Effects of dialysis modality on mortality in patients with end-stage renal disease: A cohort study.

METHODS: Using a retrospective 15-year cohort, stratified by age, this study aimed to analyze the effect of dialysis modality on mortality of ESRD patients in a city of China. Study data were from the medical insurance information system of Kunshan, Jiangsu Province of China, and 1484 patients with ESRD, enrolled from 1 January 2005 to 31 December 2019 were included in this study. The primary outcome event was all-cause mortality, which was calculated in months. Dialysis modalities included hemodialysis (HD) and peritoneal dialysis (PD). Survival analysis and competing-risk regression model were performed in this study. RESULTS: HD costs significantly higher medical expense than the PD treatment regimen. The mean survival time was 121.28 (SE = 3.020) months for HD patients, while that was 94.68 (SE = 3.534) months for the PD. Ten-year survival rates of the young, middle-aged, and elderly were 0.82, 0.56, and 0.26, respectively. For the young (SHR = 0.869, 95% CI: 0.525-1.436) and middle-aged (SHR = 0.715, 95% CI: 0.484-1.057) ESRD patients, different dialysis modalities exhibited no statistical significance on the survival, but for the elderly, HD had a lower risk of mortality than PD (SHR = 0.747, 95% CI: 0.581-0.961). CONCLUSION: Survival of the young and middle-aged ESRD patients was superior to that of the elderly. Considering both survival time and direct medical costs, we recommend that PD could be a better choice for young and middle-aged ESRD patients, while HD may be suitable for older patients.

Neoadjuvant Chemotherapy With CAPOX Versus Chemoradiation for Locally Advanced Rectal Cancer With Uninvolved Mesorectal Fascia (CONVERT): Initial Results of a Phase III Trial.

OBJECTIVE: To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF). BACKGROUND DATA: nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF. METHODS: Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity. RESULTS: Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm ( P =0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm ( P =0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P =0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P =0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis. CONCLUSIONS: nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.

Economic evaluation of three dialysis methods in patients with end-stage renal disease in China.

OBJECTIVES: End-stage renal disease (ESRD) may result in different degrees of physical and psychological pain. Automated peritoneal dialysis (APD), continuous ambulatory peritoneal dialysis (CAPD), and hemodialysis (HD) as the main treatment methods lead to a heavy burden on social economic and family financial. However, there are few studies on the economic evaluation of the three dialysis methods in China. METHODS: Cost-effectiveness analyses were performed using Markov models based on longitudinal data for 15 years of different modalities in Kunshan City, China. Direct cost derived from medical insurance information system, and indirect cost referred to as loss of productivity. Sensitivity analyses were conducted to study uncertainty. RESULTS: The per capita total cost of CAPD was 664,027.00 yuan, the per capita utility is 5.9105. The per capita total cost of APD was 858,800.65 yuan, the per capita utility is 6.4548. The per capita total cost of HD was 1,281,213.64 yuan, the per capita utility is 6.1356. When CAPD was compared with HD, Incremental Cost-Effectiveness Ratio (ICER) was 1,323,389.53 yuan per QALY, compared with APD, ICER was 357,848.13 yuan per QALY. ICER value suggests that APD was cost-effective compared with CAPD and HD at a willingness-to-pay threshold of 538,200 yuan. CONCLUSION: Our research showed that APD is the most appropriate and HD is the worst in terms of cost-effectiveness. However, in fact, HD accounts for a high proportion in China, so some relevant policy suggestions need to be implemented to change the current situation.

Neutralization sensitivity, fusogenicity, and infectivity of Omicron subvariants.

