导向喷动流化床生物质快速裂解制液体燃料

在冷模试验得到的优化的结构参数基础上，建立了一套生物质最大处理量为5kg／h的导向管喷动流化床生物质裂解反应器。反应在常压和440～520℃进行，以木屑为生物质原料，二氧化碳和氮气为喷动气或流化气，沙子为流化介质。结果表明该喷动流化床反应器可用于生物质的快速裂解。在400～480℃，液体产率随温度增加而上升，高于480℃时，二次反应的加剧又导致液体产品产率下降。固体和气体的产率则随温度的升高而减少。喷动气和流化气流量的增加均强化了反应器内的传热，并使生物质初始裂解产物的停留时间减少，二次反应进行程度减弱。在适当的裂解条件下液体产率可达73．2％，此时气体和焦的产率分别为12．8％和14．0％。所得液体产品为单一相液体，含水约30％，可用于燃烧。与流化床相比，喷动流化床作为生物质快速裂解反应器可明显提高液体产率。     

一株曲霉果糖转移酶的发酵条件及转果糖基活性

对一株曲霉果糖转移酶菌株的产酶培养条件进行了研究。确定了最佳培养基组成：初始蔗糖质量浓度15～18g／dL，氮源为酵母膏，K2HPO4对果糖转移酶的产生具有明显的促进作用，添加0．2g／dLCMC能够使果糖转移酶活力提高到原来的1．3倍，在pH5．5，30℃条件下，果糖转移酶最高酶活力为30．42U／mL。HPLC分析结果表明，转糖基产物为总质量的55．8％。     

The Use of Brewer’s Spent Grain after Beer Production for Energy Purposes

The aim of this study was to assess the possibilities to use brewer’s spent grains (BSGs) left over from beer production for energy purposes, and to determine its calorific value and chemical composition. The research materials were samples of wet spent grain from a brewery in Poland. Three samples, that are different in ingredient composition, were examined. The examined samples of BSGs were characterised by humidity that is typical for this product (approx. 77–80%). Convective drying of the spent grain contributed to a reduction in the water content in the biomass to below 10%. Samples of dry spent grain that were examined contained a similar amount of ash (3.8–4.1% d.m.) and organic matter (91.0–91.9% d.m.). All the examined spent grain samples demonstrated similar volatile matter content—approx. 77.8–78.7% d.m. and calorific value—approx. 15.6–15.9 MJ/kg. The estimated calorific value for wet samples (approx. 1.4–2.0 MJ/kg) indicated that it is necessary to lower water content in the biomass in order to improve its energy properties.     

腐殖酸类有机肥对当归物质生产及品质的影响

目的:研究成药期追施腐殖酸类有机肥对当归生长、同化基础、干物质积累、产量、品质及感病情况的影响。方法:试验选择3种腐殖酸肥和1种氨基酸液肥,采用1水平随机区组设计,3次重复。结果:追施T1"陕西济农",促进当归地上、地下生长,提高干物质积累,能显著增加当归单根鲜重,增产605kg.hm^-2,醇溶性浸出物含量提高11.31%,综合效果最好。追施T₃"甘肃猛冲"能迅速促进当归地上、地下生长,扩大叶面积及提高地上部干重,肥力显效快,但肥效持续期短,醇溶性浸出物含量提高5.23%。追施T₄"云南生态"后期叶片数较多,叶面积较大,增产565 kg.hm^-2,醇溶性浸出物含量提高3.09%。追施T_-2"甘肃绿能"能显著提高单根鲜重,增产588 kg.hm^-2。结论:追施腐殖酸类有机肥能有效促进成药期当归生长,扩大同化基础,提高叶面积指数,促进干物质积累及向根部转移,有效提高产量和醇溶性浸出物含量。     

Biochar Synthesis from Mineral- and Ash-Rich Waste Biomass,Part 1: Investigation of Thermal Decomposition Mechanism during Slow Pyrolysis

