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This research provides a perspective on sludge-to-energy using sewage sludge (SS) and industrial wastewater sludge (IS) co-gasification in a pilot-scale fluidized bed gasifier with temperature controlled at (600–800 °C) using IS addition ratio (0%–60%), and steam-to-biomass ratio (S/B) (0–1.0). The experimental results show that the increase in thermal reaction activity occurred in concordance with the increase in the IS addition. The explanation for such phenomena is that relatively high catalytic Fe/Mn content in industrial wastewater sludge could lower the activation energy. Hydrogen production was increased from 9.1% to 11.94% with an increase in industrial wastewater sludge ratios from 0% to 60%. The produced gas heating value ranged from 4.84 MJ/Nm3 to 5.11 MJ/Nm3, which was coupled with the cold gas efficiency (CGE) ranging from 33.91% to 36.15%. Enhanced hydrogen production in sewage sludge and industrial wastewater sludge co-gasification is investigated in this study. • Sludge-to-energy using co-gasification has successfully developed. • Relatively high catalytic Fe/Mn content in sludge could lower the activation energy. • Hydrogen yield was increased with the industrial wastewater sludge addition increasing. • The produced gas heating value was ranged from 4.84 MJ/Nm3 to 5.11 MJ/Nm3. • The insight into enhanced syngas yield in co-sludge gasification was provided. [ABSTRACT FROM AUTHOR]

This work examines the hydrogen gas yield and trace pollutants partitioning in automobile shredder residue (ASR) catalytic gasification by fixed bed and fluidized bed gasifier with controlling at equilibrium ratio (ER) 0.2, temperature 900 °C, and 5%–15% prepared catalyst addition. Oyster shell (OS) is a valuable resource due to its higher calcium content that it could prepare as a catalyst for enhancing the hydrogen production in ASR gasification. In the case of the fixed bed gasifier experiments, the highest lower heating value (LHV) and syngas production were found at 900 °C and 10% OS catalyst addition. The maximum H 2 and CO composition were 6.57% and 5.97%, respectively. The LHV of syngas was approximately 4.43 MJ/Nm3. The fluidized bed gasifier could provide a good ASR decomposition and heat transfer behavior. The syngas yield results indicated the maximum H 2 and CO composition were 12.12% and 10.59%, respectively. It was obviously showed that the syngas production and energy conversion efficiency were enhanced by applying fluidized bed gasifier. The maximum produced gas LHV was 10.77 MJ/Nm3 as well as the cold gas efficiency (CGE) of produced gas was 71.62%. On the other hand, the volatile sulfur and chlorine speciation formed in ASR gasification were mainly partitioned in the solid and/or liquid phase. It implied that tested OS catalysts could inhibit the volatile sulfur and chlorine speciation emission in the produced gas as well as enhance the produced gas quality. In summary, this research could provide basic insight into enhanced syngas production and quality in ASR catalytic gasification using the prepared OS catalyst. • Oster shell catalyst containing high calcium content was successfully prepared. • The produced gas heating value was almost compliant with gaseous fuel criteria ranged from 7.72 to 10.77 MJ/Nm3. • This research provides basic insight into enhanced syngas production in ASR gasification using the OS catalyst. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the enhancement of tar and trace gaseous pollutants (e.g. hydrogen sulfide (H 2 S) and hydrogen chloride (HCl) removal efficiency derived from rice straw gasification using an integrated hot-gas cleaning system. A bubbling fluidized bed gasifier was used by controlling the temperature at 800 °C and equivalence ratio (ER) ranging 0.2 to 0.4. The hot gas cleaning system was operated at 250 °C and designed to combine three types of absorbents including zeolite, calcined dolomite, and activated carbon. Tar, H 2 S, and HCl removal efficiency and enhanced hydrogen production were also discussed. The experimental results indicated that light fraction tar removal efficiency was higher than 90% and the overall tar removal efficiency was approximately 70%. In the case of ER 0.4, the syngas tar content was decreased from 71.88 g/Nm3 (without hot gas cleaning system) to 16.53 g/Nm3 (with hot gas cleaning system). The tar removal efficiency is nearly 77% using the hot gas cleaning system. The HCl and H 2 S removal efficiency ranged from 94% to 98% and from 80.7% to 83.92%, respectively. In the case of ER 0.3 and with the hot gas cleaning system, the HCl and H 2 S concentrations in cleaned syngas gas were less than 40 ppm and 100 ppm, respectively. Meanwhile, the hydrogen concentration of produced gas was also increased from 6.82% to 9.83% with hot gas cleaning system used. It means that the hot gas cleaning system can effectively remove HCl and H 2 S from produced gas in gasification, but also it has good potential for improving syngas quality and enhancing gas turbine application in the future. Highlights • Hot gas cleaning system for removing trace pollutants has successfully developed. • The overall tar removal efficiency was nearly 70% by hot gas cleaning system. • The HCl and H 2 S removal efficiency were approximately 95% and 80%, respectively. • Hot gas cleaning system could play a key role in improving syngas quality. [ABSTRACT FROM AUTHOR]

