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The emission spectrum of HfCl has been investigated in the 3000–18 500 cm−1region at high resolution using a Fourier transform spectrometer. The bands were excited in a microwave discharge through a flowing mixture of HfCl4and helium. Two bands near 17 140 and 17 490 cm−1were also measured in absorption using laser excitation spectroscopy. In this instance the molecules were created by laser ablation in a molecular beam apparatus. The observed bands have been classified into two electronic transitions, [7.6]4Δ3/2–X2Δ3/2and [17.1]2Δ3/2–X2Δ3/2involving a common lower state. A rotational analysis of the 0–0 and 1–1 bands of [7.6]4Δ3/2–X2Δ3/2and 0–0, 1–1, and 1–0 bands of the [17.1]2Δ3/2–X2Δ3/2transitions has been carried out and the equilibrium spectroscopic constants have been determined. The ground state principal molecular constants are Be= 0.1097404(54) cm−1, αe= 0.0004101(54) cm−1, and re= 2.290532(57) Å. Ab initiocalculations have been performed on HfCl and spectroscopic properties of the low-lying electronic states have been predicted. The ground state is predicted to be a regular 2Δ state arising from the valence electron configuration, 1ς22ς23ς21π41δ1. On the basis of our ab initiocalculations, we assign the observed transitions as [7.6]4Δ3/2–X2Δ3/2and [17.1]2Δ3/2–X2Δ3/2.

The high-resolution spectrum of NbN has been investigated in emission in the 3000–15000 cm−1region using a Fourier transform spectrometer. The bands were excited in a microwave discharge through a mixture of NbCl5vapor, ∼5 mTorr of N2, and 3 Torr of He. Numerous bands observed in the near-infrared region have been classified into the following transitions: f1Φ–c1Γ, e1Π–a1Δ, C3Π0+–A3Σ−1, C3Π0−–A3Σ−1, C3Π1–a1Δ, C3Π1–A3Σ−0, d1Σ+–A3Σ−0, and d1Σ+–b1Σ+. These observations are consistent with the energy level diagram provided by laser excitation and emission spectroscopy [Y. Azuma, G. Huang, M. P. J. Lyne, A. J. Merer, and V. I. Srdanov, J. Chem. Phys.100, 4138–4155 (1993)]. The missing d1Σ+state has been observed for the first time and its spectroscopic parameters are consistent with the theoretical predictions of S. R. Langhoff and W. Bauschlicher, Jr. [J. Mol. Spectrosc.143, 169–179 (1990)]. Rotational analysis of a number of bands has been obtained and improved spectroscopic parameters have been extracted for the low-lying electronic states. The observation of several vibrational bands with v= 1 has enabled us to determine the vibrational intervals and equilibrium bond lengths for the A3Σ−0, a1Δ, b1Σ+, d1Σ+, and C3Π1states.

The 000bands of the Ã2B2–X̃2A1and B̃2B1–X̃2A1systems of SrNH2were observed at Doppler-limited resolution using a Broida oven source and laser-induced fluorescence detection. A full rotational analysis of both transitions was performed including Kalevels up to 5 and Jlevels up to 55. The B̃2B1state was found to be extensively perturbed and only some of the subbands could be analyzed. The Ã2B2and B̃2B1states undergo a strong Coriolis-type interaction which results in extremely large spin–rotation splittings in both states, effectively splitting all levels with Ka′≠ 0 into two well-separated spin components.

Autosomal dominant polycystic kidney disease (ADPKD) is a genetically heterogeneous disorder that can be caused by mutations in at least three different genes. Several mutations have been identified in PKD1 and PKD2 genes. Most of the mutations found in PKD2 gene are predicted to cause premature termination of the protein.

The laser-induced fluorescence (LIF) spectrum of the B3Π0+u–X1Σ+gsystem of Br2was recorded by Fourier transform spectroscopy (FTS). The LIF spectra were obtained by using continuous-wave dye laser excitation in the spectral region 16 800–18 000 cm−1. About 1800 rotationally resolved lines were recorded in 96 fluorescence progressions, originating from the 10 ≤ v′ ≤ 22 vibrational levels of the B3Π0+ustate and involving the 2 ≤ v" ≤ 29 levels of the X1Σ+gground state of the three isotopomers of bromine, 79Br2, 81Br2, and 79,81Br2. These data, together with 79Br2data from a previous FTS absorption study [S. Gerstenkorn, P. Luc, A. Raynal, and J. Sinzelle, J. Phys. (France)48, 1685–1696 (1987)], were analyzed to yield improved Dunham constants for the ground state. A Rydberg–Klein–Rees (RKR) potential energy curve was computed for the X1Σ+gstate (v" = 0–29). The equilibrium bond length was found to be Re(X1Σ+g) = 2.2810213(20) Å.

