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This work was conducted using the Picoscope signal extraction procedure, which revealed significant insights regarding the belian wood and its application in Gendang Melayu Sarawak (GMS) production. The amplitude of belian wood GMS signal remains constant, allowing it to sustain its timbre for a longer duration compared to durian wood GMS using the same procedure. Considering that the dimensions of the big belian (BB) and big durian (BD) GMS are almost the same, both GMS yield almost the same note, i.e. G1# (51.9 Hz). Considering that the dimensions of both the small belian (SB) and small durian (SD) GMS are almost the same, both GMS yield almost similar note, i.e. F3 (174 Hz) and E3 (164 Hz). Although both BB and BD showed consistent harmonics, BD only displays 2 harmonics. The SB and SD both display consistent harmonics. Both BB and BD showed pleasing tonal qualities. These occurred due to the closeness of the principal overtones to the consonant interval. [ABSTRACT FROM AUTHOR]

This work was conducted using the Picoscope signal extraction procedure, which revealed significant insights regarding the belian wood and its application in Gendang Melayu Sarawak (GMS) production. The amplitude of belian wood GMS signal remains constant, allowing it to sustain its timbre for a longer duration compared to durian wood GMS using the same procedure. Considering that the dimensions of the big belian (BB) and big durian (BD) GMS are almost the same, both GMS yield almost the same note, i.e. G1# (51.9 Hz). Considering that the dimensions of both the small belian (SB) and small durian (SD) GMS are almost the same, both GMS yield almost similar note, i.e. F3 (174 Hz) and E3 (164 Hz). Although both BB and BD showed consistent harmonics, BD only displays 2 harmonics. The SB and SD both display consistent harmonics. Both BB and BD showed pleasing tonal qualities. These occurred due to the closeness of the principal overtones to the consonant interval.

Nitrogen-14 (14N) overtone (OT) spectroscopy under fast magic angle spinning (MAS) conditions (>60 kHz) has emerged as a powerful technique for observing correlations and distances between 14N and ¹H, owing to the absence of the first-order quadrupolar broadenings. In addition, 14NOT allows selective manipulation of 14N nuclei for each site. Despite extensive theoretical and experimental studies, the spin dynamics of 14NOT remains under debate. In this study, we conducted experimental investigations to assess the spin dynamics of 14NOT using the rotational-echo saturation-pulse double-resonance (RESPDOR) sequence, which monitors population transfer induced by a14NOT pulse. The 14NOT spin dynamics is well represented by a model of a two-energy-level system. Unlike spin-1/2, the maximum excitation efficiency of 14NOT coherences of powdered solids, denoted by p, depends on the radiofrequency field (rf-field) strength due to orientation dependence of effective nutation fields even when pulse lengths are optimized. It is also found that the p factor, contributing to the 14NOT spin dynamics, is nearly independent of the B0 field. Consequently, the filtering efficiency of RESPDOR experiments exhibits negligible dependence on B0 when the 14NOT pulse length is optimized. The study also identifies the optimal experimental conditions for 14NOT/¹H RESPDOR correlation experiments. [ABSTRACT FROM AUTHOR]

DFB diode laser at 1434 nm was used to detect the hydroxyl radical OH in the first overtone region. Experiments were made at the most intense line Q(3/2) of 2Π3/2 electronic term. Collisional broadening for He buffer gas was measured. Using reliably defined integrated intensity of this line and calculated line contour, the absorption cross section could be obtained for different pressures. This enables measurement of the absolute concentration of OH in time-resolved experiments without calibration. The minimum concentration of radicals detected by absorption is 2 × 1012 cm–3 with the resolving time approximately 10–6 s. [ABSTRACT FROM AUTHOR]

