Non-thermal Method Research Articles

Pathomorphologic characteristics of venous vessels after the application of different methods of endovascular eliminating of venous reflux - experimental study

Varicose veins have been the subject of a recent technologies of nontumescent treatment that outline the safety and effectiveness questions concerning proposed obliteration methods. The goal of this study is to analyze changes in the venous wall structure appearing as a result of using thermal tumescent and nonthermal nontumescent methods in compare. Methods: microscopic investigation of vein specimens of adult sheep (n=9) performed on 1, 7 and 100 day after procedure to determine the grade of damage and inflammation. Results: On the 1st and 7th days after the use of endovenous laser, endothelial destruction was 100%, with total depth damage of vein wall and total destruction of the elastic carcass, also traces of carbonization on the first and vaporization on the seventh day have been seen. In a result of the use of nonthermal method, there was a residual endothelium up to 30%; with the use of cyanoacrylate glue - up to 10%. In the long-term period of observation, glue masses undergo a sewage process and is preserved as separate lumps, there is an abundance of multicore macrophages with fragmented glue in the cytoplasm. Conclusion: the results allow us to consider nonthermal nontumescent methods as a possible alternative to thermal methods available in clinical practice.

Utilization of rice husk (Oryza sativa) for amorphous biosilica (SiO2) production as a bacterial attachment

Rice husk as a by-product of the rice milling process has not been utilized optimally. The yield of rice husk waste continues to increase from year to year, considering that Indonesia is the third largest rice producer in the world. Rice husk has a fairly large silica content; therefore, rice husk is widely used as an alternative source of silica. The purpose of this study is to synthesize silica from rice husk and analyse its characteristics. The research method used in silica isolation was carried out by non-thermal and thermal methods. Non-thermal method for removal of inorganic compounds and hydrolysis of organic compounds by acidic solutions (HCl), while the thermal method is carried out by burning rice husks at a temperature of 500 °C to produce rice husk ash. The resulting rice husk ash was processed by the sol-gel method. The resulting silica was determined of its morphology by Scanning Electron Microscopy (SEM), composition, and structure with Fourier Transform Infrared Spectroscopy (FT-IR). The results obtained in this study were white silica with a yield of 84.782%. Biosilica produced is then mixed with certain bacteria, either Serratia sp or Bacilus pumilus. Then, the attachment of bacteria was evaluated by using SEM (Scanning Electron Microscopy).

Irreversible electroporation after induction chemotherapy versus chemotherapy alone for patients with locally advanced pancreatic cancer: A propensity score matching analysis

BackgroundLocally advanced pancreatic cancer (LAPC) is a devastating disease and irreversible electroporation (IRE) is a non-thermal ablation method that is especially suitable for the treatment of LAPC. This study aimed to compare the long-term survival of LAPC patients after induction chemotherapy followed by IRE and chemotherapy alone. MethodsFrom August 2015 to August 2017, a total of 132 patients with LAPC were identified. The oncological outcomes of these two treatments were analyzed by propensity score matching (PSM) analysis. ResultsBefore PSM analysis, patients with LAPC had better overall survival (OS) and progression-free survival (PFS) after induction chemotherapy followed by IRE than those who received chemotherapy alone (2-year OS rates, 57.9% vs 19.8%, P < 0.001; 2-year PFS rates, 31.4% vs 9.3%, P < 0.001). The baseline clinicopathological factors were balanced between the 2 groups through PSM analysis. Even after PSM, the OS and PFS rates of patients after induction chemotherapy followed by IRE treatment were superior to those of patients who received chemotherapy treatment alone (2-year OS rates, 57.9% vs 18.1%, P < 0.001; 2-year PFS rates, 31.4% vs 7.1%, P < 0.001). Multivariate Cox regression analysis indicated that chemotherapy plus IRE was a significant prognostic factor for both OS and PFS in patients of both the whole cohort and the matched cohort. ConclusionsInduction chemotherapy followed by IRE provided better OS and PFS than chemotherapy alone for patients with LAPC. This combination method may be a more suitable treatment for patients with LAPC.

