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1.
Food Chem ; 340: 127906, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32890857

RESUMO

Wine quality and character are defined in part by the terroir in which the grapes are grown. Metabolomic techniques, such as nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma mass spectrometry (ICP-MS), are used to characterise wines and to detect wine fraud in other countries but have not been extensively trialled in Australia. This paper describes the use of ICP-MS and NMR to characterise a selection of Pinot noir wines. Wines from varying terroirs could be somewhat distinguished by their mineral content using principal component analysis (PCA). PCA was able to separate wines by their Australian states more clearly than by region. Metabolomic analysis of the wines using NMR did not find any correlations with climate/daytime temperatures, or region. An analysis of coinertia suggested that the two datasets were not redundant, and it is proposed that ICP-MS data is the most useful for determining regionality.


Assuntos
Análise de Alimentos/métodos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Vinho/análise , Austrália , Clima , Análise de Alimentos/estatística & dados numéricos , Metabolômica , Nova Zelândia , Análise de Componente Principal , Temperatura , Vitis/química , Vitis/metabolismo
2.
Molecules ; 25(11)2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32466472

RESUMO

The Woodburytype is a 19th century photomechanical technique capable of producing high-quality continuous-tone prints. It uses pigment dispersed in gelatin to produce a 2.5D print, in which the effect of varying tone is produced by a variation in the print height. We propose a method of constructing full colour prints in this manner, using a CMY colour model. This involves the layering of multiple translucent pigmented gelatin films and tracking how the perceived colour of these stacks changes with varying height. A set of CMY inks is constructed, taking into account the optical properties of both the pigment and gelatin, and a method of translating images into these prints is detailed.


Assuntos
Gelatina/química , Fotografação/métodos
3.
EMBO J ; 37(11)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29661886

RESUMO

Increasing evidence suggests that synaptic functions of the amyloid precursor protein (APP), which is key to Alzheimer pathogenesis, may be carried out by its secreted ectodomain (APPs). The specific roles of APPsα and APPsß fragments, generated by non-amyloidogenic or amyloidogenic APP processing, respectively, remain however unclear. Here, we expressed APPsα or APPsß in the adult brain of conditional double knockout mice (cDKO) lacking APP and the related APLP2. APPsα efficiently rescued deficits in spine density, synaptic plasticity (LTP and PPF), and spatial reference memory of cDKO mice. In contrast, APPsß failed to show any detectable effects on synaptic plasticity and spine density. The C-terminal 16 amino acids of APPsα (lacking in APPsß) proved sufficient to facilitate LTP in a mechanism that depends on functional nicotinic α7-nAChRs. Further, APPsα showed high-affinity, allosteric potentiation of heterologously expressed α7-nAChRs in oocytes. Collectively, we identified α7-nAChRs as a crucial physiological receptor specific for APPsα and show distinct in vivo roles for APPsα versus APPsß. This implies that reduced levels of APPsα that might occur during Alzheimer pathogenesis cannot be compensated by APPsß.


Assuntos
Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Cognição/fisiologia , Plasticidade Neuronal/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Neurônios/patologia , Coluna Vertebral/metabolismo , Coluna Vertebral/patologia , Transmissão Sináptica/genética , Receptor Nicotínico de Acetilcolina alfa7/genética
4.
Dev Sci ; 20(6)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27747974

RESUMO

Sleep is considered to support the formation of skill memory. In juvenile but not adult song birds learning a tutor's song, a stronger initial deterioration of song performance over night-sleep predicts better song performance in the long run. This and similar observations have stimulated the view of sleep supporting skill formation during development in an unsupervised off-line learning process that, in the absence of external feedback, can initially also enhance inaccuracies in skill performance. Here we explored whether in children learning a motor sequence task, as in song-learning juvenile birds, changes across sleep after initial practice predict performance levels achieved in the long run. The task was a serial reaction time task (SRTT) where subjects had to press buttons which were lighted up in a repeating eight-element sequence as fast as possible. Twenty-five children (8-12 years) practised the task in the evening before nocturnal sleep which was recorded polysomnographically. Retrieval was tested on the following morning and again 1 week later after daily training on the SRTT. As expected, changes in response speed over the initial night of sleep were negatively correlated with final performance speed after the 1-week training. However, unlike in song birds, this correlation was driven by the baseline speed level achieved before sleep. Baseline-corrected changes in speed or variability over the initial sleep period did not predict final performance on the trained SRTT sequence, or on different sequences introduced to assess generalization of the trained behaviour. The lack of correlation between initial sleep-dependent changes and long-term performance might reflect that the children were too experienced for the simple SRTT, possibly also favouring ceiling effects in performance. A consistent association found between sleep spindle activity and explicit sequence knowledge alternatively suggests that the expected correlation was masked by explicit memory systems interacting with skill memory formation.