Nitrogen-14 (14N) overtone (OT) spectroscopy under fast magic angle spinning (MAS) conditions (>60 kHz) has emerged as a powerful technique for observing correlations and distances between 14N and 1H, owing to the absence of the first-order quadrupolar broadenings. In addition, 14NOT allows selective manipulation of 14N nuclei for each site. Despite extensive theoretical and experimental studies, the spin dynamics of 14NOT remains under debate. In this study, we conducted experimental investigations to assess the spin dynamics of 14NOT using the rotational-echo saturation-pulse double-resonance (RESPDOR) sequence, which monitors population transfer induced by a14NOT pulse. The 14NOT spin dynamics is well represented by a model of a two-energy-level system. Unlike spin-1/2, the maximum excitation efficiency of 14NOT coherences of powdered solids, denoted by p, depends on the radiofrequency field (rf-field) strength due to orientation dependence of effective nutation fields even when pulse lengths are optimized. It is also found that the p factor, contributing to the 14NOT spin dynamics, is nearly independent of the B0 field. Consequently, the filtering efficiency of RESPDOR experiments exhibits negligible dependence on B0 when the 14NOT pulse length is optimized. The study also identifies the optimal experimental conditions for 14NOT/1H RESPDOR correlation experiments.

This study identified elements in a simple homemade gambus from a local crafter using a scientific approach. The gambus was made from geronggang wood (Cratoxylum arborescens), a light Malaysian hardwood with pink sapwood, distinct from the heartwood with brick-red or deep pink. The sound was processed to generate fast Fourier transform (FFT) and time-frequency analysis (TFA) using PicoScope and Adobe Audition software, respectively. The gambus A 1st string (note C4#) displayed a harmonic overtone at the 1st and 2nd octave. The 2nd string (note A3) showed harmonic overtone at the 1st, 2nd, and 3rd octave. The 3rd string (note D3#) showed a significant fundamental peak and harmonic overtone at the 1st, 2nd, 3rd, 4th, and 5th octave. The 4th string (note A2#) displayed consistent harmonic overtones at the 1st, 2nd, 3rd, 4th, and 5th octave. The 5th string (note E2) had a harmonic overtone at the 5th octave. Gambus A showed an inconsistent signal in the 6th string (note D2#) with inharmonic overtone at 3.35th and 6.79th overtones. The gambus A 1st to 6th strings are C4#, A3, D3#, A2#, E2, and D2#, respectively. The gambus B 1st to 6th strings are C4, G3, D3, A3, E3, and B2, respectively.

This study identified elements in a simple homemade gambus from a local crafter using a scientific approach. The gambus was made from geronggang wood (Cratoxylum arborescens), a light Malaysian hardwood with pink sapwood, distinct from the heartwood with brick-red or deep pink. The sound was processed to generate fast Fourier transform (FFT) and time-frequency analysis (TFA) using PicoScope and Adobe Audition software, respectively. The gambus A 1st string (note C4#) displayed a harmonic overtone at the 1st and 2nd octave. The 2nd string (note A3) showed harmonic overtone at the 1st, 2nd, and 3rd octave. The 3rd string (note D3#) showed a significant fundamental peak and harmonic overtone at the 1st, 2nd, 3rd, 4th, and 5th octave. The 4th string (note A2#) displayed consistent harmonic overtones at the 1st, 2nd, 3rd, 4th, and 5th octave. The 5th string (note E2) had a harmonic overtone at the 5th octave. Gambus A showed an inconsistent signal in the 6th string (note D2#) with inharmonic overtone at 3.35th and 6.79th overtones. The gambus A 1st to 6th strings are C4#, A3, D3#, A2#, E2, and D2#, respectively. The gambus B 1st to 6th strings are C4, G3, D3, A3, E3, and B2, respectively. [ABSTRACT FROM AUTHOR]

Spectra of HBr with a natural abundance of isotopologues were recorded in the region of the first overtone at room temperature at various sub-atmospheric pressures. The coefficients of self-broadening and shifting were found for two isotopologues of HBr. Both broadening and shifting coefficients for different isotopologues coincide within the error margins. The broadening coefficients are in good agreement with those reported previously, however they have a smaller error, about 1%. The shifting coefficients are reported for the first time. The obtained line intensities of both isotopologues are in reasonable agreement with values published earlier. [ABSTRACT FROM AUTHOR]

