Cartan rediscovered in general relativity

General Relativity and Gravitation - Supplementing earlier literature by e.g. Tipler et al. (1980), Israel (1987), Thorne (1994), Earman (1999), Senovilla and Garfinkle (2015), Curiel (2019) and...     

Novel peak assignments of in vivo (13)C MRS in human brain at 1.5 T

(13)C MRS studies at natural abundance and after intravenous 1-(13)C glucose infusion were performed on a 1.5-T clinical scanner in four subjects. Localization to the occipital cortex was achieved by a surface coil. In natural abundance spectra glucose C(3beta,5beta), myo-inositol, glutamate C(1,2,5), glutamine C(1,2,5), N-acetyl-aspartate C(1-4,C=O), creatine CH(2), CH(3), and C(C=N), taurine C(2,3), bicarbonate HCO(-)(3) were identified. After glucose infusion (13)C enrichment of glucose C(1alpha,1beta), glutamate C(1-4), glutamine C(1-4), aspartate C(2,3), N-acetyl-aspartate C(2,3), lactate C(3), alanine C(3), and HCO(-)(3) were observed. The observation of (13)C enrichment of resonances resonating at >150 ppm is an extension of previously published studies and will provide a more precise determination of metabolic rates and substrate decarboxylation in human brain.     

SPME-GC-MS分析瀑布毛峰茶叶的赋香成分

采用顶空-固相微萃取法(SPME)从瀑布毛峰茶叶中提取挥发性成分,用气相色谱-质谱法(GC-MS)分析其组成。从一级和特级茶叶中分别鉴定了相对含量大于0.50%的化合物48个和41个,其中共同组分27个。一级瀑布毛峰茶叶的主要挥发性成分有壬醛(9.22%),芳樟醇(4.75%),牛儿醇(4.07%),(Z)-3-己烯-1-醇(3.53%),十一醛(3.16%),邻苯二甲酸二异丁酯(2.94%),十六烷(2.35%),己醛(2.00%),1-辛醇(1.97%),6-甲基-5-庚烯-2-酮(1.86%)。特级瀑布毛峰茶叶的主要挥发性成分有:壬醛(8.85%),1-辛烯-3-醇(6.37%),十一醛(4.81%),2,5,5-三甲基-1-己烯(2.84%),辛醛(2.73%),1-辛醇(2.63%),6-甲基-5-庚烯-2-酮(2.60%),芳樟醇(2.20%),1-戊醇(2.20%),己醛(2.16%)。两个等级的瀑布毛峰茶的主要挥发性成分大致相同,但各成分的含量存在一定差异。     

Specific features in supersonic nonlinear dynamics of domain walls in rare-earth orthoferrites

Physics of the Solid State - The dynamics and temperature dependences of the mobility of domain walls in EuFeO3 (from 4.2 to 300 K), TmFeO3 (from 100 to 300 K), LuFeO3 (300 K), YFeO3 (460 K), and...     

Millimeter-Wave Spectroscopy of HCCCP in Excited Vibrational States

The rotational spectra of the unstable HCCCP molecule have been investigated in the millimeter-wave region for the main excited vibrational states which lie below 1000 cm(-1), namely nu(4) (C&bond;C stretch), nu(5) (HCC bend), nu(6) (CCC bend), nu(7) (CCP bend), 2nu(6), 2nu(7), 3nu(7), 4nu(7), nu(5) + nu(7), and nu(6) + nu(7). l-type resonance effects have been taken into account in the analysis of the spectra, so that the values of the anharmonicity constants x(L(66)), x(L(77)), x(L(57)), and x(L(67)) could be determined. The anharmonic interactions which couple the nu(4) state with nu(6) + nu(7), 2nu(6), and 4nu(7) have been also considered, yielding the unperturbed value of the alpha(4) vibration-rotation coupling constant. Copyright 2001 Academic Press.     

High-Order Resonances in the Water Molecule

The water-vapor spectra in the near-infrared and visible region were reanalyzed with the purpose of finding experimental evidences of unusual high-order resonance between "dark" high-bending and "bright" stretch vibration states. About 70 transitions to the (050), (060), (070), (080), (160), (061), (170), (071), and, even (0 10 0) bending states, and their resonating partners were assigned in the spectra that gives the experimental energy levels lying near or above the potential energy barrier to linearity. The assignments were confirmed by combination differences and simultaneous observation of both perturbed and perturbing levels. It was found that the high-order resonances with large changing of vibration quantum numbers are typical for the water molecule and they are caused by the strong centrifugal distortion near the linear configuration. These resonances destroy the usual polyad scheme originating from well-known Coriolis, Darling-Dennison, and Fermi resonances in H(2)O molecule. Copyright 2001 Academic Press.     

