Effect of type of activating agent on properties of activated carbon prepared from digested solid waste.

Anaerobic digestion has been proved to be a widely used and effective technology. The main challenge for the sustainable biogas industry is to find ways to efficiently recycle and utilize the anaerobic digestate. The conversion of digestion products into activated carbon seems to be an attractive way. Therefore, the present study focused on assessing the potential of digested solids as a promising source of activated carbon using a range of activators including KOH, ZnCl2 and H3PO4. The activated carbon prepared from digested solids was subjected to an activation process to investigate the physicochemical and surface properties of the resulting activated carbon. The results showed that KOH appeared to be the best activator for producing activated carbon from high silica precursors such as digested solids. The effectiveness of KOH activation can be attributed to the ability of K to readily form poorly layered compounds with carbon, as well as a significant increase in the number of porosities during KOH activation due to the violent reaction of KOH with C and the volatilization of the inorganic minerals in the digested char. The KOH activated sample had the lowest La and Lc, which means it had the theoretically largest specific surface area. This study provides experimental basis and theoretical guidance for the conversion of digested solids into high value-added activated carbon.

Performance of volatile fatty acids production from food waste at the presence of alkyl ethoxy polyglycosides and sodium dodecyl sulfate.

In the current context of technological and industrial development, strategies for sustainable development and resource utilization have become increasingly important. FW anaerobic fermentation (Fermentation of Wastes) is a process that utilizes organic waste for biotransformation and is widely used for the production of volatile fatty acids (VFAs). Volatile fatty acids (VFAs) are a kind of high value-added product generated from anaerobic fermentation process, and has extensive applications in chemical synthesis and electricity generation. This study investigated the performance of VFAs production from food waste at the presence of alkyl ethoxy polyglycosides (AEG) and sodium dodecyl sulfate (SDS). The highest yield of VFAs was obtained at 0.1 g AEG/g TS (14.53 g COD/L), which increased by 25.80% than the Blank. But inhibited phenomenon was observed at other reactors with relatively low yield and delayed fermentation time. The inhibition of lactate's production and bioconversion delayed the fermentation time, and SDS has changed the acidogenic fermentation type from lactate-butyrate fermentation to acetate fermentation. In addition, more organic matter dissolved in the fermentation liquor with the addition of AEG and SDS, but the hydrolysis and acidification of polysaccharide were inhibited to some extent. Microbial community analysis showed that the abundance of key bacteria Clostridium has significantly decreased from 82.71% (Blank) to 33.54% (AEG) and 23.72% (SDS), leading to low VFAs production performance.

Fermentation broth of food waste: A sustainable electron donor for perchlorate biodegradation.

Microbial reduction has been considered an effective way to remove perchlorate (ClO4-), during which, additional electron donors and carbon sources are required. This work aims to study the potential of fermentation broth of food waste (FBFW) serving as an electron donor for ClO4- biodegradation, and further investigates the variance of the microbial community. The results showed that FBFW without anaerobic inoculum at 96 h (F-96) exhibited the highest ClO4- removal rate of 127.09 mg/L/d, attributed to higher acetate and lower ammonium contents in the F-96 system. In a 5 L continuous stirred-tank reactor (CSTR), with a 217.39 g/m3·d ClO4- loading rate, 100% removal efficiency of ClO4- was achieved, indicating that the application of FBFW in the CSTR showed satisfactory performance for ClO4- degradation. Moreover, the microbial community analysis revealed that Proteobacteria and Dechloromonas contributed positively to ClO4- degradation. Therefore, this study provided a novel approach for the recovery and utilization of food waste, by employing it as a cost-effective electron donor for ClO4- biodegradation.

Integration of hydrothermal and pyrolysis for oily sludge treatment: A novel collaborative process.

