Variation of White Spruce Carbon Content with Age, Height, Social Classes and Silvicultural Management

The accuracy and precision with which carbon amounts have been accounted for in forests have been questioned. As countries seek to comply with agreements to reduce global warming and industries seek to maximize bioenergy potential, this matter has increased international concern. White spruce (Picea glauca (Moench) Voss) stand density management trials in the Petawawa Research Forest, Ontario, Canada, were sampled to evaluate carbon concentration variation within trees and plots of differing stand density. Sample-drying methodologies were also tested to compare freeze-dried carbon (FDC) and oven-dried carbon (ODC) measurements. The average FDC was 51.80 ± 1.19%, and the corrected freeze-dried carbon content (FDCCOR) was 51.76 ± 1.33%. The average ODC was 49.10 ± 0.92%, and the average volatile carbon fraction (Cvol) was 2.67 ± 1.71%. FDC was higher than ODC (mean of the differences = 2.52) and generally more variable. ODC significantly decreased radially and longitudinally. FDC was significantly affected by thinning, where heavy treatments resulted in the highest FDC amounts compared to medium, light, and control treatments. In addition to reducing carbon content (CC), drying influences wood CC in many ways that are still to be elucidated. The results of this study suggest that ODC should continue to be used within the bioenergy industry, while FDC must become the preferred standard for carbon accounting protocols.

Towards quality charcoal briquettes

Исследовались характеристики и свойства древесно-угольных брикетов, используемых для кальянокурения, влияющие на их эксплуатационные возможности. Проведён сравнительный анализ древесно-угольных брикетов из кокосового, берёзового и соснового сырья. Кокосовый уголь является дорогостоящим сырьём. Предложено заменить кокосовый уголь на берёзовый, что экономически целесообразно. Для получения образцов угля проведён пиролиз кокоса, берёзы и сосны. Полученные образцы в дальнейшем исследовались методами ТГА и ДТГ. Определялись влажность, зольность, содержание нелетучего углерода. Проведено исследование, моделирующее рабочее состояние брикета, что позволило определить важнейшие характеристики древесно-угольного брикета используемого для кальянокурения. Выявлено, что основными эксплуатационными характеристиками являются: запах и прочность брикета в рабочем состоянии, характер разрушения при интенсивном воздействии воздухом. Определено влияние на качество брикетов следующих факторов: сырьё для угля, фракционный состав угля, тип связующего, количество связующего, давление прессования. Полученные брикеты из берёзового угля не уступают кокосовым брикетам по ряду характеристик, что позволяет снизить затраты на изготовление древесно-угольных брикетов при использовании берёзового сырья вместо кокосового. Выявлена перспектива использования берёзового угля в качестве замены кокосовому, а также предложена формула получения конечного продукта. The work investigated the characteristics and properties that affect the operational capabilities of charcoal briquettes used for hookah smoking. A comparative analysis of charcoal briquettes from coconut, birch and pine raw materials. The main raw material for the production of hookah briquettes is coconut coal, which is an expensive raw material. The paper proposes to replace coconut coal with birch, which is economically feasible. To obtain coal samples, pyrolysis of coconut, birch and pine was carried out. The obtained samples were further investigated by the TGA and DTG methods, moisture, ash, and non-volatile carbon content were determined. A study simulating the working condition of the briquette was carried out, which made it possible to determine the most important characteristics of the charcoal briquette used for hookah smoking. It is revealed that the main operational characteristics are: the smell and durability of the briquette in working condition, the nature of the destruction under intense exposure to air. The influence of the following factors on the quality of briquettes was determined: raw materials for coal, fractional composition of coal, type of binder, amount of binder, pressing pressure. The obtained birch charcoal briquettes are not inferior to coconut briquettes in a number of characteristics, which allows to reduce the cost of producing charcoal briquettes when using birch raw materials instead of coconut. The prospect of using birch coal as a substitute for coconut coal is revealed, and a formula for obtaining the final product is also proposed.