The research aimed at a comprehensive retrospective analysis of the development of "consonance and dissonance" as a musical and aesthetic category in physical and mathematical interpretation; defining the notion of consonance as a musical theoretical and aesthetic category, confirming the relevance of its use in physical and mathematical terminology to explain acoustic phenomena. Research methodology is based on the use of the retrospective method (or the retrospection method), which allowed identifying the theories of consonance and dissonance in the historical retrospective. The periodization method was used to find out individual stages in the development of science in order to discover the leading directions of scientific thought, identify new elements relating to various aspects of "consonance" and "dissonance". The study of the retrospective review of the development of the notions of consonance and dissonance in the physical and mathematical interpretation involved an interdisciplinary method a way of organizing research work, providing for the interaction of music and mathematics in the study of consonance and dissonance. Scientific novelty. This study is the first to reflect the general tendency towards the mathematization of the humanities and the humanitarization of the physical and mathematical areas of modern culture. Some provisions of musical acoustics were clarified in the context of creating a harmonious conceptual structure. The article presents the author's concept of clarifying the notion of phase in relation to the spectral structure of an audio signal based on the notion "slightly mistuned consonance". Conclusions. A retrospective review of the development of the notions of consonance and dissonance in the physical and mathematical interpretation was carried out and presented as a comprehensive description and review of the formation of concepts in the temporal sequence of their creation. Retrospectiveness through a review of significant discoveries and achievements in music and natural science allowed tracing the formation of the theories of consonance and dissonance from the standpoint of the interdisciplinarity of modern knowledge in the humanities. The further process of the development of sound musical art technologies requires a significantly higher scientific level of their study, the creation of a coherent conceptual system based on modern physical and mathematical sciences as well as computer science to explain sound acoustic phenomena. [ABSTRACT FROM AUTHOR]

This article presents an 8.6-GHz oscillator utilizing the third-order antisymmetric overtone (A3) in a lithium niobate (LiNbO3) radio frequency microelectromechanical systems (RF-MEMS) resonator. The oscillator consists of an acoustic resonator in a closed loop with cascaded RF tuned amplifiers (TAs) built on Taiwan Semiconductor Manufacturing Company (TSMC) RF general purpose (GP) 65-nm complementary metal-oxide semiconductor (CMOS). The TAs bandpass response, set by on-chip inductors, satisfies Barkhausen’s oscillation conditions for A3 while suppressing the fundamental and higher order resonances. Two circuit variations are implemented. The first is an 8.6-GHz standalone oscillator with a source-follower buffer for direct 50-Ω-based measurements. The second is an oscillator-divider chain using an on-chip three-stage divide-by-two frequency divider for a ~1.1-GHz output. The standalone oscillator achieves a measured phase noise of −56, −113, and −135 dBc/Hz at 1 kHz, 100 kHz, and 1 MHz offsets from an 8.6-GHz output while consuming 10.2 mW of dc power. The oscillator also attains a figure-of-merit of 201.6 dB at 100-kHz offset, surpassing the state-of-the-art (SoA) oscillators-based electromagnetic (EM) and RF-MEMS. The oscillator-divider chain produces a phase noise of −69.4 and −147 dBc/Hz at 1 kHz and 1 MHz offsets from a 1075-MHz output while consuming 12 mW of dc power. Its phase noise performance also surpasses the SoA L-band phase-locked loops (PLLs). With further optimization, this work can enable low-power multistandard wireless transceivers featuring high speed, high sensitivity, and high selectivity in small-form factors. [ABSTRACT FROM AUTHOR]

Raman scattering spectra in single crystals of lithium tantalate at 180-degree scattering geometry in a wide spectral frequency range (50 ÷ 2800 cm−1) were studied. Raman peaks were found in 1300 ÷ 2000 cm−1 region with frequencies exceeding doubled frequencies of LiTaO3 crystal lattice fundamental vibrations of A1 and E-type. The conditions for the manifestation of bound polar phonons in lithium tantalate Raman spectra were analyzed. The spectral intensity of Raman scattering in the overtone region of the spectrum of lithium tantalate was calculated taking into account the presence of a biphonon, and a satisfactory agreement between theory and experiment was obtained. [ABSTRACT FROM AUTHOR]

