926 resultados para Grob fragmentation


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Abstract Bovine Spongiform Encephalopathy (BSE) is a virulent disease which may infect by affecting the central nervous system (CNS) tissues in cattle and causes degeneration in nerves. Central nervous system tissues such as brain and spinal cord which are classified as specified risk materials (SRMs) are regarded to be main source of infection. The contamination of the meat with the specific risk materials (SRMs) can occur in phases of slaughter, fragmentation of carcass and processing. This study was conducted in order to investigate the existence of CNS tissues in raw meat ball (cig kofte) which is commonly consumed in the Southeastern Region of Turkey, particularly in Şanlıurfa. For this purpose, 145 samples of raw meat ball were tested. The enzyme-linked immunosorbent assay (ELISA) kits (Ridascreen risk material 10/5, R-biofarm GmbH) which determine glial fibrillary acidic protein (GFAP) as determinant were used. As a result of the analyses, positivity was detected in 21 of totally 145 samples of raw meat ball (14.48%). 6 (4.14%) of the samples gave low level of positivity (≥ 0.1 standard absorbance), 10 (6.90%) gave medium level of positivity (>0.2 standard absorbance) and 5 (3.45%) gave high level of positivity (≥0.5 standard absorbance). As a consequence, meats are contaminated in any phase of both slaughter and meat production even if accidentally. Regarding this matter, necessary measures should be taken and hygiene rules should be applied.

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The thesis explores how the business ecosystem of financial services has changed and what its drivers of change are. Existing literature in the field of financial industry is concerned with financial innovations and their features, determinants and factors, but also with how to organize innovation activities such as open innovation principles. Thus, there is a clear need for understanding changes in financial service ecosystem. First, the comprehensive theory framework is conducted in order to serve the reader’s necessary understanding of basic theoretical concepts that are related to ecosystem changes. Second, the research is carried out by using qualitative research methods; the data is collected by interviewing 11 experts from the field of financial services in Finland. According to the results of this thesis, the most significant changes in the financial service ecosystem are the new market players. They have increased competition, created new courses of action, set new requirements for financial services, and first and foremost, they have shifted customers into the heart of the whole ecosystem. These new market players have a willingness to cooperate with external partners, which means a shift towards the world of open innovation. In addition, the economic environment has changed which has resulted in tighter regulation for incumbents making them even unyielding. Technology change, together with digitalization, has lead new financial innovations and new digital service channels, which have challenged the traditional business models in the financial industry. They have improved transparency, openness and efficiency, but also lead to the fragmentation of financial services. Thus, customers search for financial services from different sources and different service providers, and finally combine them into a coherent whole, which meets their own needs. The change of customers’ behavior and social environment has enabled and boosted these changes in the financial ecosystem. All in all, the change of the financial ecosystem is not a result of one or a few change forces, but instead it is a combination of many different factors.

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Cleavages have been central in understanding the relationship between political parties and voters but the credibility of cleavage approach has been increasingly debated. This is because of decreasing party loyalty, fewer ideological differences between the parties and general social structural change amongst other factors. By definition, cleavages arise when social structural groups recognize their clashing interests, which are reflected in common values and attitudes, and vote for parties that are dedicated to defend the interests of the groups concerned. This study assesses relevance of cleavage approach in the Finnish context. The research problem in this study is “what kind of a cleavage structure exists in Finland at the beginning of the 21st century? Finland represents a case that has traditionally been characterized by a strong and diverse cleavage structure, notable ideological fragmentation in the electorate and an ideologically diverse party system. Nevertheless, the picture of the party-voter ties in Finland still remains incomplete with regard to a thorough analysis of cleavages. In addition, despite the vast amount of literature on cleavages in political science, studies that thoroughly analyze national cleavage structures by assessing the relationship between social structural position, values and attitudes and party choice have been rare. The research questions are approached by deploying statistical analyses, and using Finnish National Election Studies from 2003, 2007 and 2011as data. In this study, seven different social structural cleavage bases are analyzed: native language, type of residential area, occupational class, education, denomination, gender and age cohorts. Four different value/attitudinal dimensions were identified in this study: economic right and authority, regional and socioeconomic equality, sociocultural and European Union dimensions. This study shows that despite the weak overall effect of social structural positions on values and attitudes, a few rather strong connections between them were identified. The overall impact of social structural position and values and attitudes on party choice varies significantly between parties. Cleavages still exist in Finland and the cleavage structure partly reflects the old basis in the Finnish party system. The cleavage that is based on the type of residential area and reflected in regional and socioeconomic equality dimensions concerns primarily the voters of the Centre Party and the Coalition Party. The linguistic cleavage concerns mostly the voters of the Swedish People’s Party. The classic class cleavage reflected in the regional and socioeconomic equality dimension concerns in turn first and foremost the blue-collar voters of the Left Alliance and the Social Democratic Party, the agricultural entrepreneur voters of the Centre Party and higher professional and manager voters of the Coalition Party. The conflict with the most potential as a cleavage is the one based on social status (occupational class and education) and it is reflected in sociocultural and EU dimensions. It sets the voters of the True Finns against the voters of the Green League and the Coalition Party. The study underlines the challenges the old parties have met after the volatile election in 2011, which shook the cleavage structure. It also describes the complexity involved in the Finnish conflict structure and the multidimensionality in the electoral competition between the parties.

