NOx removal and copper recovery from the leaching process for waste printed circuit boards: performance evaluation and potential environmental impact assessment.

Resource recovery is crucial for small- and medium-sized enterprises to attain a circular economy. The economic benefits of recovering precious metals from electronic waste, such as waste printed circuit boards (WPCBs), are hindered by secondary pollutant emissions from pretreatment processes. This study aims to recover copper from the WPCB acid leaching process and reduce NOx emissions through the use of a high gravity rotating packed bed (RPB). The results indicate that the copper recovery ratio increases to 99.75% through the displacement reaction between iron powder and copper nitrate. The kinetic analysis of copper dissolution was employed to simulate the NOx emissions during acid leaching, with an R-squared value of 0.872. Three oxidants, including H2O2(aq), ClO2(aq), and O3(g), with pH adjusted to different NaOH concentrations, were used to remove NOx. The greatest NOx removal rate was achieved using a 0.06 M NaOH solution, with a removal rate of 91.2% for ozone oxidation at a 152-fold gravity level and a gas-to-liquid (G/L) ratio of 0.83. The gas-side mass transfer coefficients (KGa) for NOx range from 0.003 to 0.012 1/s and are comparable to previous studies. The results of a life cycle analysis indicate that the NOx removal rate, nitric acid recycling rate, and copper recovery rate are 85%, 80%, and 100%, respectively, reducing the environmental impact on the ecosystem, human health, and resource depletion by 10% compared to a scenario with no NOx removal.

Avaliação do potencial erosivo de bebidas ácidas / Evaluation of the erosive potential of acid drinks

Objetivo: o presente estudo teve como objetivo avaliar, in vitro, o potencial erosivo para o esmalte dentário de bebidas ácidas, comumente ingeridas pela população e encontradas com frequência no comércio da grande Florianópolis, SC, Brasil. Método: a mensuração do potencial erosivo das bebidas foi realizada através da detecção do potencial hidrogeniônico (pH) e acidez titulável (AT). A amostra foi composta por refrigerantes à base de cola, Coca-Cola® e Pepsi®; isotônicos Gatorade®-morango e maracujá e Powerade®-mix de frutas; Chás industrializados Natural Tea®-limão e Chá Matte Leão®-natural; energéticos Red Bull® e Monster Energy®; sucos naturais de Laranja Pera e de Limão Taiti; água saborizada H2OH!®-sabor limão; e água mineral, para o grupo controle. O pH foi aferido com pHmetro digital (Sensoglass SP1800) e para a AT foi utilizado o método padronizado pelo Instituto Adolfo Lutz, todos os ensaios foram realizados em triplicata. Para a análise estatística descritiva, foram empregados teste t e a ANOVA. Resultados: os menores valores de pH foram encontrados para a bebida Coca-Cola® e suco de limão com 2,3. Para AT, as amostras que apresentaram os maiores valores foram os sucos naturais, com 35,1 para o suco de limão e 13,5 para o suco de laranja. Todas as bebidas analisadas possuem potencial erosivo ao esmalte dental, por apresentarem valores de pH menores que 5,5. Quanto as mensurações de AT, os sucos naturais apresentaram os maiores valores. Conclusão: todas as bebidas do estudo foram consideradas iminentemente erosivas à estrutura dental.(AU)

