐bearing steel under both dry and liquid paraffin‐lubricated conditions, were studied by using an MHK‐500 ring‐on‐block wear tester. Finally, the worn surfaces and the transfer films of the PTFE composites formed on the surface of GCr15 bearing steel were investigated by using a scanning electron microscope (SEM) and an optical microscope, respectively. Experimental results show that filling with MoS₂, PbS, CuS, or graphite to PTFE can reduce the wear of the PTFE composites by two orders of magnitude compared to that of pure PTFE under dry friction conditions. However, the friction and wear‐reducing properties of these PTFE composites can be greatly improved by lubrication with liquid paraffin. Investigations of transfer films show that MoS₂, PbS, CuS, and graphite promote the transfer of the PTFE composites onto the surface of GCr15‐bearing steel under dry friction conditions, but the transfer of the PTFE composites onto the surface of GCr15‐bearing steel can be greatly reduced by lubrication with liquid paraffin. SEM examinations of worn surfaces show that with lubrication of liquid paraffin, the creation and development of the cracks occurred on the worn surfaces of the PTFE composites under load, which reduces the load‐supporting capacity of the PTFE composites. This would lead to the deterioration of the friction and wear properties of the PTFE composites under higher loads (>600N). © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 751–761, 1999     

Friction and wear characteristics of ceramic particle filled polytetrafluoroethylene composites under oil-lubricated conditions

Five kinds of polytetrafluoroethylene (PTFE)-based composites were prepared: PTFE, PTFE + 30 vol % SiC, PTFE + 30 vol % Si₃N₄, PTFE + 30 vol % BN, and PTFE + 30 vol % B₂O₃. The friction and wear properties of these ceramic particle filled PTFE composites sliding against GCr15 bearing steel under both dry and liquid paraffin lubricated conditions were studied by using an MHK-500 ring-block wear tester. The worn surfaces and the transfer films formed on the surface of the GCr15 bearing steel of these PTFE composites were investigated by using a scanning electron microscope (SEM)and an optical microscope, respectively. The experimental results show that the ceramic particles of SiC, Si₃N₄, BN, and B₂O₃ can greatly reduce the wear of the PTFE composites; the wear-reducing action of Si₃N₄ is the most effective, that of SiC is the next most effective, then the BN, and that of B₂O₃ is the worst. We found that B₂O₃ reduces the friction coefficient of the PTFE composite but SiC, Si₃N₄, and BN increase the friction coefficients of the PTFE composites. However, the friction and wear properties of the ceramic particle filled PTFE composites can be greatly improved by lubrication with liquid paraffin, and the friction coefficients of the PTFE composites can be decreased by 1 order of magnitude. Under lubrication of liquid paraffin the friction coefficients of these ceramic particle filled PTFE composites decrease with an increase of load, but the wear of the PTFE composites increases with a load increase. The variations of the friction coefficients with load for these ceramic particle filled PTFE composites under lubrication of liquid paraffin can be properly described by the relationship between the friction coefficient (μ) and the simplified Sommerfeld variable N/P as given here. The investigations of the frictional surfaces show that the ceramic particles SiC, Si₃N₄, BN, and B₂O₃ enhance the adhesion of the transfer films of the PTFE composites to the surface of GCr15 bearing steel, so they greatly reduce the wear of the PTFE composites. However, the transfer of the PTFE composites onto the surface of the GCr15 bearing steel can be greatly reduced by lubrication with liquid paraffin, but the transfer still takes place. Meanwhile, the interactions between the liquid paraffin and the PTFE composites, especially the absorption of liquid paraffin into the surface layers of the PTFE composites, create some cracks on the worn surfaces of the ceramic particle filled PTFE composites; the creation and development of these cracks reduces the load-supporting capacity of the PTFE composites. This leads to the deterioration of the friction and wear properties of the PTFE composites under higher loads in liquid paraffin lubrication. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2611–2619, 1999     