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The purpose of this Master’s thesis was to study customer knowledge transfer processes in multinational corporations (MNCs). The main objective was to examine how customer knowledge is transferred in MNCs and what kind of factors enhance or inhibit the knowledge transfer process, and to create a framework on the basis of the existing literature and the empirical findings. In this thesis the factors were organized according to whether they are properties of the unit involved in knowledge management, properties of relationships between the units or properties of the knowledge itself. There are various properties that influence knowledge transfer but in this thesis the focus was on examining the relevant findings from the customer knowledge viewpoint. Empirical results show that internal fragmentation in the MNC seems to be inherent in this type of organization, and may cause many problems in customer knowledge transfer and utilization. These knowledge transfer inhibitors rise from the organization’s properties: it’s absorptive capacity, motivation, organizational culture, and the two dimensions of knowledge. However, in spite of the inherent forces causing internal fragmentation and inhibiting knowledge transfer, moderate customer knowledge and expertise codification, cooperative working practices among the experts, and socialization mechanisms posed by the headquarters seem to help maintain customer knowledge transfer, and value creation in the long-term relationship. This value creation can be seen to be based on accessing and integrating a wide variety of knowledge resources in order to create a coherent product and service offering.

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The pearl millet seed is small and its size varies, making sowing more difficult. The pelleting technique increases and homogenizes seed size, but it is essential to determine the physical and physiological characteristics of pelleted seeds. The physiological analysis consisted of: first germination count, final germination, speed emergence index, and seedling emergence. Physical analysis consisted of determining the 1000-seed weight, 1000-seed volume and fragmentation. The control treatment did not receive any coating, and the other 36 treatments combined four binders: bentonite, polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP) and methyl cellulose (Methocel®), and nine powder coating products: microcellulose, plaster, vermiculite, magnesium thermophosphate (Yoorin®), phytic acid, dicalcium phosphate, super simple phosphate (SS), monoamonic phosphate (MAP) and reactive phosphate. Among the materials used to form the pearl millet pellet, the most efficient binders were the polyvinyl acetate and the methyl cellulose, and as coaters, the vermiculite and the microcellulose.

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The supersweet (Sh2) corn seeds have a thin tegument and an irregular shape, which hinder the sowing procedure. As a function of those factors, the significance of using the pelleting process to improve sowing and standardize the stand of plants in the field without the need of thinning within the row is emphasized. Although this technique has already been known for many years, little has been studied on the effect of such procedure on the plantability and on the moisture content of the supersweet corn seeds. Therefore, this research work aimed at evaluating the effects of pelleting on the moisture content of the seeds along the storing process, on the occurrence of gaps on seed deposition and on the dropping of double seeds, with the aid of a testing seeder. Other physical attributes of seeds and pellets were also evaluated through tests of fragmentation, screen retention, mass of a thousand seeds and apparent volume. Results have shown an increase on the mass and on the volume of the pelleted seeds that presented highly resistance to cracks and breaking. The pelleting was efficient on the reduction of gaps and on the deposition of double seeds at sowing, thus providing highly satisfactory results for these attributes. An increase on the seed moisture content was also observed as a function of storage with a significant reduction on this factor after the pelleting procedure. Results allow concluding that the pelleting process reduces seed moisture content and improves plantability, positively affecting the efficiency of the sowing process.