BACKGROUND: The emergence of SARS-CoV-2 Omicron subvariants has raised questions regarding resistance to immunity by natural infection or immunization. We examined the sensitivity of Delta and Omicron subvariants (BA.1, BA.1.1, BA.2, BA.2.12.1, BA.4/5, and BA.3) to neutralizing antibodies from BBIBP-CorV-vaccinated and BBIBP-CorV- or ZF2001-boosted individuals, as well as individuals with Delta and BA.1 breakthrough infections, and determined their fusogenicity and infectivity. METHODS: In this cross-sectional study, serum samples from two doses of BBIBP-CorV-vaccinated individuals 1 (n = 36), 3 (n = 36), and 7 (n = 37) months after the second dose; BBIBP-CorV- (n = 25) or ZF2001-boosted (n = 30) individuals; and fully vaccinated individuals with Delta (n = 30) or BA.1 (n = 26) infection were collected. The serum-neutralizing reactivity and potency of bebtelovimab were assessed against D614G, Delta, and Omicron subvariants (BA.1, BA.1.1, BA.2, BA.2.12.1, BA.4/5, and BA.3) through a pseudovirus neutralization assay. The fusogenicity and infectivity of D614G, Delta, and Omicron subvariants were determined by cell-cell fusion assay and pseudovirus infection assay, respectively. RESULTS: Omicron subvariants markedly escaped vaccine-elicited neutralizing antibodies after two doses of BBIBP-CorV with comparable efficiency. A third dose vaccination of BBIBP-CorV or ZF2001 increased neutralizing antibody titers and breadth against Delta and three Omicron subvariants. Delta and BA.1 breakthrough infections induced comparable neutralizing antibody titers against D614G and Delta variants, whereas BA.1 breakthrough infections elicited a stronger and broader antibody response against three Omicron subvariants than Delta breakthrough infections. BA.2.12.1 and BA.4/5 are more resistant to immunity induced by breakthrough infections. Bebtelovimab had no significant loss of potency against the Delta and Omicron subvariants. Cell culture experiments showed Omicron subvariants to be less fusogenic and have higher infectivity than D614G and Delta with comparable efficiency. CONCLUSIONS: These findings have important public health implications and highlight the importance of repeated exposure to SARS-CoV-2 antigens to broaden the neutralizing antibody response against Omicron subvariants.

Neutralizing immunity against SARS-CoV-2 Omicron BA.1 by infection and vaccination.

The emergence of the SARS-CoV-2 Omicron BA.1 (B.1.1.529) variant has raised questions regarding resistance to neutralizing antibodies elicited by natural infection or immunization. We examined the neutralization activity of sera collected from previously SARS-CoV-2-infected individuals and SARS-CoV-2 naive individuals who received BBIBP-CorV or CoronaVac to BA.1 and the earlier variants Alpha, Beta, and Delta. Both sera from convalescent patients over three months after infection and two-dose BBIBP-CorV or CoronaVac vaccine recipients barely inhibited BA.1, less effectively neutralized Beta and Delta, and moderately neutralized Alpha. However, administering a single dose of BBIBP-CorV or CoronaVac in previously infected individuals or a third dose booster vaccination of BBIBP-CorV or CoronaVac in previously vaccinated individuals enhances neutralizing activity against BA.1 and other variants, albeit with a lower antibody titer for BA.1. Our data suggest that a booster vaccination is important to broaden neutralizing antibody responses against the variants.

Impact of dialysis modality conversion on the health-related quality of life of peritoneal dialysis patients: a retrospective cohort study in China.

BACKGROUND: To analyze the health-related quality of life associated with the conversion of dialysis modality among end-stage renal disease patients in China. METHODS: Patients were recruited from hospitals and a dialysis center in Kunshan, China. Patients converting from continuous ambulatory peritoneal dialysis to automated peritoneal dialysis were recruited as the observation group (n = 64), and patients continuing with continuous ambulatory peritoneal dialysis treatment were included in the control group (n = 64) after matching in this retrospective cohort study. Their health-related quality of life was measured using the kidney disease quality of life instrument in 2019 and 2020, respectively. Baseline socio-demographic characteristics and clinical data were collected in 2019. The before-and-after cross-group comparisons of subscale scores of two groups were conducted using a Student's t-test. Multiple linear regression models were fitted to identify the factors associated with the change of each scale. RESULTS: The health-related quality of life scores of the two groups was comparable in baseline, while the observation group had higher scores in Physical Component Summary (51.92 ± 7.50), Kidney Disease Component Summary (81.21 ± 8.41), Symptoms (90.76 ± 6.30), Effects (82.86 ± 11.42), and Burden (69.04 ± 15.69) subscales after one year. In multivariate regression analysis, the change of Physical Component Summary was significantly associated with conversion to APD (ß = 11.54, 95% CI [7.26-15.82]); the change of Mental Component Summary with higher education (ß =  - 5.96, 95% CI [-10.18--1.74]) and CCI (>2) (ß = 5.39, 95% CI [1.05-9.73]); the change of Kidney Disease Component Summary with conversion to APD (ß = 15.95, 95% CI [10.19-21.7]) and age (>60 years) (ß =  - 7.36, 95% CI [-14.11--0.61]); the change of Symptoms with CCI (>2) (ß = 7.96, 95% CI [1.49-14.44]); the change of Effects with conversion to APD (ß = 19.23, 95% CI [11.57-26.88]); and the change of Burden with conversion to APD (ß = 22.40, 95% CI [13.46-31.34]), age (>60 years) (ß =  - 12.12, 95% CI [-22.59--1.65]), and higher education (ß =  - 10.38, 95% CI [-19.79--0.98]). CONCLUSIONS: The conversion of dialysis modality had a significant impact on the scores of most subscales. Patients converting from continuous ambulatory peritoneal dialysis to automated peritoneal dialysis generally had improved health-related quality of life scores.