Removal of Dry-Etch-Induced Surface Layer Damage from p-GaN by Photoelectrochemical Etching

A non-thermal method for removal of surface damage created by dry etching has previously been documented or n-GaN, but no such effort has been reported for p-GaN. In this study, Ga-polar p-GaN films were subjected to inductively coupled plasma reactive ion etching, creating damage near the surface and causing an inversion of the carrier type and concentration from + 5.5 × 1012 cm−2 to − 8.8 × 1010 cm−2, as measured by Hall effect. An application of the carrier-type-selective photoelectrochemical (PEC) etching technique using a KOH and K2S2O8 etch chemistry is employed in order to remove etch-face damage and recover the underlying p-GaN. We show the type selectivity of the PEC etching technique, demonstrating electroless etching of n-GaN while no interaction of the same etch chemistry with p-GaN is observed. Further, surface analysis shows that the PEC etch removes a surface layer from dry-etched p-GaN and increases its roughness substantially, from 0.64 nm to 71 nm RMS.

Computer-aided Box–Behnken outlook towards optimization of extraction of lawsone from mehendi leaves

Pharmacognosy Magazine,2020,16,68,39-46.DOI:10.4103/pm.pm_345_19Published:March 2020Type:Original ArticleAuthors:Lubna Abidin, Mohd Mujeeb, Mohd Aqil, Abul Kalam Najmi, and Aftab Ahmad Author(s) affiliations:Lubna Abidin1, Mohd Mujeeb1, Mohd Aqil2, Abul Kalam Najmi3, Aftab Ahmad4 1 Phytomedicine Laboratory, Department of Pharmacognosy and Phytochemistry, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India 2 Department of Pharmaceutics, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India 3 Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India 4 Department of Health Information Technology, Jeddah Community College, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia Abstract:Background: Since ages lawsone, an orange-colored dye from leaves of Lawsonia inermis is being used by women for self-adornment and is also used in textile industries for dyeing reasons. Objective: Comparing traditional and modern extraction modes for extraction of lawsone from L. inermis leaves and simultaneous use of response surface methodology for optimizing its extraction procedure. Materials and Methods: Design-Expert software was exploited for optimization task. Quantification of lawsone in different extracts was done by high-performance liquid chromatography using aqueous acetic acid and methanol in the mobile phase. Results: Ultrasound-assisted extraction stood out to be a supreme technique among all. Moreover, of all solvents (ethylene glycol, dimethylformamide, and methanol) examined methanol stood out to be the most effective solvent for lawsone extraction. By the inverse matrix of the regression model and point prediction, optimal conditions for lawsone extraction were laid down as - extraction temperature - 50.24°C, extraction time - 15.70 min, liquor to material ratio - 24.16 mL/g, and methanol concentration - 75.15%v/v which yielded 17.129 g of lawsone. Under similar conditions (extraction temperature - 50°C, extraction time - 16 min, liquor to material ratio - 24 mL/g, and methanol concentration - 75%v/v), 16.98 g of lawsone was yielded which was close to predicted value. Conclusion: We conclude that a non-thermal method proved to a supreme technique for lawsone extraction which has an additional benefit which of avoiding thermal degradation of compound. Furthermore, by model fitting and analysis of regression coefficients, it was confirmed that all the factors studied significantly affected lawsone yield. Keywords:Box–Behnken design, Lawsone, Lawsonia inermis, naphthoquinone, response surface methodology, UltrasonicationView:PDF (2.19 MB)

Influence of Mode of Power Source on the Mechanical Properties of Vibratory Weld Joints

Welding plays a major role in modern technology. During welding, a portion of the specimen is subjected to heating. Because of different heating and cooling cycles of the specimen, residual stresses induced in the specimen i.e., mechanical properties gets reduced. To enhance the mechanical properties there are different techniques are available i.e., thermal and non-thermal methods. Vibratory welding is the one of the non-thermal method; mechanical properties of steel specimens are analyzed under with and without vibrations under different power source condition. In this paper input parameters which are considered is straight polarity, reverse polarity and alternate current. Tensile and hardness property of the steel specimen are analyzed and compared with the without vibratory condition.

Synergistic Collaboration between a Viscosity Reducer and a Surfactant for in Situ Emulsion Formation to Enhance Heavy-Oil Recovery

In situ emulsion formation is an effective nonthermal method to improve conventional heavy-oil recovery. In this paper, a newly designed viscosity reducer (TPVR7) and a high-performance surfactant ...

High-Hydrostatic-Pressure (HHP) Processing Technology as a Novel Control Method for Listeria monocytogenes Occurrence in Mediterranean-Style Dry-Fermented Sausages.