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Global finance, combining offshore banking and universal banks to drive a broader globalization process, has transformed the modus operandi of the world economy. This requires a new "meta-economic" framework in which short-term portfolio-investment flows are treated as the dominant phenomenon they have become. Organized by global finance, these layered bi-directional flows between center and periphery manage a tension between financial concentration and monetary fragmentation. The resulting imbalances express the asymmetries built into that tension and render the exchange rate a more strategic policy variable than ever.

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Työn alustavana tavoitteena oli havaita yrityksen ict-ryhmässä käytettävien teknisten välineiden, informaation hallinnan järjestelmien ja ryhmän työtilojen vaikutus hiljasen tiedon jakamiseen tai sen estymiseen. Työssä tarkasteltiin myös vaikutusta ryhmän oppimiseen sekä ryhmään muodostuvan hiljaisen tiedon syntymisen ja henkilöitymisen syihin sekä hiljaisen tiedon laatuun. Lisäksi työssä pyritään löytämään tapoja, joiden avulla hiljaista tietoa voidaan hyödyntää ja jakaa ryhmässä siten että se mahdollistaa myös ryhmän oppimisen. Haastatteluissa nousivat esiin informaation hallintaongelmat, jotka johtuvat informaation hajautumisesta informaation eri hallinta järjestelmiin, tietoturvamääräysten aiheuttamiin esteisiin ja kriittisen teknisen dokumentaation tallentamiseen. Nämä vaikeuttavat tallennetun informaation hyödyntämistä ict-ryhmässä. Tämä osaltaan aiheuttaa hiljaisen tiedon henkilöitymistä ryhmässä ja hiljaisen tiedon jakamisen menetelmien jää hyödyntämättä. Haastatteluissa osoittautui, että hiljaisen tiedon hyödyntämisongelmat johtuvat osittain ryhmän sisäisten yhteyksien verkoston rakenteesta. Vahvojen linkkien vähyys ryhmässä ja vahvojen linkkien suuntautuminen ryhmän ulkoisiin verkostoihin vaikeuttaa hiljaisen tiedon siirtymistä ryhmässä ja aiheuttaa hiljaisen tiedon henkilöitymistä. Kiire todettiin ryhmän kannalta ongelmalliseksi hiljaisen tiedon jakamisen ja hyödyntämisen esteeksi. Tiedon adaptaatioon ja omaksumiseen liittyvät ongelmat ovat sidoksissa aikaan ja hiljaisen tiedon henkilöitymiseen ryhmässä. Ryhmätyö ja ryhmän päivittäisessä toiminnassa käytettävissä olevat hiljaisen tiedon jakamisen menetelmät osoittautuvat sopivimmiksi edistämään ryhmän yhteistyökykyä sekä sosiaalisen rakenteen ja luottamuksen kehittymistä. Ne poistavat myös tiedon omaksumisen ja adaptaation esteitä. Ryhmätyö vaikuttaa myönteisesti ryhmän kollektiiviseen osaamiseen ja ryhmän hiljaisen tiedon kehittymiseen. Lisäksi se parantaa teknisen dokumentaation ymmärrettävyyttä.

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The research on the interaction between radiation and biomolecules pro-vides valuable information for both radiobiology and molecular physics. While radiobiology is interested in the damage inflicted on the molecule upon irradiation, molecular physics exploits these studies to obtain infor-mation about the physical properties of the molecule and the quantum me-chanical processes involved in the interaction. This thesis work investigated how a small change in the structure or composition of a biomolecule changes the response of the molecule to ioniz-ing radiation. Altogether eight different biomolecules were studied: nucleo-sides uridine, 5-methyluridine and thymidine; amino acids alanine, cysteine and serine; and halogenated acetic acids chloro- and bromoacetic acids. The effect of ionizing radiation on these molecules was studied on molecular level, investigating the samples in gas phase. Synchrotron radiation of VUV or soft x-ray range was used to ionize sample molecules, and the subsequent fragmentation processes were investigated with ion mass spectroscopy and ion-ion-electron coincidence spectroscopy. The comparison between the three nucleosides revealed that adding or removing a single functional group can affect not only the bonds from which the molecule ruptures upon ionization but also the charge localiza-tion in the formed fragments. Studies on amino acids and halogenated acetic acids indicated that one simple substitution in the molecule can dramatical-ly change the extent of fragmentation. This thesis work also demonstrates that in order to steer the radiation-induced fragmentation of the molecules, it is not always necessary to alter the amount of energy deposited on the molecules but selecting a suitable substitution may suffice.