Use of Cerium (IV) in the Spectrophotometric and Spectrofluorimetric Determinations of Penicillins and Cephalosporins in Their Pharmaceutical Preparations

Spectrophotometric and spectrofluorimetric procedures for the quantitative determination of four penicillins [Amoxycillin (AMX), Bacampicillin (BAC), Piperacillin (PPN) and Sultamcillin (SULT)] and ten cephalosporins [Cefadroxil (CDL), Cefamandole nafate (MAN), Cefuroxime axetil or sodium (CFX), Cefaclor (CFCR), Ceftazidime (CZD), Ceftizoxime (CTIZ), Ceftriaxone (CTRX), Cefoperazone (CPZ), Cefixime (CXIM) and Cefpodoxime proxetil (CFPD)] are described. Both methods are based on the acidic oxidation of the antibiotics with cerium (IV) at elevated temperature. The effect of the reagent concentration, volume of the acid,and the heating temperature were studied to optimize the reaction conditions. Each antibiotic was determined by either measuring the absorbance difference at 317 nm or the cerous inherent fluorescence at 256 and 356 nm for excitation and emission wavelengths, respectively. The two procedures have been successfully applied to the assay of these antibiotics in their pharmaceutical dosage forms. The obtained results have been statistically compared with those obtained by the official methods.     

Sonolysis of metal beta-diketonates in alkanes

The kinetics of metal beta-diketonates sonolysis was studied in hexadecane solutions using a UV/VIS spectrophotometric technique. The following complexes were prepared and studied: Cu(HFAA)(2), Cu(DPM)(2), Fe(ACAC)(3), Ni(DPM)(2), Er(DPM)(3), Nd(DPM)(3), Th(DPM)(4), UO(2)(BTFA)(2).TOPO, and Np(HFAA)(4), where HHFAA is hexafluoroacetylacetone, HDPM is dipivaloylmethane, HACAC is acetylacetone, HBTFA is benzoyltrifluoroacetone, and TOPO is trioctylphosphine oxide. Sonolysis was performed under the following conditions: ultrasonic frequency 22 kHz, intensity of ultrasound 3-5 Wcm(-2), temperature 70-92 degrees C, Ar atmosphere. The kinetic behavior of the studied complexes are interpreted using a two-site model of the sonochemical processes. In the case of metal beta-diketonates with high vapor pressure the sonochemical reactions tend to occur in the gaseous phase of the cavitating bubbles. The sonolysis of less volatile complexes first occur in the liquid reaction zone surrounding the bubbles. Sonication of the studied complexes results in the formation of X-ray amorphous products consisted of a mixture of metal beta-diketonates partial degradation products. Heating of as-prepared sonication products in air yields nanocrystalline oxides of corresponding metals.     

Gamma radiation in the decay of249Cf

Gamma radiation following alpha decay of²⁴⁹Cf was investigated with high resolution Ge(Li) detectors in singles and coincidence arrangements. Nine new γ-rays were identified and placed in the previously-known decay scheme. Their energies in keV and intensities relative to the 388 keV (100) γ-ray are: 37.5±0.1 (0.026), 65.87±0.1 (0.017), 121.5±0.4 (0.070), 229.2±0.2 (0.072), 255.7±0.2 (0.065), 390.5±0.2 (0.025), 405.9±0.1 (0.014), 588.8±0.1 (0.003), and 643.5±0.1 (0.007). Coincidence measurements revealed that the intensity of the 54.7 keV γ-ray is shared by three intraband transitions and that the 121.5 keV crossover transition is present in the ground-state band.     

Mean lifetimes of levels in 55Co

The mean lifetimes of levels in ⁵⁵Co below 5.2 MeV have been investigated with the Doppler-shift attenuation method and the ⁵⁴Fe(³He, d)⁵⁵Co reaction at 12 MeV. Scattered particles were detected in two E-ΔE telescopes at ±55° with respect to the beam axis, in coincidence with γ-rays observed at 90° and 130° in a 50 cm³ Ge(Li) detector. Mean lifetimes are reported for the following levels (energy in keV, lifetime in fs): 2166 (139±18), 2566 (680±200), 2923 (>245), 2939 (190±65), 3303 (99±22), 3323 (54±15), 3642 (680_?300⁺⁴⁰⁰), 3943 (>170), 4164 (54±15), 4180 (<16), 4722 (<33), 4749 (<70) and 5174 (<40). The experimental results are compared with a detailed shell-model calculation.     

Rotational spectra of DCCCN in some excited vibrational states

We have observed and analyzed the millimeter-wave spectrum of deuterated cyanoacetylene (DCCCN) in 12 excited vibrational states. The Hamiltonian of K. M. T. Yamada, F. W. Birss, and M. R. Aliev (J. Mol. Spectrosc. 112, 347–356 (1985)) has allowed the determination of accurate rotational and l-type doubling constants for the following isolated states: (v₄, v₅, v₆, v₇) = (1001), (0001), (0002), (0003), (0010), (0100), (0101), (0011), and 0012). The anharmonic resonance between the (1000), (0020), and (0004) states has been observed and analyzed, yielding the unperturbed rotational constants and the Fermi interaction constant.     

Visualization activities in Indonesia

Though it is still in its initial state, visualization techniques as one of the supportive components in the industrial transformation as well as a research tool have, however, gained some supports in universities and research institutes. This paper presents a review of activities related to the visualization research and application in universities and research institutes in Indonesia, namely at the Center for Applied Physics — Indonesia Institute for Sciences (P3FT-LIPI), University of Indonesia (UI), Institute of Technology Surabaya (ITS), Institute of Technology Bandung (ITB), and Aero-Gas Dynamics and Vibration Laboratory (LAGG-BPP-Teknologi).     