The infrared spectrum of a sunspot is analyzed in the L-band region 3.1-4.0 mm (2497-3195 cm-1) and 2.02-2.35 mm (4251-4962 cm-1) in the K band. A new laboratory emission spectrum covering 2500- 6000 cm-1 is analyzed to help make the assignments. Quantum number assignments are made using linelists computed using variational calculations, assisted by tabulations of experimental energy levels. There are 1207 new H216O lines assigned in the L band and 508 new lines in the K band. Vibrational band origins of 11242.8 +- 0.1 cm-1 and 12586 +- 1 cm-1 are obtained for the (051) and (061) states.

Using multidecadal time series of ground‐based and satellite Fourier transform infrared measurements of inorganic fluorine (i.e., total fluorine resident in stratospheric fluorine reservoirs), we investigate stratospheric circulation changes over the past 20 years. The representation of these changes in five modern reanalyses is further analyzed through chemical‐transport model (CTM) simulations. From the observations but also from all reanalyses, we show that the inorganic fluorine is accumulating less rapidly in the Southern Hemisphere than in the Northern Hemisphere during the 21st century. Comparisons with a study evaluating the age‐of‐air of these reanalyses using the same CTM allow us to link this hemispheric asymmetry to changes in the Brewer‐Dobson circulation (BDC), with the age‐of‐air of the Southern Hemisphere getting younger relative to that of the Northern Hemisphere. Large differences in simulated total columns and absolute trend values are, nevertheless, depicted between our simulations driven by the five reanalyses. Superimposed on this multidecadal change, we, furthermore, confirm a 5–7‐year variability of the BDC that was first described in a recent study analyzing long‐term time series of hydrogen chloride (HCl) and nitric acid (HNO3). It is important to stress that our results, based on observations and meteorological reanalyses, are in contrast with the projections of chemistry‐climate models in response to the coupled increase of greenhouse gases and decrease of ozone‐depleting substances, calling for further investigations and the continuation of long‐term observations. The overturning circulation of the stratosphere is projected to change in response to increases in greenhouse gases and decreases in ozone‐depleting substances, with the Southern Hemisphere branch expected to get weaker relative to the Northern Hemisphere. Here, we use 30‐year time series of observations and simulations of a long‐lived tracer to investigate stratospheric circulation changes. The observations analyzed are from ground‐based and satellite instruments. We compare them with simulations that use a chemical‐transport model driven by winds from meteorological reanalyses of 1990–2019. A reanalysis assimilates meteorological measurements into a forecast model to simulate the best possible representation of the atmospheric state. All five simulations, which use different reanalyses, agree with the observational analysis showing that the analyzed tracer is accumulating less rapidly in the Southern Hemisphere than in the Northern Hemisphere through 2019. This hemispheric asymmetry is attributed to changes in the stratospheric transport circulation, with the Southern Hemisphere branch getting stronger relative to the Northern Hemisphere. Our results support the conclusions of a recent observational study but do not support circulation changes projected by chemistry‐climate models. This study highlights the crucial importance of long‐term observation time series. Fluorine in the stratosphere is accumulating less rapidly in the Southern Hemisphere than in the Northern HemisphereThe observed fluorine trend asymmetry, attributed to transport circulation changes, opposes trends predicted by chemistry‐climate modelsObservations and five modern reanalyses are qualitatively in agreement with these changes, calling for maintaining long‐term observations Fluorine in the stratosphere is accumulating less rapidly in the Southern Hemisphere than in the Northern Hemisphere The observed fluorine trend asymmetry, attributed to transport circulation changes, opposes trends predicted by chemistry‐climate models Observations and five modern reanalyses are qualitatively in agreement with these changes, calling for maintaining long‐term observations