BIOMETHANE POTENTIAL OF INVASIVE AQUATIC WEED WATER PRIMROSE

This study aims to examine the perspective of feedstock for producing biomethane from invasive aquatic weed water primroses (Ludwigia Hyssopifolia). The methane yield and methane content of biogas were analyzed and studied. The calculating methods of theoretical methane yield based on the elemental application or the theoretical chemical oxygen demand (COD) number were showed. The percentage of element chemicals, carbon (C), hydrogen (H), oxygen (O), nitrogen (N), and sulfur (S) of raw materials were analyzed, and results were 40.2%, 5.03%, 22.13%, 1.8% and 0.24%, respectively. The plant biomass was contained moisture content, volatile carbon, fixed carbon and ash were 7.28%, 63.07%, 1.28% and 28.37%, respectively. From the water primroses calculated yield of methane (CH4), carbon dioxide (CO2) and ammonia (NH3) results were 54.90%, 41.40% and 3.70%, respectively. Therefore, the aquatic weed water primroses biomass are suitable feedstock for biogas production as well as future scale-up studies.

Carbon Dioxide (CO2) Capture in Alkanolamines Impregnated Activated Carbon Developed from Date Stones

The concern to reduce global carbon emissions has significantly improved the development of efficient solid sorbents such as activated carbon (AC). In this study, AC is developed from date stones which is one of the abundantly found agricultural waste material in gulf region. The AC was completely characterized in terms of pore volume, surface area, stability test, volatile carbon and fixed carbon contents. Impregnation of AC was performed by three different alkanolamines, namely Diethylene triamine (DETA), Pentaethylene hexamine (PEHA) and Di-ethanol amine (DEA). The alkanolamine impregnated sorbents were utilized for CO2adsorption at temperatures of 25, 30, 40, 50, 60, 70 and 100 °C and carbon dioxide (CO2) concentrations of 10, 30, 50, 70 and 92% in helium. The adsorption phenomenon was evaluated by Langmuir isotherms for all the studied adsorbents. The AC developed from date stones provided high adsorption loading capacity of CO2 i.e., 89.79 mg/g of AC at 25 °C. Thermodynamic parameters showed that the adsorption was endothermic and spontaneous in nature. Moreover, desorption profiles reveal that DETA-AC samples provided most favorable characteristics with respect to the value of desorption constant.

Pyrolysis of ripe and thin aspen Wood

Изучен процесс пиролиза спелой и тонкомерной осиновой древесины в диапазоне конечной темпе- ратуры пиролиза 400–700 °С. Определены зависимости выхода древесного угля (ДУ) от температуры продолжительности пиролиза. Получены уравнения регрессии для основных показателей качества ДУ из осины, таких как содержание нелетучего углерода, суммарный объем пор, кажущаяся плотность и активность по йоду. Показано, что ДУ, полученный из спелой осиновой древесины при температуре не менее 600 °С, имеет сформированную углеродную матрицу и вполне пригоден для получения актив- ных углей. The process of ripe and thin aspen wood pyrolysis in the range of the final pyrolysis temperature of 400–700 °С is studied. The dependences of the charcoal yield on the temperature and duration of pyrolysis are determined. Regression equations for the main indicators of the aspen charcoal quality, such as content of non-volatile carbon, total pore volume, apparent density, and iodine activity are obtained. It is shown that the charcoal obtained from ripe aspen wood at a temperature of at least 600 °С has a formed carbon matrix and is quite suitable for the produc- tion of active carbons.

Synergistic Coding of Human Odorants in the Mosquito Brain

The yellow fever mosquito Aedes aegypti employs olfaction to locate humans. We applied CRISPR-Cas9 genome engineering and neural activity mapping to define the molecular and cellular logic of how the mosquito brain is wired to detect human odorants. We determined that the breath volatile carbon dioxide (CO2) is detected by the largest unit of olfactory coding in the primary olfactory processing center of the mosquito brain, the antennal lobe. Synergistically, CO2 detection gates synaptic transmission from defined populations of olfactory sensory neurons, innervating unique antennal lobe regions tuned to the human sweat odorant L-(+)-lactic acid. Our data suggests that simultaneous detection of signature human volatiles rapidly disinhibits a multimodal olfactory network for hunting humans in the mosquito brain.

Evidence of Enhanced Ionization During Early Planet Formation

<p>There is growing observational evidence that giant planet formation happens early, within a million years of the coalescence of the protoplanetary disk. Ionization rate is one of the most important parameters controlling both the chemical and dynamical processes in these disks. What few observational constrains on ionization currently exists suggest overall low ionization, limiting the processes able to take place. This is seemingly in conflict with chemical models which demonstrate the importance of ionization for the chemical processing of volatile carbon and observations which suggest such processing is ubiquitous and happens quickly. I will present new NOEMA observations which, when combined with chemical modeling, are indicative of enhanced ionization rates in the envelopes of three Class I protostars.  I will then discuss the potential impact of this early enhancement on the chemical composition of the material available to forming planets.</p>