Raman scattering (RS) spectra in lithium tantalate single crystals are studied at 180-degree scattering geometry in a wide frequency spectral range (50–2500 cm–1). RS intensity peaks corresponding to fundamental transverse (TO) and longitudinal (LO) polar optical modes of this crystal are recorded. It is found that the high-frequency spectral range (1300–2000 cm–1) contains RS intensity peaks whose frequencies exceed doubled frequencies of A1- and E-type fundamental vibrations of the LiTaO3 lattice. The intensity of these peaks appeared comparable to the intensity of lines corresponding to A1- and E-type fundamental transverse and longitudinal polar optical modes. The conditions of the appearance of bound states of polar phonons in the RS spectra of lithium tantalate crystal are analyzed. [ABSTRACT FROM AUTHOR]

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This article presents a comprehensive guide to codesign lithium niobate (LiNbO3) lateral overtone bulk acoustic resonators (LOBARs) and voltage-controlled oscillators (VCOs) using discrete components on a printed circuit board (PCB). The analysis focuses on understanding the oscillator-level tradeoffs between the number of locked tones, frequency stability, tuning range, power consumption, and phase noise. Moreover, this article focuses on understanding the relationship between the abovementioned specifications and the different LOBAR parameters, such as electromechanical coupling (${k}_{t}^{{2}}$), quality factor (${Q}$), transducer design, and the resonator size. As a result of this study, the first voltage-controlled MEMS oscillator (VCMO) based on LiNbO3 LOBAR is demonstrated. Our LOBAR excites over 30 resonant modes in the range of 100–800 MHz with a frequency spacing of 20 MHz. The VCMO consists of an LOBAR in a closed loop with two amplification stages and a varactor-embedded tunable LC tank. By adjusting the bias voltage applied to the varactor, the tank can be tuned to change the closed-loop gain and phase responses of the oscillator so that the Barkhausen conditions are satisfied for a particular resonant mode. The tank is designed to allow the proposed VCMO to lock to any of the ten overtones ranging from 300 to 500 MHz. These ten tones are characterized by average ${Q}\text{s}$ of 2100, ${k}_{t}^{{2}}$ of 1.5%, figure of merit ($\text {FOM} = {Q} {k}_{t}^{{2}}$) of 31.5 enabling low phase noise, and low-power oscillators crucial for Internet of Things (IoT). Due to the high ${Q}\text{s}$ of the LiNbO3 LOBAR, the measured VCMO shows a close-in phase noise of −100 dBc/Hz at 1-kHz offset from a 300-MHz carrier and a noise floor of −153 dBc/Hz while consuming 9 mW. With further optimization, this VCMO can lead to direct radio frequency (RF) synthesis for ultralow-power transceivers in multimode IoT nodes. [ABSTRACT FROM AUTHOR]

This letter presents a 12.9-GHz silicon germanium (SiGe) Pierce oscillator using a third antisymmetric overtone in a lithium niobate (LiNbO3) resonator for 5G communications. Quarter-wave resonators are used to satisfy the Barkhausen oscillation conditions for the third overtone while suppressing the fundamental and higher order resonances. The oscillator achieves a measured phase noise of −70 and −111 dBc/Hz at 1 and 100-kHz offsets from a 12.9-GHz carrier while consuming 20 mW of dc power. The oscillator achieves a figure-of-merit of 200 dBc/Hz at 100-kHz offset, surpassing the state-of-the-art electromagnetic (EM) and overtone MEMS oscillators. The achieved oscillation frequency is the highest reported to date for an MEMS oscillator. The demonstrated performance shows the strong potential of microwave acoustic oscillators for 5G frequency synthesis. This work will enable low-power 5G transceivers featuring high speed, high sensitivity, and high selectivity in small form factors. [ABSTRACT FROM AUTHOR]