Assuntos
Comportamento Infantil/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Sono/fisiologia , Afeto , Análise de Variância , Criança , Feminino , Humanos , Conhecimento , Masculino , Rememoração Mental/fisiologia , Polissonografia , Tempo de Reação/fisiologia , Vigília
5.
Langmuir ; 32(20): 5085-93, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27119202

RESUMO

Using experiments and molecular dynamics simulations, we explore magnetic field-induced phase transformations in suspensions of nonmagnetic rodlike and magnetic sphere-shaped particles. We experimentally demonstrate that an external uniform magnetic field causes the formation of small, stable clusters of magnetic particles that, in turn, induce and control the orientational order of the nonmagnetic subphase. Optical birefringence was studied as a function of the magnetic field and the volume fractions of each particle type. Steric transfer of the orientational order was investigated by molecular dynamics (MD) simulations; the results are in qualitative agreement with the experimental observations. By reproducing the general experimental trends, the MD simulation offers a cohesive bottom-up interpretation of the physical behavior of such systems, and it can also be regarded as a guide for further experimental research.

6.
Psychother Res ; 26(4): 500-10, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26218673

RESUMO

OBJECTIVE: A Psychotherapy Process Q-set (PQS) prototype characteristic of short-term psychodynamic therapy (STPP) does not yet exist. METHOD: Experts in supportive-expressive (SE) therapy used the 100-Item PQS questionnaire to rate an ideal short-term SE therapy. RESULTS: Agreement between raters was high (Cronbach's alpha = 0.94). The prototype for SE therapy showed a significant correlation with the psychoanalytic prototype, but with 28% of variance explained, the majority of variance of the former was not explained by the latter or vice versa. Furthermore, the SE prototype showed significant correlations with the cognitive-behavioral prototype and the prototype of interpersonal therapy by Ablon and Jones (r = 0.69, 0.43). CONCLUSIONS: We recommend using the PQS prototype presented here for future process research on STPP.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Terapia Psicanalítica/métodos , Processos Psicoterapêuticos , Psicoterapia Psicodinâmica/métodos , Psicoterapia Psicodinâmica/normas , Adulto , Humanos
7.
Psychother Psychosom ; 84(3): 129-48, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25833321

RESUMO

BACKGROUND: The Task Force on Promotion and Dissemination of Psychological Procedures proposed rigorous criteria to define empirically supported psychotherapies. According to these criteria, 2 randomized controlled trials (RCTs) showing efficacy are required for a treatment to be designated as 'efficacious' and 1 RCT for a designation as 'possibly efficacious'. Applying these criteria modified by Chambless and Hollon, this article presents an update on the evidence for psychodynamic therapy (PDT) in specific mental disorders. METHODS: A systematic search was performed using the criteria by Chambless and Hollon for study selection, as follows: (1) RCT of PDT in adults, (2) use of reliable and valid measures for diagnosis and outcome, (3) use of treatment manuals or manual-like guidelines, (4) adult population treated for specific problems and (5) PDT superior to no treatment, placebo or alternative treatment or equivalent to an established treatment. RESULTS: A total of 39 RCTs were included. Following Chambless and Hollon, PDT can presently be designated as efficacious in major depressive disorder (MDD), social anxiety disorder, borderline and heterogeneous personality disorders, somatoform pain disorder, and anorexia nervosa. For MDD, this also applies to the combination with pharmacotherapy. PDT can be considered as possibly efficacious in dysthymia, complicated grief, panic disorder, generalized anxiety disorder, and substance abuse/dependence. Evidence is lacking for obsessive-compulsive, posttraumatic stress, bipolar and schizophrenia spectrum disorder(s). CONCLUSIONS: Evidence has emerged that PDT is efficacious or possibly efficacious in a wide range of common mental disorders. Further research is required for those disorders for which sufficient evidence does not yet exist.