Two-Step Production of Oil Enriched in Conjugated Linoleic Acids and Diacylglycerol

A two-step process was used to produce diacylglycerol-enriched structured lipid that contained mainly c9,t11 and t10,c12 isomers of conjugated linoleic acids (CLA). First, a structured triacylglycerol (TAG) was synthesized by lipase-catalyzed acidolysis of corn oil with CLA. This structured triacylglycerol contained 30.4 mol% CLA with 45.5% of the CLA mostly located at sn-1,3 positions of the glycerol backbone. Then, lipase-catalyzed glycerolysis was conducted between structured triacylglycerol and glycerol to produce diacylglycerol-enriched structured lipid. The final product contained 6.8% monoacylglycerol, 31.5% diacylglycerol and 61.1% TAG after 48 h reaction. The selected chemical (fatty acid composition, the content of mono-, di-, and triacylglycerol in the reaction product) and physical properties (melting profile) were determined by hihg-performance liquid chromatography (HPLC), gas chromatography (GC), and differential scanning calorimetry (DSC).     

New Process for the Acid-Catalyzed Conversion of Cellulosic Biomass (AC3B) into Alkyl Levulinates and Other Esters Using a Unique One-Pot System of Reaction and Product Extraction

Abstract  

A one-pot system used for the chemical/catalytic conversion of cellulosic biomass, and the product extraction was developed. The latter phase was carried out by a distillation technique that combines a temperature-programmed heating with a vacuum level-programmed evacuation (technique of mild vacuum-assisted distillation, MVAD). No environmentally harmful solvent was used: only a high boiling paraffin (n-dodecane) was used to help distil the heavy products. The obtained liquid fractions (light and heavy fractions) could be used, after drying and removal of unused alcohol, for blending into gasoline or diesel/biodiesel. Two different conversion procedures were used: ethanolysis (direct acid-catalyzed conversion in ethanol medium) and a sequential procedure, the latter consisting of the “acid hydrolysis followed by the esterification of resulting acids with ethanol”. By using wood residues as raw material, the yields in ethyl levulinate and other by-products—with the only exception of diethyl ether (DEE), were quite similar for both procedures. The incorporation of some H-USY zeolite could significantly decrease the yield of DEE in the ethanolysis procedure. Reported results obtained with some other biomass feedstocks (particularly, switch grass) showed a good relationship between the product levulinate yield and the cellulose content of the raw material.     

Efficient preparation and characterization of paraffin-based microcapsules by emulsion polymerization

Microencapsulated phase-change materials (MEPCMs) with paraffin as the core and poly(methyl methacrylate) (PMMA) and PMMA copolymers as the shell were prepared by emulsion polymerization using redox initiators at low temperatures. Fourier transform infrared spectroscopy was used to characterize the chemical composition of MEPCMs. The thermal properties and thermal stabilities of MEPCMs were tested by differential scanning calorimetry and thermogravimetric analysis. The morphologies and sizes of the microcapsules were investigated by scanning electron microscopy and particle size distribution analysis. The results indicated that the yield of microcapsules is as high as 96.2%, and the encapsulation efficiency of paraffin is nearly 100% when the paraffin content in MEPCM is 70%. The MEPCMs have good stability: the leakage ratios of MEPCMs can be less than 1% after 50 heating–cooling cycles. Therefore, the microencapsulation of paraffin using redox initiators has good production and application prospects. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47552.     

Factors affecting analytical values of beeswax and detection of adulteration

Various factors that could affect analytical values for beeswax, and so also detection of adulteration, have been investigated. Ester value determination was checked using synthetic monoesters. Gas liquid chromatographic analysis of overheated wax confirmed that free acids decreased on heating and also showed loss of unsaturated hydrocarbons and of monoesters. The saponification cloud point detected as little as 1% of a paraffin mp 83 C (chain length C₂₀–C₆₀) but only 6% or more of a paraffin mp 53 C (chain length C₂₀–C₃₅). Gas liquid chromatographic analysis of the hydrocarbon fraction of waxes containing these paraffins detected 1% of either paraffin, but only the low melting paraffin was estimated accurately. The presence of 2.5% of carnauba wax in beeswax was detected and estimated by gas liquid chromatography. Issued as NRCC No. 13173.     