Although conventional microbial control techniques are currently employed and largely successful, their major drawbacks are related to their effects on quality of processed food. In recent years, there has been a growing demand for high-quality foods that are microbially safe and retain most of their natural freshness. Therefore, several modern and innovative methods of microbial control in food processing have been developed. High-hydrostatic-pressure (HHP) processing technology has been mainly used to enhance the food safety of ready-to-eat (RTE) products as a new pre-/post-packaging, non-thermal purification method in the meat industry. Listeria monocytogenes is a pertinent target for microbiological safety and shelf-life; due to its capacity to multiply in a broad range of food environments, is extremely complicated to prevent in fermented-sausage-producing plants. The frequent detection of L. monocytogenes in final products emphasizes the necessity for the producers of fermented sausages to correctly overcome the hurdles of the technological process and to prevent the presence of L. monocytogenes by applying novel control techniques. This review discusses a collection of recent studies describing pressure-induced elimination of L. monocytogenes in fermented sausages produced in the Mediterranean area.

Inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium in edible bird's nest by low-energy X-ray irradiation

Continuing polychromatic low-energy X-ray possesses a high linear energy transfer (LET) effect and correspondingly a high relative biological effect (RBE), which makes it a promising non-thermal processing method for food preservation. This study evaluated the efficacy of low-energy X-ray with cut-off energy of 150 KeV to inactivate two of the most prevalent foodborne pathogens in dry edible bird's nest (EBN). The X-ray irradiation at 350 and 400 Gy decreased E. coli O157:H7 and S. Typhimurium from 6.35 ± 0.56 and 5.84 ± 0.67 log CFU/g, respectively, to undetectable level. The low-energy X-ray irradiation yielded the tR1 value of 37.6 ± 6.9 and the D10 value of 83.3 ± 7.0 Gy for E. coli O157:H7 and S. Typhimurium, respectively, which indicates that S. Typhimurium exhibited more resistant to low-energy X-ray irradiation than E. coli O157:H7. Based on dose distribution in 10 sacked pieces of EBN, two-sided irradiation can assure the uniformity of processing. As for the quality of processed EBN, while the irradiation increased the yellowness of EBN (p < 0.05), no sulfur-containing volatile compounds were detected in the irradiated samples. These results show that low-energy X-ray can serve as an effective method to inactivate foodborne pathogens in dry EBN.

Cross-linked chitosan microparticles preparation by modified three fluid nozzle spray drying approach

Owing to chitosan’s incredible biocompatibility and biodegradability, bioactive molecules loaded delivery systems based on this polymer have been widely studied for improved health benefits. In the present work, quercetin and ferulic acid encapsulated core-shell structure chitosan microparticles crosslinked with tripolyphosphate and sodium alginate have been fabricated using unique three fluid nozzle (3-FN) spray drying technique. Fluorescent molecules incorporated into the microparticles aided observation of core-shell structure formation. Compatibility studies, physicochemical properties, and free radical scavenging activity of microparticles were assessed. Microscopic analysis revealed core-shell structured, spherical shaped microparticles. Thermal and non-thermal method of evaluation confirmed the crosslinking, compatibility and encapsulation of bioactive molecules with the carrier materials. The dual bioactive molecules-loaded microparticles exhibited sustained release pattern (85–88%) for 24 h and had better free radical scavenging potency. Such cross-linked core-shell structured microparticle is a promising dual delivery system for encapsulating bioactive molecules with synergistic antioxidant activity.

Molecular dynamics simulation of high-pressure CO2 pasteurization reveals the interfacial denaturation of proteins at CO2/water interface

While mirobial and enzyme inactivation by CO2 is a promising non-thermal method for cold pasteurization of liquid foods, the poor understanding of the underlying molecular mechanism limits the development of this procedure. The complexity of the process along with the high-pressure conditions have disabled the experimental techniques to establish microstructural information for this phenomenon. In this work, molecular dynamics simulation method was used to find microscopic insights about this system. Myoglobin protein and lysozyme enzyme have applied as models in the simulations. It was found that CO2 and water make a distinct biphasic system in the experimental pressures of pasteurization process. Although many hypothesizes have attributed the enzyme inactivation to the solubilized CO2 molecules in the aqueous phase, we have shown that enzymes can be inactivated by an “interfacial denaturation” mechanism. Results show that the protein migrates from pure aqueous phase to the CO2/water interface and becomes denatured there. The molecular mechanism includes releasing the hydrophobic cores to the CO2 phase and escaping of the hydrophilic surface residues to the aqueous phase. These two phenomena denature the protein to a flat and extended conformation. Moreover, chemotrypsin inhibitor 2 protein was used to obtain the effect of distance from interface in the denaturation process. It was found that the distance from interface is critical in both performance and rate of the denaturation. Our simulations not only shed some lights on the molecular mechanism of CO2 pasteurization methods, but it can also be a basic computational model for further technological design and development.