Assuntos
Transtorno Depressivo Maior/terapia , Transtornos Mentais/terapia , Psicoterapia Psicodinâmica , Adulto , Terapia Cognitivo-Comportamental , Transtorno Depressivo Maior/psicologia , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Indian J Hematol Blood Transfus ; 31(1): 14-20, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25548439

RESUMO

Prognosis of peripheral and other advanced T cell lymphomas is poor. 20 patients with a median age of 46.4 (range 20.5-64.1) years were treated with autoSCT (n = 6) or alloSCT (n = 14) from 1996 to 2013. All patients were at high risk either due to the IPI-score or to the fact that SCT was part of a salvage therapy. Conditioning prior to alloSCT was myeloablative in seven cases (50 %). The patients were pretreated with 8.5 (median, range 2-38) cycles of chemotherapy. Ten patients are alive in CR after a median follow-up of 1.3 years (range 0.1-13.3). OS was 53 % after one and 40 % after 10 years. Best survival was reached after related alloSCT (80 % at 10 years) compared to other modalities. GvHD did not influence survival. AlloSCT from related donors can cure patients from T-cell lymphomas. Unrelated alloSCT or high-dose therapy and autoSCT are an option for patients without a familiar donor.

9.
Br J Clin Psychol ; 54(1): 109-25, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25145630

RESUMO

OBJECTIVES: Whether personality characteristics have an impact on treatment outcome is an important question in psychotherapy research. One of the most common approaches for the description of personality is the five-factor model of personality. Only few studies investigated whether patient personality as measured with the NEO-Five-Factor Inventory (NEO-FFI, Costa & McCrae [1992b]. Revised NEO-PI-R and NEO-FFI. Professional manual. Odessa, FL: Psychological Assessment Recources) predicts outcome. Results were inconsistent. Studies reporting personality to be predictive of outcome did not control for baseline symptoms, while studies controlling initial symptoms could not support these findings. We hypothesized that after taking into account baseline symptoms, the NEO-FFI would not predict outcome and tested this in a large sample of inpatients at a psychosomatic clinic. DESIGN: Naturalistic, non-controlled study using patients' data for multiple regression analysis to identify predictors of outcome. METHODS: Data of 254 inpatients suffering primarily from depressive, anxiety, stress, and somatoform disorders were analysed. Personality was assessed at the beginning of therapy. For psychotherapy outcome, changes in anxiety and depression (Hospital Anxiety and Depression Scale; HADS), overall psychopathology (Symptom Checklist-90-R Global Severity Index [GSI]), and interpersonal problems (Inventory of Interpersonal Problems; IIP) were measured. RESULTS: The treatment resulted in significant decreases on all outcome measures corresponding to moderate to large effect sizes (HADS: d = 1.03; GSI: d = 0.90; IIP: d = 0.38). Consistent with our hypothesis, none of the personality domains predicted outcome when baseline symptoms were controlled for. CONCLUSIONS: Personality assessment at baseline does not seem to have an added value in the prediction of inpatient psychotherapy outcome beyond initial symptoms. PRACTITIONER POINTS: Clinical implications Personality dimensions overlap with symptomatic distress. Rather than serve as predictors of outcome, the domains tapped by the NEO-FFI reflect current psychological symptomatology in inpatients with depressive, anxiety, stress or somatoform disorders. From a clinician's point of view monitoring individual progress by using actuarial measures is more valuable than trying to predict who will benefit from treatment using personality assessments. Limitations of the study Diagnostic assessment was solely based on clinical evaluation rather than structured interviews. Twenty-five per cent of the original sample had to be excluded due to missing data. There was a focus on only one set of client characteristics (i.e., five-factor model personality traits). Assessment of personality domains in the acute phase of a mental disorder may be problematic and could have influenced findings.