Preparation of oligochitosan via In situ enzymatic hydrolysis of chitosan by amylase in [Gly]BF4 ionic liquid/water homogeneous system

The preparation of oligochitosan with excellent performance via in situ enzymatic hydrolysis of chitosan by amylase in ionic liquid system is reported. It has been found that [Gly]BF₄ ionic liquid leads to the good solubility and assistant degradation for chitosan, as well as good biocompatibility for amylase. In the homogeneous system that contained 1.0 g chitosan (degree of deacetylation = 88.5%) and 99.0 g 2 wt % [Gly]BF₄ aqueous solution, oligochitosan with 2200 viscosity‐average molecular weight has been obtained after 0.12 g amylase being used for 3 h at 50°C and pH 5.0. This result is superior to that conducted in acetic acid system. Moreover, [Gly]BF₄ can be easily separated from the product and reused with only slight performance loss (oligochitosan product with 2700 viscosity‐average molecular weight has been obtained after [Gly]BF₄ being reused for five times). In addition, the mechanism for enzymatic hydrolysis of chitosan in [Gly]BF₄ ionic liquid has been described. The research on the moisture‐absorption, ‐retention, and antibacterial activity of oligochitosan product shows that the smaller molecular weight would bring the better moisture‐absorption and antibacterial properties. The oligochitosan product with 2200 viscosity‐average molecular weight exhibits preferable antibacterial properties to S. aureus and E. coli. At the same time, the moisture‐absorption and ‐retention capacity of the above product can reach 32% (relative humidity (RH) = 43%), 62% (RH = 81%), and 150% (RH = 43%), 35% (dry silica gel) respectively. The enzymatic preparation of oligochitosan through [Gly]BF₄ ionic liquid/water homogeneous system can be an efficient and environment‐friendly method for academics and industry. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41152.     

Friction and wear characteristics of fiber- and whisker-reinforced PTFE composites under oil lubricated conditions

Four kinds of polytetrafluoroethylene (PTFE)-based composites, such as pure PTFE, PTFE + 30(vol.)% carbon fiber, PTFE + 30(vol.)% glass fiber, and PTFE + 30(vol.)% K₂Ti₆O₁₃ whisker composite, were prepared. The friction and wear properties of these fiber- and whisker-reinforced PTFE composites sliding against GCr15-bearing steel (SAE52100 steel) under both dry and liquid paraffin lubricated conditions were studied by using an MHK-500 ring-block wear tester (Timken wear tester). Then the worn surfaces of these PTFE composites and the transfer films formed on the surface of GCr15-bearing steel were investigated by using a Scanning Electron Microscope (SEM) and an Optical Microscope, respectively. Experimental results show that the friction and wear properties of the PTFE composites reinforced with carbon fiber, glass fiber, and a K₂Ti₆O₁₃ whisker can be greatly improved by lubrication with liquid paraffin, and the friction coefficients of these PTFE composites can be decreased by one order of magnitude compared to those under dry friction conditions. Meanwhile, the wear of the fiber- and whisker-reinforced PTFE composites in liquid paraffin lubrication increases with the increase of load, but the friction coefficients of these PTFE composites first decrease with the increase of load, and then increase with the increase of load. The variations of friction coefficients with load for these PTFE composites in liquid paraffin lubrication can be described properly by the Stribeck's curve as given in this article. However, when the load increases to the load limits of the PTFE composites, their friction and wear increase sharply. SEM and optical microscope investigations show that the interactions between liquid paraffin and the PTFE composites, especially the absorption of liquid paraffin into the surface layers of the PTFE composites, create some obvious cracks on the worn surfaces of the PTFE composites. The creation and the development of the cracks reduce the load-carrying capacity of the PTFE composites, and therefore lead to the increase of the friction and wear of the PTFE composites under higher loads. Meanwhile, the transfer of the fiber- and whisker-reinforced PTFE composites onto the counterfaces can be greatly reduced by lubrication with liquid paraffin, but the transfer still takes place. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1393–1402, 1998     

