[Emission Characteristics of the Catering Industry in Beijing].

The emissions of the catering industry are important sources of air pollution in megacities in China. A total of 41 restaurants in Beijing were selected as the sampling sites to evaluate the contribution of the catering industry to megacity air pollution. The original emissions load of cooking fume, particulate matter, and non-methane hydrocarbon (NMHC) were studied via field tests for different types of restaurants. The results showed that the cooking fume, particulate matter, and NMHCs generated from the kitchen were 1.93, 6.6, and 10.9 mg·m-3, respectively. An evaluation method based on working days was developed. Considering the total number of restaurants in Beijing, the original emission loads of 2019 were calculated. The cooking fume, particulate matter, and NMHC emissions were 5512, 18849, and 6169 t, respectively. The Pearson numbers of the cooking fume emission and particular matter emission from Sichuan and Hunan cuisine, Roast Duck, Grill and Barbecue, and Chinese Home-Style cuisine were all above 0.6, which indicated a high level of correlation between the cooking fume emission and particular matter emission. Notably, the Pearson numbers of Sichuan and Hunan cuisine and Roast Duck were both higher than 0.8, which indicates a strong correlation between the cooking fume emission and particular matter emission.

[Pollution Characteristics of Cooking Fumes, Particulates, and Non-methane Hydrocarbons in the Exhaust of Typical Beijing Restaurants].

To understand the atmospheric pollution emission concentration and overall emission level of the Beijing catering industry, and thus provide a basis for the targeted formulation of pollution control measures for the catering industry, this study selected typical catering enterprises in Beijing to research. Combined with the use of stoves during the on-site measurement and testing period, the emission concentrations of cooking fumes, particulates, and non-methane hydrocarbons (NMHC), and the relationship between them in different types of catering enterprises, were analyzed, and the emission of atmospheric pollutants in the Beijing catering industry was estimated. The results showed that the average concentrations of cooking fumes, particulates, and NMHC of typical catering enterprises were (2.91±5.52), (9.25±10.02), and (12.72±11.38) mg·m-3, respectively. These all exceed the Beijing local emission standards. Of the typical catering enterprises, roast duck and barbecue had higher particulate matter and NMHC emissions, which easily exceeded the emission standard. Roast duck and barbecue are therefore the governance focus of the catering industry. The ratio of particulates to cooking fumes in roast duck, barbecue, and cooking catering enterprises ranged from 6.21 to 43.08, 5.03 to 19.07, and 0.75 to 7.55, respectively. The emission concentrations of particles are much larger than those of cooking fumes from charcoal grill and fruit-roasted duck. Pearson correlation coefficient analysis showed that the concentrations of particulates and cooking fumes in catering enterprises were strongly correlated, and the concentrations of particulates and NMHC were weakly correlated. The study estimates roughly that the emissions of cooking fumes, particulates, and NMHC were 2492, 6127, and 9436 tons, respectively, from the catering industry in Beijing in 2014.

MODIFIED STOPPA APPROACH FOR PELVIC AND ACETABULAR FRACTURE TREATMENT.

OBJECTIVE: A retrospective review aims to investigate the operative methods and therapeutic effects of the modified Stoppa approach for treating pelvic and acetabular fractures. METHODS: 18 patients with acetabular fracture of the anterior column and pelvic anterior ring fracture underwent surgical treatment using the modified Stoppa approach. Some of the treatment was combined with the iliac fossa approach or rear K-L approach. Fracture reduction and postoperative function were evaluated using the Matta scoring standard and the Majeed scoring system. The Oxford Centre for Evidence-Based Medicine system was used to grade the literature review and create graded B recommendations. RESULTS: Incision length was 6-12 cm (mean, 10 cm), operative duration was 50-150 minutes (mean, 85 minutes), and intraoperative blood loss volume was 400-1,000 ml (mean, 500 ml). 18 patients were followed up for 12-36 months post-operation. In the results of X-ray films, 12 cases were anatomical reductions and the remaining cases were satisfactory reductions. According to Majeed standard, 13 patients were excellent and five patients were good. CONCLUSIONS: Treatment using the modified Stoppa approach was suitable for anterior approaches, in which pelvic and acetabular fractures were sufficiently exposed, the fracture was conveniently reduced, less complications occurred, and curative effect was satisfactory. Level of evidence III, Retrospective comparative study.