The biodegradation of proteins in seawater requires various proteases which are commonly thought to be mainly derived from heterotrophic bacteria. We, however, found that protists showed a high protease activity and continuously produced trypsin-type enzymes. The free-living marine heterotrophic ciliate Paranophrys marina together with an associated bacterium was isolated and used for microcosm incubation with different concentrations of killed bacteria as food for 10 days. The results showed that the co-existence of the ciliate with its associated bacterium produced a significant protease activity in both cell-associated and cell-free fractions while that in the associated bacterium only microcosm was negligible. The protease profiles are different between cell-associated and cell-free fractions, and a trypsin-type enzyme hydrolyzing Boc-Val-Leu-Lys-MCA was detected throughout the period in the presence of ciliates. This suggests that ciliates release proteases into the surrounding environment which could play a role in protein digestion outside cells. It has been previously suggested that bacteria are the major transformers in seawater. We here present additional data which indicates that protists, or at least ciliates with their specific enzymes, are a potential player in organic matter degradation in water columns. [ABSTRACT FROM AUTHOR]

This research investigates the trace metals speciation, partitioning and removal in rice straw gasification equipped with an integrated hot gas cleaning (HGC) system. The experiments were conducted by fluidized bed gasifier and controlled at 800 °C with equivalence ratio (ER) varied between 0.2 and 0.4. The experimental results indicated that the concerned trace metals Zn, Cr, Cd, and Pb partitioning in the gas phase were increased significantly with an increase in ER. This is because the exothermic reaction could enhance the trace metals reacted with chlorine and/or sulfur as well as correspondingly formed highly volatile metals compounds. However, other tested metals Cu, Na, K, Ca, Mg partitioning was obviously decreased in the gas phase with ER increasing. These tested metals tend to form oxides speciation leading the variation in their partitioning characteristics. The XRD identification and thermodynamic equilibrium simulation results were also confirmed the tested metals speciation and partitioning characteristics. The dominant gaseous species produced from rice straw gasification, such as KCl (g) , NaCl (g) , KO (g) , K 2 O (g) , ZnCl 2(g) , CrO 2 Cl 2(g) , CuCl 2(g) , PbCl 2(g) , PbO (g) , and Cd (g) , were predicted by thermodynamic equilibrium model. The tested metals removal by adsorbents of hot gas cleaning system was found to be adsorbed in decreasing order as: K > Cr > Ca > Pb > Mg > Cd > Na > Zn > Cu. Activated carbon was used in hot gas cleaning system and showed a good performance for adsorbing tested metals, especially for Pb, Cd, Cr, Ca, K, and Mg. In summary, HGC system is proposed as an effective way for improving the syngas quality and reducing trace contaminants emission in rice straw gasification. • Concerned trace metal speciation and partitioning characteristic in rice straw gasification has been successfully developed. • The trace metals Zn, Cr, Cd, and Pb partitioning in the gas phase were increased with equivalence ratio increased. • The metals removal by the hot gas cleaning system was found in decreasing order as: K > Cr > Ca > Pb > Mg > Cd > Na > Zn > Cu. • Activated carbon showed a good performance for adsorbing Pb, Cd, Cr, Ca, K, and Mg. • The hot gas cleaning system could play a key role in removing concerned trace metals. [ABSTRACT FROM AUTHOR]

