Analysis of Volatile Components of Jasmine and Jasmine Tea during Scenting Process

Jasmine tea is widely loved by the public because of its unique and pleasant aroma and taste. The new scenting process is different from the traditional scenting process, because the new scenting process has a thin pile height to reduce the high temperature and prolong the scenting time. We qualified and quantified volatiles in jasmine and jasmine tea during the scenting process by gas chromatography-mass spectrometry (GC-MS) with a headspace solid-phase microextraction (HS-SPME). There were 71 and 78 effective volatiles in jasmine and jasmine tea, respectively, including 24 terpenes, 9 alcohols, 24 esters, 6 hydrocarbons, 1 ketone, 3 aldehydes, 2 nitrogen compounds, and 2 oxygen-containing compounds in jasmine; 29 terpenes, 6 alcohols, 28 esters, 8 nitrogen compounds, 1 aldehyde, and 6 other compounds in jasmine tea. The amounts of terpenes, esters, alcohols, nitrogen compounds, and hydrocarbons in jasmine and tea rose and then fell. The amount of oxygenated compounds of tea in the new scenting process first rose and then fell, while it showed a continuous upward trend during the traditional process. The amount of volatiles in jasmine and tea produced by the new scenting process were higher than that of the traditional scenting process at the same time. This study indicated that jasmine tea produced by the new scenting process had better volatile quality, which can provide proof for the new scenting process.

Analysis of biological methods for quarry wastewater treatment from nitrogen compounds

Деятельность горнодобывающих предприятий неотрывно сопряжена с ведением взрывных работ. В настоящее время наиболее распространенными взрывчатыми веществами являются эмульсионные взрывчатые вещества, граммониты, амоналы, аммониты и другие взрывчатые вещества, содержащие нитрат аммония, который в процессе взрывания переходит в сточные воды в форме нитрат- и нитрит-ионов, а также ионов аммония. Превышение предельно допустимой концентрации азотных соединений в водных объектах может приводить к эвтрофикации. В результате данного процесса происходит нарушение экологического баланса водоемов, а именно увеличение численности различных гидробионтов, уменьшение прозрачности воды и содержания растворенного кислорода. Помимо этого в водоемах осуществляется преобразование нитратной формы азота в нитритную, которая негативно воздействует на нервную и сердечно-сосудистую системы человека при употреблении воды из такого водоема. На данный момент существуют физико-химические, химические и биологические методы очистки вод от азотных соединений. Использование каждого из перечисленных методов обуславливается параметрами карьерных сточных вод и требованиями, предъявляемыми к качеству очистки. Цель работы. Целью работы является обзор методов биологической очистки, которые могут применяться для удаления соединений азота из карьерных сточных вод, а также определение наиболее перспективного метода при условии большого объема образования карьерных сточных вод. Методы исследования. Методы исследования включают в себя анализ и сравнение биологических методов очистки, которые могут использоваться для удаления азотных соединений из образующихся сточных вод в карьере. Результаты работы. Рассмотрены различные виды процессов и систем, включая процесс нитрификации и денитрификации, Anammox-процесс, фито-очистные системы, биоплато, биопруды и системы микроводорослей. Приведены факторы, влияющие на эффективность работы данных процессов и систем, а также дана сравнительная характеристика с выделением достоинств и недостатков каждого из них. Наиболее предпочтительным методом биологической очистки большого объема образующихся карьерных сточных вод признан метод комплексной очистки по типу constructedwetlands с комплексным применением видов высшей и низшей растительности. The activities of mining enterprises are inextricably linked with the conduct of blasting operations. Currently, the most common explosives are emulsion explosives, grammonites, amons, ammonites and other explosives containing ammonium nitrate, which, during the blasting process, passes into wastewater in the form of nitrate and nitrite ions, as well as ammonium ions. Exceeding the maximum permissible concentration of nitrogen compounds in water bodies can lead to eutrophication. As a result of this process, there is a violation of the ecological balance of reservoirs, as well as an increase in the number of various hydrobionts, a decrease in the transparency of water and the content of dissolved oxygen. In addition, the nitrate form of nitrogen is converted into nitrite in reservoirs, which negatively affects the nervous and cardiovascular system of a person when drinking water from such a reservoir. At the moment, there are physico-chemical, chemical and biological methods of water treatment from nitrogen. The use of each of these methods is determined by parameters of quarry wastewater and the requirements for treatment quality. Aim. The aim of the work is to review the methods of biological purification that are used for nitrogen compounds from quarry wastewater. Methods. The research methods include the analysis and comparison of biological treatment methods. Results. The factors affecting the efficiency of these processes and systems are presented, as well as these comparative characteristics, highlighting the advantages and disadvantages of each of them. The most preferred biological treatment method of a large volume of formed quarry wastewater is the recognized methods of complex treatment according to the type of constructed wetlands with the complex use of higher and lower plant species.