The A2Π–X2Σ+Δv= 0 sequence of BeD was observed in the 19 500–20 800 cm−1spectral region using a Fourier transform spectrometer. The emission spectrum was excited in a Be hollow cathode discharge lamp with a He/D2gas mixture. The observed lines were assigned to the 0–0 to 6–6 bands. The Δv= −1 sequence was too weak to be seen in our Fourier transform spectra. We therefore used a previously recorded but unpublished arc emission spectrum to identify the 0–1 to 5–6 Δv= −1 bands. Consequently, all of the diagonal bands could be linked together and the vibrational intervals determined. The Δv= 0 and Δv= −1 data were fitted together in a global fit and effective constants derived. Using the information available from the study of the C2Σ+–X2Σ+system [R. Colin, C. Drèze, and M. Steinhauer,Can. J. Phys.61, 641 (1983)], thev= 8–12 vibrational levels of the ground state were added in a Dunham fit. A set of Dunham Y constants was determined for the X2Σ+state along with traditional equilibrium parameters for the A2Π excited state. The equilibrium bond lengths were found to be 1.341742(5) Å for the ground state and 1.33309(4) Å for the excited state. A reanalysis of the previously published A2Π–X2Σ+0–0 to 3–3 Δv= 0 bands of BeT [D. De Greef and R. Colin,J. Mol. Spectrosc.53, 455–465 (1974)] was also performed.

High-resolution emission spectra of TiCl have been recorded in the 10000–18000 cm−1region using a Fourier transform spectrometer. The molecules were excited in a microwave discharge through a flowing mixture of TiCl4and helium. TiCl bands observed in the 11000–13500 cm−1region have been assigned to a new [12.8]2Φ–a2Φ electronic transition with the 0–0 bands of2Φ5/2–2Φ5/2and2Φ7/2–2Φ7/2subbands at 12733.7 and 12791.5 cm−1, respectively. A rotational analysis of several bands has been obtained, and spectroscopic constants have been extracted. This assignment is supported by the available theoretical calculations and is also consistent with the near infrared measurements of a doublet–doublet transition of ZrCl [J. G. Phillips, S. P. Davis, and D. C. Galehouse,Astrophys. J. Suppl. Ser.43, 417–434) (1980)].

Extensive new high-temperature, high-resolution FTIR emission spectroscopy measurements for the five common isotopomers of GeO are combined with previous diode laser and microwave measurements in combined isotopomer analyses. New Dunham expansion parameters and an accurate analytical potential energy function are determined for the groundX1Σ+state.

We have identified lines from the 0-3, 0-4, 0-5, 0-6, 0-7, 1-3, 1-4, 1-7, and 1-8 bands of the 24MgH B' 2S+-X 2S+ transition in sunspot umbral spectra. Lines of the 0-7 and 1-8 bands in the uncluttered 7500 A region are the most obvious, but B' 2S+-X 2S+ lines have been tracked as far to the blue as 5300 A. In combination with weak lines of the 0-7 bands of the 25MgH and 26MgH isotopes, the solar isotope ratio 24Mg:25Mg:26Mg has been measured as 76:12:12, in agreement with the much better determined terrestrial ratio 79:10:11. The intensity distribution of bands with v'' from 4 to 8 has been measured and found to show no anomalies; the excitation temperature of 3100 K agrees well with a value of 3200 K determined from SiO in a sunspot spectrum. The lines of the MgH B' 2S+-X 2S+ transition are much more cleanly separated and much less blended than lines from the stronger A 2P-X 2S+ transition. The B' 2S+-X 2S+ lines should prove useful in isotopic abundance analyses for stars where the A 2P-X 2S+ transition is too strong to yield useful results.

Emission spectra have been recorded for hot water at temperatures up to 1550°C. Separate spectra have been recorded in the 800–1900 and 1800–2500 cm−1range. Assignments are made using a linelist generated from high accuracy, variational nuclear motion calculations, and energy differences. The spectra contain many hot bending transitions of the form (0n0)–(0n–10), where states up ton= 6 have been assigned. Detailed analysis shows that the spectra contain lines from 34 separate vibrational bands including other hot bending transitions and the difference bands (030)–(100), (110)–(020), (011)–(020), (100)–(010), (040)–(110), (040)–(011), (120)–(030), (012)–(030), (011)–(100), (110)–(001), and (101)–(110), all of which have not been observed previously. From a total of 8959 lines recorded, 6810 have been assigned; 4556 of these lines are new. These spectra represent the first detection of the (060) vibrational band, for which a band origin of 8870.54 ± 0.05 cm−1is determined. The (050) band origin is confirmed as 7542.40 ± 0.03 cm−1. The assignments extend the range ofJandKavalues observed for the bending states, particularly for (050) and (060), where 63 and 27 different rotational levels, respectively, have now been observed; 53 frequencies given in HITRAN are corrected.