Synthesizing biochar from mineral- and ash-rich waste biomass (MWB), a by-product of human activities in urban areas, can result in renewable and versatile multi-functional materials, which can also cater to the need of solid waste management. Hybridizing biochar with minerals, silicates, and metals is widely investigated to improve parent functionalities. MWB intrinsically possesses such foreign materials. The pyrolysis of such MWB is kinetically complex and requires detailed investigation. Using TGA-FTIR, this study investigates and compares the kinetics and decomposition mechanism during pyrolysis of three types of MWB: (i) mineral-rich banana peduncle (BP), (ii) ash-rich sewage sludge (SS), and (iii) mineral and ash-rich anaerobic digestate (AD). The results show that the pyrolysis of BP, SS, and AD is exothermic, catalyzed by its mineral content, with heat of pyrolysis 5480, 4066, and 1286 kJ/kg, respectively. The pyrolysis favors char formation kinetics mainly releasing CO₂ and H₂O. The secondary tar reactions initiate from ≈318 °C (BP), 481 °C (SS), and 376 °C (AD). Moreover, negative apparent activation energies are intrinsic to their kinetics after 313 °C (BP), 448 °C (SS), and 339 °C (AD). The results can support in tailoring and controlling sustainable biochar synthesis from slow pyrolysis of MWB.     

Computational and Experimental Studies of Selected Types of Biomass Combustion in a Domestic Boiler

The paper analyzes the suitability of four types of biomass pellets as a fuel for heating purposes. Three types of waste biomass (sunflower husks, rapeseed cake, and corn straw) and one type of biomass grown for energy purposes (willow) were selected. After appropriate preparation, the selected starting materials were subjected to the pelletization process. Selected physical and chemical properties of the studied biomass pellets were determined. All four types of the analyzed pellets met the EN-ISO-17225-2:2014 standard in terms of bulk density, dimensions, as well as nitrogen and moisture content. The highest calorific value was pellets made of sunflower husk (17.27 MJ/m³) and willow (16.81 MJ/m³), while the calorific value of pellets made of corn straw and rapeseed cake did not exceed 16.5 MJ/m³ and did not meet the standard. In addition, the ash content for these two types of pellets was well above the standard. A 10 kW domestic biomass boiler was employed for burning the tested pellets. The consumption of analyzed fuels during boiler operation was determined. The concentration of CO, CO₂, and NO_x in exhaust gases was also examined. The obtained experimental results were compared with the numerical calculations with the use of ANSYS Chemkin-Pro using two mechanisms. The highest concentrations of CO₂ and CO were observed during the combustion of sunflower and willow husk pellets, which probably resulted from the highest carbon content and, thus, the highest calorific value when compared to cake and straw pellets. For all analyzed pellets, the value of NO and NO₂ concentration was similar and did not exceed 368 ppm and 18 ppm, respectively. The results closest to the experiment were obtained for calculations using the mechanism developed by Glarborg et al. The research carried out in the article shows that out of the four analyzed types of pellets, only sunflower and willow husk pellets can be burned in a domestic boiler adapted to burning wood pellets, which is a cheap alternative to wood pellets.     

生物质能源开发——Ⅳ.泥炭的催化水解法

以半纤维素含量较高的泥炭为原料,在常压和加压(200℃左右的水蒸汽压)条件下,研究了水解法中反应时间、液固比、反应温度、酸浓度、催化剂等工艺条件对糖化率的影响。并比较了一步法和二步法的转化率。实验结果表明:可用常压一步法水解。其工艺条件为:泥炭粒度100目,反应温度100℃,盐酸浓度1.0～1.5%,液固比10.5～12.0,反应时间80～100min。添加催化剂能提高水解反应速度,FeCl_3有较高的催化活性。在上述条件下有近70%的可水解物水解为还原糖。水解后的残渣可以用于气化。     