This work presents a new acoustic MEMS resonator technology, dubbed Aluminum Nitride (AlN) Combined Overtone Resonator (COR), capable of addressing the filter requirements for the 5G high frequency bands in the 6-40GHz range. The COR exploits the multimodal excitation of two higher-order Lamb waves (2nd and 3rd order Asymmetrical Lamb Waves) in a suspended thin-film AlN plate to transduce a 2-dimensional vibration mode with high electromechanical coupling coefficient kt2 (up to 1.9%) and quality factor Q > 1100 at twice the frequency of a fundamental thickness-extensional mode in the same structure. Analytical and finite-element method (FEM) models are developed to describe the working principle of the COR technology and predict the achievable kt2, Q and lithographic frequency tunability. An 8.8 GHz COR prototype was fabricated showing a high kt2 ~0.3 % (using a simple top-electrode-only configuration with a 2-mask process) and a groundbreaking Q ~ 1100 which is the highest ever achieved among piezoelectric resonators above 6 GHz. The f - Q product ~1 × 1013 is the highest among all demonstrated piezoelectric resonators with metallic coverage >50%. Additionally, the capability of the COR technology to deliver contiguous filters with bandwidths between 355 and 592 MHz (aggregated BW >2GHz) in the mmWave spectrum, with relaxed lithographic requirements, is demonstrated by FEM. [2019-0229] [ABSTRACT FROM AUTHOR]

Gamelan in general is categorized as a group of gongs. This traditional Malay gamelan ensemble is in a slendro scale i.e. five notes per octave. The rhythms, pitch, duration and loudness classify the various groups of gongs such as bonang, kenong, gender, peking and gambang. The cast bronze peking, kenong and bonang were chosen from a range of Malay gamelan ensemble from Universiti Malaysia Sarawak (UNIMAS), Universiti Putra Malaysia (UPM), Universiti Kebangsaan Malaysia (UKM) and Universiti Teknologi Mara (UiTM). The sounds were recorded by PicoScope Oscilloscope. The PicoScope software displays waveform and spectrum in time and frequency domain respectively. The peking lowest and highest frequencies from UiTM were 293 Hz and 1867 Hz, from UPM were 644 Hz and 1369 Hz, from UKM were 1064 Hz and 2131 Hz and from UNIMAS were 1072 Hz and 2105 Hz respectively. The kenong lowest and highest frequencies from UiTM were 259 Hz and 463 Hz, from UPM were 294 Hz and 543 Hz, from UKM were 300 Hz and 540 Hz and from UNIMAS were 293 Hz and 519 Hz respectively. The fundamental frequencies of bonang from UPM were higher than that of UKM, UiTM and UNIMAS. The harmonics were not successive but interrupted by another frequency. The harmonics of each bonang was similar except for gamelan from UKM. [ABSTRACT FROM AUTHOR]

Anharmonic quantum chemical calculations were employed to simulate and interpret a near-infrared (NIR) spectrum of caffeine. First and second overtones, as well as binary and ternary combination bands, were obtained, accurately reproducing the lineshape of the experimental spectrum in the region of 10,000–4000 cm−1 (1000–2500 nm). The calculations enabled performing a detailed analysis of NIR spectra of caffeine, including weak bands due to the second overtones and ternary combinations. A highly convoluted nature of NIR spectrum of caffeine was unveiled, with numerous overlapping bands found beneath the observed spectral lineshape. To properly reflect that intrinsic complexity, the band assignments were provided in the form of heat maps presenting the contributions to the NIR spectrum from various kinds of vibrational transitions. These contributions were also quantitatively assessed in terms of the integral intensities. It was found that the combination bands provide the decisively dominant contributions to the NIR spectrum of caffeine. The first overtones gain significant importance between 6500–5500 cm−1, while the second overtones are meaningful in the higher wavenumber regions, particularly in the 10,000–7000 cm−1 region. The obtained detailed band assignments enabled deep interpretation of the absorption regions of caffeine identified in the literature as meaningful for analytical applications of NIR spectroscopy focused on quantitative analysis of caffeine content in drugs and natural products.