The emission spectrum of ZrCl has been observed in the 1800–12 000 cm−1region using a Fourier transform spectrometer. The molecules were excited in a microwave discharge of a mixture of helium and a trace of ZrCl4vapor. In addition to the C4Δ–X4Φ transition reported previously, numerous new bands observed in the near infrared have been classified into two electronic transitions, [7.3]2Δ–a2Φ and [9.4]2Φ–a2Φ. Five new bands observed in the 6700–7400 cm−1region have been assigned as 2Δ3/2–2Φ5/2and 2Δ5/2–2Φ7/2subbands of a new electronic transition, [7.3]2Δ–a2Φ. The two subbands of the [9.4]2Φ–a2Φ transition were previously observed by G. Phillips, S. P. Davis, and D. C. Galehouse [Astrophys. J. Suppl.43, 417–434 (1980)], who tentatively labeled them as 2Π1/2–2Π1/2and 2Π3/2–2Π3/2subbands. A number of new bands involving higher vibrational levels have been identified for these two subbands. A rotational analysis of a number of bands of both transitions has been obtained and spectroscopic constants have been determined. Global perturbations have been observed in both spin components of the a2Φ state. The assignment of the observed electronic states has been discussed in light of recent theoretical calculations.

The emission spectrum of IrN has been investigated in the 10 000–20 000 cm−1region at 0.02 cm−1resolution using a Fourier transform spectrometer. The bands were excited in an Ir hollow cathode lamp operated with a mixture of 2 Torr of Ne and a trace of N2. Numerous bands have been classified into two transitions labeled asA1Π–X1Σ+andA′1Π–X1Σ+by analogy with the isoelectronic PtC molecule. Ten bands involving vibrational levels up toKv= 4 in the ground and excited states have been identified in theA1Π–X1Σ+transition. This electronic transition has been previously observed by [A. J. Marr, M. E. Flores, and T. C. Steimle, J. Chem. Phys. 104, 8183–8196 (1996)]. To lower wavenumbers, five additional bands withRheads near 12 021, 12 816, 13 135, 14 136, and 15 125 cm−1have been assigned as the 0–1, 3–3, 0–0, 1–0, and 2–0 bands, respectively, of the newA′1Π–X1Σ+transition. A rotational analysis of these bands has been carried out and equilibrium constants for the ground and excited states have been extracted. TheKv= 2 and 3 vibrational levels of theA′1Π state interact with theKv= 0 and 1 levels of theA1Π state and cause global perturbations in the bands. The ground state equilibrium constants for193IrN are: ωe= 1126.176360(61) cm−1, ωexe= 6.289697(32) cm−1,Be= 0.5001033(20) cm−1, αe= 0.0032006(20) cm−1, andre= 1.6068276(32) Å.

The emission spectrum of IrN was recorded in the near infrared using a Fourier transform spectrometer. The IrN molecules were excited in an Ir hollow cathode lamp operated with a mixture of Ne and a trace of N2. Numerous IrN bands observed in the 7500–9200 cm−1region were assigned to a new a3Π–X1Σ+electronic transition with the 0–0 bands of the a3Π0–X1Σ+and a3Π1–X1Σ+subbands near 9175 and 8841 cm−1, respectively. A rotational analysis of several bands of the 0–0 and 0–1 sequences was obtained and molecular constants were extracted. The effective Hund's case (a) constants for the new a3Π state are: T00= 8840.31747(88) cm−1, A0= −340.53329(93) cm−1, ΔG(1/2) = 984.3629(23) cm−1, Be= 0.4699116(27) cm−1, αe= 0.0030058(50) cm−1, and re= 1.6576432(47) Å. The spectroscopic properties of the ground state and several low-lying electronic states of IrN were also predicted by ab initiocalculations. These calculations are consistent with our assignment of the a3Π–X1Σ+transition and also support our previous assignments of the A′ 1Π and A1Π electronic states [R. S. Ram and P. F. Bernath, J. Mol. Spectrosc. 193, 363 (1999)]. The excited a3Π state of IrN has an 1ς22ς21π43ς11δ42π1electron configuration and the configurations of the other low-lying electronic states are also discussed.