Objetivo: o presente estudo teve como objetivo avaliar, in vitro, o potencial erosivo para o esmalte dentário de bebidas ácidas, comumente ingeridas pela população e encontradas com frequência no comércio da grande Florianópolis, SC, Brasil. Método: a mensuração do potencial erosivo das bebidas foi realizada através da detecção do potencial hidrogeniônico (pH) e acidez titulável (AT). A amostra foi composta por refrigerantes à base de cola, Coca-Cola® e Pepsi®; isotônicos Gatorade®-morango e maracujá e Powerade®-mix de frutas; Chás industrializados Natural Tea®-limão e Chá Matte Leão®-natural; energéticos Red Bull® e Monster Energy®; sucos naturais de Laranja Pera e de Limão Taiti; água saborizada H2OH!®-sabor limão; e água mineral, para o grupo controle. O pH foi aferido com pHmetro digital (Sensoglass SP1800) e para a AT foi utilizado o método padronizado pelo Instituto Adolfo Lutz, todos os ensaios foram realizados em triplicata. Para a análise estatística descritiva, foram empregados teste t e a ANOVA. Resultados: os menores valores de pH foram encontrados para a bebida Coca-Cola® e suco de limão com 2,3. Para AT, as amostras que apresentaram os maiores valores foram os sucos naturais, com 35,1 para o suco de limão e 13,5 para o suco de laranja. Todas as bebidas analisadas possuem potencial erosivo ao esmalte dental, por apresentarem valores de pH menores que 5,5. Quanto as mensurações de AT, os sucos naturais apresentaram os maiores valores. Conclusão: todas as bebidas do estudo foram consideradas iminentemente erosivas à estrutura dental.(AU)

Area-Selective Depolymerization of Hydroxycinnamates Visualized by Raman Imaging in Miscanthus sinensis cv. Cell Wall.

Lignin-carbohydrate complexes (LCCs) are regarded as a barrier for lignocellulosic biomass refinery. Here, confocal Raman microspectroscopy has been used to visualize the dissolution of hydroxycinnamates (HCMs) incorporated into LCCs by ether and ester bonds for energy crops Miscanthus sinensis cv. during successive NaOH (2.5% w/w) treatment. Raman spectral analysis indicated that mild NaOH treatment resulted in a higher proportion of HCM depolymerization in highly lignified middle lamella areas (>66.0%) than carbohydrate-abundant secondary walls. Furthermore, Raman imaging revealed preferential depolymerization of lignin from the sclerenchyma fiber (Sf) and parenchyma (Par) secondary wall with an increment of treatment time from 0 to 25 min, while middle lamella areas of Sf and Par were less affected where the depolymerization of HCMs was closely related with that of lignin (coefficient factors > 0.96). A better understanding of the depolymerization behavior for HCMs accompanied by lignin depolymerization was important to break LCC bonds in herbaceous biomass efficiently.

Transformation of hazardous sacred incense sticks ash waste into less toxic product by sequential approach prior to their disposal into the water bodies.

Incense sticks ash is one of the most unexplored by-products generated at religious places and houses obtained after the combustion of incense sticks. Every year, tonnes of incense sticks ash is produced at religious places in India which are disposed of into the rivers and water bodies. The presence of heavy metals and high content of alkali metals challenges a potential threat to the living organism after the disposal in the river. The leaching of heavy metals and alkali metals may lead to water pollution. Besides this, incense sticks also have a high amount of calcium, silica, alumina, and ferrous along with traces of rutile and other oxides either in crystalline or amorphous phases. The incense sticks ash, heavy metals, and alkali metals can be extracted by water, mineral acids, and alkali. Ferrous can be extracted by magnetic separation, while calcium by HCl, alumina by sulfuric acid treatment, and silica by strong hydroxides like NaOH. The recovery of such elements by using acids and bases will eliminate their toxic heavy metals at the same time recovering major value-added minerals from it. Here, in the present research work, the effect on the elemental composition, morphology, crystallinity, and size of incense sticks ash particles was observed by extracting ferrous, followed by extraction of calcium by HCl and alumina by H2SO4 at 90-95 °C for 90 min. The final residue was treated with 4 M NaOH, in order to extract leachable silica at 90 °C for 90 min along with continuous stirring. The transformation of various minerals phases and microstructures of incense sticks ash (ISA) and other residues during ferrous, extraction, calcium, and alumina and silica extraction was studied using Fourier transform infrared (FTIR), dynamic light scattering (DLS), X-ray fluorescence (XRF), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and inductively coupled plasma-optical emission spectroscopy (ICP-OES). DLS was used for analyzing the size during the experiments while FTIR helped in the confirmation of the formation of new products during the treatments. From the various instrumental analyses, it was found that the toxic metals present in the initial incense sticks ash got eliminated. Besides this, the major alkali metals, i.e., Ca and Mg, got reduced during these successive treatments. Initially, there were mainly irregular shaped, micron-sized particles that were dominant in the incense sticks ash particles. Besides this, there were plenty of carbon particles left unburned during combustion. In the final residue, nanosized flowers shaped along with cuboidal micron-sized particles were dominant. present in If, such sequential techniques will be applied by the industries based on recycling of incense sticks ash, then not only the solid waste pollution will be reduced but also numerous value-added minerals like ferrous, silica, alumina calcium oxides and carbonates can be recovered from such waste. The value-added minerals could act as an economical and sustainable source of adsorbent for wastewater treatment in future.