In this study, hydrothermal treatment and in situ pyrolysis were combined to develop a novel collaborative process (HCP treatment method). In a self-designed reactor, the HCP method was used to study the influences of hydrothermal temperature and pyrolysis temperature on the product distribution of OS. The products from the HCP treatment of OS were compared with that from the traditional pyrolysis. In addition, the energy balance in the different processes of treatment was analyzed. The results showed that compared to the traditional pyrolysis method, the gas products obtained after HCP treatment achieve a higher H2 production. As the hydrothermal temperature raising from 160 to 200 °C, the H2 production showed an increase from 4.14 to 9.83 ml/g. In addition, GC-MS analysis showed that the content of olefins from the HCP treatment oil was increased from 1.92% to 6.01% compared to traditional pyrolysis. Energy consumption analysis showed that only 55.39% energy consumption of traditional pyrolysis is required for treating 1 kg OS by employing the HCP treatment at 500 °C. All results indicated that the HCP treatment is a clean production process of OS with low energy consumption.

Characterization of heavy metals and oil components in the products of oily sludge after hydrothermal treatment.

In this study, the method combining hydrothermal treatment (HT) and in-situ mechanical compression (MC) is used to treat oily sludge. The possible transfer and reaction pathways of different oil components during the process of HT&MC were investigated. In addition, the leaching toxicity, distribution, and risk of heavy metals in oily sludge treated in different temperatures and residence times were evaluated. The results revealed that siloxane and heavy oil components are left in the solid residue, and the light oils and oils with hydrophilic groups are transferred to hydrothermal fluids. The content of Cd, Cr, Pb, and Zn in form of F4 (residual) in the solid residue obtained at a hydrothermal temperature of 240 °C and residence time of 60 min increased by 7.37%, 1.21%, 3.06%, and 9.97%. This reduced the biological availability and environmental risk of heavy metals in the treated oily sludge. Meanwhile, the result of FT-IR illustrated an increase in hydroxyl groups of alcohols, phenols and organic acids, which have a beneficial effect on the adsorption of heavy metals and other pollutants. All results indicated that HT&MC might be a suitable pretreatment method for the stabilization of heavy metals in oily sludge.

Critical assessment of plasma tar reforming during biomass gasification: A review on advancement in plasma technology.

The contamination of producer gas with tar due to inefficient removal methods remains a major challenge in the bioenergy industry and a critical barrier, hindering commercial applications of biomass gasification technology. Single syngas treatment through primary and secondary tar removal method is insufficient to produce a tar free syngas. Currently widely applied tar removal methods are catalytic reforming and plasma reforming. Though both methods have hindrances of fast catalyst deactivation due to coke deposition and reduced syngas selectivity with large quantities of undesired liquid products from plasma reforming. Our review paper showed that hybrid plasma catalysis could be a breakthrough in tar reforming methods and overcome major drawbacks. Though, very little work on review articles have reported merging non-thermal plasma and heterogeneous catalyst. Plasma catalysis offers an inexpensive viable future technology of tar reforming through biomass gasification. The article assessed in-depth the synergistic effect created during the interaction of energetic plasma species and catalyst radicals in tar reforming. Review results show that merging plasma with catalysts noticeably Nickel, Non-nickel metal catalyst and zeolites gave pleasant results of tar conversion efficiency, improved gas selectivity and improved catalyst stability.

Co-pyrolysis of biomass and waste tires under high-pressure two-stage fixed bed reactor.

The distribution of biomass pyrolysis products under high pressure have rarely been reported. In this study, the effect of pressure on the product distribution of pine sawdust (PS) pyrolysis was studied. The synergistic effect of the side wall rubber (SWR) and PS was confirmed under pressurized conditions. Calcined bottom ash (CBA) and SWR char (SWRC) were used to enhance the quality of the pressurized co-pyrolysis products. The PS and SWR pyrolysis chars obtained under high pressure conditions exhibited serious melting and cross-linking problem. The CO2 content decreased to 19.96 vol% in co-pyrolysis gas with the CBA/SWRC7/3 catalyst. The water content decreased by 85.71% after the SWRC catalyst in the pressurized co-pyrolysis process. Compared with the concentration of benzene in PS and SWR oil, the concentration of benzene in SWR/PS7/3 oil without catalysts increased by 9.57 times and 0.25 times, respectively.

Hydrothermal treatment combined with in-situ mechanical compression for floated oily sludge dewatering.

