Buckling behaviour of dented aluminium alloy cylindrical shell subjected to uniform axial compression

Tankozide cilindrične strukture imaju veoma visoku primenu u industriji. Pošto su obično opterećene na aksijalni pritisak, najčešći uzrok njihovog otkaza je pojava izvijanja. U ovom članku se prikazuje numerička analiza izvijanja tankozide cilindrične strukture izrađene od legure aluminijuma sa imperfekcijom u vidu udubljenja na sredini strukture i eksperimentalna verifikacija rezultata dobijenih tom analizom. Numerička analiza je odrađena pomoću softvera ANSYS 16.2, a eksperimentalna ispitivanja pomoću hidraulične prese Armavir, PSU-50, na kojoj je uzorak podvrgnut aksijalnom pritisku čiji se intenzitet postepeno povećavao do pojave izvijanja. Poređenjem rezultata eksperimenta uočeno je značajno smanjenje vrednosti kritičnog napona na izvijanje između epruveta bez imperfekcije i epruveta sa imperfekcijom od 2 mm, dok su vrednosti kritičnog napona za epruvete sa imperfekcijama od 2 mm i 4 mm približne.Thin-walled cylindrical shells are commonly used in numerous branches of industry. Since they are subjected to axial load, the most common cause of their failure is buckling. This paper provides numerical analysis and experimental verification of the buckling of the thin-walled aluminium alloy cylindrical shell with special regard to the influence of dent, positioned in the middle of the shell. Numerical simulation was performed using ANSYS 16.2, and experimental verification was performed by means of hydraulic press Armavir, PSU-50, which was used to subject the specimen to the increasing axial load until the occurrence of buckling. Comparing the results it was concluded that there is significant decrease of the buckling resistance if compared the values of the specimen with no dent, and the specimen with 2 mm deep dent. On the contrary, resistance of the 2 mm and 4 mm dented specimen is quite similar. Position and shape of the deformations occurred due to buckling are matching if experimental and numerical results are compared

In vitro студија редокс особина азолил-лактона у хуманом серуму

Disruption of the redox balance in the body causes oxidative stress that can initiate many diseases. While antioxidants reduce the level of oxidiz- ing compounds in the medium, prooxidants promote the opposite process and have been used in therapies in particular those of cancer diseases. In this study, a series of azolyl lactones, were tested in human serum as a biological matrix and the obtained values of their oxy scores (OS) were compared. The antioxid- ative properties of these compounds were also tested under conditions of ind- uced oxidative stress using an external prooxidant, t-butylhydroperoxide. The results showed that the sulphur analogue 4-azolyl coumarin 5 has the best anti- oxidant properties (OS –2.2), while the halogenated derivatives of pyrazolyl- coumarin 7 and 8 act as prooxidants, but successfully resist oxidative stress (OS 2.7 and 2.0, respectively). Related phthalides and isocoumarins showed prooxidative properties, but azolyl isocoumarins 10 and 11 show the strongest resistance to oxidative stress, reflected in their negative oxy score value (OS –2.1 and –1.1, respectively). The results demonstrated that combining two pharmacophores with known redox properties can produce potent compounds in both directions, with the antioxidative and the prooxidative characteristics.Поремећај редокс баланса у организму може узроковати оксидативни стрес, који је окидач за настанак многих болести. Антиоксиданси снижавају ниво оксидујућих једи- њења у медијуму у коме се налазе, док прооксиданси делују супротно и као такви могу наћи примену у терапији канцера. У овом истраживању, испитиване су антиоксидативне и прооксидативне особине серије азолил-лактона у хуманом серуму као биолошком матриксу. Антиоксидативне особине су представљене помоћу окси скорова (ОS), а испи- тивано је и понашање ових једињења у условима индукованог оксидативног стреса нас- талог додатком терц-бутил-хидропероксида као спољног прооксиданса. Резултати су показали да сумпорни дериват, 4-бензимидазолил кумарин 5 има најизраженије анти- оксидативне особине (ОS –2,2), док халогеновани деривати пиразолил-кумарина 7 и 8 реагују као прооксиданси (ОS 2,7 и 2,0). Утицају додатог прооксиданса се најбоље опиру једињења 7 и 8. Испитивани деривати изокумарина и фталида такође показују проокси- дативне особине, док се оксидативном стресу најбоље опиру азолил-изокумарини (ОS < 0)