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This thesis examines Death of a Ghost (1934), Flowers for the Judge (1935), Dancers in Mourning (1937), and The Fashion in Shrouds (1938), a group of detective novels by Margery Allingham that are differentiated from her other work by their generic hybridity. The thesis argues that the hybrid nature of this group of Campion novels enabled a highly skilled and insightful writer such as Allingham to negotiate the contradictory notions about the place of women that characterized the 1930s, and that in dOing so, she revealed the potential of one of the most popular and accessible genres, the detective novel of manners, to engage its readers in a serious cultural dialogue. The thesis also suggests that there is a connection between Allingham's exploration of modernity and femininity within these four novels and her personal circumstances. This argument is predicated upon the assumption that during the interwar period in England several social and cultural attitudes converged to challenge long-held beliefs about gender roles and class structure; that the real impact of this convergence was felt during the 1930s by the generation that had come of age in the previous decade-Margery Allingham's generation; and that that generation's ambivalence and confusion were reflected in the popular fiction of the decade. These attitudes were those of twentieth-century modernity--contradiction, discontinuity, fragmentation, contingency-and in the context of this study they are incorporated in a literary hybrid. Allingham uses this combination of the classical detective story and the novel of manners to examine the notion of femininity by juxtaposing the narrative of a longstanding patriarchal and hierarchical culture, embodied in the image of the Angel in the House, with that of the relatively recent rights and freedoms represented by the New Woman of the late nineteenth-century. Pierre Bourdieu's theory of social difference forms the theoretical foundation of the thesis's argument that through these conflicting narratives, as well as through the lives of her female characters, Allingham questioned the Hsocial myth" of the time, a prevailing view that, since the First World War, attitudes toward the appropriate role and sphere of women had changed.

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The fragmentation processes in the mass spectra of a series of organophosphorus, organochlorine, thio and dithiocarbamate as well as a number of miscellaneous pesticides have been studied i n detail by using the Bendix timeof- flight, MS-12 single-focussing and MS-30 double-focussing mass spectrometers. Interpretation of all the spectra have been presented; their mode s of dissociation elucidated, aided by metastable transitions wherever possible and the structures of the various f ragmentation species postulated wherever f easible. The fragmentation mechanisms are based on the concepts of inductive, resonance and steric ef~ects. Multiple bond cleavages accompanied by simultaneous bond formation and rearrangement reactions involving cycli c t r ansition states have clarified t he formation of various ions . Due emphasis has been placed on the effect of the functional groups or substituents in altering the mass spectral behaviour of the pesticides as they form the basis for the identifi cation of the otherwise identical pesticides. The organophosphorus pesticides which have been studied include i) the phosphates (eg: DDVP and Phosdrin ); ii) phosphorothionates (eg: Parathion, 0-2, 4 dichloro phenyl 0, O-diethyl thionophosphate); iii) phosphorothioites (eg: Tributyl phosphorotrithioite); i V) phosphorothioates (eg: Ethion) and v) phosphorodithioates (eg: Carbophenolthion). Cleavages and rearrangements of the ester moiety dominate the spectrum of phosdrin while that of DDVP is + dominated by t he fragmentation modes of the (OH30)2P=0 + moiety. Fragmentation §f the (CH30)2P=S characterises the spectrum of (OH30)2"P -Cl while cleavages of the + (C2H50 )2P=S species mark the spectra of parathion and 0-2, 4- di chlorophenyl O, O-diethyl thiophosphate. The 0(, cl eavages of the thioether f unction rather than + cleavages of the (C2H50)2P=S signify the spectrum of carbophenolthion. Tributyl phosphorotrithioite behaves more like an aliphatic hydrocarbon than like the corresponding phosphites. The isopropyl and butyl esters of 2, 4 dichlorophenoxy acetic acid show cleavage and rearrangement ions typical of an ester. In spite of its structural similari ty to pp' - DDT and pp' - DDD, Kalthane has a completely different mass spectral behaviour due to the influence of its hydroxyl function. The thiocarbamate pesticides studied include Eptam and Perbulate. Both are structurally similar but having different alkyl substituents on nitrogen and sulphur. This structurQlsimilarity leads to similar types of (N-C), (O-S) and (S-alkyl cleavages). However, perbulate differs from Eptam in showing a rearrangement ion at mle 161 and in forming an isocyanate ion as the base peak. In Eptam the base peak i s the alkyl ion. The dithiocarbamate, Vegadex, resembles the thiocarbamates in undergoing simple cleavages but it differs from them in having a weak parent ion; in the formation of its base peak and in undergoing a series of rearrangement reactions. The miscellaneous pesticides studied include 1-Naphthalene acetic aCid- methyl ester, Fiperonyl butoxide and Allethrin. The ester i s stable to electron impact and shows only fewer ions. Piper onyl butoxide, a polyether, shows characteristics of an et her, alcohol and aldehyde . Allethrin is regarded as an ester of the type R-C-O-R1 with n R being a substituted cyclopr opane moiety and o Rt, a substituted cyclopentenone mOiety. Accordingly it shows cleavage ions typical of an aliphatic ester and undergoes bond ruptures of the cyclic moieties to give unusual ions. Its base peak is an odd electron ion, quite contrary to expectations.