Friction and wear characteristics of PTFE composites filled with metal oxides under lubrication by oil

Four kinds of polytetrafluoroethylene(PTFE)-based composites, such as pure PTFE, PTFE+30%(v)PbO, PTFE+30%(v)Pb₃O₄, and PTFE+30%(v)Cu₂O composite, were prepared. The friction and wear properties of these metal oxides filled PTFE composites sliding against GCr15 bearing steel in both dry and lubricated conditions were studied by using an MHK-500 ring-block wear tester. Then the worn surfaces of these PTFE composites and the transfer films of these PTFE composites formed on the surface of GCr15 bearing steel were examined by using a Scanning Electron Microscope (SEM) and an Optical Microscope, respectively. Experimental results show that the friction and wear properties of these metal oxide-filled PTFE composites can be greatly improved by liquid paraffin lubrication, and the friction coefficients can be decreased by one order of magnitude. Meanwhile, the interactions between liquid paraffin and metal oxide-filled PTFE composites, especially the absorption of liquid paraffin into the surface layers of these PTFE composites, reduce the mechanical strength and the load-carrying capacity of these metal oxide-filled PTFE composites. This leads to the deterioration of the friction and wear properties of these PTFE composites. Investigations of the frictional surfaces show that Pb₃O₄, Cu₂O, and PbO enhance the adhesion of the transfer films to the surface of GCr15-bearing steel, and thus promote the transfer of the PTFE composites onto the surface of GCr15-bearing steel. Therefore, they greatly reduce the wear of the PTFE composites. However, the transfer of these PTFE composites onto the counterfaces can be greatly reduced by lubrication with liquid paraffin. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 85–93, 1997     

Control of swelling in liquid emulsion membranes employed for lactic acid separation

Control of the swelling of two different liquid emulsion membrane systems for separation of lactic acid was examined. The major disadvantages of swelling are dilution of the separated product and emulsion breakage. Several additives including liquid paraffin, cyclohexanone and n-decanol were investigated with respect to both emulsion swelling and lactic acid separation rate. If swelling is a function of surfactant concentration, the swelling increases with the quantity of the hydrophilic part in the surfactant. Therefore, a surfactant with a low hydrophilic/lipophilic balance (HLB) value should be used to reduce the swelling. The use of Span 85 (HLB = 1·8) as co-surfactant achieved the objective in the case of a tri-n-octylamine/Span 80 system.     

Friction and wear behavior of PTFE composites filled with rare earth compounds under oil‐lubricated conditions