Common-sense legitimation of informal practices in present-day Serbia

As a part of a larger research within the Horizon 2020 project Closing the Gap Between Formal and Informal Institutions in the Balkans, 38 semi-structured interviews with citizens of Serbia have been conducted in the period July - October 2017. These comprise the database used for analysis of "narratives of informality" - stories of how the research participants legitimize (or rationalize) informal practices (using connections and acquaintances to "get things done", giving/receiving bribe, exchange of favors, etc.), supplemented by the analysis of participants’ attitudes towards informal practices, particularly when using them themselves. An insight into the respondents' ideas of informality was gained through describing and understanding doxa - beliefs of an individual as "a quasi-perfect correspondence between the objective order and the subjective principles of organization (with which) the natural and social world appear as self-evident" (Bourdieu) or senso comune (Gramsci) - "naturalized", unreflected, practical knowledge taking the form of self-explanatory content of common sense, that which is taken for granted, what "everybody knows", the knowledge of the world that is undisputed - "just the way it is", the domain of indefinite beliefs and incoherent views of the world, the knowledge which "legitimizes with the absence of legitimizing". The assumption is that the "quality" of doxa, in the sense of its positive or negative orientation, has a large impact on the possibility of changes in formal practices and procedures - in some cases serving as a stimulus for change, and as an obstacle to changes in others - situations in which the new/imported rules remain "empty shells" with little influence in social life

Automatic generation of decision tree algorithms for classification

Стабла одлучивања су врло распрострањен модел за класификацију, којом се описује начин како се може предвиђати класа неког објекта (нпр. добар/лош клијент, болестан, здрав пацијент, позитиван/негативан текст, итд) на основу доступних атрибута тих објеката...Decision trees are very popular classification model, which deskribes a way to predict classes of an object (e. g. good/bad client, silk/healthy patient, positive/negative text) based on available attributes of the given object..

Hermeneutics of Hans-Georg Gadamer and German Literature of the 19th Century

Doktorska disertacija pod naslovom Hermeneutika Hansa-Georga Gadamera i nemačka književnost 19. veka za svoj glavni predmet ima filozofsku hermeneutiku Hansa-Georga Gadamera, kao i tumačenje nemačke književnosti 19. veka na primeru Getea i Helderlina na teorijskim osnovama Gadamerove hermeneutike i savremenih hermeneutičkih teorija. Cilj rada je da pokaže šta i na koji način je kao jedna od glavnih delatno-povesnih instanci uticalo na formiranje Gadamerovog misaonog puta, kao i njegovog celokupnog hermeneutičkog zdanja. U disertaciji se isto tako razmatraju neki od osnovnih pojmova humanističke tradicije na kojima Gadamer gradi svoje hermeneutičko zdanje, zatim ontologija umetničkog dela i njene hermeneutičke implikacije, kao i mesto književnosti u takvoj ontologiji umetnosti i hermeneutici. Pitanje o književnosti, povesti i jeziku je centralno pitanje ove disertacije koje počinje pretresanjem predistorije Gadamerove i novije i savremene hermeneutike, nastavlja se razmatranjem osnovnih hermeneutičkih problema kao što su Hajdegerovo otkriće predstrukture razumevanja, princip povesti delovanja i stapanje horizonata i završava se analizom delatno-povesne svesti i značaja Hegelove i Platonove dijalektike za celinu Gadamerove hermeneutike i odgovorom na centralno pitanje ove disertacije. Završno poglavlje prvog dela disertacije posvećeno je filozofiji jezika u svetlu Gadamerove hermeneutike, ne samo zbog Gadamerovog zasnivanja univerzalnosti hermeneutike upravo u jeziku, već i zato što, prema našem shvatanju, jezik predstavlja najžilaviji pojavni oblik autoriteta koji, ukoliko nije ekspliciran u preliminarnoj fazi razumevanja, može da izvrši presudan, nesvesni uticaj na proces razumevanja i tumačenja duhovno-istorijskih fenomena, posebno književnosti kao pre svega jezičke umetnosti. Na kraju disertacije su zaključna razmatranja i spisak literature.The doctoral thesis entitled Hermeneutics of Hans-Georg Gadamer and German Literature of the 19th Century has as its main subject the philosophical hermeneutics of Hans-Georg Gadamer, as well as interpreting German literature of the 19th century on example of Goethe and Hölderlin based on the philosophical hermeneutics of Gadamer and contemporary hermeneutical theories. The purpose of the work is to show what and in which way as one of the main instances of „Wirkungsgeschichte“ influenced the formation of Gadamer’s way of thinking, as well as his entire hermeneutical edifice. The work also considers some of the basic terms of the tradition of humanities on which Gadamer builds his hermeneutical edifice, followed by the explication of ontology of work of art and its hermeneutical implications, as well as the place of literature in that ontology of art and hermeneutics. The question of literature, history and language is the central task of this doctoral work which begins with the explication of the prehistory of Gadamer’s new and contemporary hermeneutics, continues with questioning of some basic hermeneutical problems such as Heidegger’s discoveries of the prestructure of understanding, the principle of impact history and the merging of horizonts, and ends with the analysis of consciousness of impact history and the importance of Hegel’s and Plato’s dialectics for Gadamer’s hermeneutics in general and the answer of the central question of this doctoral work. The final chapter of the doctoral work first part is dedicated to the philosophy of language in the light of Gadamer’s hermeneutics, not only because of Gadamer’s defining the universality of hermeneutics in language, but also because, as we understand the issue, the language represents the most resilient appearance form of authority, which, if unexplicated in the preliminary phase of understanding, can decisively and unconceously impact the process of understanding and interpreting human-historical phenomena, especially literature as above all work of art made in language. The final chapter of the doctoral work consists of conclusions and list of used literature