Research advances on the clinical characteristics and diagnosis and treatment of autoimmune disease-related ulcers / 中华烧伤杂志

Studies have shown that autoimmune disease (AID)-related ulcers are disease complications that lead to serious poor prognosis such as infection and disability. It is difficult to make a clear diagnosis and there are contradictions between the applications of immunosuppressive therapy and anti-infectious therapy. Improper diagnosis and immunosuppressive therapy can easily delay the timing of anti-infectious therapy and surgery for patients, which bring adverse effects on the prognosis of patients. This paper reviews the concept, clinical characteristics and treatment suggestions of each subtype of AID-related ulcers, in order to provide more ideas for AID-related ulcers' clinical diagnosis and treatment.

Persistence of Antibody and Cellular Immune Responses in Coronavirus Disease 2019 Patients Over Nine Months After Infection.

BACKGROUND: The duration of humoral and T and B cell response after the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains unclear. METHODS: We performed a cross-sectional study to assess the virus-specific antibody and memory T and B cell responses in coronavirus disease 2019 (COVID-19) patients up to 343 days after infection. Neutralizing antibodies and antibodies against the receptor-binding domain, spike, and nucleoprotein of SARS-CoV-2 were measured. Virus-specific memory T and B cell responses were analyzed. RESULTS: We enrolled 59 patients with COVID-19, including 38 moderate, 16 mild, and 5 asymptomatic patients; 31 (52.5%) were men and 28 (47.5%) were women. The median age was 41 years (interquartile range, 30-55). The median day from symptom onset to enrollment was 317 days (range 257 to 343 days). We found that approximately 90% of patients still have detectable immunoglobulin (Ig)G antibodies against spike and nucleocapsid proteins and neutralizing antibodies against pseudovirus, whereas ~60% of patients had detectable IgG antibodies against receptor-binding domain and surrogate virus-neutralizing antibodies. The SARS-CoV-2-specific IgG+ memory B cell and interferon-γ-secreting T cell responses were detectable in more than 70% of patients. CONCLUSIONS: Severe acute respiratory syndrome coronavirus 2-specific immune memory response persists in most patients approximately 1 year after infection, which provides a promising sign for prevention from reinfection and vaccination strategy.

High-speed 3D digital image correlation for rolling deformation of a tire sidewall and measuring dynamic contact patch length.

Tires play a vital role in a vehicle's operational stability, comfort, and security. However, due to the influence of test equipment and tire operating conditions, the perception of rolling tire characteristics is still in the stage of gradual improvement, especially the analysis of sidewall rolling deformation and dynamic contact peculiarities of tires/road interactions, which has restricted the analysis of rolling energy dissipation and the accurate observation of tire forces. In this paper, the high-speed stereo-vision system was created by high-speed cameras, and the relative rigid and flexible displacement, strain, and trajectory trend of marker points and the real-time global displacement field of the sidewall during the tire-rolling cycle were acquired utilizing the improved digital image correlation algorithm under different rolling velocities. Meanwhile, the periodic dissipation of the strain concentration region was observed, and the phenomenon of strain resonance appeared at the overlap of the periods. The relative flexibility strain and shear strain of the marker point were obtained on the plane element, which resulted in the relative flexibility major principle strain of the plane element, and then it achieved recognition of the leading and trailing points of the contact patch and the accurate measurement of dynamic contact patch length.

Health-related quality of life in older Chinese patients with diabetes.