Due to the high moisture content of the oily sludge, the conventional use of oily sludge treatment presents poor feasibility in industrial applications. Hence, finding an efficient and energy-saving technology is still an urgent need for the dewatering of oily sludge. In this paper, an innovative method combining hydrothermal treatment (HT) and in-situ mechanical compression (MC) for dewatering of floated oily sludge (FOS) was proposed. Series of experiments on HT&MC were conducted to verify the method. 77-96 wt% of water can directly be separated from FOS by the HT&MC treatment under the temperature of 120-240 °C and residence times of 10-60 min. The bound water content in raw and HT&MT treated FOS were measured by employing the differential scanning calorimetry (DSC) to evaluate the dewatering ability. The result of DSC illustrates the freezing peaks shifted from -11.1 °C to -21.2 °C as the diameter of water droplets reduced. Meanwhile, the comprehensive characterization analysis of products, including chemical oxygen demand (COD), NH4+-N, and gas chromatograph (GC) were conducted. All results indicated that HT&MC is advisable for dewatering of oily sludge.

Copyrolysis of Biomass and Coal: A Review of Effects of Copyrolysis Parameters, Product Properties, and Synergistic Mechanisms.

Concerns in the last few decades regarding the environmental and socioeconomic impacts of the dependence on fossil fuels have resulted in calls for more renewable and alternative energy sources. This has led to recent interest in copyrolysis of biomass and coal. Numerous reviews have been found related to individual pyrolysis of coal and biomass. This review deals mainly with the copyrolysis of coal and biomass and then compares their results with those obtained using coal and biomass pyrolysis in detail. It is controversial whether there are synergistic or additive behaviours when coal and biomass are blended during copyrolysis. In this review, the effects of reaction parameters such as feedstock types, blending ratio, heating rate, temperature, and reactor types on the occurrence of synergy are discussed. Also, the main properties of the copyrolytic products are pointed out. Some possible synergistic mechanisms are also suggested. Additionally, several outlooks based on studies in the literature are also presented in this paper.

Reconstruction of deep wounds in old patients with cutaneous malignant tumor after artificial dermis combined with negative pressure wound therapy / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the effects of artificial dermis combined with negative pressure wound therapy on repairing wound aft er resection of cutaneous malignant tumor in elderly.@*METHODS@#The clinical data of 34 hospitalized patients with cutaneous malignant tumor from July, 2009 to February, 2014 were retrospectively analyzed. The patients received local enlarged excision, artificial dermis covered wounds and 12-16 days of negative pressure wound therapy plus a free skin graft transplant on the surface with an artificial dermis. Recovery and complication aft er operation were assessed.@*RESULTS@#All wounds were restored successfully with good appearance. None severe infection happened.@*CONCLUSION@#Artificial dermis combined with negative pressure wound therapy can repair wound efficiently aft er cutaneous malignant tumor resection was performed for old patients.

Study on the functions of potential new genes of Yersinia pestis type three secretion system / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the functional relations between the putative proteins YpCD1.08, YpCD1.09, YpCD1.16 encoded in pCD1 plasmid of Yersinia pestis and its type III secretion system (T3SS).</p><p><b>METHODS</b>Mutants of YpCD1.08, YpCD1.09, YpCD1.16 were constructed using λ-Red recombinant system. The growth curves of the mutant strains cultivated in TMH medium with or without calcium at 26 °C and 37 °C were determined to analyze the low calcium response phenotype. The transcription levels of ΔYpCD1.08, ΔYpCD1.09, ΔYpCD1.16 in Yersinia pestis and the dependence to temperature were determined using real time RT-PCR after cultivation at 26 °C and 37 °C and extraction of RNA. A β-lactamases reporter system was adopted to study the influence of these genes on the translocation of effector YopE of T3SS.</p><p><b>RESULTS</b>When grown in TMH medium without calcium at 26 °C and 37 °C, the growth curve of the YpCD1.08, YpCD1.09, YpCD1.16 mutants were similar to that of the wild-type strain, indicating that the low calcium response of all the mutants were normal. The ratios of YpCD1.08, YpCD1.09, YpCD1.16 gene transcriptional level at 37 °C and 26 °C were 2.3 ± 0.3, 2.3 ± 0.5 and 3.2 ± 0.7, respectively, indicating that these genes were transcribed in Yersinia pestis and their transcription regulations showed a temperature-dependence that was consistent with the well established temperature-dependent expression of Yersinia T3SS genes. The β-lactamases reporter assays demonstrated that ΔYpCD1.08 could translocate much higher level of YopE into HeLa cells, since that the light intensity ratio of 477/520 nm at 140 min was 2.5, whereas it was 1.8 for the wild-type strain, and the values in ΔYpCD1.09 and ΔYpCD1.16 were similar to the wild-type strain.</p><p><b>CONCLUSION</b>YpCD1.08, YpCD1.09, YpCD1.16 gene are likely to be the new members of T3SS, and the putative protein YpCD1.08 could play some roles in YopE secretion and translocation.</p>

Study on characteristics of printed circuit board liberation and its crushed products.