Influence of national business environment on foreign direct Investments as an international marketing strategy

Aktuelnost i neophodnost strategijskog pristupa marketing aktivnostima i potreba afirmisanja intenzivnije i kompleksnije međunarodne orijentacije domaćih preduzeća, polazni su aspekti u okviru kojih su realizovani osnovni ciljevi disertacije. Svaka država pojedinim karakteristikama nacionalnog poslovnog okruženja postavlja okvire rasta, razvoja i načina poslovanja preduzeća na njenom području. Determinante ponašanja preduzeća mogu se delom vezivati za samo preduzeće, a drugim delom za opšte okolnosti i uslove poslovanja zemlje u kojoj ono funkcioniše. Uspešan ekonomski razvoj je proces sukcesivnog unapređenja načina funkcionisanja privrede i njenih strukturnih promena, u kom se nacionalno poslovno okruženje razvija da podrži i ohrabri sve sofisticiranije i produktivnije načine konkurisanja firmi lociranih u zemlji. Intenzivnije uključivanje domaćih preduzeća na međunarodno tržište nije moguće bez pojačane investicione aktivnosti. Zemlje sa ekonomskim performansama kakve karakterišu Srbiju, upućene su na SDI kao izvor investicionih sredstava. U postojećem privrednom ambijentu one su neophodne za strukturna prilagođavanja realnog sektora i podizanje njegove konkurentnosti, ali i za osavremenjavanje ponude raznovrsnih uslužnih delatnosti, u funkciji uspešnog sprovođenja strategije izvozno-orijentisanog privrednog rasta. Potrebno je, pre svega, prevazići probleme vezane za nedovoljno razumevanje značaja SDI, ali i realno sagledati njihove domete, strategijski upravljati njihovim tokovima i selektivno sagledavati kako konkretne investicije utiču na makro i mikroekonomskom nivou. Navedeno uslovljava i potrebu uspostavljanja transparentne veze i istraživanja značaja interakcija između nacionalnog poslovnog okruženja i uspešnosti strategije SDI. Dogradnjom pojedinih dimenzija poslovnog okruženja, neophodno je doći u situaciju da sve više ističemo svoje razvojne prioritete pred strane investitore. Takođe, na bazi formulisane strategijske vizije obezbediti odlučno delovanje na povećanje atraktivnosti nacionalne ekonomije, regiona i oblasti u njenom sastavu za nove SDI i pokretanje novog investicionog ciklusa koji će dovesti do rasta međunarodne konkurentnosti privrede, diversifikacije izvoza i novih investicionih tokova, kako ulaznih, tako i investicija domaćih preduzeća na inostranim tržištima. SDI kao strategija ulaska i poslovanja na inostranom tržištu, mogu biti katalizator razvoja ne samo za firmu investitora, već i za celu mrežu povezanih učesnika projekta.Actuality and necessity of a strategic approach to marketing activities, as well as a need to affirm a more intense and complex international orientation of domestic companies are the initial aspects in which the basic targets of the dissertation have been realized. Using individual features of national business environment, each country determines the limits of growth, development and companies’ business methods within its territory. Determinants of the corporate behaviour may be partially bound to the company itself, while the other part may refer to general circumstances and business conditions of the subject country. Successful economic development is a process of subsequent improvement of the economic functioning method and its structural changes, where national business environment is being developed to support and encourage increasingly ophisticated and productive ways in which the local companies compete. A more intense involvement of domestic companies in international market is not possible without a stronger investment activity. The countries having such economic performances as Serbia are related to FDI as the source of investment assets. In the existing economic environment, these are required for structural adjustments of real sector in order to increase its competitiveness, but also for modernisation of the offer of various services in order to successfully implement the strategy of the export-oriented economic growth. Before all, it is necessary to overcome the issues referring to insufficient comprehension of the FDI importance but also to realistically perceive their limits, to strategically manage their flows and to selectively perceive the influence of concrete investments both on macro and micro conomic levels. The above mentioned implies the need to establish a transparent relation and research referring to the importance of interactions between national business environment and success of the FDI strategy. It is necessary to upgrade individual dimensions of business environment in order to be in the situation to emphasize our development priorities to the foreign investors. Further, based on the formulated strategic vision, we are to ensure a decisive actions in order to make national economy, region and associated areas more attractive for new FDI; a new investment cycle is to be driven in order to rise international competitiveness of the economic, to diversify the exports and new investment flows referring to both incoming and outcoming investments. FDI as a strategy of entering and dealing on the foreign market may be a development catalyser not only for the investing company but also for the entire net of the related project participants