Extra-Virgin Olive Oil Extracted Using Pulsed Electric Field Technology: Cultivar Impact on Oil Yield and Quality.

The main operators of the olive oil sector are continuously involved in the development of the olive oil mechanical extraction process with the common aim of increasing both the quality and the oil extraction yield coupled with the potential enhancement of the working efficiency of the olive mill. The pulsed electric field (PEF) is a recently studied technological innovation for the improvement of olive oil extraction technology. The impact of the PEF on the diffusion of oil and microconstituents, determined by the disruption effects on olive cell tissues carried out by the non-thermal method, was evaluated. A PEF can increase the permeability and breaking of the cell membranes with a consequent positive result on oil extractability and quality, mainly related to the compounds involved in the health and sensory properties of extra virgin olive oil. The PEF was tested on three Italian olive cultivars (Carolea, Coratina, and Ottobratica). The results showed a positive impact of the new technology on the oil yield, with an increase ranging from 2.3 to 6%, and on the concentration of hydrophilic phenols, with an increase ranging from 3.2 to 14.3%, with respect to the control tests. The data of the main compounds related to the health and sensory notes also showed high variability as a consequence of the genetic origins of the olive cultivars.

Inactivation mechanism of E. coli O157:H7 under ultrasonic sterilization.

Ultrasonic sterilization (US), as a promising non-thermal sterilization method, exhibits unique superiorities than traditional sterilization methods. In this study, the inactivation mechanism of E. coli O157:H7 under US was investigated in cucumber and bitter gourd vegetable juices. Results revealed that the US treatment showed good antibacterial ability in countering E. coli O157:H7. Through determinations of conductivity and β-galactosidase activity, significant augmentation in membrane permeability of the bacteria was confirmed after the US treatment. The morphologies of the US treated E. coli O157:H7 demonstrated that the integrity of the cell membrane was disrupted by US treatment. SDS-PAGE and LSCM data further proved the disruptive action of US, leading to the leakage of proteins and DNA through the breakage on cell membrane. The decrease of metabolic-related enzyme activity was verified through investigation of bacterial metabolism. The antibacterial mechanism analysis indicated that the US can generate free radicals which resulted in the rise of intracellular oxidative stress, attenuation of energy metabolism and inhibition of hexose monophosphate pathway. As the application verification, the US treatment can cause the deprivation of E. coli O157:H7 cell viability in vegetable juices without obvious impact on the sensory quality.

Mechanochemical stabilization of heavy metals in fly ash with additives

Mechanochemistry, as a non-thermal method showing remarkable degradation for persistent organic pollutants, is extended to stabilize the heavy metals in municipal solid waste incineration (MSWI) fly ash in the present study. The leaching suppression of heavy metals (i.e., Zn, Pb, Cu, Cr, Cd, and Ni) facilitated by five additives during mechanochemical (MC) treatment is systematically investigated, identifying that almost all heavy metals are effectively suppressed with the assistance of either CaO or Ca3(PO4)2. The pH-dependent leaching test further reveals the superiority of Ca3(PO4)2 over CaO for heavy metals stabilization. Moreover, the evolution of heavy metal speciations analysed via an optimized sequential extraction procedure shows that MC treatment with Ca3(PO4)2 significantly reduces the water- and acid-soluble fraction with high mobility from 56.8, 1.39, 12.3, 8.46, 1.13, and 29.5% to 4.96, 0.17, 0.14, 7.36, 0.12, and 0.22%, respectively for Cd, Cr, Cu, Ni, Pb, and Zn. The risk assessment indicates remarkable detoxification of fly ash in terms of heavy metals after MC treatment: the Nemerow pollution index is dramatically decreased from 9.35 (far above 3.0- the threshold of seriously polluted domain) to 0.71 (slightly over 0.7- the threshold of safety domain). Finally, a hypothetical mechanism according with results in this study for MC stabilization of heavy metals in fly ash is proposed as: the conversion of heavy metal compounds from mobile to immobile form through reaction with additives after activated by mechanical energy.

A dose-response study of a novel method of selective tissue modification of cellular structures in the skin with nanosecond pulsed electric fields.