Thermal error always exists in a machine tool and accounts for a large part of the total error in the machine. Thermal displacement in X-axis on a CNC lathe controlled based on a rapid heating system is presented in this paper. Positive Temperature Coefficient (PTC) heating plates are installed on the X-axis of the machine. A control temperature system is constructed for rapid heating which further helps the thermal displacement to quickly reach stability. The system then continuously maintains stable compensation of the thermal error. The presented rapid heating technique is simpler than the compensation of machine thermal errors by interference in the numerical control system. Results show that the steady state of the thermal displacement in the X-axis can be acquired in a shorter time. In addition, thermal errors in constant and varying working conditions could be significantly reduced above 80% and 60%, respectively, compared to those without using the rapid heating. Therefore, the proposed method has a high potential for application on the CNC lathe machine for improving its precision. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gasification was able to recover 35.2 % to 65.3 % of aluminum. • At 700 °C and ER = 0.4 provide the largest volume of syngas about 69.42 %. • The majority of aluminum products after gasification include Al 2 O 3 (s) and AlCl 2 (g). • Al in syngas was presented as AlCl 2 (g), AlH(g), and Al 2 O(g). • As ER is increased, more Al 2 O 3 was formed thus Al recovery efficiency goes up. The standing pouch, a packaging material made of multiple layers of plastic and metal, presents a significant challenge for full recycling. Gasification shows promise as a method to recover aluminum from this type of waste and convert it into energy. This study aims to evaluate the efficiency of gasification in treating aluminum-containing plastic packages, and recovering aluminum while identifying the optimal combinations of temperature and equivalence ratio (ER) to achieve the best outcomes. The study achieved a conversion rate of 43.06 wt% to 69.42 wt% of the original waste mass into syngas, with aluminum recovery rates ranging from 35.2 % to 65.3 %. Temperature and ER alterations affected the product distribution, aluminum recovery rate, and aluminum partitioning in the products. The results indicated that the combination of 700 °C, ER = 0.4 would provide the largest amount of syngas about 69.42 %, which is the main product of the gasification process, and therefore, this combination is the most optimal for syngas-yielding purposes. Under the reclaiming aluminum is more prioritized, the combination of 800 °C, ER = 0.6 would be the most optimal condition, the majority of Al in fuel was found in char and fly ash were 67.5 % and 4.81 %, respectively. The study focused on the partitioning of aluminum during the gasification process, which was observed to mainly exist in the form of Al 2 O 3 (s), with gaseous species including AlCl 3 (g), AlH(g), and Al 2 O(g) due to their medium volatility. As the ER increased, the amount of O 2 also increased, leading to more Al 2 O 3 (s) formation. In conclusion, this research provides a foundation for further exploration of gasification as a means of energy conversion and metal recovery. [ABSTRACT FROM AUTHOR]

Purpose. The impact of a community pharmacist telephone follow-up intervention (PTFI) on clinical outcomes, pharmaceutical care, and costs for patients undergoing antibiotic treatment was studied. Methods. Patients receiving usual pharmacist intervention (UPI) were compared with PTFI patients in a multicenter, randomized, controlled trial. Results. Compared with the UPI group (n = 129), the PTFI group (n = 126) had more drug-related problems (DRPs) (PTFI = 53%, UPI = 8%; p < 0.001). Oral recommendations (PTFI = 52%, UPI = 6%; p < 0.001), as well as recognized (PTFI = 10%, UPI = 2%; p = 0.015) and study-specific (PTFI = 5%, UPI = 1%; p = 0.064) pharmaceutical advices, were issued for more patients. The mean difference in the change in the number of infectious symptoms between the two groups (-0.24 symptom, 95% confidence interval [CI] = -1.22 to 0.74) and the change in the infection severity score (mean difference = -0.05 unit, 95% CI = -0.35 to 0.25) were small and not statistically significant. Adherence to treatment and patient satisfaction did not differ across the two intervention groups. The incremental direct costs of the PTFI varied from $2.65 to $5.11 (Canadian dollars) per patient, depending on whether cognitive services were reimbursed. Conclusion. A telephone follow-up by community pharmacists during antibiotic therapy was simple and quick and created opportunities to intervene with patients, but it did not create a greater change in the number of infectious symptoms or the infection severity score than did usual care. [ABSTRACT FROM AUTHOR]

Thermal has a significant effect on high speed machine tools. When temperature grows up, it often causes processing errors and further reduces product quality. This paper aims to investigate magnitude of heat sources and temperature distribution in a horizontal lathe based on inverse method. In the present thermal model, there is not only consideration of spindle, but also analyzing relative structures. Simulated and experimental temperatures are used as input data to predict heat sources and temperature field. Effects of speed, number measured points, measurement errors, and measured distance on predicted results are analyzed. Results indicate that this inverse method can accurately estimate the heat sources based on two measured temperatures at front and rear outer rings. The trend of estimated heat sources is then compared to measured load rate. Results herein are useful information for designing horizontal lathe spindle and reducing thermal errors. [ABSTRACT FROM AUTHOR]