Phosphorus removal from wastewater using Ca-modified attapulgite: Fixed-bed column performance and breakthrough curves analysis.

The adsorbent calcium-modified attapulgite (Ca-GAT) prepared by calcium chloride modification and high temperature treatment (700 °C) has proved to remove phosphorus in low-concentration phosphorus wastewater in batch adsorption experiments. Dynamic adsorption performance and industrial application potential still need further determination. This study explored the effects of various parameters on the dynamic phosphorus adsorption, including initial phosphate concentration (2-10 mg/L), flow rate (1-3 mL/min) and adsorption bed height (2-6 cm). Phosphorus adsorption ability improved and the breakthrough time increased with the increase of bed height, flow rate, and a decrease in initial phosphorus concentration. Breakthrough curves fitted four models, the Adams-Bohart, Thomas, Yoon-Nelson and Bed depth service time (BDST). The maximum adsorption amount determined by the Thomas model obtained 13.477 mg/g. The saturated fixed-bed column were regenerated with NaOH, NaOH + NaCl and HCl, among which 0.5 mol/L NaOH had the best regeneration effect. During the utilization of a large fixed-bed to treat the actual membrane bioreactor (MBR) effluent, the breakthrough point (0.5 mg/L) was obtained after 177 h. These results implied that Ca-GAT had an application potential for the treatment of low-concentration phosphorus wastewater (2 mg/L).

[Distribution Characteristics of Soil Phosphorus Forms and Phosphatase Activity at Different Altitudes in the Soil of Water-Level-Fluctuation Zone in Pengxi River, Three Gorges Reservoir].

Phosphatases play important roles in converting organic phosphorus into inorganic phosphorus in soil. However, studies from this perspective on the water-level-fluctuation zone (WLFZ) of the Three Gorges Reservoir are limited. In this study, phosphatase activity and the forms of phosphorus were analyzed. Soil samples were collected in the river basin of the Penxi River in the WLFZ during a drying period. The correlation between phosphatase activity and phosphorus forms and the impacts of phosphatase activity on the phosphorus forms were analyzed. The results showed that the contents of H2O-Pi, NaHCO3-Pi, and NaOH-Pi in the soils of the WLFZ were higher than those in the soils by the river. In addition, a higher altitude resulted in higher contents of bio-enzymatically hydrolysable phosphorus and NaOH-Po. Furthermore, redundancy analysis (RDA) showed that the contents of organic matter and amorphous Fe and Mn were the main factors affecting soil organic phosphorus forms. The average activities of acid phosphomonoesterase (ACP), alkaline phosphomonoesterase (ALP), phosphodiesterase (PDE) (all in p-NP), and phytase (PAE) (in P) in the soils of the WLFZ were 1.40, 2.60, 0.44, and 11.43 µmol·(g·h)-1, respectively. Moreover, the activities of different phosphatases increased with altitude. Soil plant biomass and microbial biomass were important reasons for the difference in spatial distribution of phosphatase activity in the soil of the WLFZ. Phosphatase activities were significantly positively correlated with the contents of organic phosphorus forms but negatively correlated with the content of bioavailable phosphorus. A higher soil phosphatase activity and a lower content of bioavailable phosphorus were usually detected in soil samples taken at a higher altitude. In the early stage of flooding, phosphatase converted organic phosphorus into inorganic phosphorus at a relatively high rate, and the risk of phosphorus release to the overlying water body was also high. This study contributed to a comprehensive understanding of the geochemical cycle of soil phosphorus in the soil of the WLFZ.

Efficient chlorinated alkanes degradation in soil by combining alkali hydrolysis with thermally activated persulfate.

