Nafta-Gaz最新文献

{"title":"The method for calculating technological indicators in the development of gas wells while considering the thermobaric and thermodynamic conditions within the “reservoir-well” system","authors":"Elmira V. Gadasheva, Sudaba H. Novruzova","doi":"10.18668/ng.2023.10.06","DOIUrl":"https://doi.org/10.18668/ng.2023.10.06","url":null,"abstract":"Considering the substantial prevalence of gas fields in the pool of developed fields, their development requires specialized approaches with the primary objective of optimizing the production process. The effectiveness of gas field development hinges on achieving the highest possible gas recovery factor. Achieving a high limit of the ultimate return of gas fields relies on decisions that vary depending on the precision of design estimates carried out at different stages of development and their timely execution. The accuracy of such estimates is, if possible, directly contingent on the thorough consideration of geological, technical, and technological factors when formulating methods for determining field development and operation indicators. Given the above considerations, this article proposes a methodology for determining the technological indicators of gas reservoir development, which enables to anticipate changes in reservoir pressure, temperature, and porosity of the gas reservoir, while accounting for the gas-dynamic interplay within the “reservoir-well” system in the depletion phase. The developed approach makes it possible to reliably ascertain reservoir development metrics by factoring in well conditions, temperature distribution within the reservoir, and reservoir deformation. In addition, it facilitates the necessary assessment for determining optimal well operations in light of reservoir conditions.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136159932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The conversıon of ethanol to acetone on a ZnO-CaO catalyst in the presence of water vapor","authors":"Narqiz N. Baghirova, Rena E. Mustafayeva","doi":"10.18668/ng.2023.10.07","DOIUrl":"https://doi.org/10.18668/ng.2023.10.07","url":null,"abstract":"The main product of the conversion of ethanol to acetone on a ZnO-CaO catalyst is acetone, the yield of which strongly depends on the composition of the reaction environment. When oxygen is present, the yield of products of destructive and complete oxidation increases greatly. In contrast, when water vapor is present, both the selectivity and conversion of ethanol increase. Therefore, the conversion of ethanol is the limiting step in the overall process, which determines the selectivity of the conversion of ethanol to acetone. In this regard, it appeared suitable to investigate the effect of introducing water to the contact zone. As experiments indicated, the addition of water caused a significant effect on the conversion, selectivity, and acetone yield on the ZnO-CaO catalyst. As the partial pressure of water vapor increases, the conversion of ethanol and the acetone yield increase, while the yield of carbon dioxide decreases. The decrease in carbon dioxide is associated not only with the inhibition of the conversion of ethanol to CO2. In this study, the adsorption of water vapor and ammonia on the surface of the ZnO-CaO catalyst was examined by infrared spectroscopy method. It has been shown that water vapor at low temperatures is adsorbed on the catalyst surface in the molecular form, while at higher temperatures it is adsorbed in the dissociative form. Co-transformation reactions of ethanol with acetic acid, acetaldehyde with ethylene, and acetaldehyde with acetic acid have been studied. The obtained results indicated that acetone is formed mainly through the stage of complexation of acetaldehyde with ethylene. The isomerization reaction of 1-butene to 2-butene has been investigated. It was found that the yield of cis-2-butene in the absence of water vapor is higher, likely attributed to the molecular adsorption of water on Lewis centers. Based on these findings, a scheme for the vapor-phase conversion of ethanol into acetone on the studied catalysts was formulated.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136160596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wykorzystanie języka R do statystycznej analizy oraz analizy skupień dla danych geochemicznych","authors":"Marek Janiga","doi":"10.18668/ng.2023.09.02","DOIUrl":"https://doi.org/10.18668/ng.2023.09.02","url":null,"abstract":"W zagadnieniach geologii naftowej metody statystyczne są szeroko stosowane w petrografii, petrofizyce, geochemii, geomechanice, geofizyce wiertniczej czy sejsmice, a analiza skupień jest istotna w klasyfikacji skał – wyznaczaniu stref o pewnych własnościach, np. macierzystych lub zbiornikowych. Artykuł prezentuje użycie metod statystycznych, w tym metod analizy skupień, w procesach przetwarzania i analizy dużych zbiorów różnorodnych danych geochemicznych. Do analiz statystycznych wykorzystano literaturowe dane z analiz składu chemicznego i izotopowego gazów ziemnych. Wyniki zawierały skład chemiczny gazów ziemnych oraz skład izotopowy. Zastosowano algorytmy tzw. nienadzorowanego uczenia maszynowego do przeprowadzenia analizy skupień. Grupowania było przeprowadzone dwiema metodami: k-średnich oraz hierarchiczną. Do