The high resolution infrared spectrum of LiF has been measured in emission with the McMath Fourier transform interferometer at Kitt Peak. A total of 800 lines with ν = 1 → 0 to ν = 8 → 7 of the main isotopomer, 7LiF, and 250 lines with ν = 1 → 0 to ν = 3 → 2 of the minor isotopomer, 6LiF, were observed. These ro-vibrational transitions and the pure rotational transitions from the literature were fit to a set of Dunham coefficients Yijand a set of mass-reduced Dunham coefficients Uij. The same spectrum shows 13 pure rotational emission transitions of HF in the vibrational ground state with J = 13 → 12 to J = 25 → 24. These transitions were used to determine an improved set of rotational constants for HF. Keywords: infrared spectra, LiF, HF.

In this study, L-Asparaginase has been bound to collagen heterografts derived from carotid bovine arteries. The immobilization procedure utilizes both non-covalent and covalent interactions to fix the enzyme. Binding of the enzyme to the graft material was shown to be pH dependent, with optimum binding occurring at pH 6.0 and pH 8.5. Amidohydrolysis by the bound enzyme exhibited zero-order kinetic behavior at substrate saturating conditions. Total apparent asparaginase activity expressed by the grafts as a function of the number of repeated in vitro assay trials demonstrated that over a span of 3 months of intermittent storage and use, the enzyme-grafts retained as much as 62% of their initial activities. Implantation of 4 asparaginase-collagen grafts in various locations of the thoracic and abdominal aorta resulting in prolonged reductions of plasma asparagine levels in 3 of the 4 implants. Presence of plasma asparaginase was checked in one of the four implants and determined to be less than 2 × 10-4 I.U./ml. Removal of grafts from 3 of the 4 animal subjects showed reductions in the apparent asparaginase activity expressed by the grafts of 7 to 70 percent after in vivo contact times which varied from 6 to 15 days.

The high-resolution infrared emission spectrum of boron monofluoride was recorded with a Fourier transform spectrometer. There are 359 transitions of 11BF with ν = 1 → 0 to ν = 5 → 4, and 94 transitions of 10BF with ν = 1 → 0 to ν = 3 → 2 assigned. Improved Dunham Yijcoefficients for the ground X1Σ+electronic state were determined from the infrared data combined with existing microwave data. The mass-reduced Dunham Uijcoefficients were also obtained along with Born-Oppenheimer breakdown constants. An effective Born-Oppenheimer potential was determined by fitting the available data to the eigenvalues of the radial Schrödinger equation containing a parameterized potential function. Finally, the relative transition dipole moments of the major isotopomer 11BF were also measured. For AlF, our previous measurements were extended to higher ν and J, in order to obtain improved Dunham coefficients and an improved internuclear potential.

The electronic emission spectrum of HfN has been observed in the near infrared using a Fourier transform spectrometer. HfN molecules were excited in a hafnium hollow cathode lamp operated with neon gas and a trace of nitrogen. The bands located near 5746, 5802, 6668, and 6715 cm−1have been assigned as the 0–1, 1–2, 0–0, and 1–1 bands of the [6.7]2Σ+–X2Σ+transition. The rotational analysis of these bands has been performed and the equilibrium molecular constants for the lower electronic state of180HfN are ωe= 932.7164(15) cm−1, ωexe= 4.41299(65) cm−1,Be= 0.436217(18) cm−1, αe= 0.002659(11) cm−1, andre= 1.724678(36) Å. We believe that the lower state of this transition is the ground electronic state but more experimental and theoretical work is necessary to prove this. Our work represents the first experimental observation of an electronic transition of HfN.