Assuntos
Transtornos da Personalidade/diagnóstico , Personalidade , Transtornos Psicofisiológicos/terapia , Psicoterapia/métodos , Adulto , Feminino , Humanos , Pacientes Internados , Masculino , Transtornos Mentais , Pessoa de Meia-Idade , Determinação da Personalidade , Transtornos da Personalidade/psicologia , Inventário de Personalidade/estatística & dados numéricos , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Transtornos Psicofisiológicos/psicologia , Análise de Regressão , Resultado do Tratamento
10.
Chem Soc Rev ; 43(14): 5106-39, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-24916774

RESUMO

Recent theoretical studies are reviewed which show that the naked group 14 atoms E = C-Pb in the singlet (1)D state behave as bidentate Lewis acids that strongly bind two σ donor ligands L in the donor-acceptor complexes L→E←L. Tetrylones EL2 are divalent E(0) compounds which possess two lone pairs at E. The unique electronic structure of tetrylones (carbones, silylones, germylones, stannylones, plumbylones) clearly distinguishes them from tetrylenes ER2 (carbenes, silylenes, germylenes, stannylenes, plumbylenes) which have electron-sharing bonds R-E-R and only one lone pair at atom E. The different electronic structures of tetrylones and tetrylenes are revealed by charge- and energy decomposition analyses and they become obvious experimentally by a distinctively different chemical reactivity. The unusual structures and chemical behaviour of tetrylones EL2 can be understood in terms of the donor-acceptor interactions L→E←L. Tetrylones are potential donor ligands in main group compounds and transition metal complexes which are experimentally not yet known. The review also introduces theoretical studies of transition metal complexes [TM]-E which carry naked tetrele atoms E = C-Sn as ligands. The bonding analyses suggest that the group-14 atoms bind in the (3)P reference state to the transition metal in a combination of σ and π∥ electron-sharing bonds TM-E and π⊥ backdonation TM→E. The unique bonding situation of the tetrele complexes [TM]-E makes them suitable ligands in adducts with Lewis acids. Theoretical studies of [TM]-E→W(CO)5 predict that such species may becomes synthesized.

11.
Langmuir ; 30(24): 7070-6, 2014 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-24866927

RESUMO

We report a reversible phase separation phenomenon in nonpolar colloidal suspensions of rod-shaped dichroic pigment particles in an electric field. The voltage-frequency phase diagram features a variety of phases with different morphologies. Single static particle-rich islands, chains of islands, and dynamic patterns were found in this system. We demonstrate that those patterns exhibit complex relaxation dynamics toward the homogeneous field-free state once the external field is removed.

12.
Philos Trans A Math Phys Eng Sci ; 371(1988): 20120253, 2013 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-23459957

RESUMO

In recent years, several papers reported an enhanced dielectric anisotropy when ferroelectric particles were suspended in a liquid crystal. These results seem to be sensitive to the liquid crystal used and the preparation method of the ferroelectric particles. In this paper, we compare different preparation methods of suspended barium titanate in two different liquid crystal hosts. As a control experiment, we followed similar preparation steps with non-ferroelectric silica particles. In all cases, we found a broadening of the optical Frederiks transition but no change in the dielectric anisotropy. Raman spectroscopy has been used to investigate the loss of tetragonal structure in the barium titanate as a function of milling time and particle size. As reported in the earlier literature, barium titanate does not exhibit a well-defined tetragonal crystal structure below a certain particle size and loses its ferroelectric features. This provides a simple rationalization for the absence of any dielectric enhancement.