Polytetrafluoroethylene (PTFE)‐based composites, filled with CeO₂, CeF₃, and La₂O₃ in volume contents of 5, 10, 15, 20, and 30%, were prepared. Then, the friction and wear behavior of these PTFE composites sliding against GCr15 bearing steel under both dry and liquid paraffin‐lubricated conditions was evaluated using an MHK‐500 ring‐on‐block wear tester. Finally, the worn surfaces and the transfer films of these PTFE composites were investigated using a scanning electron microscope (SEM) and an optical microscope. Experimental results showed that filling CeO₂, CeF₃, and La₂O₃ into PTFE can reduce the wear of the PTFE composites by 1–2 orders of magnitude. When the content of CeO₂ in PTFE is 15%, the friction and wear properties of the CeO₂‐filled PTFE composite are the best. Meanwhile, when the content of La₂O₃ in PTFE is between 15 and 20%, the PTFE composite filled with La₂O₃ exhibits excellent friction and wear‐reducing properties. However, the friction coefficient of the CeF₃‐filled PTFE composite increases but its wear decreases with increase in the content of CeF₃ from 5 to 30%. The friction and wear‐reducing properties of CeO₂‐, CeF₃‐, and La₂O₃‐filled PTFE composites can be greatly improved by lubrication with liquid paraffin, but the limit loads of the PTFE composites decrease with increase in the content of CeO₂, CeF₃, and La₂O₃ in PTFE (from 5 to 30%) under the same conditions. Investigations of worn surfaces show that the interaction between liquid paraffin and the CeO₂‐, CeF₃‐, and La₂O₃‐filled PTFE composites, especially the absorption of liquid paraffin into the microdefects of the PTFE composites, creates some cracks on the worn surfaces of the PTFE composites and that the creation and development of the cracks reduces the mechanical strength and the load‐supporting capacity of the PTFE composites. However, with increase of the content of CeO₂, CeF₃, and La₂O₃ in the PTFE, the microdefects in the PTFE composites also increase, which would lead to increase in the number of the cracks on the worn surfaces of the PTFE composites under load and, so, in turn, lead to the reduction of the limit loads of the CeO₂‐, CeF₃‐, and La₂O₃‐filled PTFE composites under lubrication with liquid paraffin. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 78: 797–805, 1999     

Effects of lubricating‐oil additives on the friction and wear properties of polymers and their composites sliding against steel under oil‐lubricated conditions

The effects of lubricating‐oil additive zinc dialkyldithiophosphate (ZDDP) on the friction and wear properties of polymers and their composites sliding against GCr15 bearing steel were studied by using an MHK‐500 ring‐on‐block wear tester (Timken wear tester). Then the frictional surfaces of the friction pairs were examined by using electron probe microanalysis (EPMA). Experimental results show that the ZDDP contained in liquid paraffin has little effect on the friction coefficients of the polyimide (PI) or polyamide 66 (PA66) against GCr15 bearing steel friction pairs compared with that under the lubrication of liquid paraffin, but it slightly reduces the friction coefficients of polytetrafluoroethylene (PTFE) or its composites against GCr15 bearing steel friction pairs. Under lubrication of liquid paraffin containing 2 wt % ZDDP, the ZDDP film absorbed on the frictional surfaces of the PTFE composites–GCr15 bearing steel friction pairs exhibits obvious antiwear properties; it greatly reduces the wear of pure PTFE and the PTFE composites filled with Pb, PbO, and MoS₂; and the wear of the PTFE composites can be reduced by one order of magnitude compared with that under lubrication of pure liquid paraffin. Meanwhile, the inorganic fillers Pb, PbO, and MoS₂ contained in PTFE have little effect on the absorption of ZDDP to the frictional surfaces, so they have little effect on the friction coefficients of the PTFE composites–GCr15 bearing steel friction pairs under the lubrication of liquid paraffin containing 2 wt % ZDDP. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1240–1247, 2000     

Effect of acrylonitrile content of styrene-co-acrylonitrile (SAN) on morphology and electrooptical properties of polymer/liquid crystal composite films

Effects of copolymer composition on morphology and electrooptical properties of polymer/liquid crystal (LC) (40/60 w/w) composite films were studied with styrene-co-acrylonitrile (SAN) of varying acrylonitrile (AN) content (6.3–35 wt %) and a cyanobiphenyl-type liquid crystal (E8). The dimension of the LC domain in the composite film decreased with increase of AN content of SAN up to 30 and increased at 35 wt %. The contact angle of the film with an LC drop showed a similar trend; however, its minimum was obtained at 24% AN. Threshold voltage (V_th) and rise time (τ_R) increased, and decay time (τ_D) decreased with AN content up to 30%, and the tendency is reversed at 35%. The results were interpreted in terms of, possibly, a solubility parameter matching between SAN and LC. © 1993 John Wiley & Sons, Inc.     