zobrazowania wyników grupowania metodą k-średnich można wykorzystać dwuwymiarowy wykres (funkcja fviz_cluster języka R). Wymiary na wykresie to efekt analizy głównych składowych (PCA) i są one liniową kombinacją cech (kolumn w tabeli). Wynikiem grupowania metodą hierarchiczną jest wykres nazywany dendrogramem. W artykule dodatkowo zaprezentowano wykresy pudełkowe i histogramy oraz macierz korelacji zawierającą współczynniki korelacji Pearsona. Wszystkie prace wykonano z użyciem języka programowania R. Język R, z wykorzystaniem programu RStudio, jest bardzo wygodnym i szybkim narzędziem do statystycznej analizy danych. Przy użyciu tego języka uzyskanie wymienionych powyżej wykresów, tabeli i danych jest szybkie i stosunkowo łatwe. Wyniki analiz składu gazu wydają się mało zróżnicowane. Mimo to dzięki algorytmom k-średnich i hierarchicznym możliwe było pogrupowanie danych geochemicznych na wyraźnie rozdzielne zespoły. Zarówno wartości składu izotopowego, jak i skład chemiczny pozwalają wyznaczyć grupy, które w inny sposób nie byłyby dostrzegalne.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134962009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental studies of the carrying capacity of the drilling fluid","authors":"Igor Chudyk, Ivan Dudych, Mykola Seniushkovych, Ivan Vytvytskyi, Andrii Vytiaz","doi":"10.18668/ng.2023.09.03","DOIUrl":"https://doi.org/10.18668/ng.2023.09.03","url":null,"abstract":"The main factors affecting the efficiency of the carrying capacity of drilling fluid are analysed in the paper. A description of the design of an experimental setup for modeling the well flushing process is presented, which makes it possible to evaluate the efficiency of the carrying capacity of a fluid from a variety of factors under study. To conduct experimental studies of the influence of factors on the efficiency of cleaning wells from cuttings, an experimental plan was built using the Taguchi methods for six factors at three levels of their change. According to the plan, we studied the effect of such parameters on the carrying capacity of the drilling fluid at various values of its flow rate: the variability of the drill string in the well; the cuttings particle diameter; the plastic viscosity of the drilling fluid; the pulsation frequency; the rotation of the drill string and its longitudinal movement. The nature of the formation of stagnant rock zones in the annulus of directional wells has been assessed. The influence of factors according to the constructed plan of the experiment at the distance of the beginning of settlement of the cuttings was studied. Based on the results of the studies, it was found that changing the range of these factors reduces the volume of rock deposited on the lower wall of the directional wellbore. It has been established that the use of a pulsating flow of flushing fluid makes it possible to reduce the value of its consumption and improve the efficiency of cleaning the annular space of wells from cuttings.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134961998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The modification of filtration properties of porous pedia using Multizol micellar treatment fluid","authors":"Marcin Majkrzak, Sławomir Falkowicz, Winicjusz Stanik","doi":"10.18668/ng.2023.09.01","DOIUrl":"https://doi.org/10.18668/ng.2023.09.01","url":null,"abstract":"The need for the modification of filtration properties of rock media (most frequently porous rocks) appears frequently, e.g., in hydrocarbon exploitation. Exploitation of crude oil and natural gas is frequently accompanied by an excessive and uncontrolled inflow of reservoir water to the production well, which often results in a significant reduction of hydrocarbon production in the late period of reservoir exploitation. The control of water inflow, through modification treatments of rock filtration properties of the near wellbore zone, is the solution to this problem. The use of dedicated treatment fluids is the basis of such success, which, after the injection and change of original physicochemical properties, create local insulation barriers, enabling the control of the flow of fluids in the geological formation. This paper presents the results of the laboratory assessment of the technological effectiveness of Multizol micellar treatment fluid, which is used for selective blocking of the reservoir water inflow to gas wells. Tests performed, at a preliminary stage, comprised the development of a procedure, the obtaining of samples of the treatment fluid, and the performance of flow tests in test glass tubes, which allow for a swift determination of the technological range of the fluid's capability to form gel and emulsion. Flood tests were the main element of testing, related to the measurement of pressure drops of fluids flowing through the sample under the simulated reservoir conditions. The tests were carried out using two types of media, porous rocks (Szydłowiec sandstone) and sand packs. The determination of the modification degree of filtration properties, both in individual zones and in the entire sample/model, was based on the value of the FRR (Residual Resistance Factor) coefficient, being the measure of their permeability reduction. Two types of tests were performed to assess the effect of Multizol treatment fluid on the initial filtration properties of gas and water-bearing zones.