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The fragmentation patterns and mass spectra of some phenyl tin and -lead halide adducts with hexamethylphosphoramide are compared by subjecting them t~ electron impact and fast atom bombardment ionization in a mass spectrometer. This comparison is restricted to the metal-containing ions. Ligand-exchange mechanisms of some of the metal-containing species are explored by FAB-MS. Several moisturesensitive organo-metallics and H-bonded systems have been examined by FAB for attempted characterization, but without any success. Scavenging and trapping of water molecules by complex aggregates in solutions of quaternary ammonium fluorides and hydroxides are investigated by FAB to complement previous NMR-studies.

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Both El MS and FAB MS behavior of two groups of compounds, aryltin and ferrocene compounds, have been studied. For the aryltin compounds, the effect of substituent group position, substituent group type and ligand type on the El spectra have been explored in the El MS studies. The fragmentation mechanism has been investigated under El with linked scans, such as fragment ion scans(BJE), parent ion scans(B2JE) and constant neutral radical loss scans(B2(1-E)JE2). In the FAB MS studies, matrix optimization experiments have been carried out. The positive ion FAB MS studies focused on the effect of substituent group position, substituent group type and ligand type on the spectra. The fragmentation mechanisms of all the samples under positive ion FAB have been studied by means of the linked scans. The CA positive ion FAB fragmentation studies were also carried out for a typical sample. Negative ion FAB experiments of all the compounds have been done. And finally, the comparison of the El MS and FAB MS has been made. For ferrocenes, the studies concentrated on the fragmentation mechanism of each compound under El with linked scan techniques in the first field-free region and the applicability of positive/negative ion FAB MS to this group of compounds. The fragmentation mechanisms under positive ion FAB of those ferrocenes which can give positive ion FAB MS spectra were studied with the linked scan techniques. The CA +ve F AB fragmentation studies were carried out for a typical sample. Comparison of the E1 MS and FAB MS has been made.