Alkali activation is the most commonly used activation method for persulfate (PS) in in-situ remediation. However, the role of alkali in pollutant degradation is still elusive, limiting the optimization of relevant remediation strategies. In this study, we found that chlorinated alkanes (e.g., tetrachloroethane (TeCA)) could be efficiently degraded by thermal-alkali activation of PS. The main role of alkali was not activating PS but hydrolyzing the chlorinated alkanes, which was evidenced by the immediate conversion of TeCA into trichloroethylene (TCE) with NaOH and PS or with sole NaOH solution. Electron paramagnetic resonance analysis also showed that with a high NaOH/PS molar ratio (4:1) the intensity of oxidative radicals decreased, implying that high levels of alkali did not favor the formation of free radicals. Interestingly, better degradation of TeCA and its product TCE was observed by the combination of alkaline hydrolysis and thermal activation of PS (where alkali was added 6 h before PS rather than simultaneously) in comparison to thermal-alkali activation of PS. This study provides new insights into the remediation of chlorinated alkane-contaminated soils by in-situ chemical oxidation.

A new method for phosphate purification for oxygen isotope ratio analysis in freshwater and soil extracts using solid-phase extraction with zirconium-loaded resin.

RATIONALE: Phosphate (PO4 ) oxygen isotope (δ18 OPO4 ) analysis is increasingly applied to elucidate phosphorus cycling. Due to its usefulness, analytical methods continue to be developed and improved to increase processing efficiency and applicability to various sample types. A new pretreatment procedure to obtain clean Ag3 PO4 using solid-phase extraction (SPE) with zirconium-loaded resin (ZrME), which can selectively adsorb PO4 , is presented and evaluated here. METHODS: Our method comprises (1) PO4 concentration, (2) PO4 separation by SPE, (3) cation removal, (4) Cl- removal, and (5) formation of Ag3 PO4 . The method was tested by comparing the resulting δ18 OPO4 of KH2 PO4 reagent, soil extracts (NaHCO3 , NaOH, and HCl), freshwater, and seawater with data obtained using a conventional pretreatment method. RESULTS: PO4 recovery of our method ranged from 79.2% to 97.8% for KH2 PO4 , soil extracts, and freshwater. Although the recovery rate indicated incomplete desorption of PO4 from the ZrME columns, our method produced high-purity Ag3 PO4 and accurate δ18 OPO4 values (i.e., consistent with those obtained using conventional pretreatment methods). However, for seawater, the PO4 recovery was low (1.1%), probably due to the high concentrations of F- and SO4 2- which interfere with PO4 adsorption on the columns. Experiments indicate that the ZrME columns could be regenerated and used repeatedly at least three times. CONCLUSIONS: We demonstrated the utility of ZrME for purification of PO4 from freshwater and soil extracts for δ18 OPO4 analysis. Multiple samples could be processed in three days using this method, increasing sample throughput and potentially facilitating more widespread use of δ18 OPO4 analysis to deepen our understanding of phosphorus cycling in natural environments.

Tillage, green manure and residue retention improves aggregate-associated phosphorus fractions under rice-wheat cropping.

The sustainability of the rice-wheat system is threatened due to the deterioration of soil health and emergence of new challenges of climate change caused by low nutrient use efficiency and large scale burning of crop residues. The conservation agriculture based on tillage intensity, crop residue retention and raising green manuring (GM) crops during the intervening period between wheat harvest and rice establishment offers opportunities for restoration of phosphorus (P) dynamics and stimulate phosphatase activities within the macro-and micro-aggregates. Phosphorus and phosphatase activities in the soil aggregates affected by different residue management practices remain poorly understood. Thus, soil samples were obtained after a five-year field experiment to identify the effect of tillage, green manure and residue management on aggregate-associated phosphorus fractions. Four main plot treatments in rice included combination of wheat straw and GM were conventional till puddled transplanted rice (PTR) with no wheat straw (PTRW0), PTR with 25% wheat stubbles retained (PTRW25), PTR without wheat straw and GM (PTRW0 + GM), and PTR with wheat stubbles and GM (PTRW25 + GM). Three sub-plots treatments in the successive wheat crop were conventional tillage (CT) with rice straw removed (CTWR0), zero tillage (ZT) with rice straw removed (ZTWR0) and ZT with rice straw retained as surface mulch (ZTWR100). Results of the present study revealed significantly higher phosphorus fractions (HCl-P, NaHCO3-Pi and NaOH-Po) in treatment PTRW25 + GM and ZTWR100 compared with PTRW0/CTWR0 within both macro- and micro-aggregates. The total phosphorus (P), available P, alkaline phosphatase and phytin-P were significantly higher under ZTWR100 than CTWR0. The principal component analysis identified NaOH-Po, NaHCO3-Pi and HCl-P as the dominant and reliable indicators for evaluating P transformation within aggregates under conservation agriculture-based practices.