The infrared vibration–rotation bands of ND in theX3Σ−state were recorded using a Fourier transform spectrometer. The bands were observed in a microwave discharge of a mixture of N2and D2in the presence of He. The rotational structure of six bands, 1–0, 2–1, 3–2, 4–3, 5–4, and 6–5, has been observed in the 1800–2600 cm−1region. The analysis of these bands provides an independent determination of the ground state vibrational con- stants in addition to an improved set of rotational constants. The principal molecular constants for the ground state are[formula]The molecular constants for PH have also been refined by combining the previous infrared [J. Mol. Spectrosc.122,275–281 (1987)] and the recent submillimeter-wave [Chem. Phys. Lett.211,443–448 (1993)] measurements.

The high-resolution infrared emission spectra of gas-phase barium monofluoride have been observed by Fourier transform spectrometry. Vibration-rotation bands were analyzed for the three most abundant isotopomers (138BaF, from 1-0 to 12-11; 137BaF, from 1-0 to 5-4; 136BaF, from 1-0 to 4-3) of the ground X2Σ+state. The Dunham coefficients, Ylm, have been derived for all three isotopomers by fitting about 1750 lines for 138BaF, about 270 lines for 137BaF, and about 70 lines for 136BaF to the traditional Dunham model. In addition, the mass-reduced Dunham constants, Ulm, have been calculated from a global least-squares fit.

The vibration-rotation emission spectrum of HBr was recorded with a Fourier transform spectrometer. Line positions for the 1-0 and 2-1 bands were measured for both H79Br and H81Br. A pure rotation emission spectrum of HBr was also obtained, and rotational lines for v = 0 were measured. The two sets of data, when combined with previously measured submillimeter-wave pure rotational transitions, yielded a set of improved rotational constants for H79Br and H81Br.Copyright 1994, 1999 Academic Press

1. Factors influencing the release of atrial natriuretic peptide (ANP) are not well understood. We chose a conscious euvolaemic canine model of cardiac tamponade to investigate the roles played by atrial blood pressure, transmural atrial pressure, atrial size, and arginine vasopressin (AVP) on ANP release since during cardiac tamponade the atrial transmural pressure and size decrease as atrial pressure increases. The haemodynamic response to acute cardiac tamponade in conscious dogs differs from that in anaesthetized or convalescent animals. 2. Eighteen mongrel dogs were prepared for the chronic measurement of: ascending aortic blood flow (electromagnetic flowmeter); intrapericardial, right atrial and aortic blood pressures, and the evaluation of right atrial size (two‐dimensional echocardiography). After the animals had recovered from surgery, data were collected during progressive cardiac tamponade induced by intrapericardial infusion of warmed saline (20 ml/min) to the point of haemodynamic decompensation. Decompensated cardiac tamponade (DCT) was defined as a decline in mean aortic blood pressure to 70% of the level present when the pericardial space was drained of fluid (baseline) and was produced in all animals within 25 min. Plasma ANP and AVP levels were measured at selected intervals. 3. Cardiac output decreased progressively as intrapericardial pressure, right atrial blood pressure and heart rate increased. Mean aortic blood pressure was well maintained until late in tamponade when it declined rapidly, while atrial transmural pressure and atrial size decreased continuously. These haemodynamic changes were associated with stable ANP plasma levels. There was no significant change in AVP plasma levels from the baseline level of 2.5 +/‐ 0.4 pg/ml until the point of DCT when they abruptly increased to 117 +/‐ 36.4 pg/ml. 4. The ability to increase ANP plasma levels was confirmed in a subgroup of animals by noting the response to AVP injection. Although the animals were able to increase plasma ANP levels in response to AVP injection (when intrapericardial pressure was normal) and the plasma AVP level was markedly increased late in tamponade, the time course of plasma AVP elevation could not explain why plasma ANP levels did not decrease as atrial transmural pressure and atrial size declined. 5. Thus, although atrial distention and not simply atrial blood pressure must play a dominant role in stimulating ANP release from the atria, decreased atrial size does not result in lowering of plasma ANP levels below baseline levels in this conscious euvolaemic canine model.