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Linear alkylbenzenes, LAB, formed by the Alel3 or HF catalyzed alkylation of benzene are common raw materials for surfactant manufacture. Normally they are sulphonated using S03 or oleum to give the corresponding linear alkylbenzene sulphonates In >95 % yield. As concern has grown about the environmental impact of surfactants,' questions have been raised about the trace levels of unreacted raw materials, linear alkylbenzenes and minor impurities present in them. With the advent of modem analytical instruments and techniques, namely GCIMS, the opportunity has arisen to identify the exact nature of these impurities and to determine the actual levels of them present in the commercial linear ,alkylbenzenes. The object of the proposed study was to separate, identify and quantify major and minor components (1-10%) in commercial linear alkylbenzenes. The focus of this study was on the structure elucidation and determination of impurities and on the qualitative determination of them in all analyzed linear alkylbenzene samples. A gas chromatography/mass spectrometry, (GCIMS) study was performed o~ five samples from the same manufacturer (different production dates) and then it was followed by the analyses of ten commercial linear alkylbenzenes from four different suppliers. All the major components, namely linear alkylbenzene isomers, followed the same elution pattern with the 2-phenyl isomer eluting last. The individual isomers were identified by interpretation of their electron impact and chemical ionization mass spectra. The percent isomer distribution was found to be different from sample to sample. Average molecular weights were calculated using two methods, GC and GCIMS, and compared with the results reported on the Certificate of Analyses (C.O.A.) provided by the manufacturers of commercial linear alkylbenzenes. The GC results in most cases agreed with the reported values, whereas GC/MS results were significantly lower, between 0.41 and 3.29 amu. The minor components, impurities such as branched alkylbenzenes and dialkyltetralins eluted according to their molecular weights. Their fragmentation patterns were studied using electron impact ionization mode and their molecular weight ions confirmed by a 'soft ionization technique', chemical ionization. The level of impurities present i~ the analyzed commercial linear alkylbenzenes was expressed as the percent of the total sample weight, as well as, in mg/g. The percent of impurities was observed to vary between 4.5 % and 16.8 % with the highest being in sample "I". Quantitation (mg/g) of impurities such as branched alkylbenzenes and dialkyltetralins was done using cis/trans-l,4,6,7-tetramethyltetralin as an internal standard. Samples were analyzed using .GC/MS system operating under full scan and single ion monitoring data acquisition modes. The latter data acquisition mode, which offers higher sensitivity, was used to analyze all samples under investigation for presence of linear dialkyltetralins. Dialkyltetralins were reported quantitatively, whereas branched alkylbenzenes were reported semi-qualitatively. The GC/MS method that was developed during the course of this study allowed identification of some other trace impurities present in commercial LABs. Compounds such as non-linear dialkyltetralins, dialkylindanes, diphenylalkanes and alkylnaphthalenes were identified but their detailed structure elucidation and the quantitation was beyond the scope of this study. However, further investigation of these compounds will be the subject of a future study.

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The mass spectra of compounds of t he series (C6F5 )3-n MP~ (n = 1,2,3, M = P and As ), (C6F5>3Sb, Ph) Sb and (C6F5 )2SbPh have been studied in detail and the important modes of fragmentation were e1ucidated, a ided by metastable ions. Various trends attributed to the central atom and or the . substituent groups have been noted and, where applicable, compared to recent studies on related phenyl and pentafluorophenyl compounds of groups IV and V. The mass spectra of fluorine containing organometallic compounds exhibit characteristic migrations of fluorine to t he central atom, giving an increasing abundance of MF+, MF2+' and RMF+ (R = Ph or C6F5) ions on descending the group_ The mass spectra of pentafluorophenyl , antimony, and arsenic compounds show a greater fragmentation of the aromatic ring than those of phosphorus. The mixed phenyl pentafluorophenyl derivatives show a characteristic pattern depending on the number of phenyl grm.lps present but show t he general characteristics of both the tris(phenyl) and tris(pentafluorophenyl) compounds. The diphenyl pentafluorophenyl der ivatives show the loss of biphenyl ion as the most import ant step, the los s of phenyl t o give the i on PhMC6F5 + being of secondary importance. The ,bis(pentafluorophenyl) phenyl derivatives fragment primarily by loss of PhC6F5 to give C6F5M+ ions, the abundance of t hese increasing r apidly from phosphorus to arsenic. This species then, exhibits a characteristic fragmentation observed in the tris(penta- fluorophenyl ) compounds. However, the abundance of (C6F5)2M+ species in these compounds i s small. I ons of the type C6H4MC6F4 + and tetrafluorobiphenylene ions C6H4C6F4 + also are observed on substitution of a phenyl group for a penta- fluorophenyl group. The fully fluorinated species (C6F4)2M+ is not observed, although octafluorobiphenylene ions , (C6F4)2+' are evident in several spectra . The appearance potentials of the major ions were obtatned from the ionisation efficiency curves. Attempts were made to correlate these to the effect of the central atom in substituent groups, but the large errors involved prevented the reaching of quantitative conclusions, although it would appear that the electron is removed from the ligand in the ionisation of t he parent molecule .