BACKGROUND: Although older diabetes patients with unique characteristics should be cared carefully to improve their health-related quality of life (HRQOL), the association between diabetes and HRQOL remain unclear, especially in Asians. We aimed to compare the HRQOL between older Chinese patients with type 2 diabetes (T2D) and their age-gender-matched controls. METHODS: Older patients with T2D were recruited from a community hospital in Suzhou located in the east part of China while controls were selected from a community-based health survey of older adults aged 60 years or older. HRQOL of cases and controls was assessed by the EQ-5D-3L. The impact of T2D on HRQOL was investigated using a liner regression model and the relationship between T2D and EQ-5D health problems was evaluated using logistic regression models. RESULTS: A total of 220 cases and 440 controls were included. The mean age of the participants was 68.8 years and women accounted for 69.1% of the study sample. The EQ-5D-3L index score was lower for older people with T2D (0.886) than their controls (0.955). After multivariable adjustment, the difference in ED-5D-3L index score between older people with and without T2D was 0.072. In logistic regression analyses, T2D was positively associated with reporting of problems in mobility (odds ratio [OR] = 5.00); pain/discomfort (OR = 1.66), and anxiety/depression (OR = 3.2). CONCLUSIONS: T2D has a detrimental effect on HRQOL of older Chinese people.

Peptide Bond Synthesis by a Mechanism Involving an Enzymatic Reaction and a Subsequent Chemical Reaction.

We recently reported that an amide bond is unexpectedly formed by an acyl-CoA synthetase (which catalyzes the formation of a carbon-sulfur bond) when a suitable acid and l-cysteine are used as substrates. DltA, which is homologous to the adenylation domain of nonribosomal peptide synthetase, belongs to the same superfamily of adenylate-forming enzymes, which includes many kinds of enzymes, including the acyl-CoA synthetases. Here, we demonstrate that DltA synthesizes not only N-(d-alanyl)-l-cysteine (a dipeptide) but also various oligopeptides. We propose that this enzyme catalyzes peptide synthesis by the following unprecedented mechanism: (i) the formation of S-acyl-l-cysteine as an intermediate via its "enzymatic activity" and (ii) subsequent "chemical" S → N acyl transfer in the intermediate, resulting in peptide formation. Step ii is identical to the corresponding reaction in native chemical ligation, a method of chemical peptide synthesis, whereas step i is not. To the best of our knowledge, our discovery of this peptide synthesis mechanism involving an enzymatic reaction and a subsequent chemical reaction is the first such one to be reported. This new process yields peptides without the use of a thioesterified fragment, which is required in native chemical ligation. Together with these findings, the same mechanism-dependent formation of N-acyl compounds by other members of the above-mentioned superfamily demonstrated that all members most likely form peptide/amide compounds by using this novel mechanism. Each member enzyme acts on a specific substrate; thus, not only the corresponding peptides but also new types of amide compounds can be formed.

A time series analysis on under 5 mortality rate in Zhejiang Province / 预防医学

Objective To study the temporal distribution regular pattern of under 5 mortality rate(U5MR)from 1 998 to 201 4 in Zhejiang Province,and to predict the under 5 mortality rate in 201 5.Methods A time series ARIMA (p,d,q) forecasting model for U5MR was conducted using IBM SPSS Statistics 20.0 statistical analysis software.Results The UMAR showed downward trend.The ARIMA(2,1 ,2)model of U5MR from 1 998 to 201 4 in Zhejiang Province is yt =-0.696 +0.636yt -1 +0.024yt -2 +0.340yt -3 +αt -0.003αt -1 +0.997αt -2 ,and the model fitting was good.Each of the actual mortality was consistent with the trend of model prediction,and was within the 95% confidence interval.The predicted value of U5MR was 4.08‰ (95% CI:1 .52‰ -6.64‰)in 201 5.Conclusion Time series analysis is an effective way to analyze the temporal distribution regular pattern of U5MR,which could be used for short -term prediction.

[Analysis on Mechanism of Rainout Carried by Wet Stack of Thermal Power Plant].

Rainout from wet-stack took placed in many thermal power plants with WFGD system. Research on causes of the rainout is important to solve the problem. The objective of this research is to analyze the mechanism of rainout. Field study was performed to collect experimental data in one thermal power plant, including the amount of desulfurization slurry carried by wet flue gas, liquor condensate from wet duct, and droplets from the wet stack. Source apportionment analysis was carried out based on physical and chemical data of liquid sample and solid sample. The result showed that mist eliminator operated well, which met the performance guarantee value. But the total amount of desulfurization slurry in flue gas and the sulfate concentration in liquid condensate discharge from the wet duct/stack increased. The liquid condensate accumulated in the wet duct/stack led to liquid re-entrainment. In conclusion, the rainout in this power plant was caused by the short of wet ductwork or liquid discharge system, the droplets caused by re-entrainment carried by the saturated gas released from the stack. The main undissolved components of the rainout were composite carbonate and aluminosilicate. Although ash concentration in this WFGD met the regulation criteria, source apportionment analysis showed that fly ash contributed to rainout was accounted for 60%. This percentage value was same as the data of solid particles in the condensate. It is important to optimize the wet ductwork, wet stack liner, liquid collectors and drainage. Avoiding the accumulation from saturated vapor thermal condensation is an effective way to solve the wet stack rainout.