Background and ObjectivesThis study describes the effects of nanosecond pulsed electric fields (nsPEF) on the epidermis and dermis of normal skin scheduled for excision in a subsequent abdominoplasty. NsPEF therapy applies nanosecond pulses of electrical energy to induce regulated cell death (RCD) in cellular structures, with negligible thermal effects. Prior pre‐clinical studies using nsPEF technology have demonstrated the ability to stimulate a lasting immune response in animal tumor models, including melanoma. This first‐in‐human‐use of nsPEF treatment in a controlled study to evaluate the dose‐response effects on normal skin and subcutaneous structures is intended to establish a safe dose range of energies prior to use in clinical applications using nsPEF for non‐thermal tissue modification.Study Design/Materials and MethodsSeven subjects with healthy tissue planned for abdominoplasty excision were enrolled. Five subjects were evaluated in a longitudinal, 60‐day study of effects with doses of six nsPEF energy levels. A total of 30 squares of spot sizes 25mm2 or less within the planned excision area were treated and then evaluated at 1 day, 5 days, 15 days, 30 days, and 60 days prior to surgery. Photographs were taken over time of each treated area and assessed by three independent and blinded dermatologists for erythema, flaking and crusting using a 5‐point scale (0 = low, 4 = high). Punch biopsies of surgically removed tissue were processed and evaluated for tissue changes using hematoxylin and eosin, trichome, caspase‐3, microphthalmia transcription factor, and elastin stains and evaluated by a dermatopathologist. The skin of two subjects received additional treatments at 2 and 4 hours post‐nsPEF and was evaluated in a similar manner.ResultsMost energy settings exhibited delayed epidermal loss followed by re‐epithelization by day 15 and a normal course of healing. Histologic analysis identified the appearance of activated caspase‐3 at two and four hours after nsPEF treatment, but not at later time points. At the 1‐day time point, a nucleolysis effect was observed in epidermal cells, as evidenced by the lack of nuclear staining while the epidermal plasma membranes were still intact. Cellular structures within the treatment zone such as melanocytes, sebaceous glands, and hair follicles were damaged while acellular structures such as elastic fibers and collagen were largely unaffected except for TL6 which showed signs of dermal damage. Melanocytes reappeared at levels comparable with untreated controls within 1 month of nsPEF treatment.ConclusionsThe selective effect of nsPEF treatment on cellular structures in the epidermal and dermal layers suggests that this non‐thermal mechanism for targeting cellular structures does not affect the integrity of dermal tissue within a range of energy levels. The specificity of effects and a favorable healing response makes nsPEF ideal for treating cellular targets in the epidermal or dermal layers of the skin, including treatment of benign and malignant lesions. NsPEF skin treatments provide a promising, non‐thermal method for treating skin conditions and removing epidermal lesions. © 2019 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Antimicrobial mechanism of pulsed light for the control of Escherichia coli O157:H7 and its application in carrot juice

As a non-thermal sterilization method, pulsed light (PL) has been widely applied in food industries to control the microbial contamination, however little is known about the antimicrobial mechanism of PL. This study deeply investigated the antimicrobial mechanism of PL against Escherichia coli O157:H7 (E. coli O157:H7). The changes of morphology, endoenzyme, entocyte, respiratory metabolism and DNA of E. coli O157:H7 after PL treatment were emphatically studied. TEM and SEM results exhibited that cell integrity was destroyed heavily after PL treatment. Entocyte including proteins, ATP and DNA were reduced remarkably for PL-treated samples. In addition, the activity of ATPase, β-galactosidase, alkaline phosphatase, topoisomerase, as well as the metabolism were inhibited for E. coli O157:H7 with PL treatment. The electron spin resonance spectrum validated the production of hydroxyl radical by PL, thus resulting in the elevation of intracellular reactive oxygen and the acceleration of cell death. Finally, PL displayed better antibacterial activity in carrot juice without adverse effect on its quality.

Application of non-thermal plasma for decontamination of thyme and paprika

The decontamination importance of spices as a widely used product in the world and the limitations of conventional decontamination methods conduct to find new and safe ways for microbial reduction of spices. Recently, cold plasma technology has been considered as a technique for disinfection in the food industry. In this study, microbial destruction of thyme and paprika through non-thermal plasma was investigated. The implemented method to create atmospheric cold plasma was dielectric barrier discharge (DBD). Plasma was applied to spices for 5 minutes. The results showed that by applying non-thermal plasma to thyme, total bacterial counts were reduced to 1.18 log cycle, but molds and yeasts were not changed. For paprika, considerable effects were not observed. It seems that cold plasma as an inexpensive, water-free and non-thermal method has the potential to reduce the bacterial contamination of thyme but further research is required to improve its effect. It is also possible to use DBD plasma treatment in combination with other technologies.