钾素影响浙贝母碳同化代谢的研究进展

[目的]总结分析近年来钾素参与浙贝母等植物碳同化代谢的研究进展。[方法]以钾素、浙贝母、碳同化代谢等关键词检索2012年1月至2019年12月中国知网、Web of Science、PubMed、万方、维普等数据库中的文献,总结光合能力与碳同化代谢对植株钾浓度响应的研究概况。[结果]总共采纳29篇相关文献,发现光合作用是影响植物产量的关键因素,不同植物碳同化代谢存在差异。缺钾会导致叶面积减少,二氧化碳转化率和气孔导度降低等;施钾可提高叶绿素含量,增强光合性能等光合能力,增加蔗糖、淀粉等糖类物质含量,同时与之相关的碳代谢相关酶活性和关键酶基因表达情况也会随之变化,如核酮糖-1,5-二磷酸羧化酶、果糖-1,6-二磷酸酶、淀粉酶,以及蔗糖代谢关键酶磷酸蔗糖合成酶和蔗糖合成酶活性均增加,且随着施钾量的逐渐增加呈先上升后下降的趋势,而施钾后酸性转化酶活性降低。[结论]叶片光合能力的反馈抑制是植物生物量累积降低的主要原因,钾素可通过影响叶片碳同化代谢促进光合效应从而提高浙贝母产量。     

Biomass fuel exposure and asthma symptoms among rural school children in Nigeria

Background: Approximately 70% of rural Nigerian households rely on biomass fuels for cooking. The International Study of Asthma and Allergies in Childhood (ISAAC) estimates the prevalence of current wheeze among children in Nigeria to have risen from 10.7% in 1999 to approximately 20% in 2014. Objective: To examine the effects of biomass smoke exposure on asthma symptom prevalence in rural children in Nigeria. Methods: We conducted a cross-sectional survey in rural communities in Nigeria. Asthma symptoms were defined according to ISAAC definitions. Biomass smoke exposure was determined by the types of fuel used for cooking. Logistic regression was used to explore associations between biomass smoke and asthma symptoms. Results: The study population comprised 1,690 school children, of which 865 lived in households cooking with biomass and 825 lived in households not using biomass. Asthma symptoms were reported in 481 (28.5%) children. Biomass fuel was associated with increased odds of asthma symptoms. Adjusted odds ratios (aORs) were 1.38 (95% CI: 1.05–1.80) for nocturnal cough, 1.26 (95% CI: 1.00–1.61) for current wheeze, and 1.33 (95% CI: 1.05–1.69) for report of any asthma-related symptoms. Sex modified the associations between asthma symptoms with biomass fuel: aORs were stronger and significant for males (nocturnal cough = 1.85, 95% CI: 1.24–2.76; current wheeze = 1.48, 95% CI: 1.03–2.13; report of any asthma-related symptoms = 1.60, 95% CI: 1.12–2.28), but weaker and non-significant for females.Conclusion: The risk of asthma symptoms related to biomass smoke exposure appears to differ by sex.     

Long‐Term Exposure to Biomass Fuel and Its Relation to Systolic and Diastolic Biventricular Performance in Addition to Obstructive and Restrictive Lung Diseases

Background: Previous studies have demonstrated an increased risk for cardiovascular events and pulmonary disease in patients with biomass fuel exposure (BFE). However, biventricular heart function has yet to be investigated in these patients. Left ventricular (LV) myocardial performance index (LVMPI), which is an index of global ventricular function, incorporates ejection, isovolumic relaxation, and contraction times. In this study, pulmonary function and biventricular heart function were investigated in nonsmoking female patients with BFE. Methods: Our study population consisted of 46 female patients with BFE (group 1) and 31 control subjects (group 2). Pulmonary function tests and transthoracic echocardiographic examination were performed. Right ventricular myocardial performance index (RVMPI) and LVMPI were obtained by tissue Doppler imaging echocardiography (TDI). Results: BFE caused obstructive and restrictive spirometric impairments. RVMPI was higher in group 1 (0.55 ± 0.07) than group 2 (0.46 ± 0.06) (P = 0.042) and LVMPI was higher in group 1 (0.54 ± 0.08) than group 2 (0.47 ± 0.05) (P = 0.032). Also, pulmonary artery systolic pressure was higher in group 1 than group 2 (P = 0.02). Conclusions: BFE causes both obstructive and/or restrictive lung disease and systolic and diastolic biventricular dysfunction. Nonetheless, long‐term studies are needed to understand on BFE‐related ventricular dysfunctions and to document subsequent cardiovascular events. (Echocardiography 2011;28:52‐61)