[Study on the association between diet, nutrient and attention deficit hyperactivity disorder among children in Shanghai, Kunshan, Wuxi three kindergarten].

OBJECTIVE: To explore the correlation between nutrition and children with attention deficit hyperactivity disorder (ADHD). METHODS: For 417 students from Shanghai and Jiangsu Province, Conners Parent Symptom Questionnaire was used to investigate learning disorders and Food Frequency Questionnaire was used to evaluate the dietary and nutrient intake. Correlation between ADHD and Diet was analyzed. RESULTS: The rate of the ADHD abnormalities was 3.2%, there was no statistical difference between both the various regions and the genders. Partial correlation analysis showed that there was a positive correlation between diet intake (processed meat, salty snacks) and hyperactivity index (P < 0.05); A negative correlation was found between vegetables, coarse cereals, aquatic products, beef, mutton, milk and hyperactivity index (P < 0.05). The regression showed that there was a negative correlation between calcium and hyperactivity index (P < 0.05). CONCLUSION: Children's diet pattern is an important environmental impact foctor for ADHD.

Changes of expression levels of NK,NKT cells and their receptors in peripheral blood of human and its correlation with rheumatoid arthritis / 中国免疫学杂志

Objective:To explore the changes of NK and NKT cells and the expression levels of their activated, inhibitory receptors in the peripheral blood of patients with newly diagnosed rheumatoid arthritis ( RA), and to reveal the potiential role of NK and NKT cells played in the pathogenesis of RA.Methods:32 patients with new onset RA and 15 healthy controls were recruited.Activated and inhibitory NK and NKT cells in peripheral blood were quantified by flow cytometry.The frequency of spontaneous and stimulated IFN-γ+NK and NKT cells and CD107aγ+NK cells were examined.Finally,the potential relationship between the frequency of NK and NKT cells subsets and clinical indexes were analyzed.Results:The frequencies of NK cells in peripheral blood in RA patients were sig-nificantly lower than those in the controls ( P=0.026 ).The frequencies of NKG2D+, NKP46+activated NK cells and NKG2C+, NKG2D+,NKP46+activated NKT cells in RA patients were significantly higher than those in the controls (P=0.011,P=0.010,and P<0.001,P=0.032,P=0.001,respectively),whereas the frequencies of KIR2DL3+,KIR3DL1+and NKG2A+inhibitory NK cells and KIR2DL3+,NKG2A+inhibitory NKT cells in RA patients were significantly lower (P=0.002,P=0.002,P=0.014,and P=0.027,P=0.002,respectively).Moreover, the frequencies of stimulated IFN-γ+NK cells and IFN-γ+NKT cells, spontaneous and stimulated CD107 aγ+NK cells in RA patients were significantly higher than that in the controls ( P=0.037, P=0.004 and P=0.001, P=0.001, respectively).Furthermore,the frequencies of NK cells,NKG2Aγ+and KIR2DL3γ+inhibitory NK cells were correlated significantly with the values of DAS28 in RA patients (r=0.357,P=0.045;r=0.399,P=0.024;r=0.468,P=0.021,respectively).Conclusion:Lower frequencies of NK cells, higher frequencies of activated NK cells and activated NKT cells, lower frequencies of inhibitory NK cells and inhibitory NKT cells, and higher NK cell activity may induce the autoimmune reaction involved in the pathogenesis of RA.

[Surgical treatment of Siewert II adenocarcinoma of the esophagogastric junction].