OBJETIVO: Uma revisão retrospectiva tem como objetivo investigar os métodos operatórios e efeitos terapêuticos da abordagem modificada de Stoppa para o tratamento de fraturas pélvicas e acetabulares. MÉTODOS: 18 pacientes com fratura acetabular da coluna anterior e fratura do anel anterior pélvico foram submetidos a tratamento cirúrgico utilizando a abordagem de Stoppa modificada. Parte do tratamento foi feita em conjunto com a abordagem da fossa ilíaca ou com a abordagem pelo acesso posterior de K-L. A redução da fratura e a função pós-operatória foram avaliadas pelo padrão de pontuação de Matta e o sistema de pontuação de Majeed. O sistema do Oxford Centre for Evidence-Based Medicine foi usado para classificar a revisão de literatura e criar as recomendações de grau B. RESULTADOS: O comprimento da incisão foi de 6 a 12 cm (média de 10 cm), a duração da cirurgia foi de 50 a 150 minutos (média de 85 minutos) e o volume de perda sanguínea intraoperatória foi de 400 a 1.000 ml (média de 500 ml). 18 pacientes foram acompanhados por 12-36 meses após a operação. Nos resultados dos filmes radiográficos, 12 casos foram de reduções anatômicas e os demais casos foram de reduções satisfatórias. De acordo com o padrão de Majeed, 13 pacientes foram considerados excelentes e cinco pacientes foram considerados bons. CONCLUSÕES: O tratamento que utilizou a abordagem de Stoppa modificada foi adequado para abordagens anteriores, nas quais as fraturas pélvicas e acetabulares estavam suficientemente expostas, a fratura foi convenientemente reduzida, ocorreram menos complicações e o efeito curativo foi satisfatório. Nível de evidencia III, Estudo retrospectivo comparativo.

Modified stoppa approach for pelvic and acetabular fracture treatment / Stoppa modificada para tratamento de fraturas pélvicas e acetabulares

ABSTRACT Objective: A retrospective review aims to investigate the operative methods and therapeutic effects of the modified Stoppa approach for treating pelvic and acetabular fractures. Methods: 18 patients with acetabular fracture of the anterior column and pelvic anterior ring fracture underwent surgical treatment using the modified Stoppa approach. Some of the treatment was combined with the iliac fossa approach or rear K-L approach. Fracture reduction and postoperative function were evaluated using the Matta scoring standard and the Majeed scoring system. The Oxford Centre for Evidence-Based Medicine system was used to grade the literature review and create graded B recommendations. Results: Incision length was 6-12 cm (mean, 10 cm), operative duration was 50-150 minutes (mean, 85 minutes), and intraoperative blood loss volume was 400-1,000 ml (mean, 500 ml). 18 patients were followed up for 12-36 months post-operation. In the results of X-ray films, 12 cases were anatomical reductions and the remaining cases were satisfactory reductions. According to Majeed standard, 13 patients were excellent and five patients were good. Conclusions: Treatment using the modified Stoppa approach was suitable for anterior approaches, in which pelvic and acetabular fractures were sufficiently exposed, the fracture was conveniently reduced, less complications occurred, and curative effect was satisfactory. Level of evidence III, Retrospective comparative study.