Overtone bands in the spectral range of 1300−1920 cm–1 have been found in Raman scattering spectrum of lithium tantalate single crystals. The Raman spectra were recorded in the 180° scattering geometry. The intensity of overtone transitions differs for different samples and, in some cases, is comparable with the Raman scattering intensity at the fundamental modes of a lithium tantalate single crystal. [ABSTRACT FROM AUTHOR]

We report experimental results on the broadening and shifting coefficients in a large interval of J quantum numbers in the fundamental and first overtone vibration-rotation bands of the HCl molecule in mixtures with helium. Many of the values, especially for the overtone transition, are novel. The uncertainties for the isotope-averaged broadening coefficients amount to 2% on average for the fundamental and 1.5% for the overtone bands. Shifts have a typical uncertainty of 3%. [ABSTRACT FROM AUTHOR]

The NIR spectra from 1000 to 2500 nm of 18 different explosives, propellant powders and energetic salts were collected and interpreted. NIR spectroscopy is known to provide information about the combination bands and overtones of highly anharmonic vibrations as those occurring in X H bonds (C H, N H and O H). Particularly intense and complex were the bands corresponding to the first combination region (2500–1900 nm) and first overtone stretching mode (2ν) of C H and N H bonds (1750–1450 nm). Inorganic oxidizing salts including sodium/potassium nitrate, sodium/potassium chlorate, and sodium/potassium perchlorate displayed low intense or no NIR bands. [ABSTRACT FROM AUTHOR]

The frequencies and absorption intensities of the five kinds of conformers of 1,3-butanediol with the same carbon skeleton (GG′) were calculated by anharmonic calculation for the fundamentals and first overtones of OH stretching vibrations. The four kinds of conformers form intramolecular hydrogen bonds and one conformer did not. Intramolecular hydrogen bond formation shifted the frequency of fundamental and first overtone of H-bonding OH stretching vibration to the lower frequency. The absorption intensities of the fundamentals as well as the vibrational anharmonicities increased upon hydrogen bond formation, while the intensities of first overtones decreased. The differences of conformers were clearly seen in the frequencies of the first overtones of free OH. [ABSTRACT FROM AUTHOR]

A new gas-phase infrared (IR) spectrum of acryloyl fluoride (ACRF, CH 2 CH CF O) with a resolution of 0.1 cm − 1 in the range 4000–450 cm − 1 was measured. Theoretical ab initio molecular structures, full quartic potential energy surfaces (PES), and cubic surfaces of dipole moments and polarizability tensor components (electro-optical properties, EOP) of the s-trans and s-cis conformers of the ACRF were calculated by the second-order Møller-Plesset electronic perturbation theory with a correlation consistent Dunning triple- ζ basis set. The numerical-analytic implementation of the second-order operator canonical Van Vleck perturbation theory was employed for predicting anharmonic IR and Raman scattering (RS) spectra of ACRF. To improve the anharmonic predictions, harmonic frequencies were replaced by their counterparts evaluated with the higher-level CCSD(T)/cc-pVTZ model, to form a “hybrid” PES. The original operator representation of the Hamiltonian is analytically reduced to a quasi-diagonal form, integrated in the harmonic oscillator basis and diagonalized to account for strong resonance couplings. Double canonical transformations of EOP expansions enabled prediction of integral intensities of both fundamental and multi-quanta transitions in IR/RS spectra. Enhanced band shape analysis reinforced the assignments. A thorough interpretation of the new IR experimental spectra and existing matrix-isolation literature data for the mixture of two conformers of ACRF was accomplished, and a number of assignments clarified. [ABSTRACT FROM AUTHOR]

We present experimental data on the line pressure broadening and shift coefficients in the first vibrational overtone band of HCl in mixtures with CO and CO 2 gas at room temperature. CO-broadening coefficients are published for the first time. The CO 2 -broadening coefficients and shifts for both systems are in very good agreement with the literature data and have better accuracy than earlier results. Collisions with CO 2 lead to stronger broadening for the most lines than collisions with CO. Similar to the broadening coefficients, the absolute values of CO 2 -induced shift coefficients are larger than those for HCl-CO system. However, the asymmetric shifts are very similar for both systems except for R 2 (0) and P 2 (1) lines, where the interaction anisotropy has the strongest influence. [ABSTRACT FROM AUTHOR]