Recycling printed circuit board waste (PCBW) waste is a hot issue of environmental protection and resource recycling. Mechanical and thermo-chemical methods are two traditional recycling processes for PCBW. In the present research, a two-step crushing process combined with a coarse-crushing step and a fine-pulverizing step was adopted, and then the crushed products were classified into seven different fractions with a standard sieve. The liberation situation and particle shape in different size fractions were observed. Properties of different size fractions, such as heating value, thermogravimetric, proximate, ultimate and chemical analysis were determined. The Rosin-Rammler model was applied to analyze the particle size distribution of crushed material. The results indicated that complete liberation of metals from the PCBW was achieved at a size less than 0.59 mm, but the nonmetal particle in the smaller-than-0.15 mm fraction is liable to aggregate. Copper was the most prominent metal in PCBW and mainly enriched in the 0.42-0.25 mm particle size. The Rosin-Rammler equation adequately fit particle size distribution data of crushed PCBW with a correlation coefficient of 0.9810. The results of heating value and proximate analysis revealed that the PCBW had a low heating value and high ash content. The combustion and pyrolysis process of PCBW was different and there was an obvious oxidation peak of Cu in combustion runs.

Synthesis of carbon nanotubes and porous carbons from printed circuit board waste pyrolysis oil.

The possibility and feasibility of using pyrolysis oil from printed circuit board (PCB) waste as a precursor for advanced carbonaceous materials is presented. The PCB waste was first pyrolyzed in a laboratory scale fixed bed reactor at 600 degrees C to prepare pyrolysis oil. The analysis of pyrolysis oil by gas chromatography-mass spectroscopy indicated that it contained a very high proportion of phenol and phenol derivatives. It was then polymerized in formaldehyde solution to synthesize pyrolysis oil-based resin which was used as a precursor to prepare carbon nanotubes (CNTs) and porous carbons. Scanning electron microscopy and transmission microscopy investigation showed that the resulting CNTs had hollow cores with outer diameter of approximately 338 nm and wall thickness of approximately 86 nm and most of them were filled with metal nanoparticles or nanorods. X-ray diffraction reveals that CNTs have an amorphous structure. Nitrogen adsorption isotherm analysis indicated the prepared porous carbons had a Brunauer-Emmett-Teller surface area of 1214 m(2)/g. The mechanism of the formation of the CNTs and porous carbons was discussed.

A novel reforming method for hydrogen production from biomass steam gasification.

In this work, an experimental study of biomass gasification in different operation conditions has been carried out in an updraft gasifier combined with a porous ceramic reformer. The effects of gasifier temperature, steam to biomass ratio (S/B), and reforming temperature on the gas characteristic parameters were investigated with and without porous ceramic filled in reformer. The results indicated that considerable synergistics effects were observed as the porous ceramic was filled in reformer leading to an increase in the hydrogen production. With the increasing gasifier temperature varying from 800 to 950 degrees C, hydrogen yield increased from 49.97 to 79.91 g H(2)/kg biomass. Steam/biomass ratio of 2.05 seemed to be optimal in all steam-gasification runs. The effect of reforming temperature for water-soluble tar produced in porous ceramic reforming was also investigated, and it was found that the conversion ratio of total organic carbon (TOC) contents is between 71.08% and 75.74%.

Thermogravimetric analysis and kinetic study on large particles of printed circuit board wastes.