The emission spectra of ScH and ScD have been investigated in the near infrared and visible using a Fourier transform spectrometer. The molecules were excited in a scandium hollow cathode lamp operated with neon gas and a trace of hydrogen or deuterium. Apart from theX1Σ+,B1Π,C1Σ+, andG1Π states reported previously [R. S. Ram and P. F. Bernath,J. Chem. Phys.105,2668–2674 (1996)], four additional new singlet electronic statesA1Δ,D1Π,E1Δ, andF1Σ−have been identified below 21 000 cm−1. The rotational analysis of several vibrational bands of theD1Π–X1Σ+,D1Π–A1Δ,E1Δ–B1Π,E1Δ–A1Δ, andF1Σ−–B1Π transitions has been carried out and spectroscopic constants have been determined. TheE1Δ state of ScH was not located because of the very weak intensity of theE1Δ–B1Π andE1Δ–A1Δ transitions.

The high-resolution infrared spectrum of gas-phase SrF was obtained in emission with a Fourier transform spectrometer. Approximately 1400 rotational lines from the 1–0 to the 8–7 bands were measured in theX2Σ+ground state of the major isotopomer,88SrF. The Dunham coefficientsYl,mhave been derived from a combined fit of the infrared transitions with microwave transitions that have been previously reported in the literature.

An emission spectrum of the water molecule at a temperature of 1550°C has been recorded in the range from 373 to 933 cm−1. More than 4000 pure rotational lines were observed with the strongest belonging to the ground state (000) and the first excited bending vibrational level (010). Transitions involving rotational quantum numbersJandKasignificantly higher than previously recorded have been assigned.

Benzene is a major commodity chemical of great value to industry. It has long been recognized that overexposure to benzene could result in damage to the blood-forming organs of the body. More recently, it has become apparent that chronic high levels of exposure are associated with the development of leukemia. Animal experiments have also suggested that overexposure to benzene may result in certain reproductive risks.

The emission spectrum of TaO, excited in a tantalum hollow cathode lamp, has been observed at high resolution using a Fourier transform spectrometer. In addition to previously known transitions, a number of new bands have been identified and assigned as belonging to two new electronic transitions:H2Π1/2–X2Δ3/2andK2Φ5/2–X2Δ3/2. A rotational analysis ofthe 0–0 and 0–1 bands of theH2Π1/2–X2Δ3/2transition and of the 0–1, 1–2, 0–0, 1–0, and 2–1 bands of theK2Φ5/2–X2Δ3/2transition has been carried out, providing the following equilibrium constants for the groundX2Δ3/2state:ωe= 1028.9060(15) cm−1, ωexe= 3.58928(66) cm−1,Be= 0.40289737(139) cm−1, αe= 0.00185445(83) cm−1, andre= 1.6873430(29) Å. The principal molecular constants for theH2Π1/2state areT00= 20 634.32758 (40) cm−1,B0= 0.3766867(31) cm−1, andr0= 1.7450604(72) Å, while the equilibrium constants for theK2Φ5/2state areωe= 905.4549(15) cm−1, ωexe= 3.67601(64) cm−1,Be= 0.37965102(36) cm−1, αe= 0.00189370(21) cm−1, andre= 1.7382343(8) Å. Although theH2Π1/2andK2Φ5/2states have been observed previously in matrix isolation experiments, our work on these states is the first in the gas phase.

Evidence for intermolecular electrophilic halogenation of aromatic rings and olefinic double bonds by aliphatic chloramines at low pH, and for homolytic cyclization of unsaturated chloramines in neutral medium is presented. Independent proof of structure and stereochemistry of derivatives of 6-azabicyclo[3.2.1]octane and 2-azabicyclo[2.2.2]octane was provided. No evidence for involvement of nitrenium ions in the chloramine reactions was observed.

The electronic emission spectrum of WN has been observed in the 500–580-nm spectral region with a Fourier-transform spectrometer. The bands were excited in a tungsten hollow-cathode lamp in the presence of a trace of molecular nitrogen. The observed bands have been assigned to the A ^4-X ^4Σ^- transition. The ground state is a regular ^4Σ^- state belonging to Hund’s coupling case (a′). The principal ground-state constants obtained from the fit of the observed lines are B_0 = 0.4663779(62), D_0 = 3.5847(77) × 10^-7, γ_0 = 0.051862(21) cm^-1. The excited state, on the other hand, shows Hund’s case (c) tendencies with the spin components mixed because of interactions with other neighboring states. There have been no previous observations of the WN molecule to our knowledge.

