Utjecaj tehnologije raspršivanja na performanse apsorbera u H2O/LiBr apsorpcijskom rashladnom uređaju

For major thermal engines used in industrial sectors, the use of chillers has been growing steadily over the previous decades. Indeed, this is linked strongly to their large energy performance despite their investment costs, which are still high, in particular for low powers. Performance coefficients for absorption chillers are relatively low, and their profitability depends on the costs of the main equipment and more particularly on the price of the absorber. Several studies focusing on the development of mass contactors are underway with the principal objective of further improving their performance of mass and energy transfer. Relating to the mass and heat transfer, it is specified that the contact between the phases in circulation is ensured by different types of contactors. The transfer performance is correlated with the heat and mass transfer coefficient on the one hand, and the specific exchange area, i.e., the exchange area per unit volume of the contactor on the other hand. These contactors are distinguished by their mode of contact between phases (bubbling, spraying, falling film, etc.). While the exchange coefficient depends on the hydrodynamics regime in the contactor (flow regime and physicochemical properties of phases), the specific exchange area is dictated by its operating mode. Any limitation of its use for a specific application (physicochemical phenomena, such as crystallisation, deposited dust, etc.) requires research and development of better devices more adapted. Moreover, the most used contactors in chemical engineering are plate columns, packed columns, falling film columns, spray columns, etc. In order to intensify exchanges, a new absorber of the pulverised type is to be explored in relation with the physicochemical properties of the phases, and of their hydrodynamic flow conditions in the sprayed column. Therefore, an experimental study of the influence of operating variables (nozzle diameter, fluids flow rate, their concentrations, size of droplets, etc.) on the overall coefficient of mass transfer in gaseous phase in the absorber of the absorber chiller was conducted. After having fixed the pressure in the absorber, the first part of the study allowed developing new correlations linking the experimental results of the KG ∙ a to all operating variables (L, C, dd, etc.). The second part was devoted to the simulation of the absorption chiller functioning by introducing the concept of energy and exergy yields based on the mass transfer correlations.Posljednjih desetljeća vidljiv je stalan porast upotrebe rashladnih uređaja kod glavnih toplinskih motora koji se upotrebljavaju u industrijskim sektorima. Koeficijenti učinka apsorpcijskih rashladnih uređaja relativno su niski, a njihova isplativost ovisi o troškovima glavne opreme, točnije o cijeni apsorbera. U tijeku je nekoliko studija razvoja kontaktora masa usmjerenih na poboljšanje prijenosa tvari i energije u kontaktorima. Vezano uz prijenos tvari i topline, specificirano je da se kontakt između cirkulirajućih faza ostvaruje različitim tipovima kontaktora. Učinak prijenosa koreliran je s koeficijentom prijenosa tvari i topline s jedne strane te specifičnom površinom izmjene, tj. površinom izmjene po jedinici volumena kontaktora, s druge strane. Kontaktori se razlikuju po načinu kontakta faza (mjehurići, raspršenje, padajući film, itd.). Dok koeficijent izmjene ovisi o hidrodinamičkom režimu u kontaktoru (režim protoka i fizikalno-kemijska svojstva faza), specifična površina izmjene ovisi o njegovu načinu rada. Ograničenje njegove uporabe na neku određenu primjenu (fizikalno-kemijske pojave poput kristalizacije) zahtijeva istraživanje i razvoj uređaja koji bi više bili prilagođeni spomenutoj primjeni. Štoviše, najčešće upotrebljavani kontaktori u kemijskom inženjerstvu su kolone s pliticama, kolone s punilima, kolone s padajućim filmovima, kolone za raspršivanje, itd. S ciljem povećanja izmjena, istražit će se novi praškasti apsorber i to s obzirom na fizikalno-kemijska svojstva faza i njihove hidrodinamičke uvjete strujanja u koloni za raspršivanje. Stoga je provedeno istraživanje utjecaja radnih varijabli (promjera mlaznice, protoka fluida, koncentracije fluida, veličine kapljica, itd.) na ukupni koeficijent prijenosa tvari u plinovitoj fazi u apsorberu rashladnog uređaja. Nakon fiksiranja tlaka u apsorberu, prvi dio istraživanja omogućio je razvoj novih korelacija koje povezuju eksperimentalne KG ∙ a rezultate sa svim radnim varijablama (L, C, dd, itd.). Drugi dio bio je posvećen simulaciji rada apsorpcijskog rashladnog uređaja uvođenjem koncepta energetskih i eksergijskih prinosa temeljenih na izrazima za prijenos tvari