In this study, the employment of aqueous enzymolysis using alcalase with ethanolic ultrasonication extraction method was investigated. The cordycepin content was analyzed by using reversed‐phase high‐performance liquid chromatography with a diode array detector. The result showed that the highest cordycepin content of 0.4365±0.0309 mg/g could be obtained under extraction conditions including total enzyme volume of 240 μL, incubation time of 50 min, incubation temperature of 55 °C, and ultrasonic power of 840 W. The comparative studies of antioxidant activities of the extract were determined in terms of the DPPH free radical scavenging assay, ferric ion reducing power assay, and H2O2 scavenging assay. Additionally, the MTT assay was conducted to evaluate the anticancer activities of the extract, illustrating the cytotoxic property against Hep‐G2 cancer cells with the half‐maximal inhibitory concentration (IC50) value of 12.20±0.03 μg/mL compared to that of 0.36±0.03 μg/mL for ellipticine, MCF‐7 cancer cells with the IC50 value of 11.60±0.09 μg/mL compared to that of 0.51±0.04 μg/mL for ellipticine, and Lu cancer cells with the IC50 value of 34.50±0.25 μg/mL compared to that of 0.32±0.03 μg/mL for ellipticine. [ABSTRACT FROM AUTHOR]

Bacteria from the family Flavobacteriaceae often show low susceptibility to antibiotics. With the exception of two Chryseobacterium spp. isolates that were positive for the florfenicol resistance gene floR, no clinical resistance genes were identified by microarray in 36 Flavobacteriaceae isolates from salmonid fish that could grow in ≥ 4 mg/L florfenicol. Whole genome sequence analysis of the floR positive isolates revealed the presence of a region that contained the antimicrobial resistance genes floR, a tet(X) tetracycline resistance gene, a streptothricin resistance gene and a chloramphenicol acetyltransferase gene. In silico analysis of 377 published genomes for Flavobacteriaceae isolates from a range of sources confirmed that well-characterised resistance gene cassettes were not widely distributed in bacteria from this group. Efflux pump-mediated decreased susceptibility to a range of antimicrobials was confirmed in both floR positive isolates using an efflux pump inhibitor (phenylalanine-arginine β-naphthylamide) assay. The floR isolates possessed putative virulence factors, including production of siderophores and haemolysins, and were mildly pathogenic in rainbow trout. Results support the suggestion that, despite the detection of floR, susceptibility to antimicrobials in Flavobacteriaceae is mostly mediated via intrinsic mechanisms rather than the horizontally acquired resistance genes more normally associated with Gram-negative bacterial pathogens such as Enterobacteriaceae. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of international migration on job creation in the informal sector in Vietnam. Using the national representative household data on international migration in 2008, the results find no self-employment differential between migrant and non-migrant households. International migration matters only if business scale is taken into account. Estimations using the propensity score matching method reveal that Vietnam's migrant households are either poor or rich families. This points to the effectiveness of government labour export programmes designed to reduce poverty and the tendency of rich families to send children to study abroad. The results also show that international migration has no impact on entrepreneurship, and thus employment generation in the informal sector, raising concerns about the lasting impact of migration. [ABSTRACT FROM PUBLISHER]

Shiga toxin (Stx)-producing bacteria are important human pathogens that have been linked with cattle and associated food products. We recovered Stx-producing bacteria from 27.5% of cattle, 6.8% of water, and 2.3% of wildlife samples from a cattle production area during an 11-month period. Positive samples were found during every month and on 98% of sampling days. We recovered isolates from all cattle operations sampled, and prevalence within operations ranged from approximately 5 to 33%. Cattle prevalence was associated with the presence of Stx-producing bacteria in water and the production group and environment of cattle, with an interaction between production group and environment. Odds of recovering isolates from cattle were highest for groups of adult cows and their unweaned calves in pasture environments. Overall, 49 O serogroups were identified from 527 isolates. Seventy of the isolates contained virulence genes that encoded intimin and enterohemorrhagic Escherichia coli hemolysin. These were serogroups O111, O157, O109, O103, O145, O172, 084, 026, O108, O117, O126, O159, O5, O69, O74, O98, and O-rough. Our results suggest that the prevalence of Stx-producing bacteria can be relatively high in cattle, and associated factors may not be entirely similar to those reported for serotype O157:H7. Although Stx-producing bacteria were frequently detected, the strains may not be equally pathogenic for humans given the wide variety of serogroups and virulence genes. However, focusing on O157:H7 in food safety and surveillance programs may allow other Stx-producing bacteria, which appear to be widespread in cattle, to go undetected. [ABSTRACT FROM AUTHOR]