Trust is a significant variable in children's personality, social, and intellectual development. Although trust research has primarily explored adult behavior, there is a growing body of research on children, with a particular emphasis on trust development within friendship relationships. This paper reviews the extant literature on children's trust. After summarizing historical theoretical perspectives, noting particularly Rotter's influence on the field, we offer a theoretical model of trust that synthesizes previous models. We describe various methods for assessing trust and argue for a multimethod approach consistent with our synthetic model. We review three research areas: antecedents to trust, the developmental course of trust in friendships, and correlates of trust. Implications for future research are indicated, and the absence of studies of practical applications is noted. Several programmatic applications for enhancing children's trust are presented.

The emission spectrum of ReN has been observed in the 400-476 nm spectral region using a Fourier transform spectrometer. The bands were excited in a rhenium hollow cathode lamp in the presence of a trace of N2. The observed bands, with the 0-0 band at 23 746.42 cm−1, have been assigned as the [23.8]1-X0+electronic transition. A rotational analysis of the 0-1, 0-0, and 1-0 bands for both 187ReN and 185ReN isotopomers has been performed. The principal ground state equilibrium molecular constants for 187ReN obtained from this analysis are B′′e= 0.482414(11) cm−1, r″e= 1.63780(2) Å, while the corresponding excited state values are B′e= 0.441093(13) cm−1, r′e= 1.71280(3) Å. The 0-0 band was also observed by pulsed dye laser excitation spectroscopy using a free jet expansion source. In this experiment, the ReN was made by laser vaporization of a rhenium rod followed by reaction with NH3. The excited [23.8]1 state has a fluorescence lifetime of 201 ± 1 nsec. There are no previously reported observations of the ReN molecule.

The emission spectrum of HfO has been investigated in the 400 nm to 5 μm spectral region with a Fourier transform spectrometer. The bands were excited in a hafnium hollow cathode lamp in the presence of neon and a trace of oxygen. In the 6900-8000 cm−1region, four new sequences of bands were observed with the 0-0 Qheads at 7060 cm−1, 7355.4 cm−1, 7376.8 cm−1, and 7929.5 cm−1. These bands have been identified as the 3Π0+-3Δ1, 3Π0−-3Δ1, 3Π1-3Δ2and 3Π2-3Δ3subbands of the b3Π-a3Δ transition. The rotational analysis of the 0-0 and 1-1 bands of each subband has been performed and the equilibrium rotational constants for each spin component of the b3Π and a3Δ states have been obtained.

The high-resolution infrared spectrum of iodine monobromide was recorded in absorption by Fourier transform spectroscopy. About 400 rovibrational transitions were observed near 260 cm−1. The lines were assigned to the v = 1 ← 0 and v = 2 ← 1 bands of the X1Σ+ electronic state of I79Br and I81Br. The infrared data were combined with millimeter-wave data from the literature to give improved molecular constants.Copyright 1993, 1999 Academic Press

The emission spectrum of FeF has been observed in the near infrared region from 9000 to 12000 cm−1. The bands were excited in a high temperature carbon tube furnace and recorded with a Fourier transform spectrometer at a resolution of 0.02 cm−1. The observed bands have been assigned as the 0–1, 0–0, 1–0, and 2–0 bands of theg4Δi–a4Δitransition analogous to theF4Δi–X4Δitransition of FeH at 1 μm. Each vibrational band consists of four sub-bands assigned as4Δ1/2–4Δ1/2,4Δ3/2–4Δ3/2,4Δ5/2–4Δ5/2, and4Δ7/2–4Δ7/2. The rotational analysis of these bands has been performed and molecular constants have been determined. This work represents the first observation of theg4Δ–a4Δ transition of FeF. We discuss the correspondence between the low-lying electronic states of FeF, FeH, and Fe+.

The high-resolution infrared emission spectra of bismuth monohydride and bismuth monodeuteride have been observed by Fourier transform spectroscopy. Gaseous BiH and BiD were produced by the direct reaction of the metal with hydrogen and deuterium, respectively. About 120 lines with v = 1 → 0 to v = 3 → 2 for each isotopomer have been measured. Dunham coefficients, Y_ij, have been derived in separate fits for the two molecules. In addition all data have been used in a combined fit to yield the mass-reduced Dunham constants, U_ij.Copyright 1993, 1999 Academic Press