New Isolated Extremophiles Arsenic Oxidizing Bacteria for the Removal of Arsenic from High- and Low-COD Media

There is an urgent need for the removal of arsenic (As) from groundwater and wastewater as it is a very hazardous heavy metal for human and environmental health. In this research, As-resistant and oxidizing bacteria were isolated from the Maharloo Lake (27 km southeast of Shiraz city) and identified to a great extent. Three isolated bacillus-shaped strains (called F5, F6 and F7) tolerated up to 1 M AsNaO2, grew up to 3.5 M NaCl and pH 12, and consumed NaSCN and Na2S2O3. The molecular analysis confirmed the originality of the strains to a high extent. The As absorption rate by these bacteria was measured by the atomic absorption method, and their effect was examined on a water sample from the south of Kerman city (Iran) and a synthetic wastewater sample with a chemical oxygen demand (COD) of about 180,000 kg/m3 that was able to absorb high levels of arsenic

A Wirelessly Controlled Smart Bandage with 3D-Printed Miniaturized Needle Arrays

PUBLIC ACCES

Control of paratuberculosis: who, why and how. A review of 48 countries

Paratuberculosis, a chronic disease affecting ruminant livestock, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It has direct and indirect economic costs, impacts animal welfare and arouses public health concerns. In a survey of 48 countries we found paratuberculosis to be very common in livestock. In about half the countries more than 20% of herds and flocks were infected with MAP. Most countries had large ruminant populations (millions), several types of farmed ruminants, multiple husbandry systems and tens of thousands of individual farms, creating challenges for disease control. In addition, numerous species of free-living wildlife were infected. Paratuberculosis was notifiable in most countries, but formal control programs were present in only 22 countries. Generally, these were the more highly developed countries with advanced veterinary services. Of the countries without a formal control program for paratuberculosis, 76% were in South and Central America, Asia and Africa while 20% were in Europe. Control programs were justified most commonly on animal health grounds, but protecting market access and public health were other factors. Prevalence reduction was the major objective in most countries, but Norway and Sweden aimed to eradicate the disease, so surveillance and response were their major objectives. Government funding was involved in about two thirds of countries, but operations tended to be funded by farmers and their organizations and not by government alone. The majority of countries (60%) had voluntary control programs. Generally, programs were supported by incentives for joining, financial compensation and/or penalties for non-participation. Performance indicators, structure, leadership, practices and tools used in control programs are also presented. Securing funding for long-term control activities was a widespread problem. Control programs were reported to be successful in 16 (73%) of the 22 countries. Recommendations are made for future control programs, including a primary goal of establishing an international code for paratuberculosis, leading to universal acknowledgment of the principles and methods of control in relation to endemic and transboundary disease. An holistic approach across all ruminant livestock industries and long-term commitment is required for control of paratuberculosis

Novel recombinant Mce-truncated protein based ELISA for the diagnosis of Mycobacterium avium subsp. paratuberculosis infection in domestic livestock.

Johne's disease (JD) is an infectious wasting condition of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP) in domestic livestock of every country that has been investigated. Controlling JD is problematic due to the lack of sensitive, specific, efficient, and cost-effective diagnostic tests. A major challenge in the development of diagnostics like ELISA is the selection of an ideal antigen/(s) that is pathogen-specific and allows sensitive recognition. Therefore, the purpose of this study was to identify and use Mce-truncated protein-based ELISA assay for the diagnosis of MAP infection with high sensitivity and specificity. In silico epitope prediction by epitope mapping throughout the whole length of MAP2191 protein revealed that C-terminal portion of this protein presented potential T- and B-cell epitopes. Therefore, a novel Mce-truncated protein encoded by the selected region of MAP2191 gene was expressed, purified with Ni-NTA gel matrix and confirmed by SDS PAGE and western blot. A profiling ELISA assay was developed to evaluate sera from MAP infected and non-infected ruminant species for antibodies against Mce-truncated protein to infer the immunogenicity of this protein in the host. Using this Mce protein-based ELISA, 251 goats, 53 sheep, 117 buffaloes, and 33 cattle serum samples were screened and 49.4, 51.0, 69.2, and 54.6% animals, respectively, were found positive. Comparing with i-ELISA, the new Mce-based ELISA kit showed a relatively higher specificity but suffered from slightly reduced sensitivity. Mce-based ELISA excluded apparently false positive results of i-ELISA. Mce protein was found to be antigenic and Mce-ELISA test could be employed as a diagnostic test for JD in domestic livestock in view of the a relatively higher specificity and accuracy. The antigenic potential of Mce antigen can also be exploited for the development of a new vaccine for the control of MAP infection