Pyrolysis of large printed circuit board (PCB) waste particle was conducted on a specially designed laboratory-scale thermobalance (Macro-TG) with sample loading of 30 g under dynamic nitrogen atmosphere. The effects of heating rate (10, 15, 20 and 25 degrees C min(-1)) and particle size (1 mm x 1 mm, 5 mm x 5 mm, 10 mm x 10 mm and 10 mm x 20 mm) were examined. To compare the different decomposition behavior of fine and large one, the thermal decomposition of PCB waste powder (approximately 5mg) was also performed on a thermogravimetric analyzer (common TG) under various heating rates (10, 15, 20 and 40 degrees C min(-1)) and particle size ranges (0.198-0.165 mm, 0.165-0.074 mm, 0.074-0.055 mm and 0.055-0.047mm). Experimental results show that large particle has a pyrolysis reaction retardancy compared to fine one. The distributed activation energy model was used to study the pyrolysis kinetics. It was found that during pyrolysis process, values of frequency factor (k(0)) changed with different activation energy (E) values. On common TG, the E values range from 156.95 to 319.37 kJ mol(-1) and k(0) values range from 2.67 x 10(13) to 2.24 x 10(27)s(-1). While, on Macro-TG, the range of E was 31.48-41.26 kJ mol(-1) and of the frequency factor was 19.80-202.67s(-1).

Assessment of Bone Quality using Finite Element Analysis Based upon Micro-CT Images

BACKGROUND: To evaluate the feasibility of a micro-image based finite element model to determine the efficacy of sequential treatments on the bone quality in a rat osteoporosis model. METHODS: Rat osteoporosis and treated osteoporosis models were established with the bone loss, restore and maintain concept. Thirty Sprague-Dawley rats were used in this study. A sham operation or ovariectomy was performed at 20 weeks after birth, which was followed by the respective sequential trials as follows: (1) sham-operation only, (2) ovariectomy only, (3) ovariectomized rats with parathyroid hormone maintenance, (4) ovariectomized rats treated with PTH for 5 weeks and then withdrawal, (5) ovariectomized rats treated with PTH for 5 weeks and then with 17 beta-estradiol, and (6) ovariectomized rats treated with parathyroid hormone for 5 weeks and then treated with zoledronate. The histomorphometry indices were determined using the micro-images from a micro-computed tomogram. Finite element analysis was carried out to determine the mechanical properties (Stiffness and Young's modulus) of the vertebra bodies. The differences in properties between the groups were compared using ANOVA and a Bonferroni's multiple group comparison procedure. RESULTS: The histomorphometry and mechanical properties were significantly better in groups (3) and (6) than in the groups (1) and (2) (p < 0.05). The stiffness (sigmas) and Young's modulus (E) was highest in group (3) following by group (6). CONCLUSIONS: Finite element analysis based on micro-images provides a useful tool that reflects the changes in micro-structural and mechanical properties of a rat vertebral body with the bone loss, restore and maintain concept.

Comparison of the Radiologic Results of Total Knee Arthroplasty using Electromagnetic Navigation with the Conventional Technique / 대한정형외과학회잡지

PURPOSE: We wanted to examine the accuracy of the lower limb alignment and implant positioning that was obtained with using the electromagnetic (EM) navigation technique. MATERIALS AND METHODS: We examined 64 patients who underwent 100 TKAs with using EM navigation technique from July 2006 to February 2007. Sixty-two patients who underwent 100 TKAs with using the conventional technique between August 2005 and July 2006 were used as controls. We assessed the mechanical axis and the alpha, beta, gamma and delta angles in the postoperative radiograph of each patient and we compared them among the two groups. RESULTS: The patients in the EM navigation group achieved better accuracy than did the conventional group in terms of the postoperative mean mechanical axis (1.2degrees vs. 2.3degrees). Less variations in the coronal femoral component and the tibial component angle were observed in the navigation group (femur: 89.3degrees vs. 88.7degrees; tibia: 89.6degrees vs. 89.3degrees, respectively), although the difference in the coronal tibial component angle was not significant. CONCLUSION: The use of EM navigation technique in TKA does not always guarantee the precise alignment of the mechanical axis in all planes, as compared to using the conventional technique. Yet it is useful for obtaining better coronal alignment of the femoral component.