Study of lactic acid extraction with higher molecular weight aliphatic amines

Lactic acid extraction was studied with two extractants, trioctyl amine (TOA) and Aliquat 336, in three diluents (methylisobutyl ketone (MIBK), octanol and paraffin liquid). The effects of organic phase extractant concentration and aqueous phase pH on the extraction process were examined. Among the extractants, TOA was found to be a better extractant than Aliquat 336 in all the diluents. In experiments with 50% (v/v) TOA in methylisobutyl ketone, 79% lactic acid could be extracted (initial lactic acid concentration 86·96 g dm⁻³). MIBK had a profound effect on the extraction behaviour of TOA in comparison with octanol and paraffin liquid while none of the diluents affected the extraction with Aliquat 336. The extraction of lactic acid was favoured at low pH. The toxicities of TOA and the diluents to Lactobacillus rhamnosus NRRL B445 were also studied. While TOA was found to be highly toxic at the molecular and the phase level, the paraffin liquid was totally non-toxic. The extraction of glucose and yeast extract by TOA and the diluents used was found to be low, which thus enables the selective extraction of lactic acid. © 1998 SCI     

Physicochemical Properties of Phytopharmaceutical Preparations as Affected by Drying Methods and Carriers

This article reports a study of the effects of the drying methods and drying carriers on system performance and physicochemical properties of spray- and spouted bed–dried phytopharmaceutical preparations from Bidens pilosa L. Colloidal silicon dioxide, β-cyclodextrin, maltodextrin dextrose equivalent (DE) 10, and microcrystalline cellulose were used as drying carriers. The dried product was characterized by the particle size and morphology, total flavonoid content, solubility, flowability, and water activity. High-performance liquid chromatography (HPLC) was used to detect four marker compounds previously reported for this plant. Spray and spouted bed drying systems were compared through energetic efficiency, product recovery, elutriation, and product accumulation. The crystalline state of the powders was assessed by X-ray diffraction. Results showed high degradation rates for total flavonoid content and marker compounds during spouted bed drying. Depending on the drying carrier added to extractive solutions, different degrees of protection from degradation were conferred, and the physical characteristics of the product were changed accordingly. The lowest flavonoid degradation (8.6%) and the higher concentration of marker compounds were obtained using β-cyclodextrin as the drying carrier. Particle size was higher when a blend of Aerosil (Evonik Degussa, Hanau, Germany) and cellulose was employed as the drying carrier. A maximum product recovery of 86.9% was achieved by spray drying and 72.9% by spouted bed drying with the Aerosil : cellulose composition.     

Polycyclic aromatic hydrocarbon emissions of non-road diesel engine treated with non-thermal plasma technology

Non-road diesel engines are important polycyclic aromatic hydrocarbon (PAH) sources in the environment due to their high emission concentration compared to on-road diesel engines. Particle- and gas-phase PAH concentrations of a non-road diesel engine were investigated. Non-thermal plasma (NTP) as an effective after-treatment technology was used to reduce PAH emissions. The results showed that particle-phase PAH concentrations were 329.7 µg/m³, 3,206.7 µg/m³, and 1,185.7 µg/m³ without the action of NTP at three different engine loads respectively. Relatively low concentrations were measured for gas-phase PAHs. Excellent linearity was shown for particle-phase with total PAH concentrations both with, and without, NTP. The gas-phase PAH concentrations linearly increased with engine load without NTP. The five most abundant compounds of PAHs were among low molecular weight (LMW) and medium molecular weight (MMW) compounds. Total PAH cleaning efficiency was beyond 50% when treated with NTP at the three different engine loads. We hypothesized that naphthalene (Nap) concentrations increased greatly at 60% and 80% engine loads because it was produced within the plasma zone by decomposition of high molecular weight (HMW) PAHs. The PAHs content of particulate matter (PM) aggregation at 60% load was approximately three times higher than at 40% and 80% loads. High correlation values were observed for MMW PAHs with total PAH concentrations. Correlations of PAH concentration reduction could be important to clarify the PAH reduction mechanism with NTP technology.