Bourdieu’s Theory and the Social Constructivism of Berger and Luckmann

The paper compares Pierre Bourdieu’s sociological approach with the one developed by Peter Berger and Thomas Luckmann. The aim of the paper is to identify the complementarities and incongruences of these approaches. The main similarity consists in the intention to “dialectically” overcome/bridge the gap between “objectivism” and “subjectivism” in social theory. Another parallel includes a negative attitude towards the relativistic tendencies of postmodernism. These authors share the thematization of: the body as a locus of social influences, the centrality of language in social life, the social functions of knowledge, and the importance of power in social relations. Differences in theorizing are attributed to the different intellectual, theoretical, and socio-cultural contexts in which these scientists operated. The divergences of these theoretical approaches become evident when one examines the different meaning and significance attached to the concepts of individuation, structure, action, habitus and habitualization, structure of relevance and relation of common-sense and scientific knowledge. Finally, there is a visible difference in political views: Bourdieu was a critic “from the left,” while Berger and Luckmann were self-proclaimed liberal conservatives.U radu se poredi sociološki pristup Pjera Burdijea sa onim koji su razvili Peter Berger i Tomas Lukman. Cilј rada je da se identifikuju komplementarnosti i razilaženja ovih pristupa. Glavna sličnost se sastoji u nameri da se „dijalektički” prevaziđe/premosti jaz između „objektivizma“ i „subjektivizma“ u društvenoj teoriji. Druga paralela uključuju negativan stav prema relativističkim tendencijama postmodernizma. Ono što je zajedničko za ove autore je tematizacija: tela kao mesta društvenih uticaja, centralnosti jezika u društvenom životu, društvenih funk cija znanja i značaja moći u društvenim odnosima. Razlike u teoretisanju se pripisuju različi tim intelektualnim, teorijskim i socio-kulturnim kontekstima u kojima su ovi naučnici delovali. Razilaženja ovih teorijskih pristupa postaju očigledna kada se ispita različito značenje i značaj koji se pridaje konceptima individuacije, strukture, delanja, habitusa i habitualizacije, strukture relevantnosti i odnosa zdravorazumskog i naučnog znanja. Konačno, vidljiva je razlika u političkim stavovima: Burdije je bio kritičar „s leva“, dok su Berger i Lukman bili samoproglašeni liberalni konzervativci

Synthesis of longamide B and rhamnolipid analogues and their physico-chemical and biological characterization