Application of Hydrothermal Alkaline Treatment for Destruction of Per- and Polyfluoroalkyl Substances in Contaminated Groundwater and Soil.

Hydrothermal alkaline treatment (HALT) can effectively degrade per- and polyfluoroalkyl substances (PFASs) present in aqueous film-forming foam (AFFF). However, information is lacking regarding the treatment of PFASs in actual groundwater and soil from AFFF-impacted sites, especially for complex soil matrices. Given the lack of studies on direct soil treatment for PFAS destruction, we herein applied HALT to two groundwater samples and three soil samples from AFFF-impacted sites and characterized the destruction of PFASs using high-resolution mass spectrometry. Results showed that the 148 PFASs identified in all collected field samples, including 10 cationic, 98 anionic, and 40 zwitterionic PFASs, were mostly degraded to nondetectable levels within 90 min when treated with 5 M NaOH at 350 °C. The near-complete defluorination, as evidenced by fluoride release measurements, confirmed the complete destruction of PFASs. While many structures, including perfluoroalkyl carboxylic acids and polyfluorinated substances, were readily degraded, perfluoroalkyl sulfonates (PFSAs, CnF2n+1-SO3-), most notably with short chain lengths (n = 3-5), were more recalcitrant. Rates of PFSA destruction in groundwater samples were similar to those measured in laboratory water solutions, but reactions in soil were slow, presumably due to base-neutralizing properties of the soil. Further, the degradation of PFASs in groundwaters and soils was found to be a function of reaction temperature, NaOH concentration, and reaction time. These findings have important implications for the remediation of AFFF-impacted sites.

A 128 × 128 Current-Mode Ultra-High Frame Rate ISFET Array With In-Pixel Calibration for Real-Time Ion Imaging.

An ultra-high frame rate and high spatial resolution ion-sensing Lab-on-Chip platform using a 128 × 128 CMOS ISFET array is presented. Current mode operation is employed to facilitate high-speed operation, with the ISFET sensors biased in the triode region to provide a linear response. Sensing pixels include a reset switch to allow in-pixel calibration for non-idealities such as offset, trapped charge and drift by periodically resetting the floating gate of the ISFET sensor. Current mode row-parallel signal processing is applied throughout the readout pipeline including auto-zeroing circuits for the removal of fixed pattern noise. The 128 readout signals are multiplexed to eight high-sample-rate on-chip current mode ADCs followed by an off-chip PCIe-based readout system on a FPGA with a latency of 0.15 s. Designed in a 0.35 µm CMOS process, the complete system-on-chip occupies an area of 2.6 × 2.2 [Formula: see text] with a pixel size of 18 × 12.5 µ[Formula: see text] and the whole system achieves a frame rate of 3000 fps which is the highest reported in the literature for ISFET arrays. The platform is demonstrated in the application of real-time ion-imaging through the high-speed visualization of sodium hydroxide (NaOH) diffusion in water at 60 fps on screen in addition to slow-motion playback of ion-dynamics recorded at 3000 fps.

Evaluating the effects of the adulterants in milk using direct-infusion high-resolution mass spectrometry.