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134962077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of the friction force between the draw rod and its guide in sucker rod well pumps and an analytical study of the stress deformation state of the valve assembly","authors":"Sevda Y. Aliyeva, Sakit H. Abbasov","doi":"10.18668/ng.2023.09.05","DOIUrl":"https://doi.org/10.18668/ng.2023.09.05","url":null,"abstract":"The article is devoted to the determination of the friction force between the draw rod and the guide and to the analytical study of the stress deformation state of the valve assembly of the rod well pump. In sucker rod well pumps, a hollow cylindrical guide is used to ensure the same axis of the plunger as the cylinder during operation. The guide is attached to the upper end of the pump cylinder. The draw rod connecting the sucker rod and the plunger of the pump moves up and down in the internal cylindrical cavity of the guide in the corresponding movements of the balancer head. There must be a certain clearance between the draw rod and the guide to ensure free movement of the draw rod. Based on the calculation scheme for determining the friction force between the draw rod and the guide is given, and the necessary parameters are determined. According to the values obtained from the calculation, the graphs were built based on the dependences of the friction force between the draw rod and the guide on the angle φ, and on the path of the plunger when φ = 30. At the same time, according to the calculation scheme of the \"ball-saddle\" pair, the force acting on the ball, the stresses generated on the contact surfaces of the ball and the saddle, and other parameters were found. The friction and wear between the draw rod and the guide is also typical of the friction and wear between the polished rod and the wellhead forming structure. Because, in the latter case, as a result of the suspension point of the balancer head not having the same axis as the wellhead, the polished rod cannot move with the straight axis in wellhead valve.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134961925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of the exact daily gas intake according to the level of formation completion in the underground gas storage","authors":"Nargiz R. Akhundova, Ofeliya Aliyeva","doi":"10.18668/ng.2023.09.04","DOIUrl":"https://doi.org/10.18668/ng.2023.09.04","url":null,"abstract":"This article derives the formula for the exact daily gas intake of a gas-dynamic incomplete flatbed gas injection well according to the level of formation completion in the underground gas storage (UGS). In natural gas fields and underground gas storages, the formation is incompletely saturated with hydrocarbons due to the level of completion of the formation. In the upper part of the formation there is a flat-radial simple leakage flow through the gas well, and in the unopened part there is a complex curved radial flow. Separate formulas have been developed for the exact daily volume consumption of hydrocarbon gas injected into these wells. For this purpose, gas dynamics problems for two different stationary gas flows have been solved. By adding up the daily volume of gas consumption according to these formulas, the formula of full daily consumption for replaced well No. 2 was obtained. Which is equal to the exact full daily volume consumption of flatbed well No. 1. Fluids and gases are known to enrich the water supply and field system. The boundaries of the latter are the contours of the pressure and the flow. The water pressure in the reservoir was determined by changing the sum of the volume of the cavity at the edge of the reservoir, the capacity of the created gas and the amount of injected gas.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134961824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analiza składu pierwiastkowego biowęgla z wykorzystaniem spektrometrii ICP OES i metod chemometrycznych","authors":"Marek Kozak","doi":"10.18668/ng.2023.09.07","DOIUrl":"https://doi.org/10.18668/ng.2023.09.07","url":null,"abstract":"W pracy wykonano oznaczenia 20 pierwiastków w próbkach karbonizatów otrzymanych w wyniku pirolizy biomasy stałej pochodzenia roślinnego oraz próbki osadów ściekowych – biomasy stanowiącej uboczny produkt procesu oczyszczania ścieków. Najniższe stężenia pierwiastków oznaczono w karbonizatach biomasy roślinnej otrzymanych z trocin sosnowych, natomiast najwyższe w próbkach karbonizatów osadów ściekowych. Ten ostatni rodzaj odpadów z procesu oczyszczania ścieków zawierał największe stężenia takich składników mineralnych jak: wapień, magnez, żelazo, siarka i fosfor, lecz także metali ciężkich: chromu, miedzi, niklu, molibdenu, ołowiu, wanadu i cynku. W karbonizatach otrzymanych z materiału roślinnego w najwyższych stężeniach oznaczono: potas, wapń, magnez i fosfor – makroelementy niezbędne do prawidłowego zachowania funkcji życiowych roślin. W celu określenia prawidłowości oraz relacji występujących pomiędzy danymi pomiarowymi zastosowano metody chemometryczne. W badaniach wykorzystano analizę wiązkową (ang. cluster analysis), tzn. metodę grupowania badanych próbek w taki sposób, aby obiekty