13.
Philos Trans A Math Phys Eng Sci ; 371(1988): 20120257, 2013 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-23459960

RESUMO

The response of anisotropic pigment particle suspensions to externally applied electric fields has been explored for possible application in reflective display technologies. Three different types of pigment particle were suspended in dodecane, using a polymeric stabilizer, and showed Schlieren textures between crossed polarizers at high concentrations (greater than 25-30 wt%), indicating the formation of colloidal nematic phases. Orientational order parameters were determined by X-ray scattering, and the influence of polydispersity on the values is discussed. X-ray scattering measurements also demonstrated a change in the structure factor consistent with the onset of a colloidal nematic phase. In addition, the pigment particles were dispersed into various liquid crystal hosts at low concentrations (less than 5 wt%) with and without the presence of mesogenic mimic stabilizers. However, the influence of these stabilizers on orientational ordering could not be confirmed. The electro-induced ordering determined via scattering was related to the electro-optical response of each suspension using a simple model. The particles in nematic hosts not only showed a high degree of orientational ordering at lower electric field strengths, but also showed a reduction in stability. Although these systems have shown strong orientational ordering, the optical response has been limited by the intrinsic shape of the pigment particles and the distribution of the transition dipoles moments within them. Nevertheless, the feasibility of developing materials for display applications has been demonstrated.

14.
Philos Trans A Math Phys Eng Sci ; 371(1988): 20120510, 2013 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-23459969
15.
Pediatr Infect Dis J ; 31(11): 1148-52, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22863912

RESUMO

INTRODUCTION: In contrast to varicella zoster virus (VZV) primary infection, VZV vaccination does not seem to provide lifelong immunity against varicella. Because more people get vaccinated every year, the development of sensitive serological test systems for the detection of protective anti-VZV IgG will become important in the future. METHODS: We have previously developed a novel VZV line assay based on 5 different recombinant VZV antigens. In this study, we compared this novel assay with a commercially available glycoprotein enzyme immunoassay (RIDASCREEN VZV IgG) in detecting anti-VZV IgG of children with previous varicella infection and VZV vaccination. RESULTS: One hundred twenty-five children were included in this study, 72 with a history of varicella infection and 53 with VZV vaccination. Both assays detected anti-VZV IgG antibodies in both study groups with similar sensitivities. The VZV line assay revealed striking differences in the anti-VZV IgG composition against the VZV open reading frames, 4, 14 and 49, between both study groups, indicating that wild-type varicella infection causes a more diverse immune response against VZV than does vaccination. The exploitation of these results enabled the discrimination of both study groups with a sensitivity of 0.93 and a specificity of 0.83, indicating that the serologic differentiation of children with previous varicella infection and VZV vaccination might be possible. CONCLUSION: The VZV line assay enables the detection of anti-VZV IgG with sensitivities comparable to glycoprotein enzyme immunoassays and might be suitable for the serologic discrimination between children with a history of varicella infection and VZV vaccination.


Assuntos
Anticorpos Antivirais/sangue , Vacina contra Varicela/imunologia , Varicela/imunologia , Herpesvirus Humano 3/classificação , Imunoglobulina G/sangue , Varicela/sangue , Vacina contra Varicela/sangue , Criança , Humanos , Testes Sorológicos
16.
Adv Mater ; 24(32): 4424-9, 2012 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-22761047

RESUMO

Self-assembled disc-shaped clusters of hexagonally packed, thiol-functionalized gold nanorods are prepared and dispersed in thermotropic nematic liquid crystals. The resultant hybrid complex fluids exhibit colloidal anisotropy with very high orientational order and are characterized by SAXS as shown in the figure. Precise, reconfigurable control of the cluster orientation at very low electric field strengths (0.18 V µm(-1) ) is achieved.


Assuntos
Ouro/química , Nanotubos/química , Coloides/química , Cristais Líquidos/química , Espalhamento a Baixo Ângulo , Difração de Raios X
17.
Chemistry ; 18(18): 5676-92, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22434609