The Morphologic Study of the Calcar Femorale and the Femoral Stem in Korean Population

PURPOSE: The aim of this study was to examine morphological data of the calcar femorale using high resolution CT and to determine its relationship with the morphology of femoral stems commonly used in Korea. MATERIALS AND METHODS: CT scans of the bilateral proximal femurs were randomly obtained from 54 Korean subjects(31 males and 23 females). The mean age was 49 years. The length, vertical height and thickness of the calacr femorale were measured. The medial dimension of the proximal portion of the femoral stems was investigated and matched with the distance between the anterior cortex of the proximal femur and the midpoint of the calcar femorale. RESULTS: The calcar femorale was visible in 53 CT scans(98%). The length, vertical height and thickness of the calacr femorale was 11.4+/-3.0 mm, 35.1+/- 5.96 mm and 2.4+/-0.7 mm, respectively, and there were no significant changes with age. The dimensions of the femoral stems were compatible with the morphology around the calcar femorale. CONCLUSION: The calcar femorale is a constant cortical structure that can provide consistent rotational stability for the proposed cementless stems. It is strongly recommended that the calcar femorale be preserved during the femoral preparation.

Changes in gene expression profiles of hydatidiform mole and choriocarcinoma as compared with trophoblast hyperplasia / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the relationship of changes in gene expression profiles of hydatidiform mole and choriocarcinoma with hyperplasia of trophoblasts.</p><p><b>METHODS</b>The differentially expressed genes were analyzed in two pairs of tissues of hydatidiform mole versus normal villi, and in two pairs of normal primary culture trophoblasts versus JAR cell line of chariocarcinoma, using cDNA microarray containing 4096 genes. To confirm the results of cDNA microarray analysis, expressions of some up-regulated genes related to DNA synthesis in normal villi, hydatidiform mole, and 2 choriocarcinoma cell lines (JAR and JEG-3) were examined by immunohistochemistry, immunoblotting and RT-PCR.</p><p><b>RESULTS</b>A total of 89 genes were differentially expressed in all hydatidiform moles, accounting for 2.2% of the genes arrayed. Of the 89 genes, 24 were up-regulated and 65 were down-regulated. Compared with normal primary trophoblasts, there were 433 genes up-regulated and 380 genes down-regulated in JAR cell line. Forty six genes were up-regulated in both hydatidiform mole and choriocarcinoma, while 13 genes were down-regulated. Some genes associated with cell proliferative inhibition were significantly down-regulated, whereas those associated with cell proliferation, malignant transformation, metastasis and drug resistance were highly up-regulated. The expressions of thymidine kinase 1, the small subunit of ribonucleotide reductase (RRM2) were significantly increased in hydatidiform mole, JAR and JEG-3 cells.</p><p><b>CONCLUSION</b>Abnormal expression of genes exists in hydatidiform mole and choriocarcinoma. Hyperplasia of trophoblasts may be related to over-expression of genes coding for synthetic enzymes.</p>

Expression of R2 protein in gestational trophoblastic diseases / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To study the expression of the small subunit ribonucleotide reductase (R2) in gestational trophoblastic diseases (GTD) and to assess its prognostic value.</p><p><b>METHODS</b>The expression of R2 was detected with immunohistochemical method in 15 cases of normal villi, 38 cases of hydatidiform mole (HM), 42 cases of invasive moles (IM) and 18 cases of choriocarcinoma (CC).</p><p><b>RESULTS</b>R2 expression in HM, IM and CC was significantly increased compared with that of normal villi (P=0.000). There were no significant differences in R2 protein expression among HM, IM and CC. Among 38 cases of HM, R2 expression in 8 cases with malignant transformation was significantly higher than in 30 cases of non-malignant transformation mole (P=0.02). Preoperative chemotherapy of gestational trophoblastic tumor including IM and CC did not influence the R2 expression. Compared with patients of stage I (WHO), the R2 protein in gestational trophoblastic tumor (GTT) patients of stage III or stage II was significantly increased (P=0.023 and P=0.038, respectively). The value of R2 in GTT patients with middle or high risk in WHO prognostic scoring system was higher than in the patients with low risk (P=0.018 and P=0.006, respectively).</p><p><b>CONCLUSION</b>R2 expression in GTD is increased, which may be associated with the hyperplasia of trophoblasts, malignant transformation of hydatidiform mole and drug resistance of trophoblastic tumor.</p>