podobne znajdowały się w tej samej grupie. W wyniku przeprowadzenia obliczeń otrzymano cztery skupienia. Dla każdego skupienia obliczono średnie stężenia pierwiastków wchodzących w jego skład oraz sumaryczne stężenie oznaczanych pierwiastków. Skupienia te to dwa składające się z próbek jednego rodzaju i pozostałe dwa, z których każde zawierało dwie różnego rodzaju próbki. Zaobserwowano, że w przypadku próbek biomasy roślinnej (skorupy orzechów włoskich), dla których zastosowano dwa odmienne sposoby ogrzewania, próbki tego samego rodzaju zostały zaklasyfikowane do różnych skupień: pierwszego – po ogrzewaniu tradycyjnym i drugiego – po ogrzewaniu mikrofalowym. W warunkach prowadzenia procesu pirolizy z wykorzystaniem ogrzewania mikrofalowego oznaczono badane pierwiastki w stężeniach 2–4 razy wyższych, niż gdy proces był prowadzony w tej samej temperaturze, ale z użyciem ogrzewania tradycyjnego.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134962281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study of factors affecting wear and destruction of teeth in gear mechanisms","authors":"Amir G. Mustafayev, Chingiz R. Nasirov","doi":"10.18668/ng.2023.09.06","DOIUrl":"https://doi.org/10.18668/ng.2023.09.06","url":null,"abstract":"Transmission gears are very widely used in the modern construction of the machine. Even though electrical transmissions are used, mainly mechanical transmissions are widely used in the machine building industry as they are independent and better than other transmissions. Distributing power between the transmission mechanisms and working units of various machines, by changing the angle of momentum by adjusting the speed of the parts, it is possible to change the type of movement, turn the mechanism on and off, and change the direction of the transmission mechanisms. One of the most widespread types of transmission technology is gear transmission. Tens of thousands of kilowatt-hours of gears can be transmitted. The advantages of gear transmission in comparison with others are their ability to maintain their reliability and long-term functioning of the teeth, high value of the working coefficient (0.90–0.99), simple construction, lack of special service, simplicity of the transmission number and compactness of dimensions. The missing aspects of these transmissions are high precision in their preparation and installation, and low noise level. The main criterion for the working ability of the closed gear transmissions is the contact endurance of the active surface of the tooth. For this reason, the main dimensions of the transmission are determined by the contact tension and by teeth bending.","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134962241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ocena potencjału węglowodorowego łupku miedzionośnego pochodzącego z południowej części monokliny przedsudeckiej","authors":"M. Kania, K. Spunda, Agnieszka Wciślak-Oleszycka","doi":"10.18668/ng.2023.08.02","DOIUrl":"https://doi.org/10.18668/ng.2023.08.02","url":null,"abstract":"\"Głównym celem pracy była próba określenia możliwości generacji węglowodorów z poziomu łupku miedzionośnego na podstawie wyników badań pirolitycznych. W celu oceny materii organicznej 13 próbek rdzeniowych pochodzących z rejonu złóż rud miedzi w południowej części monokliny przedsudeckiej poddano badaniom pirolitycznym Rock-Eval. Dodatkowo próbki skalne badano również przy użyciu pirolizy wysokotemperaturowej sprzężonej z kapilarną chromatografią gazową (Py-GC/FID) i studiowano pod kątem zmienności trzech grup węglowodorowych: lekkich – C1–C9, ciekłych – C10–C15 oraz ciężkich – powyżej C15+. W przypadku każdej próbki została zastosowana jednoetapowa piroliza, prowadzona w programowanej temperaturze 500°C przez 0,4 min. Uzyskane wyniki były interpretowane kompleksowo i pozwoliły na rozróżnienie charakteru generowanych produktów na podstawie dystrybucji węglowodorów otrzymanych w wyniku pirolizy substancji organicznej zawartej w skale. Do określenia potencjalnych możliwości generacyjnych badanych łupków miedzionośnych wykorzystano zarówno udział procentowy poszczególnych frakcji, jak też bezwymiarowy wskaźnik uzysku (liczony z analizy Py-GC/FID). Na podstawie wyników badań pirolitycznych Rock-Eval oraz zbieżnych z nimi wartości wskaźników uzysku Py-GC/FID stwierdzono doskonały potencjał węglowodorowy dla wybranych próbek pochodzących z poziomu łupku miedzionośnego. Stopień dojrzałości substancji organicznej wyrażony poprzez parametr Tmax w przypadku większości badanych próbek z poziomu łupku miedzionośnego mieści się w zakresie okna ropnego, co potwierdziły również badania Py-GC/FID. Dodatkowo o możliwości generacji węglowodorów świadczy fakt występowania wysokiej zawartości ekstrahowalnej substancji organicznej oraz bardzo wysoka wartość parametru S2 (nawet do 41,88 mg HC/g skały). Analiza wyników badań geochemicznych pod kątem oceny potencjału generacyjnego poziomu łupku miedzionośnego udowodniła, że poziom ten nie powinien być pomijany jako potencjalnie macierzysty przy rozpatrywaniu źródła napełniania pułapek węglowodorów w systemie naftowym Niżu Polskiego.\"","PeriodicalId":45266,"journal":{"name":"Nafta-Gaz","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81985985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}