Ramnolipidi su ekološki prihvatljivi biosurfaktanti koje proizvodi bakterija Pseudomonas aeruginosa. Zbog interesantnog biološkog profila i odličnih fizičko-hemijskih svojstava nalaze primenu u biotehnologiji, bioremedijaciji i medicini. Njihova šira i ekonomski prihvatljivija primena je međutim značajno otežana činjenicom da se teško mogu dobiti u većim količinama i u čistoj formi. Kao posledica toga istraživanja u smeru strukturnih modifikacija i sinteze analoga ramnolipida nisu još uvek zaživela, samim tim, fizičko-hemijska i biološka svojstva srodnih molekula nisu još uvek dovoljno istražena. Imajuči u vidu neekonomičnost sinteze ramnolipida cilj ovog istraživanja bio je pronaći sintetski pristupačne molekule koji bi imali isti ili bolji biološki ili fizičko-hemijski profil od samih prirodnih ramnolipida. Korišćenjem (R)-3-hidroksikiseline kao osnovnog strukturnog fragmenta sintetisani su šećerni, heterociklični i peptidni analozi ramnolipida i ispitivane njihove fizičko-hemijske i antimikrobne osobine. Zamenom ramnoze drugim šećerima smanjuje se cena proizvodnje ovih molekula dok se istovremeno očuvava površinska aktivnost i biorazgradivost. Zamenom ramnoze peptidima dobijajena je serija jedinjenja sa anti-adhezivnim dejstvom na Candida albicans (BFIC50 = 4,5 μg/mL). Najaktivniji derivati su konjugati leucina i 3-hidroksikiselina koje sadrže benzil estar. SAR studijom je pokazano da je optimalan broj aminokiselina u bočnom nizu 1-2, kao i da se anti-biofilm aktivnost povećava sa produženjem alifatičnog niza 3-hidroksikiselina. Ova jedinjenja inhibiraju formiranje biofilma sprečavanjem adhezije C. albicans na abiotsku i biološku površinu. Pored ramnolipida, i mali molekuli koji pripadaju bromopirolskim alkaloidima takođe ispoljavaju antimikrobna i anti-biofilm svojstva. Longamid B je jedan od naistraživanijih molekula ove grupe. Poznata je njegova antimikrobna aktivnost na bakterijske sojeve Bacillus subtilis i Staphylococcus aureus. Iz tog razloga predstavlja atraktivan target za totalnu sintezu i šire proučavanje hemijskog prostora definisanog njegovom strukturom. Pretpostavljeno je da se osnovni skelet bromopirolskih alkaloida, može dobiti intramolekulskom nukleofilnom adicijom na alene. Ispitivanjem ciklizacionih reakcija aminoalena u prisustvu serije metalnih soli došlo se do optimalnih uslova koji su podrazumevali korišćenje stehiometrijske količine AgNO3. Zahvaljujući hiralnom ciklizacionom prekursoru reakcija ciklizacije se odvijala stereoselektivno. Razvijena metodologija iskorišćena je u sintezi longamida B i stilizina D. U cilju diverzifikacije strukture bromopirolskih alkaloida ispitivane su reakcije i karboaminacije aminoalena katalizovane paladijumom. Ova strategija omogućila je sintezu α-supstituisanih derivata longamida.Rhamnolipids are environmentally friendly biosurfactants produced mostly by strains of Pseudomonas aeruginosa. Due to their interesting biological profile and excellent physico-chemical properties, they find application in biotechnology, bioremediation and medicine. The inefficient large scale production, however, still hinders their wider application. Consequently, the research on structural modifications and the synthesis of rhamnolipid analogues is still in the early stages and the physico-chemical and biological properties of related molecules are not yet fully explored. Thus this research aimed to find synthetically accessible molecules which would mimic or enhance the properties of the parent molecule. Using (R)-hydroxy acids as a core building block, the sugar, heterocyclic and peptide analogues of rhamnolipids were synthesised and their physico-chemical and antimicrobial properties evaluated. Replacing rhamnose with other sugars allows for a reduction in production cost whilst preserving the surface active properties and biodegradability of the parent molecules. The replacement of rhamnose with peptides produced a series of molecules with anti-adhesion effect on Candida albicans (BFIC50 = 4,5 μg/mL). The most potent derivatives were conjugates of leucine and benzyl esters of 3-hydroxyacids. The SAR study showed that the optimal number of amino acids in the sidechain was one or two, furthermore, the elongation of the aliphatic chain also improved the anti-biofilm properties of the peptide derivatives. The compounds were found to exert anti-biofilm properties through inhibition of C. albicans adhesion to abiotic and biotic surfaces. Apart from rhamnolipids, small molecules, members of bromopyrrole alkaloid family, also exert antimicrobial and anti-biofilm properties. Longamid B is one of the most studied molecules of this group. Its antimicrobial activity against Bacillus subtilis and Staphylococcus aureus is well known. Therefore it represents an attractive target for total synthesis and the exploration of chemical space around the molecule. Our envisaged strategy was based on the hypothesis that the core structure of bromopyrrole alkaloids could be accessed via intramolecular nucleophilic addition to allene moiety. The investigation of cyclization reactions of aminoallenes in the presence of a series of metal salts uncovered a stoichiometric amount of AgNO3 as the best option for the reaction. The chiral precursor allowed a stereoselective cyclization process. The developed methodology was successfully applied in the synthesis of longamide B and stylisine D. With the aim of diversificating the structure of bromopyrrole alkaloids the carboamination reactions of aminoallenes catalyzed by palladium were also explored. This strategy allowed the synthesis of α-substituted derivatives of longamide B