RESUMO Objetivo: Uma revisão retrospectiva tem como objetivo investigar os métodos operatórios e efeitos terapêuticos da abordagem modificada de Stoppa para o tratamento de fraturas pélvicas e acetabulares. Métodos: 18 pacientes com fratura acetabular da coluna anterior e fratura do anel anterior pélvico foram submetidos a tratamento cirúrgico utilizando a abordagem de Stoppa modificada. Parte do tratamento foi feita em conjunto com a abordagem da fossa ilíaca ou com a abordagem pelo acesso posterior de K-L. A redução da fratura e a função pós-operatória foram avaliadas pelo padrão de pontuação de Matta e o sistema de pontuação de Majeed. O sistema do Oxford Centre for Evidence-Based Medicine foi usado para classificar a revisão de literatura e criar as recomendações de grau B. Resultados: O comprimento da incisão foi de 6 a 12 cm (média de 10 cm), a duração da cirurgia foi de 50 a 150 minutos (média de 85 minutos) e o volume de perda sanguínea intraoperatória foi de 400 a 1.000 ml (média de 500 ml). 18 pacientes foram acompanhados por 12-36 meses após a operação. Nos resultados dos filmes radiográficos, 12 casos foram de reduções anatômicas e os demais casos foram de reduções satisfatórias. De acordo com o padrão de Majeed, 13 pacientes foram considerados excelentes e cinco pacientes foram considerados bons. Conclusões: O tratamento que utilizou a abordagem de Stoppa modificada foi adequado para abordagens anteriores, nas quais as fraturas pélvicas e acetabulares estavam suficientemente expostas, a fratura foi convenientemente reduzida, ocorreram menos complicações e o efeito curativo foi satisfatório. Nível de evidencia III, Estudo retrospectivo comparativo.

[Atmospheric Pollutant Emission Characteristics from the Cooking Process of Traditional Beijing Roast Duck].

As one of the characteristics of traditional food in Beijing, there is a significant difference between roast duck and other foods in the cooking process, in that fruit trees are used as fuel in the former. However, system research about the emission characteristics of this food source has not been done domestically. In order to grasp such food source emission characteristics and provide technical basis for pollution control, we selected the representative roast duck restaurant in Beijing and studied the emission characteristics of atmospheric pollutants in the cooking process of roast duck. The results showed that the emission concentrations of cooking fumes, particulate matter, volatile organic compounds (VOCs), and aldehyde and ketone compounds were (0.74±0.45), (15.32±7.93), (7.60±3.41), and (1.22±0.59) mg·m-3, respectively. The emission concentration of particulate matter was much higher than that of cooking fumes. The VOC component composition was very complex, containing alkanes, alkenes, aromatic hydrocarbons, and oxygen VOCs, such as aldehydes, ketones, alcohols, ester compounds, and halogenated hydrocarbons, with the highest concentrations of 3-methylfuran, ethanol, and methyl acetate. The main components of aldehyde and ketone compounds were acetaldehyde, formaldehyde, and acrolein, of which C1-C3 compounds were 72.27%.

[Pollution Characteristics of Aldehydes and Ketones Compounds in the Exhaust of Beijing Typical Restaurants].

Aldehydes and ketones compounds, as one of the components in the exhaust of restaurants, are a class of volatile organic compounds (VOCs) with strong chemical reactivity. However, there is no systematic study on aldehydes and ketones compounds in the exhaust of restaurants. To further clarify the food source emission levels of aldehydes and ketones compounds and controlling measures, to access city group catering VOCs emissions control decision-making basis, this study selected 8 Beijing restaurants with different types. The aldehydes and ketones compounds were sampled using DNPH-silica tube, and then ultra performance liquid chromatography was used for quantitative measurement. The aldehydes and ketones concentrations of reference volume condition from 8 restaurants in descending order were Roasted Duck restaurant, Chinese Style Barbecue, Home Dishes, Western Fast-food, School Canteen, Chinese Style Fast-food, Sichuan Cuisine, Huaiyang Cuisine. The results showed that the range of aldehydes and ketones compounds (C1-C9) concentrations of reference volume condition in the exhaust of restaurants was 115.47-1035.99 microg x m(-3). The composition of aldehydes and ketones compounds in the exhaust of sampled restaurants was obviously different. The percentages of C1-C3 were above 40% in the exhaust from Chinese style restaurants. Fast food might emit more C4-C9 aldehydes and ketones compounds. From the current situation of existing aldehydes and ketones compounds control, the removal efficiency of high voltage electrostatic purifiers widely used in Beijing is limited.