New rout for synthesizing triammonium citrate crystal with unique crystallography and its application in synthesizing nitrogen doped graphene quantum dot

Triammonium citrate crystal (TAC) has many applications in food, pharmaceutical, agricultural and other industries. In this work, TAC crystals were synthesized using a new method and with the least use of materials and tools. This crystal has a unique structure and special and new angles and bonds that were identified by crystallography. This crystal was then used to synthesize nitrogen- doped graphene quantum dot (N-GQD) with hydrothermal method. Synthesized N-GQD has particular morphology, fluorescence and viscosity. Compared with other nitrogen compounds necessary for N-GQDs synthesis, ammonia is much more suitable due to its low toxicity and stability. Synthesized TAC and N-GQD were identified by FT-IR, XRD, TGA, EDS, SEM, crystallography and fluorescence.

Ecological assessment of the toxicity of nitrogen compounds for aquatic organisms using the Lemna minor L. Biotest

This research is motivated because of increasing eutrophication problems in water bodies. This happens as a result of excess nitrogen and phosphorus. Too many of these nutrients can cause algae to grow, leading to blooms. Harmful algal blooms consume dissolved oxygen in water. As a result, the oxygen level decreases, affecting the aquatic ecosystem. The stenobiont plant, which belongs to the group of the most sensitive bioassays, is the small duckweed Lemna minor L. This plant is sensitive to increasing levels of nutrients and blooms of algae. This research aimed to determine the level of water toxicity using the bioassay of duckweed (Lemna minor L.) to establish dangerous concentrations of nitrogen compounds (NO2-, NO3-, NH4+) (CA) for higher plants of aquatic ecosystems with subsequent risk forecast for Dnipro basin. The research was carried out in accordance with DSTU 32426-2013 “Testing of chemicals of environmental hazard. Lemna sp. Growth Inhibition. Test”. The number of effects associated with nitrogen compounds (NO2-, NO3-, NH4+) on plant growth and development during the testing period was detected. The number of green layers is the main variable that was investigated in the experiment. Changes in the morphological features of duckweed were also studied, in accordance with the standard, the toxicity of water was assessed by changes in leaf colour, manifestations of chlorosis, the transformation of whole plants into individuals, the appearance of young leaves. To estimate the number of effects associated with the nitrogen compounds toxicity, the half-maximal effect (EC50) was studied. It should be noted that studies of water toxicity on NO2- content using the Lemna minor L. test showed that even at the lowest concentration of 0.1 mgNO2-/L aquatic biota will be significantly affected by the toxicity with possible subsequent death. Summarizing the results of the research of the Lemna minor L reaction to the toxicity of water with different concentrations of NO3- came to the conclusion that even the lowest concentration (0.1 mgNO3-/L) will have a negative impact on their growth and development of the plant. Generally, 40.0 mgNO3-/L is considered “safe” for fish farming. However, this is not a case for aquatic vegetation, as shown by this result – such concentration will be toxic and cause death. If we take into account NH4+ salts, the reaction was even more progressive, the deterioration of the leaf layers of duckweed began to occur immediately from the first days of the research, and the number of damaged duckweed was 30% more on day 24 than in salts NO3-, NO2-. For algae of aquatic ecosystems the highest level of toxicity is shown by nitrogen compounds in the form of NO3-, the median concentration of EC50 (96 hours) is 7.7 mg/L. Therefore, the regulation of pollution of aquatic ecosystems by nitrogen compounds should be based primarily on the content of NO3-. To avoid the negative effects of compounds such as NH4+ and NO2- it is necessary to take into account their toxicity level: EC50 (96 hours) NH4+ – 250 mg/L, EC50 (96 hours) NO2- – 720 mg/L. From the above, the free-floating hydrophyte Lemna minor L. is a promising object of testing, as it easily absorbs all the elements and quickly shows the result. It is able to quickly accumulate harmful substances, because in the process of life, its leaves absorb absolutely all the elements that fall into the water.

Unstable Relationship Between Braarudosphaera bigelowii (= Chrysochromulina parkeae) and Its Nitrogen-Fixing Endosymbiont

Marine phytoplankton are major primary producers, and their growth is primarily limited by nitrogen in the oligotrophic ocean environment. The haptophyte Braarudosphaera bigelowii possesses a cyanobacterial endosymbiont (UCYN-A), which plays a major role in nitrogen fixation in the ocean. However, host-symbiont interactions are poorly understood because B. bigelowii was unculturable. In this study, we sequenced the complete genome of the B. bigelowii endosymbiont and showed that it was highly reductive and closely related to UCYN-A2 (an ecotype of UCYN-A). We succeeded in establishing B. bigelowii strains and performed microscopic observations. The detailed observations showed that the cyanobacterial endosymbiont was surrounded by a single host derived membrane and divided synchronously with the host cell division. The transcriptome of B. bigelowii revealed that B. bigelowii lacked the expression of many essential genes associated with the uptake of most nitrogen compounds, except ammonia. During cultivation, some of the strains completely lost the endosymbiont. Moreover, we did not find any evidence of endosymbiotic gene transfer from the endosymbiont to the host. These findings illustrate an unstable morphological, metabolic, and genetic relationship between B. bigelowii and its endosymbiont.