Rijedak slučaj multifokalnog serpiginoidnog koroiditisa

Multifocal serpiginoid choroiditis is an infectious variety of serpiginous choroiditis. The disease is characterized by infectious etiology and overlapping clinical features in an intermediary form of acute posterior multifocal placoid pigment epitheliopathy and serpiginous choroiditis. In a 33-year-old patient, bilateral multiple placoid partially confluent chorioretinal lesions were diagnosed after a febrile flu-like episode. On the right eye, there was a progressive decrease in visual acuity. Later, the lesions had a prolonged progressive devastating clinical course and widespread distribution of placoid lesions, and took the form of serpiginoid choroiditis. We conducted extensive laboratory work-up and ancillary investigation for granulomatous diseases such as tuberculosis and sarcoidosis, and the results were not consistent with these entities. Systemic medical work-up revealed a history of exposure to the human immunodeficiency virus, herpes simplex virus 1, varicella zoster virus and cytomegalovirus. The titer of Mycoplasma pneumoniae IgM antibodies was positive. After serological analysis positive for Mycoplasma pneumoniae, systemic antibiotic therapy and anti-inflammatory doses of corticosteroids were administered. Improvement of visual acuity after the introduction of causal antibiotic therapy in combination with anti-inflammatory therapy confirmed our suspicion that Mycoplasma pneumoniae was the etiologic cause of multifocal serpiginoid choroiditis.Multifokalni serpiginoidni koroiditis je infektivna varijanta serpiginoznog koroiditisa. Bolest obilježava infektivna etiologija i preklapanje kliničke slike između akutnog oblika stražnje multifokalne plakoidne pigmentne epiteliopatije i serpiginoznog koroiditisa. Nakon epizode poput febrilne gripe bolesniku u dobi od 33 godine dijagnosticirane su bilateralne, brojne, plakoidne, djelomice konfluentne korioretinalne lezije. Na desnom oku vidna oštrina se progresivno smanjivala. Kasnije su lezije poprimile prolongirani, progresivni, razarajući klinički tijek i raširenu distribuciju plakoidnih lezija u obliku serpiginoidnog koroiditisa. Proveli smo opsežne laboratorijske testove i pomoćnu dijagnostiku za granulomatozne bolesti poput tuberkuloze i sarkoidoze, ali rezultati nisu potvrdili uzročnika. Daljnja sistemska medicinska obrada je pokazala povijest izlaganja virusu humane imunodeficijencije, herpes simpleksu, varičela zoster virusu i citomegalovirusu. Povišen je bio titar IgM antitijela na Mycoplasma pneumoniae. Nakon pozitivnih seroloških analiza na Mycoplasma pneumoniae primijenjena je sistemska antibiotska terapija i protuupalna doza kortikosteroida. Poboljšanje vidne oštrine nakon uvođenja uzročne antibiotske terapije u kombinaciji s protuupalnom terapijom potvrdilo je našu sumnju da je Mycoplasma pneumoniae bila etiološki uzročnik multifokalnog serpiginoidnog koroiditisa

Franck-Condon factors and observed band strength distribution in the vibrational structure of the Ag_2 D-X band system

Potential curves for the X_1Σ_g^+ and D_1Σ_u^+ states of three diatomic silver isotopomers, ^(107)Ag_2, ^(107)Ag^(109)Ag and ^(109)Ag_2, were determined from the best available molecular constants by the Rydberg-Klein-Rees method. From these potentials, Franck-Condon factors and band-origin wave numbers were computed, and the reliability of the obtained values was verified by comparison with the observed band strength distribution and the measured band origin positions in a previously recorded D-X spectrum. The ratios of the Franck-Condon factors to those of corresponding isotopic bands were found to be very close to unity, revealing only a very small isotopic effect on the Franck Condon factors of Ag_2 D-X bands. The isotopic shifts of the calculated band origins agree well with previously measured displacements of band heads