OBJECTIVE: To explore the outcomes after surgical treatment of esophagogastric junction carcinoma (EGJC). METHODS: One hundred and eighty-five patients with EGJC undergoing surgery from October 2000 to September 2006 at the Cancer Hospital of Shantou University were reviewed retrospectively. The clinical outcomes were compared between transthoracic and transabdominal approach. RESULTS: Of the 185 patients, 133 underwent operation via transthoracic approach and 52 via transabdominal approach. The postoperative complication rates were 10.5%(14/133) and 11.5%(6/52) and the 1-, 3-, 5-year overall survival rates were 83.9%, 44.5%, 32.9% and 86.0%, 38.0%, 30.0% in transthoracic and transabdominal groups respectively, and the difference were not statistically significant (both P>0.05). CONCLUSION: Surgical approach should be individualized for EGCJ.

Fate of hazardous air pollutants in oxygen-fired coal combustion with different flue gas recycling.

Experiments were performed to characterize transformation and speciation of hazardous air pollutants (HAPs), including SO(2)/SO(3), NO(x), HCl, particulate matter, mercury, and other trace elements in oxygen-firing bituminous coal with recirculation flue gas (RFG) from 1) an electrostatic precipitator outlet or 2) a wet scrubber outlet. The experimental results showed that oxycombustion with RFG generated a flue gas with less volume and containing HAPs at higher levels, while the actual emissions of HAPs per unit of energy produced were much less than that of air-blown combustion. NO(x) reduction was achieved in oxycombustion because of the elimination of nitrogen and the destruction of NO in the RFG. The elevated SO(2)/SO(3) in flue gas improved sulfur self-retention. SO(3) vapor could reach its dew point in the flue gas with high moisture, which limits the amount of SO(3) vapor in flue gas and possibly induces material corrosion. Most nonvolatile trace elements were less enriched in fly ash in oxycombustion than air-firing because of lower oxycombustion temperatures occurring in the present study. Meanwhile, Hg and Se were found to be enriched on submicrometer fly ash at higher levels in oxy-firing than in air-blown combustion.

Measurement and capture of fine and ultrafine particles from a pilot-scale pulverized coal combustor with an electrostatic precipitator.

Experiments were carried out in a pilot-scale pulverized coal combustor at the Energy and Environmental Research Center (EERC) burning a Powder River Basin (PRB) subbituminous coal. A scanning mobility particle sizer (SMPS) and an electrical low-pressure impactor (ELPI) were used to measure the particle size distributions (PSDs) in the range of 17 nm to 10 microm at the inlet and outlet of the electrostatic precipitator (ESP). At the ESP inlet, a high number concentration of ultrafine particles was found, with the peak at approximately 75 nm. A trimodal PSD for mass concentration was observed with the modes at approximately 80-100 nm, 1-2 microm, and 10 microm. The penetration of ultrafine particles through the ESP increased dramatically as particle size decreased below 70 nm, attributable to insufficient or partial charging of the ultrafine particles. Injection of nanostructured fine-particle sorbents for capture of toxic metals in the flue gas caused high penetration of the ultrafine particles through the ESP. The conventional ESP was modified to enhance charging using soft X-ray irradiation. A slipstream of flue gas was introduced from the pilot-scale facility and passed through this modified ESP. Enhancement of particle capture was observed with the soft X-ray irradiation when moderate voltages were used in the ESP, indicating more efficient charging of fine particles.

Energy Recycling by Co-Combustion of Coal and Recovered Paint Solids from Automobile Paint Operations.

Experiments were carried out in a pilot-scale pulverized coal combustor at the Energy and Environmental Research Center (EERC) burning a Powder River Basin (PRB) subbituminous coal. A scanning mobility particle sizer (SMPS) and an electrical low-pressure impactor (ELPI) were used to measure the particle size distributions (PSDs) in the range of 17 nm to 10 µm at the inlet and outlet of the electrostatic precipitator (ESP). At the ESP inlet, a high number concentration of ultrafine particles was found, with the peak at approximately 75 nm. A trimodal PSD for mass concentration was observed with the modes at approximately 80-100 nm, 1-2 µm, and 10 µm. The penetration of ultrafine particles through the ESP increased dramatically as particle size decreased below 70 nm, attributable to insufficient or partial charging of the ultrafine particles. Injection of nanostructured fine-particle sorbents for capture of toxic metals in the flue gas caused high penetration of the ultrafine particles through the ESP. The conventional ESP was modified to enhance charging using soft X-ray irradiation. A slipstream of flue gas was introduced from the pilot-scale facility and passed through this modified ESP. Enhancement of particle capture was observed with the soft X-ray irradiation when moderate voltages were used in the ESP, indicating more efficient charging of fine particles.