Photoglottographic measures in parkinson's disease

This study examines the usefulness of photoglottographic measures in reflecting the phonatory effect of Parkinson's disease. In the first experiment, data obtained by photoglottography were compared between 15 male patients with Parkinson's disease and 15 normal male speakers of similar age. Six photoglottographic parameters, mean open quotient (OQ), mean speed quotient (SQ), perturbation of open quotient (POQ), perturbation of speed quotient (PSQ), frequency perturbation ratio (FPR), and amplitude perturbation ratio (APR), in sustained vowel phonation were investigated. Increased SQ (t = -2.731, df = 28, P = 0.011) and POQ (t = -2.584, df = 28, P = 0.015) were significantly associated with data from patients in comparison to normal speakers. The FPR, APR, and OQ were not significantly different between normal subjects and patients. A follow-up experiment, including 12 female and 19 male patients with Parkinson's disease, was designed to evaluate the sensitivity of SQ and POQ in detecting vocal dysfunction. The sensitivity of SQ was found to be relatively high (93.5%), while that of POQ was low (45.2%). Methodological issues regarding the effects of gender, age, stage of the disease, and treatment on photoglottographic measures in Parkinson's disease were discussed.     

硒杂环-金属离子在乙醇溶液中的紫外吸收光谱

研究了不同分子结构的硒杂环化合物—金属离子在乙醇溶液中的紫外吸收光谱 ,硒杂环均为苤硒脑类化合物 (piazselenoles,简称Pis) :4 ,5 benzopiazselenole(BP) ;anthra[1,2 c][1,2 ,5 ]selenadiazol 6 ,11 dione(AS) ;piazselenole(PS) ;5 methyl piazselenole(MP) ;4 ,6 diBr piazselenole(DBP) ;4 ,4 ' dipiazselenole(DP)。结果表明 :Pis随分子共轭体系增大或共轭效应增强 ,紫外吸收波长λ呈现有规律地红移 ,摩尔吸光系数ε增大 ;Sn(Ⅳ ) ,Cd(Ⅱ ) ,Cr(Ⅲ ) ,Sb(Ⅲ ) ,Fe(Ⅲ ) ,Fe(Ⅱ )及Cu(Ⅱ ) BP≥ 1均使BP的紫外吸收增强 ,Zn(Ⅱ )的影响较小。Sn(Ⅳ ) ,Cr(Ⅲ )和Sb(Ⅲ )均可使Pis的短波位置的紫外吸收增强 ,使MP于 2 33nm处的峰形变钝。     

凤党脂溶性成分的GC-MS分析

采用索氏提取法提取凤党脂溶性成分,甲酯化后,气相色谱-质谱联用（GC-MS）进行分析,计算机检索结合人工解析进行成分分析和鉴定,共分离得到48个峰,鉴定了其中39种成分。在凤党脂溶性成分中主要含有亚油酸（29.73%）、棕榈酸（12.94%）、油酸（3.14%）、亚麻酸（1.83%）、硬脂酸（1.64%）和角鲨烯（12.00%）等。     

The Physical Tourist Physics in Glasgow: A Heritage Tour

I trace the history of the physical and applied sciences, and particularly physics, in Glasgow. Among the notable individuals I discuss are Joseph Black (1728–1799), James Watt (1736–1819), William John Macquorn Rankine (1820–1872), William Thomson, Lord Kelvin (1824–1907), John Kerr (1824–1907), Frederick Soddy (1877–1956), John Logie Baird (1888–1946), and Ian Donald (1910–1987), as well as physics-related businesses.The locations, centering on the city center and University of Glasgow, include sites both recognizable today and transformed from past usage, as well as museums and archives related to the history and interpretation of physics.     

东北苍耳子挥发油化学成分分析

利用乙醚抽提东北苍耳子挥发油,GC-MS结合计算机检索对其化学成分进行分析鉴定,用色谱峰面积归一化法计算各组分的相对含量.分离出89个组分,鉴定了其中74个组分,占总挥发油量的85.63%.东北苍耳子挥发油的主要成分为3-甲基丁酸(16.421%)、3-甲基-戊酸(15.882%)、苯乙醛(11.281%)、已酸(5.051%)、糠醛(4.716%)、苯甲醇(2.358%)、苯乙醇(2.282%)等.     

Low-energy coexisting band in 154Gd

A low-energy coexisting band Jpi (Ex keV) 0(+) (1182), 2(+) (1418), 4(+) (1701) is identified in the deformed nucleus, 154Gd. Detailed gamma-ray spectroscopy following the beta decays of 154Eu (J=3), (g,m(1),m(2))154Tb (J=0,3,7) is used to establish this structure. The structure is explained in terms of the pairing and deformation degrees of freedom, a "pairing isomer," which results from the nu[505] upward arrow Nilsson intruder orbital.