Milk is an extremely complex food, capable of providing essential nutrients as well as being an important source of energy, and high-quality proteins and fats. Due to advances in technology, and to meet the increasing demand, production costs have increased, turning milk into a target of adulterations. Routine methods usually applied to certify the quality of the milk are restricted to microbiological tests, and assays that attest the nutritional composition within the expected values. However, potentially harmful byproducts generated by adulterating substances in general are not detected through these methodologies. In this contribution, we simulated the adulteration of freshly produced milk samples with four adulterants whose use already had reported for extended shelf life: formaldehyde, hydrogen peroxide, sodium hydroxide, and sodium hypochlorite. These samples were submitted to direct-infusion high-resolution mass spectrometry analysis and multivariate statistical analysis. This approach allows the characterization of a series of molecules modified by the adulterants, what demonstrates how these species affect the nutritious characteristics of this product.

Comparison and analysis of several wet scrubbing solutions to remove methyl mercaptan.

Wet scrubbing is regarded as an effective method to remove hydrophobic organic odorants. The focus of wet scrubbing is to choose an appropriate scrubbing liquid. In this study, methyl mercaptan (CH3SH) was selected as a representative hydrophobic organic odorant for treatment by wet scrubbing using several types of scrubbing solution: ethanol (C2H5OH), lead acetate ((CH3COO)2Pb), sodium hypochlorite (NaClO), and sodium hydroxide (NaOH). A comparative analysis of the treatment efficiency, operation cost, and environmental impact was conducted. Results of the technical and economic comparison indicate that the C2H5OH solution is the best choice of scrubbing solution among those tested. These findings serve as a reference for engineering design and operation for the removal of hydrophobic organic odorants.

Internal phosphorus load in a Mexican reservoir through sediment speciation analysis.

Since the sequential extraction of phosphorus (P) in sediment makes it possible to determine the P potentially available for release, in this paper, we evaluate the fractions of P in sediment profiles from Valle de Bravo reservoir, a eutrophic lake in central Mexico to determine the contributions of each fraction to the internal P load (IPL). The P fractionation scheme employs sequential extractions of sediment with O2-free water (MilliQ), bicarbonate-dithionite (BD), sodium hydroxide (NaOH), hydrochloric acid (HCl), and potassium persulfate (K2S2O8-) to obtain five P fractions. A monitoring of redox potential (Eh), pH, and total phosphorus (TP) in the bottom water of the reservoir indicated variations of these parameters during the year, observing that as Eh decreased, the P concentration increased, it was also observed that when increasing pH, P concentration also increased. Analyzing the behavior of fractions of P in sediment profiles, we found that the dominant fractions are those bound to iron and aluminum oxides, corresponding to approximately 50% of total P since P concentrations of these fractions were twice as high in the top 5 cm of the sediment profiles and decreased with increasing depth. Considering the variations of Eh and pH in the bottom water of the reservoir and that these parameters are factors that control the release of P with the fractions of P bound to Fe/Mn and Al/Fe oxides, we concluded that these fractions contribute most to P potentially available for release in the reservoir, representing a possible IPL of 23.5 ± 1.4 t/year.

Evaluation of alkaline electrolyzed water to replace traditional phosphate enhancement solutions: Effects on water holding capacity, tenderness, and sensory characteristics.

Sixty-four pork loins were randomly assigned to one of four treatments to evaluate the use of alkaline electrolyzed reduced water as a replacement for traditional enhancement solutions. Treatments included: alkaline electrolyzed reduced water (EOH; pH≈11.5), EOH plus 2.5% potassium-lactate (EOK), industry standard (IS; 0.35% sodium tri-polyphosphate, 0.14% sodium chloride, 2.5% potassium-lactate), and no enhancement (CON). After enhancement (targeting 110%) and rest period, chops were cut (2.54-cm) to test treatment effects on water holding capacity, Warner-Bratzler shear force (WBSF), and sensory attributes. Despite its alkaline nature EOH chops exuded more water (P<0.05) than EOK, IS, or CON chops. Control chops were similar (P>0.05) to EOK, however CON and EOK both lost more moisture (P<0.05) than IS. The use of alkaline electrolyzed reduced water did not improve WBSF or sensory characteristics compared to IS treated chops. As a stand-alone enhancement solution alkaline electrolyzed reduced water was not a suitable replacement for industry standard solutions.