[Emission Characteristics of VOCs from Typical Restaurants in Beijing].

Using the EPA method, emission of volatile organic compounds (VOCs) , sampled from barbecue, Chinese and Western fast-food, Sichuan cuisine and Zhejiang cuisine restaurants in Beijing was investigated. VOCs concentrations and components from different cuisines were studied. The results indicated that based on the calibrated baseline ventilation volume, the VOCs emission level from barbecue was the highest, reaching 12.22 mg · m(-3), while those from fast-food of either Chinese or Western, Sichuan cuisine and Zhejiang cuisine were about 4 mg · m(-3). The components of VOCs from barbecue were different from those in the other cuisines, which were mainly propylene, 1-butene, n-butane, etc. The non-barbecue cuisines consisted of high concentration of alcohols, and Western fast-food contained relatively high proportion of aldehydes and ketones organic compounds. According to emission concentration of baseline ventilation volume, barbecue released more pollutants than the non-barbecue cuisines at the same scale. So, barbecue should be supervised and controlled with the top priority.

[Study on the chemical compositions of VOCs emitted by cooking oils based on GC-MS].

Volatile organic compounds (VOCs) are key precursors of ozone and secondary organic aerosols in air, and the differences in the compositions of VOCs lead to their different contribution to atmospheric reaction. Cooking oil fume is one of the important sources of atmospheric VOCs, and its chemical compositions are distinct under different conditions of oil types, food types, cooking methods and heating temperatures etc. In this study, the production of cooking oil fume was simulated by heating typical pure vegetable oils (peanut oil, sunflower oil, soybean oil, olive oil and blend oil) at different temperatures in beakers to investigate the chemical compositions of VOCs. The emitted VOCs were sampled with a Tenax adsorption tube and analyzed using GC-MS after thermal desorption. According to spectral library search and map analysis, using area normalized semi-quantitative method, preliminary qualitative and quantitative tests were conducted for the specific components of VOCs under different conditions.

[Study on the quantitative estimation method for VOCs emission from petrochemical storage tanks based on tanks 4.0.9d model].

VOCs emission from petrochemical storage tanks is one of the important emission sources in the petrochemical industry. In order to find out the VOCs emission amount of petrochemical storage tanks, Tanks 4.0.9d model is utilized to calculate the VOCs emission from different kinds of storage tanks. VOCs emissions from a horizontal tank, a vertical fixed roof tank, an internal floating roof tank and an external floating roof tank were calculated as an example. The consideration of the site meteorological information, the sealing information, the tank content information and unit conversion by using Tanks 4.0.9d model in China was also discussed. Tanks 4.0.9d model can be used to estimate VOCs emissions from petrochemical storage tanks in China as a simple and highly accurate method.

[Preliminary study concerning emissions of the volatile organic compounds from cooking oils].

Cooking oil fume is one of the important sources of atmospheric volatile organic compounds (VOCs), which are the key precursors of ozone and secondary organic aerosols in air. In this study, the production of cooking oil fume was simulated by heating typical pure vegetable oils (peanut oil, sunflower oil, soybean oil, olive oil and blend oil) at different temperatures in beakers to investigate the VOCs emission characteristics. The emitted VOCs were sampled with a Tenax adsorption tube and analyzed using GC-MS after thermal desorption. The results showed that the emission of VOCs increased with the increase of the heating temperature for all the investigated cooking oils, and at a given temperature, the blend oil emitted the lowest amount of VOCs. The VOCs emission intensity at different heating temperatures fitted well with binomial equations and ranged from 1.6-11.1 mg x (kg x min)(-1).