High pressure sensitization of heat-resistant and pathogenic foodborne spores to nisin

Today, there is no effective non-thermal method to inactivate unwanted bacterial spores in foods. High-Pressure (HP) process has been shown to act synergistically with moderate heating and the bacteriocin nisin to inactivate spores but the mechanisms have not been elucidated. The purpose of the present work was to investigate in depth the synergy of HP and nisin on various foodborne spore species and to bring new elements of understandings.For this purpose, spores of Bacillus pumilus, B. sporothermodurans, B. licheniformis, B. weihenstephanensis, and Clostridium sp. were suspended in MES buffer, in skim milk or in a liquid medium simulating cooked ham brine and treated by HP at 500 MPa for 10 min at 50 °C or 20 °C. Nisin (20 or 50 IU/mL) was added at three different points during treatment: during HP, during and or in the plating medium of enumeration. In the latter two cases, a high synergy was observed with the inhibition of the spores of Bacillus spp. The evaluation of the germinated fraction of Bacillus spp. spores after HP revealed that this synergy was likely due to the action of nisin on HP-sensitized spores, rather than on HP-germinated spores. Thus, the combination of nisin and HP can lead to Bacillus spp. spore inhibition at 20 °C. And Nisin can act on HP-treated spores, even if they are not germinated.This paper provides new information about the inhibition of spores by the combination of HP and nisin. The high synergy observed at low temperature has not been reported yet and could allow food preservation without the use of any thermal process.

Simultaneous analysis of 2Cs, 25-NBOHs, 25-NBOMes and LSD in seized exhibits using liquid chromatography–tandem mass spectrometry: A targeted approach

Blotter papers laced with lysergic acid diethylamide (LSD) have been abused traditionally for their hallucinogenic properties. In recent years, new psychedelic phenethylamines such as 2,5-dimethoxyphenethylamines (2C) and their N-benzylhydroxy (25-NBOH) and N-2-methoxybenzyl derivatives (25-NBOMe) have emerged in the illicit drugs market. Traditionally, gas chromatography–mass spectrometry (GC–MS) is regarded as the gold standard for illicit drugs analysis. However, with the emergence of new psychoactive substances (NPS) which are thermally labile (such as the 25-NBOH drugs which undergo thermal degradation to their respective 2C drugs), alternative non-thermal techniques have to be developed in order to prevent misidentification. In this study, a single, targeted, non-thermal analytical method using the liquid chromatography–tandem mass spectrometry (LC–MS/MS) to simultaneously identify these new phenethylamines and their derivatives was developed and validated. Twelve phenethylamines and their derivatives, as well as LSD were simultaneously analysed using the LC–MS/MS in a multiple reaction monitoring (MRM) detection mode. The method developed was validated and applied for the analysis of phenethylamines and their derivatives commonly found in seized exhibits such as blotter papers and Ecstasy tablets.

Plasma-enhanced steam reforming of different model tar compounds over Ni-based fusion catalysts.

Tar formation during biomass gasification is undesirable due to the decreased energy efficiency and increased costs for maintaining downstream equipment. The hybrid non-thermal plasma-catalysis method is considered to be a promising alternative, since it overcomes the disadvantages arising from both catalyst deactivation during catalytic reforming and the formation of undesirable liquid by-products in plasma reforming. SiO2- and ZSM-5-supported Ni-based catalysts with different Ni loadings (0.5, 1, 3, and 5 wt%) were prepared by thermal fusion and applied to the steam reforming of toluene. Different characterizations of fresh and spent catalysts including XRD, H2-TPR, N2 adsorption-desorption, SEM, TEM, XPS and TGA were conducted to show the properties of catalysts. The results indicated that Ni/ZSM-5 exhibited better performance than Ni/SiO2, due to the increased dispersion of Ni particles and the stronger metal-support interaction of Ni/ZSM-5, which was confirmed by the TEM and H2-TPR results. In addition, the performances of the catalysis-only (CatO), plasma-only (PlO), and in-plasma-catalysis (IPC) systems in steam reforming of different model tar compounds including benzene, toluene, furfural, naphthalene, fluorene and pyrene were compared using Ni(5 wt%)/ZSM-5. Obvious synergistic effects between DBD plasma and Ni(5 wt%)/ZSM-5 was observed for syngas production in the IPC system.