Immuno-reactivity evaluation of Mce-truncated subunit candidate vaccine against Mycobacterium avium subspecies paratuberculosis challenge in the goat models

Abstract Background Detection of an appropriate antigen with high immunogenicity can be a big step in the production of an effective vaccine for control of Johne’s disease (JD). The aim of this study was to evaluate the efficacy of Mce-truncated protein as a subunit vaccine candidate for the control of JD in experimentally challenged goats. Materials and methods Six healthy goat kids were immunized with Mce-truncated protein, and two goats were kept as controls. All kids were twice challenged orally with live Mycobacterium avium subspecies paratuberculosis(MAP) strain and half the goats from both the categories were sacrificed at 7 and 10 months after start of challenge study. Culture of MAP was performed from all the necropsied tissues to determine the true JD infection status. Results Mce-truncated protein only reacted with pooled vaccinated goat sera in western-blot. A significant increase in humoral immune response against Mce protein was also observed in vaccinated goats. Compared to the control group, vaccinated goats gained higher body weights and none of them shed MAP or showed histopatological lesions or colonization of MAP in their necropsy tissues. Conclusions The new Mce protein based vaccine provided significant immunity in goats as they could meet the challenge with live MAP bacilli. Although the vaccine used in this study showed the high potential as a new effective vaccine for the control of JD, further validation study is still required to successfully implement the vaccine for JD control program

Forest fire risk modeling using logistic regression and geographic ınformation systems: a case study in Muğla - Milas

Orman yangınları önemli bir çevre sorunu olmakla beraber tüm ekosistem ve içerisindeki insan ve hayvan yaşamını olumsuz yönde etkilemektedir. Türkiye’de son 20 yılda yaşanan 46.669 orman yangınında toplamda 192.734 hektar orman alanı zarar görmüştür. Bu yangınların ortaya çıkış nedenlerinde ise ilk sırada ihmal-kaza bulunmaktadır. Bu nedenle meydana gelen orman yangınlarının sıklığını en aza indirmek ve zararları önlemek için yangın riski olan alanların belirlenerek, yangın öncesinde, sırasında ve sonrasında alınacak önlemler için hazırlıklı olunması gerekmektedir. Bu çalışmada Muğla ili Milas ilçesi için orman yangını riskini modellemede Lojistik Regresyon (LR) ve Coğrafi Bilgi Sistemleri (CBS) kullanılmıştır. Topoğrafik özellikler, meşcere verileri ve kültürel veriler dikkate alınarak, bu faktörlerin yangınların oluşumu ile ilişkisi araştırılmıştır. LR ile yangın risk tahmininin doğruluk analizleri ve farklı özelliklerdeki alanların yangın riskleri Alıcı Çalışma Karakteristiği (ROC) ve Hosmer-Lemeshow testi ile incelenmiştir. Lojistik Regresyon yöntemi ile elde edilen bulgular doğrultusunda CBS ortamında bir orman yangını risk haritası oluşturulmuştur. Burada orman yangını riski “1” çok düşük riskli ve “5” çok yüksek riskli olmak üzere beş seviyede değerlendirilmiştir. Ortaya çıkan orman yangını risk haritasında, çalışma alanında bulunan toplam orman alanlarının %16’sının yüksek ve çok yüksek risk sınıfında bulunduğu sonucuna varılmıştır.Forest fires are an important environmental problem, they negatively affect the entire ecosystem and human and animal life in it. In Turkey 192.734 hectares of forest area has been damaged in 46.669 forest fires in the last 20 years. Negligence-accident is the primary cause of these fires. For this reason, in order to minimize the frequency of forest fires and prevent damages, areas with fire risk should be determined and it is necessary to be prepared for the precautions to be taken before, during and after the fire. In this study, Logistic Regression (LR) and Geographic Information Systems (GIS) were used to model the forest fire risk for the Milas province in Muğla. Considering the topographic features, stand data and cultural data, the relationship of these factors with the occurrence of fires was investigated. Accuracy analyzes of fire risk estimation with LR and fire risks of areas with different properties were examined by Receiver Operating Characteristic (ROC) and Hosmer-Lemeshow test. In line with the findings obtained by the LR method, a forest fire risk map was created in the GIS environment. Here, forest fire risk is evaluated at five levels, with “1” very low risk and “5” very high risk. In the resulting forest fire risk map, it was concluded that 16% of the total forest areas in the study area are in high and very high risk classes

Additional file 1 of Immuno-reactivity evaluation of Mce-truncated subunit candidate vaccine against Mycobacterium avium subspecies paratuberculosis challenge in the goat models

Supplementary Material