Pt-Bi decorated nanoporous gold for high performance direct glucose fuel cell.

Binary PtBi decorated nanoporous gold (NPG-PtBi) electrocatalyst is specially designed and prepared for the anode in direct glucose fuel cells (DGFCs). By using electroless and electrochemical plating methods, a dense Pt layer and scattered Bi particles are sequentially coated on NPG. A simple DGFC with NPG-PtBi as anode and commercial Pt/C as cathode is constructed and operated to study the effect of operating temperatures and concentrations of glucose and NaOH. With an anode noble metal loading of only 0.45 mg cm-2 (Au 0.3 mg and Pt 0.15 mg), an open circuit voltage (OCV) of 0.9 V is obtained with a maximum power density of 8 mW cm-2. Furthermore, the maximum gravimetric power density of NPG-PtBi is 18 mW mg-1, about 4.5 times higher than that of commercial Pt/C.

NaOH-free debittering of table olives using power ultrasound.

A major drawback to the extension of NaOH-free olive debittering is its lengthy processing. In this research, the power ultrasound efficacy was investigated in a laboratory scale to accelerate this process. Olive fruits were sonicated in water or brine (15% NaCl). The effects of ultrasound-assisted debittering (UAD) were evaluated on olives physicochemical and textural properties in comparison with conventional debittering (CD). In UAD, however, the removal rate of phenolic compounds, which cause olives natural bitterness, increased significantly and as a result, the processing time decreased by 37.8% and 38.6% when debittering was done in water and brine, respectively. The chemical compositions, fatty acids profile, total color differences, Firmness and other textural parameters of UAD-treated samples remained unchanged and their antioxidant activity was significantly higher in comparison with CD-treated samples. Remarkably, UAD was able to speed up and promote NaOH-free olive debittering, without causing any undesirable changes.

Testing the degradation effects of three reagents on various antineoplastic compounds.

OBJECTIVE: Studies for decontamination of antineoplastic compounds have been conducted for decades. Nevertheless, recent studies indicate the contamination of work place in hospitals, and the exposure of workers. In this study, to develop an effective cleaning method for contaminated environments, the degradation efficacies of antineoplastic compounds by reagents were evaluated. METHODS: The degradation efficacies of various combinations of three reagents (sodium hypochlorite, sodium thiosulfate, and sodium hydroxide) were evaluated with four antineoplastic compounds (cyclophosphamide, epirubicin, cisplatin, and carboplatin). The residues of antineoplastic compounds were measured with high-performance liquid chromatography. RESULTS: Of the three reagents, sodium hypochlorite was the most effective to all antineoplastic compounds used in this study. Although sodium hypochlorite degraded 86.6% of cyclophosphamide, it degraded other three antineoplastic compounds completely. The combination with sodium hypochlorite and sodium thiosulfate degraded only 3.3% of cyclophosphamide, since sodium thiosulfate inhibited the degradation ability of sodium hypochlorite. Similarly, the combinations used in all three reagents failed to degrade cyclophosphamide. CONCLUSION: Although three of four antineoplastic compounds were degraded successfully, any combinations of three reagents could not degrade cyclophosphamide completely. However, the addition of sodium thiosulfate which inhibits the corrosion of metal by sodium hypochlorite is essential for daily cleaning. Therefore, the evaluation of reaction time before the addition of sodium thiosulfate may be required. We will continue to investigate the reagents for degradation.

[Evaluating risk of health disorders in workers engaged into polyvinyl chloride, vinyl chloride and caustic soda production (according to data collected by polls)].

The authors represent data of automated system for quantitative risk evaluation of main pathologic syndromes in workers engaged into polyvinyl chloride, vinyl chloride and caustic soda production. Vinyl chloride and mercury levels at the investigation time corresponded with MAC. Relationship was seen between value of arterial hypertension risk and duration of contact with both vinyl chloride and mercury. Risk values for functional disorders of liver, endocrine system and nervous system were in weak correlation with length of exposure to mercury at work. Workers exposed to mercury appeared to have lower self-estimation of health state and higher dissatisfaction with the work.