RESUMO

Quantum chemical calculations using DFT (BP86, M05-2X) and ab initio methods (CCSD(T), SCS-MP2) have been carried out on the borylene complexes (BH)L(2) and nitrogen cation complexes (N(+))L(2) with the ligands L=CO, N(2), PPh(3), NHC(Me), CAAC, and CAAC(model). The results are compared with those obtained for the isoelectronic carbones CL(2). The geometries and bond dissociation energies of the ligands, the proton affinities, and adducts with the Lewis acids BH(3) and AuCl were calculated. The nature of the bonding has been analyzed with charge and energy partitioning methods. The calculated borylene complexes (BH)L(2) have trigonal planar coordinated boron atoms which possess rather short B-L bonds. The calculated bond dissociation energies (BDEs) of the ligands for complexes where L is a carbene (NHC or CAAC) are very large (D(e) =141.6-177.3 kcal mol(-1)) which suggest that such species might become isolated in a condensed phase. The borylene complexes (BH)(PPh(3))(2) and (BH)(CO)(2) have intermediate bond strengths (D(e) =90.1 and 92.6 kcal mol(-1)). Substituted homologues with bulky groups at boron which protect the boron atom from electrophilic attack might also be stable enough to become isolated. The BDE of (BH)(N(2))(2) is much smaller (D(e) =31.9 kcal mol(-1)), but could become observable in a low-temperature matrix. The proton affinities of the borylene complexes are very large, particularly for the bulky adducts with L=PPh(3), NHC(Me), CAAC(model) and CAAC and thus, they are superbases. All (BH)L(2) molecules bind strongly AuCl either η(1) (L=N(2), PPh(3), NHC(Me), CAAC) or η(2) (L=CO, CAAC(model)). The BDEs of H(3)B-(BH)L(2) adducts which possess a hitherto unknown boron→boron donor-acceptor bond are smaller than for the AuCl complexes. The strongest bonded BH(3) adduct that might be isolable is (BH)(PPh(3))(2)-BH(3) (D(e) =36.2 kcal mol(-1)). The analysis of the bonding situation reveals that (BH)-L(2) bonding comes mainly from the orbital interactions which has three major contributions, that is, the donation from the symmetric (σ) and antisymmetric (π(||)) combination of the ligand lone-pair orbitals into the vacant MOs of BH L→(BH)←L and the L←(BH)→L π backdonation from the boron lone-pair orbital. The nitrogen cation complexes (N(+))L(2) have strongly bent L-N-L geometries, in which the calculated bending angle varies between 113.9° (L=N(2)) and 146.9° (L=CAAC). The BDEs for (N(+))L(2) are much larger than those of the borylene complexes. The carbene ligands NHC and CAAC but also the phosphane ligands PPh(3) bind very strongly between D(e) =358.4 kcal mol(-1) (L=PPh(3)) and D(e) =412.5 kcal mol(-1) (L=CAAC(model)). The proton affinities (PA) of (N(+))L(2) are much smaller and they bind AuCl and BH(3) less strongly compared with (BH)L(2). However, the PAs (N(+))L(2) for complexes with bulky ligands L are still between 139.9 kcal mol(-1) (L=CAAC(model)) and 168.5 kcal mol(-1) (L=CAAC). The analysis of the (N(+))-L(2) bonding situation reveals that the binding interactions come mainly from the L→(N(+))←L donation while L←(N(+) )→L π backdonation is rather weak.

18.
J Am Chem Soc ; 133(44): 17552-5, 2011 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-21999232

RESUMO

A stable silicon analogue of an acid anhydride {PhC(Bu(t)N)(2)}Si{═O·B(C(6)F(5))(3)}O-Si(H){═O·B(C(6)F(5))(3)}{(NBu(t))(HNBu(t))CPh} (4) with a O═Si-O-Si═O core has been prepared by treating monochlorosilylene PhC(Bu(t)N)(2)SiCl (1) with H(2)O·B(C(6)F(5))(3) in the presence of NHC (NHC = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene). Compound 4 has been characterized by elemental analysis and multinuclear NMR spectroscopic investigations. The molecular structure of 4 has been established by single-crystal X-ray diffraction studies, and DFT calculations support the experimental results.

19.
Appl Spectrosc ; 65(10): 1181-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21986078

RESUMO

Optical characterization of three red pigments, two organic and one inorganic, was studied in order to provide important and reliable parameters for research and applications. The pigments were C.I. Pigment Red 176, C.I. Pigment Red 57:1, and C.I. Pigment Red 101. All three pigments were used in their transparent form, that is, their radius of gyration was smaller than 250 nm. The particles were suspended in an apolar solvent and absorption, reflection, and scattering of the suspensions were measured by means of a single spectrophotometer and the effective complex refractive index was determined.

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